<PAGE>
As filed with the Securities and Exchange Commission on August 12, 2002

                                                           File No. 333-________

                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549
                            -------------------------
                                    FORM S-8
                             REGISTRATION STATEMENT
                                      Under
                           THE SECURITIES ACT OF 1933
                            -------------------------

                           AUTHENTIDATE HOLDING CORP.
             (Exact name of Registrant as specified in its charter)

         Delaware                2165 Technology Drive        14-1673067
(State of Incorporation)         Schenectady, NY 12308      (I.R.S. Employer
                                    (518) 346-7799        Identification Number)

               (Address, including zip code, and telephone number,
        including area code, of registrant's principal executive offices)

                  2001 NON-EXECUTIVE DIRECTOR STOCK OPTION PLAN
                               (Full Name of Plan)
                                -----------------
                                  John T. Botti
                             Chief Executive Officer
                              2165 Technology Drive
                              Schenectady, NY 12308
                                 (518) 346-7799
          (Name and address, including zip code, and telephone number,
                   including area code, of agent for service)
                                -----------------
                                 With copies to:
                             Victor J. DiGioia, Esq.
                           Michael A. Goldstein, Esq.
                            GOLDSTEIN & DIGIOIA, LLP
                              369 Lexington Avenue
                            New York, New York 10017
                            Telephone (212) 599-3322
                            Facsimile (212) 557-0295
<PAGE>
                         CALCULATION OF REGISTRATION FEE

<TABLE>
<CAPTION>
===================================================================================================================================
                                                                                 Proposed            Proposed
                                                                                  Maximum             Maximum
                                                                                 Offering             Aggregate        Amount of
Title of Each Class of Securities Being              Amount to be                Price per            Offering         Registration
Registered                                           Registered                  Share(1)             Price(1)         Fee
- -----------------------------------------------------------------------------------------------------------------------------------
<S>                                                  <C>                         <C>                 <C>               <C>
Common Stock, $.001 par
value......................                            500,000                   $3.55               $1,775,000          $163.30
- -----------------------------------------------------------------------------------------------------------------------------------
Total......................                            500,000                                       $1,775,000          $163.30

===================================================================================================================================
</TABLE>

(1)      Estimated solely for the purpose of determining the registration fee,
         in accordance with Rule 457(h), based on the average of the high and
         low prices of a share of Common Stock as quoted on the Nasdaq National
         Market on August 8, 2002 ($3.55 per share).

         ---------------------------

         THE REGISTRANT HEREBY AMENDS THIS REGISTRATION STATEMENT ON SUCH DATE
OR DATES AS MAY BE NECESSARY TO DELAY ITS EFFECTIVE DATE UNTIL THE REGISTRANT
SHALL FILE A FURTHER AMENDMENT WHICH SPECIFICALLY STATES THAT THIS REGISTRATION
STATEMENT SHALL THEREAFTER BECOME EFFECTIVE IN ACCORDANCE WITH SECTION 8(a) OF
THE SECURITIES ACT OF 1933 OR UNTIL THE REGISTRATION STATEMENT SHALL BECOME
EFFECTIVE ON SUCH DATE AS THE COMMISSION ACTING PURSUANT TO SECTION 8(a) MAY
DETERMINE.


                                       ii
<PAGE>
                                     PART I

              INFORMATION REQUIRED IN THE SECTION 10(a) PROSPECTUS


ITEM 1.  PLAN INFORMATION

         This Registration Statement relates to 500,000 shares of Common Stock,
$.001 par value, of Authentidate Holding Corp., authorized for issuance in
connection with the grant of options to the company's non-executive directors
and other authorized persons under its 2001 Non-Executive Director Stock Option
Plan. At the Annual Meeting of Stockholders held on January 24, 2002, our
shareholders approved the adoption of the 2001 Non- Executive Director Stock
Option Plan. Under the 2001 Non-Executive Director Plan, each non-executive
director will automatically be granted an option to purchase 20,000 shares upon
joining the Board and an option to purchase 10,000 shares each September 1st
thereafter, pro rata, based on the time the director has served in such capacity
during the previous year. The exercise price for options granted under the 2001
Non-Executive Director Plan shall be 100% of the fair market value of the common
stock on the date of grant.

         Pursuant to Rule 428(b)(1) of the Securities Act of 1933, as amended,
the documents containing the information specified in Part I for Form S-8 will
be sent or given to participants in the Non-Executive Director Plan. In
accordance with the instructions to Part I of Form S-8, the Non-Executive
Director Plan and related documents are not being filed with the Securities and
Exchange Commission as part of the registration statement or as prospectuses or
prospectus supplements pursuant to Rule 424. The foregoing documents and the
documents incorporated by reference in this Registration Statement, taken
together, constitute a Prospectus that meets the requirements of Section 10(a)
of the Securities Act of 1933, as amended.

         There is also as part of Part I of this registration statement, a
re-offer prospectus, prepared in accordance with the requirements of Part I of
Form S-3, relating to and to be used in connection with any re-offer and resale
of an aggregate of 500,000 shares of our common stock by:

         -        persons who may be deemed to be our affiliates;

         -        any shares of common stock issued or to be issued to such
                  persons;

         -        and all persons holding restricted securities issued

pursuant to the exercise of the options granted under the 2001 Non-Executive
Director Stock Option Plan, all as permitted by General Instruction C of Form
S-8.

ITEM 2. REGISTRANT INFORMATION AND NON-EXECUTIVE DIRECTOR STOCK OPTION PLAN
ANNUAL INFORMATION

         Authentidate Holding Corp. will provide without charge to each person
to whom a copy of this Prospectus is delivered, upon the written or oral request
of any such person: (1) a copy of any document described in Item 3 of Part II of
this Registration Statement, which documents are incorporated by reference in
the Section 10(a) Prospectus (other than exhibits); and (2) the documents
required to be delivered to non-executive directors pursuant to Rule 428(b).
Requests for such copies should be directed to Dennis Bunt, Chief Financial
Officer, Authentidate Holding Corp., 2165 Technology Drive, Schenectady, New
York 12308, telephone (518) 346-7799.
<PAGE>
RE-OFFER
P R O S P E C T U S              500,000 Shares


                           AUTHENTIDATE HOLDING CORP.

                                  Common Stock

         We are registering for resale an aggregate of 500,000 shares of common
stock, $.001 par value of Authentidate Holding Corp., which shares we will issue
upon the exercise of up to 500,000 shares of our common stock reserved for
issuance upon the exercise of options granted under our 2001 Non-Executive
Director Stock Option Plan.

         We will not receive any of the proceeds from the sale of the Shares by
the Selling Security Holders.

         Our common stock is traded in the over-the counter market and is quoted
on the Nasdaq National Market under the symbol "ADAT". On August 7, 2002, the
closing price for the common stock as reported on Nasdaq was $3.55.

          The shares may be sold from time to time by the selling security
holders, or by their transferees. No underwriting arrangements have been entered
into by the selling security holders. The distribution of the shares by the
selling security holders may be effected in one or more transactions that may
take place on the over the counter market, including ordinary brokers
transactions, privately negotiated transactions or through sales to one or more
dealers for resale of the shares as principals, at market prices prevailing at
the time of sale, at prices related to such prevailing market prices or at
negotiated prices. Usual and customary or specifically negotiated brokerage fees
or commissions may be paid by the selling security holders in connection with
such sales. The selling security holders and intermediaries through whom such
shares are sold may be deemed underwriters within the meaning of the Act, with
respect to the shares offered by them.

          PLEASE SEE "RISK FACTORS" BEGINNING ON PAGE 12 TO READ ABOUT
           CERTAIN FACTORS YOU SHOULD CONSIDER BEFORE BUYING SHARES OF
                                  COMMON STOCK.


          NEITHER THE SECURITIES AND EXCHANGE COMMISSION NOR ANY OTHER
          REGULATORY BODY HAS APPROVED OR DISAPPROVED THESE SECURITIES
         OR PASSED UPON THE ACCURACY OR ADEQUACY OF THIS PROSPECTUS. ANY
              REPRESENTATION TO THE CONTRARY IS A CRIMINAL OFFENSE.



                    Re-Offer Prospectus dated August 12, 2002


                                       iv
<PAGE>
                               TABLE OF CONTENTS

<TABLE>
<CAPTION>
                                                                         PAGE
                                                                         ----
<S>                                                                      <C>
AVAILABLE INFORMATION..............................................        1

INCORPORATION OF CERTAIN DOCUMENTS BY REFERENCE....................        1

PROSPECTUS SUMMARY.................................................        3

THE COMPANY........................................................        3

THE OFFERING.......................................................       11

RISK FACTORS.......................................................       12

USE OF PROCEEDS ...................................................       20

SELLING SECURITY HOLDERS...........................................       21

PLAN OF DISTRIBUTION...............................................       22

REPORTS TO SHAREHOLDERS............................................       24

LEGAL MATTERS......................................................       24

EXPERTS  ..........................................................       24

ADDITIONAL INFORMATION.............................................       24

FORWARD LOOKING STATEMENTS.........................................       25
</TABLE>


                                        v
<PAGE>
                              AVAILABLE INFORMATION

         We are subject to the informational reporting requirements of the
Securities Exchange Act of 1934, as amended, and, in accordance therewith, file
reports and other information with the Securities and Exchange Commission.
Reports, proxy and information statements and other information that we file
with the Commission pursuant to the informational requirements of the Exchange
Act may be inspected and copied at the public reference facilities maintained by
the Commission at 450 Fifth Street, N.W., Washington, D.C. 20549 and at the
following Regional Offices of the Commission: Northeast Regional Office,
Securities and Exchange Commission, 233 Broadway, New York, New York 10279; and
Chicago Regional Office, 500 West Madison Street, Room 1400, Chicago, Illinois
60661. Copies of such material may be obtained from the public reference section
of the Commission at 450 Fifth Street, N.W., Washington, D.C. 20549, at
prescribed rates. You may obtain information on the operation of the Public
Reference Room by calling the SEC at 1-800-SEC-0330. The SEC maintains an
Internet site, http://www.sec.gov, that contains reports, proxy and information
statements and other information that we file electronically with the SEC.

         We have filed with the Commission a registration statement on Form S-8
under the Securities Act with respect to the shares of common stock offered by
this re-offer prospectus. This re-offer prospectus does not contain all the
information set forth in or annexed as exhibits to the registration statement.
For further information with respect to our company and the shares of common
stock offered by this re-offer prospectus, reference is made to the registration
statement and to the financial statements, schedules and exhibits filed as part
thereof or incorporated by reference herein. Copies of the registration
statement, together with such financial statements, schedules and exhibits, may
be obtained from the public reference facilities of the Commission at the
addresses listed above, upon payment of the charges prescribed therefor by the
Commission. Statements contained in this re-offer prospectus as to the contents
of any contract or other document referred to are not necessarily complete and,
in each instance, reference is made to the copy of such contract or other
documents, each such statement being qualified in its entirety by such
reference. Copies of such contracts or other documents, tot he extent that they
are exhibits to this registration statement, may be obtained from the public
reference facilities of the Commission, upon the payment of the charges
prescribed therefor by the Commission.

                 INCORPORATION OF CERTAIN DOCUMENTS BY REFERENCE

         The following documents, heretofore filed by Authentidate Holding Corp.
with the Commission pursuant to the Exchange Act, are hereby incorporated by
reference, except as superseded or modified herein:

         1.       Our Annual Report on Form 10-K, as amended, for the fiscal
                  year ended June 30, 2001.

         2.       Our Quarterly Reports on Form 10-Q for the fiscal quarters
                  ended September 30, 2001, December 31, 2001 and March 31,
                  2002.

         3.       Our Reports on Form 8-K dated November 29, 2001, March 15,
                  2002, May 9, 2002, August 5, 2002 and August 6, 2002.

         4.       Our Proxy Statement for our Annual Meeting of Shareholders
                  held on January 24, 2002.


                                        1
<PAGE>
         5.       A description of our common stock contained in our
                  registration statement on Form 8-A filed April 17, 2000.

         Each document filed subsequent to the date of this prospectus pursuant
to Section 13(a), 13(c), 14 or 15(d) of the Exchange Act prior to the
termination of this offering shall be deemed to be incorporated by reference in
this prospectus and shall be part hereof from the date of filing of such
document.

         All documents filed by the registrant after the date of filing the
initial registration statement on Form S-8 of which this prospectus forms a part
and prior to the effectiveness of such registration statement pursuant to
Section 13(a), 13(c), 14 and 15(d) of the Securities Exchange Act of 1934 shall
be deemed to be incorporated by reference into this prospectus and to be part
hereof from the date of filing of such documents.

         We will provide without charge to each person to whom a copy of this
Prospectus is delivered, upon the written or oral request of any such person, a
copy of any document described above (other than exhibits). Requests for such
copies should be directed to Authentidate Holding Corp., 2165 Technology Drive,
Schenectady, New York 12308, telephone (518) 346-7799, Attention: Chief
Financial Officer.


                                        2
<PAGE>
                               PROSPECTUS SUMMARY

         The following summary is intended to set forth certain pertinent facts
and highlights from material contained in our Annual Report on Form 10-K, as
amended, for the fiscal year ended June 30, 2001, and our Reports on Form 10-Q,
for the fiscal quarters ended September 30, 2001, December 31, 2001 and March
31, 2002, incorporated by reference into this prospectus.

                           AUTHENTIDATE HOLDING CORP.

OUR BUSINESS

         Authentidate Holding Corp. ("AHC"), its subsidiaries DJS Marketing
Group, Inc. ("DJS"), Authentidate, Inc., and Trac Medical Solutions, Inc. (f/k/a
WebCMN, Inc.), and through its joint ventures Authentidate International, AG,
and Authentidate Sports, Inc. (f/k/a Authentidate Sports Edition, Inc.)
(sometimes collectively referred to herein as the "Company"), are engaged in the
following businesses:

         -        the manufacture and distribution of document imaging systems;

         -        the development and sale of software-based authentication
                  products; and

         -        the sale and integration of computer systems and related
                  peripheral equipment, components, and accessories and network
                  and internet services.

         AHC was formerly known as Bitwise Designs, Inc. The name change was
approved by our shareholders at the March 23, 2001 Annual Meeting.

         In March 1996, we acquired DJS (d.b.a Computer Professionals), a
systems integrator and computer reseller in Albany, New York. DJS is an
authorized sales and support provider for Novell, Microsoft Solutions and Lotus
Notes.

         We established our Authentidate subsidiary during the fiscal year ended
June 30, 2000 to engage in the business of providing end users with a service
providing for the storage, confirmation and authentication of electronic data
and images. Subsequent to the formation of Authentidate, we established with a
German entity Authentidate International, A.G., a German corporation, to market
the Authentidate service in certain foreign countries. As discussed below,
Authentidate International is now a wholly-owned subsidiary of AHC. Authentidate
Sports, Inc., established during the fiscal year ended June 30, 2001, as a joint
venture with Internet Venture Capital, LLC, a partner experienced in the sports
memorabilia industry, is developing a service that applies the Authentidate
technology to the field of signature authentication as it relates to sports
memorabilia and entertainment collectibles. Our subsidiary, Trac Medical
Solutions, Inc., is in the process of developing a business model to apply the
Authentidate technology to the medical supply business relating to the
automation and processing of Certificates of Medical Necessity.

PRODUCTS AND SERVICES

         Document Imaging Systems

         In January 1996 we introduced our document imaging management system on
a national


                                        3
<PAGE>
level under the tradename DocStar. Our DocStar product enables users to scan
paper documents onto an optical disk, hard drive or other storage medium from
which they can be retrieved in seconds. This system allows users to eliminate or
significantly reduce paper filing systems. We believe that a broad spectrum of
businesses and governmental agencies experience the problem of storage,
management and security of paper documents. The DocStar product line is intended
to provide a cost effective method of reducing the space necessary to store
documents while granting a user the ability to instantly retrieve documents.

         Authentication Software

         We have established the following subsidiaries and joint venture to
develop and sell software-based authentication services:

         -        Authentidate, Inc. - to provide a software-based service to
                  accept and store electronic files and date and time stamps
                  those files with a secure clock to prove content, date and
                  time authenticity;

         -        Authentidate International, A.G. - a wholly-owned subsidiary
                  to market the Authentidate service in certain foreign
                  countries;

         -        Authentidate Sports, Inc. - a joint venture established with
                  Internet Venture Capital, LLC, to develop an authentication
                  service based on our Authentidate technology for use in the
                  sports memorabilia and collectibles industries; and

         -        Trac Medical Solutions, Inc. - to develop a service based on
                  the Authentidate technology designed to facilitate the
                  processing of Certificates of Medical Necessity.

         Computer Products and Services

         Along with our subsidiary, DJS, we primarily market the following
different products and services:

         -        Computer Products and Integration Services;

         -        Network Services; and

         -        Internet/Intranet Development Services.

                              DOCSTAR PRODUCT LINE

         Our document imaging management system, marketed on a national level
under the tradename DocStar, enables users to scan paper documents onto an
optical disk, hard drive or other storage medium from which they can be
retrieved in seconds. We design and manufacture the DocStar product line, which
consists of a personal computer, proprietary software and may also include a
scanner. This system can be utilized as a "stand-alone" system or as part of a
network installation. We consider our DocStar division to be a software
business. While, we sell the hardware in order provide the customer with a
"turn-key" system, we believe that it is the software employed in the DocStar
system which differentiates us from our


                                        4
<PAGE>
competitors.

         The operation of a DocStar unit is similar to that of a facsimile and
scanning machine. Documents are fed into an optical scanner that reads the
documents and stores the information on one of several alternative mass storage
devices. Documents can also be transmitted from or to the system via facsimile
machine or modem. Documents can be retrieved almost instantaneously for viewing,
printing or faxing thereby offering a significant time-saving tool to the modern
office.

         We market our DocStar products through a national dealer network of
approximately 100 dealers and anticipate the addition of several new dealers in
future fiscal quarters to expand into markets not currently served. We own one
dealership in the Albany, New York region, which also serves as a test market
for new applications and software.

                           AUTHENTIDATE BUSINESS LINES

         In 1999, we established a majority owned subsidiary named Authentidate,
Inc., to engage in a new business line of providing end users with a
software-based service which will:

         -        accept and store electronic images from networks and personal
                  computers throughout the world and from different operating
                  systems via the Internet;

         -        indelibly date and time stamp all electronic images received
                  using a secure clock;

         -        allow users to transmit only the "secure codes" to
                  Authentidate fileservers while maintaining the original within
                  the customers "firewall"; and

         -        allow users to prove authenticity of time, date and content of
                  stored electronic documents.

THE AUTHENTIDATE SERVICE

         The Authentidate product, marketed as the Enterprise Edition, was
released for sale in May, 2001. We contemplate that product integration
development work will be necessary for many applications or customers. We are in
the process of selling this product and recorded revenue of approximately
$25,000 during the fiscal year ended June 30, 2002. We initially retained a
third party consulting firm, Cap Gemini America, Inc., to program and develop
the Enterprise Edition. Currently, we have employed our own staff of software
developers to improve the products.

RELATED ENTITIES

         AHC formed a joint venture in March, 2000, known as Authentidate
International, AG, with a German company to develop the Authentidate software in
foreign languages and to market that product outside the Americas, Japan,
Australia, New Zealand and India. This company is currently in the market
development stage. On March 15, 2002, we consummated the acquisition of the
outstanding capital stock of Authentidate International not owned by us and
presently own all of the capital stock of this company.


                                        5
<PAGE>
         AHC established Authentidate Sports, Inc., a joint venture with
Internet Venture Capital, LLC, an investor experienced in the sports memorabilia
industry, during the fiscal year ended June 30, 2001. Authentidate Sports (f/k/a
Authentidate Sports Edition, Inc.) was created to market Authentidate services
to the sports memorabilia and collectibles industries. This company is currently
in the market development stage.

         AHC established Trac Medical Solutions, Inc. as WebCMN, Inc., in March,
2001 in order to develop a service to facilitate the processing of Certificates
of Medical Necessity. WebCMN changed its corporate name to Trac Medical
Solutions, Inc., in connection with its acquisition of various intellectual
property and other assets in October, 2001, including the trademark "Trac
Medical" and a patent application related to the business model it is
developing. Certificates of Medical Necessity must be filed by suppliers seeking
government reimbursement in connection with the placement of medical devices.
Trac Medical Solutions intends to develop a software- based service
incorporating our proprietary Authentidate technology designed to facilitate the
processing of these documents to reduce the time period for reimbursement
currently experienced by suppliers of medical devices. This service is currently
in the development stage.

                            DJS MARKETING GROUP, INC.

         DJS (d/b/a "Computer Professionals") is a network and systems
integrator of computer and peripheral products for a variety of customers,
including corporations, schools, government agencies, manufacturers and
distributors. DJS is a prominent systems integrator in the Albany, New York
region.

         DJS provides network integration, Internet/Intranet development,
accounting solutions, service, consultation, document management and video
conferences. DJS also services the products it sells by employing factory
trained computer technicians and network engineers.

PRODUCTS AND SERVICES

         Computer Products and Integration Services

          DJS purchases personal computers and peripheral computer products from
many different suppliers. Peripheral computer products are products that operate
in conjunction with computers, including but not limited to, printers, monitors,
scanners, modems and software. DJS configures various computer hardware and
peripheral products such as software together, to satisfy a customer's
individual needs.

         Network Integration Services

         DJS' network integration group designs, implements, installs, manages
and supports enterprise networks with products from Novell, Microsoft, UNIX,
Tricord, Synoptics, Compaq, Cisco and others. Applications that the network
system provides include E-mail, accounting systems, word processing,
communication and any other applications that require the sharing of
information. DJS designs customized solutions for its clients with precise
objectives and its engineers analyze hardware, software, and cabling to ensure
effective and affordable solutions.


                                        6
<PAGE>
         Internet/Intranet Development

         DJS offers services related to the Internet, including Internet
connectivity, web page development, and hardware installation. Additionally, DJS
assists its clients through the buying and implementation process with
Internet/Intranet training and ongoing support.

         Service and Consultation

         DJS's service department is authorized to repair and maintain all major
brand products sold by DJS, including warranty and post-warranty equipment. DJS
generally guarantees a four (4) hour response time for all service calls, with
an average resolution time of next day.

         DJS's engineers also provide complete system configuration services,
which includes installation of all hardware, including memory, disk drives,
network or communication adapters, as well as any associated software or driver.
All units are thoroughly tested after configuration and all malfunctioning units
are eliminated.

         Document Management

         DJS also offers document imaging services which it believes is an
efficient and financially attainable alternative to conventional, costly paper
trails. Management believes digital documents can be stored, searched, retrieved
and edited in a fraction of the time with complete access to the network and
quality control features. Among other product lines, DJS offers customers our
DocStar line.

         Sales and Marketing

         DJS markets its products and services throughout New York State, parts
of Vermont and Massachusetts. DJS intends to expand its national and
international sales and marketing departments. Clients include corporations,
small office/home office owners, schools, government agencies, manufacturers and
distributors.

RECENT EVENTS

         Private Placement

         As of August 5, 2002, we have completed sales on an aggregate of
$2,000,035 in a private offering of our securities. The securities offered have
a purchase price of $3.03 per unit. We are offering a maximum of 1,584,158 units
in the private placement, each unit comprised of one share of common stock and
one warrant to purchase .20 shares of Common Stock. To date, we have sold an
aggregate of approximately 660,077 units.

         We have agreed to file a registration statement with the Securities and
Exchange Commission to register for resale the shares of common stock contained
in the units, including the shares underlying the warrants. In the event that we
do not timely file the registration statement, or it is not timely declared
effective, the investors will be entitled to liquidated damages equal to 2% of
the purchase price for each month that the relevant event is delayed.

         The proceeds of the financing will be used to increase the business
development, marketing and sales efforts for our services, along with our
general working capital needs. There can be no assurance that we will be able to
complete the maximum amount of the offering.


                                        7
<PAGE>
         The offering is intended to comply with Section 4 (2) of the Securities
Act of 1933 and/or Regulation D. Neither the units, shares or warrants have been
registered for offer or sale under the Securities Act; such securities are being
issued on the basis of the statutory exemption provided by Section 4(2) of the
Securities Act and/or Regulation D promulgated thereunder relating to
transactions by an issuer not involving any public offering. The transaction has
not been reviewed by, passed on or submitted to any Federal or state agency or
self-regulatory organization where an exemption is being relied upon. The
securities may not be sold, assigned or transferred unless (i) the sale,
assignment or transfer of such securities is registered under the Securities
Act, or (ii) the securities are sold, assigned or transferred in accordance with
all the requirements and limitations of Rule 144 under the Securities Act.

         U.S. Postal Service Contract

         On August 6, 2002, we announced that we entered into a strategic
alliance agreement with the United States Postal Service to be the provider of
the USPS Electronic Postmark(R) (EPM) service. Under the terms of the
non-exclusive agreement, our subsidiary, AuthentiDate, Inc., will provide the
management, technology and support for the United States Postal Service's EPM
system.

         The USPS Electronic Postmark(R) provides evidence that the content of a
document or file existed at a specific date and time, and the EPM is intended to
protect the integrity of the document or file by ensuring that it cannot be
altered without detection. The EPM uses patent pending technology offering
highly sophisticated encryption ensuring document authenticity and is intended
to be added to any application regardless of the computing platform or operating
system.

         The agreement, entered into on July 31, 2002, provides that
Authentidate and USPS will agree within thirty days of the effective date of the
Agreement for a plan for launching the EPM system. The initial term of the
agreement commences on the effective date and expires five years thereafter,
unless terminated as provided therein. Upon mutual agreement of the parties, the
agreement may be extended for three additional three-year terms, unless sooner
terminated. The aggregate term of the agreement shall in no event exceed a total
of fourteen years.

         The agreement may be terminated as follows:

                  -        By the mutual agreement of the parties;

                  -        By either party if one party materially breaches the
                           Agreement and such breach continues for a period of
                           thirty days after the date the non- breaching party
                           provides written notice of the breach.

                  -        By USPS, without penalty, at any time upon thirty
                           days written notice if regulatory, legislative or
                           judicial action or inaction occurs which
                           substantially impairs USPS's ability to perform its
                           obligations under this Agreement;

                  -        Commencing six months after the launch of the EPM
                           System, USPS may terminate the Agreement upon one
                           hundred eighty days written notice, for any reason;

                  -        We may, upon three hundred sixty days written notice,
                           terminate the


                                        8
<PAGE>
                           Agreement for any reason; and

                  -        USPS may terminate this Agreement by giving thirty
                           days' written notice to us in the event that there is
                           a change in control in Authentidate.

         The agreement provides for revenue sharing between the parties based
on gross revenues.

         Pursuant to the terms of the Agreement, we will develop, integrate,
operate, host and maintain all elements of the EPM system. More specifically, we
will provide the staff and resources as necessary to support the EPM
development, operation and promotion efforts; enable EPM to interoperate with
products or systems used by customers; implement billing and accounting systems
to ensure prompt and efficient aggregation of gross revenues and to support
prompt payment of gross revenues; provide customer support; and implement the
sale and marketing of the EPM system.

         USPS shall support the EPM system as follows:

                  -        USPS will pay a total of $250,000 to Authentidate
                           provided that neither Authentidate Holding Corp. nor
                           Authentidate are in default under this Agreement;

                  -        provide necessary access to technical personnel and
                           information to assist in the development efforts for
                           program management, on-site security inspection, and
                           USPS certification and accreditation; and

                  -        promote the EPM system on USPS.com and provide
                           hyperlinks in accordance with standard USPS practice,
                           use its best efforts to identify potential corporate
                           and government customers, participate in strategic
                           sales efforts to acquire customers, issue public
                           announcements and press releases, send appropriate
                           USPS representatives for events, press tours,
                           interviews, and speaking engagements, provide
                           introductions to USPS contract public relations and
                           advertising agency firms and acknowledge
                           Authentidate's role in providing the EPM System for
                           any and all promotional and marketing purposes.

         Zylab International Transaction

         On January 9, 2002, we announced that we have entered into a letter of
intent to acquire the assets of Zylab International, Inc., a privately owned
company based in Germantown, Maryland for shares of AHC common stock. The letter
of intent contemplated that the purchase price will range between a minimum of
725,000 and a maximum of 1,000,000 shares of AHC common stock. The precise
number of shares to be issued as the purchase price was to be determined prior
to closing. The parties are negotiating potential alternative transactions which
may result in termination of the letter of intent. Pursuant to the letter of
intent, we loaned to Zylab an aggregate principle amount of $500,000

                                        9
<PAGE>
, which loan is collateralized by all of the assets of Zylab,
including its intellectual property. The acquisition is subject to various terms
and conditions, including the completion of the due diligence investigation, the
negotiation of a definitive agreement and the approval of the respective boards
and Zylab's shareholders. Accordingly, there can be no assurance that the
transaction will be consummated. As of the date of this prospectus, the
transaction has not been consummated and we are negotiating with Zylab the terms
of pursuant to which they will repay our loan.

OUR OFFICES

         We were initially organized in August 1985 and reincorporated under the
laws of the state of Delaware in May 1992. Our executive offices are located at
2165 Technology Drive, Schenectady, New York 12308, our telephone number is
(518) 346-7799, and our Internet address is www.authentidatehc.com.


                                       10
<PAGE>
                                  THE OFFERING

<TABLE>
<S>                                                  <C>
Common Stock Offered by the
Selling Security Holders.........................    500,000

Common Stock Outstanding
  Prior to Offering (1) ...........................  19,969,480

Common Stock Outstanding
  After the Offering (2) .........................   20,469,480

Use of Proceeds...................................   Authentidate Holding Corp. will not receive any
                                                     proceeds from the sales of the Selling Shareholders.
                                                     We anticipate that proceeds received from the
                                                     exercise of any options will be used for working
                                                     capital and general corporate purposes. Please see
                                                     "Use of Proceeds."

Nasdaq National Market Symbol
(Common Stock):                                      "ADAT"
</TABLE>


- --------------------

(1) Based on the number of shares actually outstanding as of August 6, 2002.

Unless otherwise specifically stated, information throughout this prospectus
excludes as of August 6, 2002:

- - 3,000,000 shares of Common Stock reserved for issuance under our 1992 Employee
Stock Option Plan, of which 1,339,742 shares have been reserved for currently
outstanding options;

- - 5,000,000 shares of Common Stock reserved for issuance under our 2000 Employee
Stock Option Plan, of which 2,807,357 shares have been reserved for currently
outstanding options;

- - 160,000 shares of Common Stock reserved for currently outstanding options
under our 1992 Director Plan;

- - 2,817,833 shares of Common Stock reserved for issuance upon the exercise of
currently outstanding warrants;

- - 373,333 shares of Common Stock reserved for issuance upon the conversion of
our Series B Preferred Stock; and

- - 825,593 shares of Common Stock reserved for issuance upon the conversion of
our Series C Preferred Stock.

(2) This assumes the exercise and conversion of all of securities for which
underlying shares are being registered.


                                       11
<PAGE>
                                  RISK FACTORS

         An investment in the securities offered hereby involves a high degree
of risk. The following factors, in addition to those discussed elsewhere, should
be considered carefully in evaluating us and our business. An investment in the
securities is suitable only for those investors who can bear the risk of loss of
their entire investment.

IF WE CONTINUE TO FACE UNCERTAINTIES IN MARKETING THE DOCSTAR SYSTEM AND
AUTHENTIDATE PRODUCT, WE MAY CONTINUE TO LOSE MONEY.

         We incurred losses of $9,340,103, $5,274,043 and $3,166,488 for the
fiscal years ended June 30, 2001, 2000 and 1999, respectively, and losses of
$2,533,384, $2,222,955 and $2,608,970 for the quarters ended March 31, 2002,
December 31, 2001 and September 30, 2001, respectively. We have incurred
significant costs developing our Authentidate services and will continue to
incur these costs in the future as we attempt to increase market awareness and
sales. We have also incurred significant costs to date in establishing and
maintaining the distribution channels for our DocStar products and will continue
to incur such costs in the future. In the event we determine to expand our
distribution channels, these costs would be expected to increase. Our prospects
should be considered in light of the difficulties frequently encountered in
connection with the establishment of a new business line and the competitive
environment in which we operate. There can be no assurance that we will be able
to achieve profitable operations in future operating periods.

WE HAVE LIMITED WORKING CAPITAL AND MAY NEED ADDITIONAL FUNDS TO FINANCE FUTURE
OPERATIONS.

         Our capital requirements have been and will continue to be significant.
We have been substantially dependent upon public offerings and private
placements of our securities and on short-term and long-term loans from lending
institutions to fund such requirements. We are expending significant amounts of
capital to promote and market the Authentidate product line, including the
offerings of our Trac Medical Solutions subsidiary and our Authentidate Sports
venture, and continue to promote our DocStar products. Due to these
expenditures, we have incurred significant losses to date. During the nine
months ended March 31, 2002 and for the fiscal year ended June 30, 2001, we used
$4,823,052 and $1,391,651 in cash from operating activities, respectively. We
have capitalized the software development costs relating to our new Authentidate
product and our ability to recover such costs is highly dependent on the future
success of the marketing and sales of this product. If the revenue generated
from our Authentidate product is less than anticipated, the carrying value of
the software development costs may be impaired and require an impairment charge
in the future.

         As described on page 8 of this prospectus, we closed on an aggregate of
$2,000,035 of our equity securities in a private placement pursuant to Section
4(2) of the Securities Act of 1933, as amended, and Regulation D, promulgated
thereunder. While we are offering a maximum of $4,800,000 of our securities in
the private placement, there can be no guarantee that we will close on any
additional funds in this offering. We expect the net proceeds currently received
from this offering to satisfy our cash needs for an additional six months. If we
close on the maximum offering, we expect the net proceeds to satisfy our cash
needs for twelve months. In the future, we may need additional funds from loans
and/or the sale of equity securities to fully implement our business plans. No
assurance can be given that such funds will be available or, if


                                       12
<PAGE>
available, will be on commercially reasonable terms satisfactory to us. In the
event such funds are not available, we will be forced to reduce our current and
proposed operations.

WE HAVE INCURRED SIGNIFICANT ADDITIONAL COSTS CONCERNING OUR INTERNATIONAL
OPERATIONS AND MAY INCUR ADDITIONAL COSTS IN THE FUTURE.

         On March 15, 2002, we consummated a transaction to acquire all of the
outstanding capital shares of Authentidate International, AG held by our
co-venturers. Pursuant to the Stock Purchase Agreement, we repurchased all of
the outstanding shares of Authentidate International in exchange for an
aggregate of 1,425,875 shares of our common stock and warrants to purchase
100,000 shares of our common stock. In connection with this transaction, certain
of the sellers also surrendered to us for cancellation an aggregate of 250,000
warrants to purchase shares of our common stock which were previously issued to
them. In connection with this transaction, we made a $500,000 loan to
Authentidate International as of December 24, 2001. Our ability to collect on
the loan will be dependent upon the profitability of Authentidate International.
There can be no assurances, however, that Authentidate International will
achieve profitability. We may incur additional expenses in subsequent to the
consummation of the proposed transaction in operating Authentidate International
as a wholly-owned subsidiary of our company. Further, we entered into an
employment agreement with Mr. Jan C.E. Wendenburg, pursuant to which Mr.
Wendenburg will serve as the Chief Executive Officer of Authentidate
International, AG, for a three year term. In consideration of his services, Mr.
Wendenburg will receive an initial base salary of US$200,000 and options to
purchase 184,000 shares of our common stock. We will also issue additional stock
options to other employees of Authentidate International, AG.

WE MAY ACQUIRE ADDITIONAL COMPANIES WHICH MAY RESULT IN ADVERSE EFFECTS ON OUR
EARNINGS AND WHICH MAY ADVERSELY AFFECT OUR MANAGEMENT AND OPERATING SYSTEMS.

         As described above, we have consummated the transaction to acquire
Authentidate International, AG and have been negotiating the terms of an
additional acquisition, as described on page 9 of this prospectus. Any
acquisition that we may consummate may have an adverse effect on our liquidity
and earnings and may be dilutive to our earnings. Further, in the event that we
consummate an acquisition or obtain additional capital through the sale of debt
or equity to finance an acquisition, our shareholders may experience dilution in
their shareholders' equity. Additionally, by growing through acquiring other
companies, significant demands are being made on our management, operations and
resources, including working capital. If we are not able to effectively manage
our growth, our business and operations will be materially harmed. To manage
growth effectively, we will be required to continue to improve our operational,
financial and managerial systems, procedures and controls, hire and train new
employees while managing our current operations and employees.

THE GRANT WE RECEIVED IN CONNECTION WITH THE CONSTRUCTION OF OUR HEADQUARTERS
REQUIRES US TO ATTAIN CERTAIN THRESHOLDS, THE ATTAINMENT OF WHICH MAY
SIGNIFICANTLY INCREASE OUR OPERATING COSTS.

         In June 1999, we completed construction of a new office and production
facility in Schenectady, New York for approximately $2,300,000, which was
financed with a $1,000,000 grant from the Empire State Development Corporation
(an agency of New York state) and a mortgage loan from a local financial
institution. The grant stipulates that we are obligated to achieve certain
annual employment levels between January 2002 and January 2006. While we


                                       13
<PAGE>
have not currently achieved the agreed upon employment levels, we expect to
achieve such levels by 2006. In order to achieve the employment levels required
by the grant, we would incur substantial additional operating costs in
connection with the salaries and benefits to be received by the additional
employees. In the event we do not achieve the stipulated employment levels, some
or all of the grant will have to be repaid. Accordingly, the grant has been
classified as a long term liability on our balance sheet. In the event some or
all of the grant will be required to be repaid, we will either seek refinancing
from a financial institution, sell the building or pay the amounts due out of
our cash reserves.

OUR PRODUCTS MAY NOT BE ACCEPTED BY OUR CONSUMERS WHICH WOULD SERIOUSLY HARM OUR
BUSINESS.

         Although we introduced our DocStar imaging system products on a
national level in January 1996, demand and market acceptance for the DocStar
imaging system remains subject to a high level of uncertainty. Achieving
widespread acceptance of this product line will continue to require substantial
marketing efforts and the expenditure of significant funds to create brand
recognition and customer demand for such products. There can be no assurance
that adequate marketing arrangements will be made for such products. The
Authentidate product line is a new product line and there can be no assurance
that these products will ever achieve widespread market acceptance or increased
sales or that the sale of such products will be profitable.

IF WE CANNOT CONTINUOUSLY ENHANCE OUR PRODUCTS IN RESPONSE TO RAPID CHANGES IN
THE MARKET, OUR BUSINESS WILL BE HARMED.

         The computer industry and software-based services industry are
characterized by extensive research and development efforts which result in the
frequent introduction of new products which render existing products obsolete.
Our ability to compete successfully in the future will depend in large part on
our ability to maintain a technically competent research and development staff
and our ability to adapt to technological changes in the industry and enhance
and improve existing products and successfully develop and market new products
that meet the changing needs of our customers. Although we are dedicated to
continued research and development of our products with a view towards offering
products with the most advanced capabilities, there can be no assurance that we
will be able to continue to develop new products on a regular basis which will
be competitive with products offered by other manufacturers. At the present
time, we do not have a targeted level of expenditures for research and
development. We will evaluate all opportunities but believe the majority of our
research and development will be devoted to enhancements of our existing
products.

         Technological improvements in new products that we and our competitors
offer, which, among other things, results in the rapid decline of the value of
inventories, as well as the general decline in the economy and other factors,
have resulted in recent declines in retail prices for computer products. As
competitive pressures have increased, many companies have ceased operation and
liquidated inventories, further increasing downward pricing pressure. Such
declines have, in the past, and may in the future, reduce our profit margins.

WE DO NOT HAVE PATENTS ON ALL THE TECHNOLOGY WE USE WHICH COULD HARM OUR
COMPETITIVE POSITION.


                                       14
<PAGE>
         We do not currently hold any patents and the technology embodied in
some of our current products cannot be patented. We have four patents pending
for the innovative technology underlying the Authentidate business plan that can
verify the authenticity of digital images by employing a secure clock to stamp
the date and time on each image captured and have one patent pending concerning
the associated business process. We recently acquired the rights to an
additional patent application related to our Trac Medical Solutions, Inc.,
business model. We have also registered as trademarks the logos "DocStar" and
"Authentidate" and acquired the registered trademark "Trac Medical". We rely on
confidentiality agreements with our key employees to the extent we deem it to be
necessary. We further intend to file a patent application for any new products
we may develop, to the extent any technology included in such products is
patentable, if any. There can be no assurance that any patents in fact, will be
issued or that such patents will be effective to protect our products from
duplication by other manufacturers. In addition, there can be no assurance that
any patents that may be issued will be effective to protect our products from
duplication by other developers.

         Other companies operating within our business segment may independently
develop substantially equivalent proprietary information or otherwise obtain
access to our know-how. In addition, there can be no assurance that we will be
able to afford the expense of any litigation which may be necessary to enforce
our rights under any patent. Although we believe that the products we sell do
not and will not infringe upon the patents or violate the proprietary rights of
others, it is possible that such infringement or violation has or may occur. In
the event that products we sell are deemed to infringe upon the patents or
proprietary rights of others, we could be required to modify our products or
obtain a license for the manufacture and/or sale of such products. There can be
no assurance that, in such an event, we would be able to do so in a timely
manner, upon acceptable terms and conditions, or at all, and the failure to do
any of the foregoing could have a material adverse effect upon our business.
Moreover, there can be no assurance that we will have the financial or other
resources necessary to enforce or defend a patent infringement or proprietary
rights violation action. In addition, if our products or proposed products are
deemed to infringe upon the patents or proprietary rights of others, we could,
under certain circumstances, become liable for damages, which could also have a
material adverse effect on our business.

WE DEPEND ON OTHERS FOR COMPONENTS OF OUR PRODUCTS, WHICH MAY RESULT IN DELAYS
AND QUALITY-CONTROL ISSUES.

         We do not own or lease any manufacturing facilities and do not
manufacture any of the component parts for our products. Rather, we purchase all
of these components from unaffiliated suppliers. All of our products are
assembled at our facilities. We believe that at the present time we have
sufficient sources of supply of component parts, and that in the event any
existing supplier ceases to furnish component parts to us, alternative sources
are available. However, there can be no assurance that the future production
capacity of our current suppliers and manufacturers will be sufficient to
satisfy our requirements or that alternate suppliers and manufacturers will be
available on commercially reasonable terms, or at all. Further, there can be no
assurance that the availability of such supplies will continue in the future.

IF OUR PRODUCTS ARE NOT COMPETITIVE, OUR BUSINESS WILL SUFFER.

         Authentidate Holding Corp. and its subsidiaries are engaged in the
highly competitive


                                       15
<PAGE>
businesses of assembling and distributing document imaging systems,
software-based authentication products, computer hardware and software as well
as technical support services for such businesses. The document imaging business
is competitive and we compete with major manufacturers. Many of these companies
have substantially more experience, greater sales, as well as greater financial
and distribution resources than do we. The most significant aspects of
competition are the quality of products, including advanced capabilities, and
price. There can be no assurance that we can effectively continue to compete in
the future.

         Our Authentidate business is a new business line and the level of
competition is unknown at this point in time. There can be no assurances,
however, that Authentidate products will achieve market acceptance.

         Our DJS subsidiary is engaged in the highly competitive business of
systems integration, computer services and computer reselling. DJS competes with
many small and local companies which provide similar technical services to those
offered by DJS. Additionally, DJS must compete with other computer resellers,
many of whom have greater financial and technical resources. There can be no
assurance that DJS will be able to compete successfully with these competitors.

IF WE LOSE OUR PRESIDENT, OUR BUSINESS WILL BE HARMED.

         Our success is largely dependent upon the services of our Chairman of
the Board and President, John T. Botti. The loss of his services would have a
material adverse affect on our business and prospects. We have entered into a
three-year employment agreement with Mr. Botti expiring in January, 2003. We
have obtained, for our benefit, "key man" life insurance in the amount of
$1,000,000 on Mr. Botti's life.

SINCE WE HAVE NOT PAID DIVIDENDS ON OUR COMMON STOCK, YOU MAY NOT RECEIVE INCOME
FROM THIS INVESTMENT.

         We have not paid any dividends on our Common Stock since our inception
and do not contemplate or anticipate paying any dividends on our Common Stock in
the foreseeable future. Earnings, if any, will be used to finance the
development and expansion of our business.

IF OUR COMMON STOCK IS DELISTED FROM NASDAQ, LIQUIDITY IN OUR COMMON STOCK MAY
BE AFFECTED.

         Our Common Stock is listed for trading on the Nasdaq National Market.
In order to continue to be listed on Nasdaq, however, we must meet certain
criteria, including one of the following:

         -        maintaining $4,000,000 in net tangible assets, a minimum bid
                  price of $1.00 per share and a market value of its public
                  float of $5,000,000; or

         -        having a market capitalization of at least $50,000,000, a
                  minimum bid price of $5.00 per share and a market value of its
                  public float of $15,000,000.

         On August 5, 2002, our closing bid price was $4.06. The dilution to our
shareholders which could be caused by the widespread conversion of the Series B
and Series C Preferred


                                       16
<PAGE>
Stock could cause the per share value of our common stock to drop below the
minimum bid of $1.00 required for continued listing. As of March 31, 2002, we
had net tangible assets of approximately $7,618,437 and as of March 29, 2002 the
market value of our public float was approximately $82,524,998.

         In the future, if we should fail to meet Nasdaq maintenance criteria,
our Common Stock may be delisted from Nasdaq, and trading, if any, in our
securities would thereafter be conducted in the non-Nasdaq over-the-counter
market. As a result of such delisting, an investor could find it more difficult
to dispose of, or to obtain accurate quotations as to the market value of, our
securities.

         Although we anticipate that our Common Stock will continue to be listed
for trading on Nasdaq, if the Common Stock were to become delisted from trading
on Nasdaq and the trading price of the Common Stock was below $5.00 per share on
the date the Common Stock was delisted, trading in such securities would also be
subject to the requirements of certain rules promulgated under the Exchange Act,
which require additional disclosure by broker-dealers in connection with any
trades involving a stock defined as a penny stock (generally, any non-Nasdaq
equity security that has a market price of less than $5.00 per share, subject to
certain exceptions). Such rules require the delivery, prior to any penny stock
transaction, of a disclosure schedule explaining the penny stock market and the
risks associated therewith, and impose various sales practice requirements on
broker-dealers who sell penny stocks to persons other than established customers
and accredited investors (generally institutions). For these types of
transactions, the broker-dealer must make a special suitability determination
for the purchaser and have received the purchaser's written consent to the
transaction prior to sale. The additional burdens imposed upon broker-dealers by
such requirements may discourage broker-dealers from effecting transactions in
our securities, which could severely limit the market price and liquidity of
such securities and the ability of purchasers to sell their securities in the
secondary market.

OUR SERIES B PREFERRED STOCK FINANCING MAY RESULT IN DILUTION TO OUR COMMON
SHAREHOLDERS.

         Dilution of the per share value of our common shares could result from
the conversion of most or all of the Series B Preferred Stock we sold in a
private placement in October 1999. Holders of our Series B Preferred Stock may
convert these shares into shares of our common stock at a conversion price of
$1.875 beginning one year after the issuance of the Series B Preferred Stock.
However, after three years from the closing, the conversion price is subject to
a floating rate equal to the lower of $1.875 or the average of the closing bid
and asked prices of our common stock for the immediately preceding ten
consecutive trading days ending one day prior to the notice of conversion;
provided, however, that the conversion price may not be lower than $0.875. As of
August 5, 2002, there are 28,000 shares of Series B Preferred Stock outstanding.

         The following chart presents the maximum number of common shares
issuable on conversion of the currently outstanding shares of Series B Preferred
Stock based on different conversion rates. While we expect to issue a maximum of
an additional 373,333 shares of common stock upon conversion of the Series B
Preferred Stock until October 5, 2002, we could issue a significantly greater
number of common shares upon conversion of the Series B Preferred Stock after
October 5, 2002, when the floating conversion rate is triggered.


                                       17
<PAGE>
<TABLE>
<CAPTION>
==============================================================================================
                                                                  Percentage of Total Shares
Conversion           Conversion      Maximum Number of Shares         of Common Stock
Period                  Rate         of Common Stock Issuable           Outstanding
==============================================================================================
<S>                  <C>             <C>                          <C>
10/6/2000 -            $1.875                373,333                       1.9%
10/5/2002
- ----------------------------------------------------------------------------------------------
10/6/2002 -            $1.875                373,333                       1.9%
- ----------------------------------------------------------------------------------------------
10/6/2002 -            $ 1.50                466,667                       2.4%
- ----------------------------------------------------------------------------------------------
10/6/2002 -            $ 1.00                700,000                       3.5%
- ----------------------------------------------------------------------------------------------
10/6/2002 -            $0.875                800,000                       4.0%
==============================================================================================
</TABLE>

         Regardless of the date of exercise, dilution could occur from the
widespread conversion of the Series B Preferred Stock. The following scenarios
could result in dilution to our common shareholders:

         -        In either period, the conversion price could be lower than the
                  actual trading price on the day of conversion. This could
                  result in the holder immediately selling all of its converted
                  common shares, which would have a dilutive effect on the value
                  of the outstanding common shares.

         -        After three years, if the average trading price falls below
                  $1.875, the lower the average trading price, the greater the
                  number of common shares that a holder of our Series B
                  Preferred Stock will receive upon conversion; provided,
                  however, that the conversion price may not be lower than
                  $0.875. This might further encourage the holders of the Series
                  B Preferred Stock to covert their shares into common shares.
                  The increased number of common shares would further depress
                  the average trading price of our common stock.

         -        The significant downward pressure on the trading price of our
                  common stock as Series B Preferred Stock holders converted
                  these securities and sell the common shares received on
                  conversion could encourage short sales by the holders of
                  Series B Preferred Stock or other shareholders. This would
                  place further downward pressure on the trading price of our
                  common stock. Even the mere perception of eventual sales of
                  common shares issued on the conversion of the Series B
                  Preferred Stock could lead to a decline in the trading price
                  of our common stock.

OUR SERIES C PREFERRED STOCK FINANCINGS MAY RESULT IN DILUTION TO OUR COMMON
SHAREHOLDERS.

         Dilution of the per share value of our common shares could result from
the conversion of most or all of the Series C Preferred Stock we sold in two
transactions pursuant to Regulation S to non-U.S. entities in May, 2001. Holders
of our Series C Preferred Stock may convert these shares into shares of our
common stock at a fixed conversion price of $4.845 beginning at the earlier of
one year after the issuance of the Series C Preferred Stock or upon the
effectiveness of a registration statement covering such shares. In addition, the
purchasers in these transactions received warrants to purchase such number of
shares of our common


                                       18
<PAGE>
stock as equals 10% of the number of shares issuable upon conversion of the
Series C Preferred Stock, rounded up to the nearest 1,000 shares. The warrants
may not be exercised until the earlier of one year from the date of issuance or
upon the effectiveness of a registration statement covering the Common Stock
underlying the warrants. We initially issued 5,500 shares of Series C Preferred
Stock which are convertible into an aggregate of 1,135,191 shares of Common
Stock and 114,000 warrants. As of the date of this prospectus, there are
outstanding 4,000 shares of Series C Preferred Stock which are convertible into
an aggregate of 825,593 shares of Common Stock and 114,000 warrants.

WE HAVE SOLD RESTRICTED SHARES WHICH MAY DEPRESS OUR STOCK PRICE WHEN IT IS
SELLABLE UNDER RULE 144.

         As of August 5, 2002, there were 2,933,237 shares of Common Stock
currently outstanding may be deemed "restricted securities" as that term is
defined under the Securities Act of 1933 (the "Act"), and in the future, may be
sold pursuant to a registration under the Act, in compliance with Rule 144 under
the Act, or pursuant to another exemption therefrom. Rule 144 provides, that, in
general, a person holding restricted securities for a period of one year may,
every three months thereafter, sell in brokerage transactions an amount of
shares which does not exceed the greater of one percent of our then outstanding
Common Stock or the average weekly trading volume of the Common Stock during the
four calendar weeks prior to such sale. Rule 144 also permits, under certain
circumstances, the sale of shares without any quantity limitations by a person
who is not an affiliate of ours and was not an affiliate at any time during the
90 day period prior to sale and who has satisfied a two year holding period.
Sales of our Common Stock by certain present stockholders under Rule 144 may, in
the future, have a depressive effect on the market price of our securities. In
addition, the sale of shares by officers and directors and other affiliated
shareholders, may also have a depressive effect on the market for our
securities.

OUR OUTSTANDING OPTIONS AND WARRANTS MAY DEPRESS OUR STOCK PRICE.

         As of August 5, 2002, there were outstanding stock options to purchase
an aggregate of 4,307,099 shares of Common Stock at exercise prices ranging from
$0.01 to $9.125 per share, not all of which are immediately exercisable. As of
August 5, 2002 there were outstanding immediately exercisable warrants to
purchase an aggregate of 2,817,833 shares of Common Stock at exercise prices
ranging from $1.00 to $13.04 per share. In addition, there are outstanding
28,000 shares of our Series B Preferred Stock, which are currently convertible
into an aggregate of 373,333 Shares of Common Stock and 4,000 shares of our
Series C Preferred Stock, which are convertible into an aggregate of 825,593
shares of Common Stock. To the extent that outstanding stock options and
warrants are exercised or the Series B and Series C Preferred Stock is
converted, dilution to our shareholders will occur. Moreover, the terms upon
which we will be able to obtain additional equity capital may be adversely
affected, since the holders of the outstanding options and warrants can be
expected to exercise or convert them at a time when we would, in all likelihood,
be able to obtain any needed capital on terms more favorable to us than the
exercise and conversion terms provided by the outstanding options, warrants and
preferred stock.

IF WE CANNOT OFFSET FUTURE TAXABLE INCOME OUR TAX LIABILITIES WILL INCREASE.

         At June 30, 2001, the date of the most recent fiscal year end for which
we have


                                       19
<PAGE>
calculated this amount, we had net operating loss carryforwards ("NOLS") for
federal income tax purposes of approximately $28,100,000 available to offset
future taxable income. Under Section 382 of the Internal Revenue Code of 1986,
as amended, utilization of prior NOLS is limited after an ownership change, as
defined in Section 382, to an annual amount equal to the value of the
corporation's outstanding stock immediately before the date of the ownership
change multiplied by the federal long-term exempt tax rate. Use of our NOLS
could also be limited as a result of grants of stock options under stock option
plans and other events. In the event we achieve profitable operations, any
significant limitation on the utilization of NOLS would have the effect of
increasing our current tax liability.

SINCE THE HOLDERS OF OUR OUTSTANDING SERIES A PREFERRED STOCK CONTROL OUR BOARD
OF DIRECTORS, OTHER SHAREHOLDERS MAY NOT BE ABLE TO INFLUENCE OUR DIRECTION.

         Our Certificate of Incorporation authorizes our Board of Directors to
issue up to 5,000,000 shares of Preferred Stock, from time to time, in one or
more series. The Board of Directors is authorized, without further approval of
the stockholders, to fix the dividend rights and terms, conversion rights,
voting rights, redemption rights and terms, liquidation preferences, and any
other rights, preferences, privileges and restrictions applicable to each new
series of Preferred Stock. We previously established 200 shares of Series A
Preferred Stock which are owned by John Botti and Ira Whitman, our founders and
officers. Currently there are only 100 shares of Series A Preferred Stock
outstanding, all of which are owned by Mr. Botti. The Series A Preferred Stock
entitles the holders to elect a majority of the Board of Directors. The
existence of such stock could adversely affect the voting power of the holders
of Common Stock and, under certain circumstances, make it more difficult for a
third party to gain control of us, discourage bids for the Common Stock at a
premium, or otherwise adversely affect the market price of the Common Stock. In
connection with our recent sale of Series C Preferred Stock, the holder of the
Series A Preferred Stock agreed not to exercise these rights unless we are
current in meeting our dividend obligations and the shares of Common Stock
issuable upon conversion or payable as dividends are not restricted from public
distribution in the United States. As of August 5, 2002, there are outstanding
4,000 shares of our Series C Preferred Stock. In addition, we issued 50,000
shares of our Series B Preferred Stock in our October, 1999 private offering, of
which 28,000 shares are outstanding as of August 5, 2002.

                                 USE OF PROCEEDS

         We will not receive any of the proceeds from the sale of the common
stock offered hereby, but will receive proceeds from the exercise of stock
options issued under the Non- Executive Director Plan. Any funds received in
connection with the exercise of these securities will be used for working
capital purposes.


                                       20
<PAGE>
                            SELLING SECURITY HOLDERS

         The shares offered for resale under this Re-offer Prospectus are being
registered for reoffers and resales by selling stockholders of Authentidate
Holding Corp. who have and may in the future acquire such shares under the 2001
Non-Executive Director Stock Option Plan. Such persons may resell all, a
portion, or none of such shares. The selling stockholders named below are
directors of Authentidate Holding Corp. who may acquire shares of common stock
under the 2001 Non-Executive Director Stock Option Plan and are eligible to
resell any such shares of common stock, regardless of whether they have any
present intent to do so.

<TABLE>
<CAPTION>
                                                                                SHARES/OPTION          PERCENTAGE OF
                                 SHARES/OPTION SHARES           OPTION             SHARES                 SHARES
         NAME OF                  BENEFICIALLY OWNED             SHARES          OWNED AFTER            OWNED AFTER
 SELLING SECURITY HOLDER(2)       PRIOR TO OFFERING (4)         OFFERED (3)        OFFERING             OFFERING (1)
<S>                             <C>                            <C>               <C>                   <C>
J. Edward Sheridan                     0/50,000                   10,000            0/50,000                  **
Charles C. Johnston                  48,570/70,000                10,000          48,570/70,000               **
Steven Kriegsman                       0/40,000                   10,000            0/40,000                  **
</TABLE>


- ------------------------------
**       Percentage is less than 1%.

(1)      Percentage based on 20,469,480 shares outstanding.

(2)      Each holder is a non-executive director of Authentidate Holding Corp.

(3)      Shares offered pursuant to this prospectus are underlying options to be
         granted to listed holders as of September 1, 2002. Each listed holder
         will be granted options to purchase 10,000 shares as of September 1,
         2002, pursuant to the terms of the 2001 Non-Executive Director Stock
         Option Plan.

(4)      Listed amounts do not include shares underlying options to be granted
         as described in note 3, above.

         The 2001 Director Plan is administered by the Board or a committee of
the Board (the "Committee") which shall at all times consist of not less than
two officers of Authentidate who are not entitled to participate in the 2001
Director Plan, to be appointed by the Board and to serve at the pleasure of the
Board. Options are granted only to non-executive directors serving on the Board
and Advisors serving on the Advisory Boards of Authentidate. The 2001
Non-Executive Director Plan was approved by the Board of Directors and submitted
to and approved by the shareholders at the Annual Meeting held on January 24,
2002.

         Under the 2001 Non-Executive Director Plan, each new non-executive
director to the Board of Directors is entitled to receive an Option to purchase
20,000 shares of Common Stock. Commencing on September 1, 2002, an Option to
purchase 10,000 shares of Common Stock will be granted to each non-executive
director and thereafter on September 1st of each year, pro rata, based on the
time the director has served in such capacity during the previous year. Each
person who is appointed as an Advisor on an Advisory Board established or
maintained by Authentidate shall, upon such appointment and on each anniversary
of the effective date of his appointment, receive an option to purchase 5,000
shares of our Common Stock. Advisors who are also chairmen of such Advisory
Board may be granted options to purchase 7,500 shares, on the terms and
conditions set forth herein.

         It is the intent of Authentidate that the 2001 Non-Executive Director
Plan and any award granted thereunder satisfy and be interpreted in a manner
that satisfies the applicable requirements of Rule 16b-3. This is so that such
persons will be entitled to the benefits of Rule 16b-3 or other exemptive rules
under Section 16 of the 1934 Act and will not be subjected to liability
thereunder.


                                       21
<PAGE>
                              PLAN OF DISTRIBUTION

         The common stock covered by this prospectus, including the shares
underlying the options which will be issued by Authentidate Holding Corp. upon
the exercise of such securities by the holders thereof, may be offered and sold
from time to time by the selling security holders, and pledgees, donees,
transferees or other successors in interest selling shares received after the
date of this prospectus from the selling security holders as a pledge, gift or
other non-sale related transfer. The shares of common stock covered by this
prospectus may be sold from time to time directly by any selling security holder
or any transferees, or alternatively, through underwriters, broker-dealers or
agents, including in one or more of the following transactions:

- -        on the Nasdaq Stock Market;

- -        on the over the counter market;

- -        in transactions other than on the Nasdaq Stock Market or over the
         counter market, such as private resales;

- -        in connection with short sales;

- -        by pledge to secure debts and other obligations;

- -        in connection with the writing of options, in hedge transactions, and
         in settlement of other transactions in standardized or over-the-counter
         options;

- -        in a combination of any of the above transactions; or

- -        pursuant to Rule 144 under the Securities Act, assuming the
         availability of an exemption from registration.

         The selling security holders may sell their shares at market prices
prevailing at the time of sale, at prices related to prevailing market prices,
at negotiated prices, or at fixed prices. In addition, such sales may be
effected in transactions which may involve block trades or transactions in which
the broker acts as agent for the seller and the buyer.

         In connection with sales of the shares of common stock, any selling
security holder may:

- -        enter into hedging transactions with broker-dealers, which may in turn
         engage in short sales of the shares of common stock issuable upon the
         exercise of the options in the course of hedging the positions they
         assume;

- -        sell short and deliver shares of common stock issuable upon the
         exercise of the options to close out the short positions; or

- -        loan or pledge shares of common stock issuable upon the exercise of the
         options to broker-dealers that in turn may sell the securities.

         The selling security holders and any broker-dealers, agents or
underwriters that participate with the selling security holders in the
distribution of the shares of common stock covered by this prospectus may be
deemed to be "underwriters" within the meaning of the Securities Act, in which
event any commissions received by these broker-dealers, agents or underwriters
and any profits realized by the selling security holders on the resales of the
shares may be deemed to be underwriting commissions or discounts under the
Securities Act. Broker-dealers that are used to sell shares will either receive
discounts or commissions from the selling security holders, or will receive
commissions from the purchasers for whom they acted as agents. The selling
security holders may agree to indemnify any broker-dealer or agent that
participates in transactions involving sales of the shares against certain
liabilities, including


                                       22
<PAGE>
liabilities arising under the Securities Act.

         In addition, each selling security holder will be subject to applicable
provisions of the Exchange Act of 1934 and the associated rules and regulations
under the Exchange Act of 1934, including Regulation M, which provisions may
limit the timing of purchases and sales of shares of our common stock by the
selling security holders.

         We will make copies of this prospectus available to the selling
security holders and have informed them of the need for delivery of copies of
this prospectus to purchasers at or prior to the time of any sale of the shares.
We will file a supplement to this prospectus, if required, pursuant to Rule
424(b) under the Securities Act of 1933 upon being notified by a selling
security holder that any material arrangement has been entered into with a
broker-dealer for the sale of shares through a block trade, special offering,
exchange distribution or secondary distribution or a purchase by a broker or
dealer.

         There can be no assurance that the selling security holders will sell
all or any of the common stock.

         The selling security holders and us have agreed to customary
indemnification obligations with respect to the sale of common stock by use of
this prospectus.


                                       23
<PAGE>
                             REPORTS TO SHAREHOLDERS

         We distribute annual reports to our stockholders, including audited
financial statements, and will provide such other reports as management may deem
necessary or appropriate to keep stockholders informed of our company's
operations.

                                  LEGAL MATTERS

         The legality of the offering of the shares will be passed upon for us
by Goldstein & DiGioia, LLP, 369 Lexington Avenue, New York, New York l00l7.
Members of the firm, or companies owned by affiliates of the members, own in the
aggregate approximately 70,000 shares of the common stock of Authentidate
Holding Corp., which shares are not covered by this prospectus.

                                     EXPERTS

         The financial statements incorporated in this Prospectus by reference
to the Annual Report on Form 10-K, as amended, for the year ended June 30, 2001
have been so incorporated in reliance on the report of PricewaterhouseCoopers
LLP, independent accountants, given on the authority of said firm as experts in
auditing and accounting.

                             ADDITIONAL INFORMATION

         We have filed a Registration Statement under the Act with the
Securities and Exchange Commission, with respect to the securities offered by
this prospectus. This prospectus does not contain all of the information set
forth in the registration statement. For further information with respect to our
company and such securities, reference is made to the registration statement and
to the exhibits and schedules filed therewith. Each statement made in this
prospectus referring to a document filed as an exhibit to the registration
statement is qualified by reference to the exhibit for a complete statement of
its terms and conditions. The registration statement, including exhibits
thereto, may be inspected without charge to anyone at the office of the
Commission, and copies of all or any part thereof may be obtained from the
Commission's principal office in Washington, D.C. upon payment of the
Commission's charge for copying.


                                       24
<PAGE>
                           FORWARD LOOKING STATEMENTS

         Certain statements in this Prospectus constitute "forward-looking
statements" within the meaning of the Private Securities Litigation Reform Act
of 1995. We desire to avail ourselves of certain "safe harbor" provisions of the
1995 Reform Act and are therefore including this special note to enable us to do
so. Forward-looking statements included in this Prospectus or hereafter included
in other publicly available documents filed with the Securities and Exchange
Commission, reports to our stockholders and other publicly available statements
issued or released by us involve known and unknown risks, uncertainties, and
other factors which could cause our actual results, performance (financial or
operating) or achievements to differ from the future results, performance
(financial or operating) achievements expressed or implied by those forward
looking statements. These future results are based upon management's best
estimates of current conditions and the most recent results of our operations.
The statements appear in a number of places in this Prospectus and include
statements regarding our intent, belief or current expectations, and those of
our directors or officers with respect to: (i) future revenues,(ii) product
development, (iii) success in implementing the Authentidate business plan, (iv)
the document imaging system industry, and (v) other matters. Our actual results
could differ materially from those anticipated in the forward looking statements
as a result of certain factors, including those discussed throughout this
Prospectus. These risks include, but are not limited to, risks associated with
recent and accumulated losses, competition, conflicts of interest, limited
operating history, dependence upon one product line, and other risks detailed in
this Prospectus and our Securities and Exchange Commission filings, including
our Annual Report on Form 10-K, Quarterly Reports on Form 10-Q, as well as
recently filed Reports on Form 8-K, if any, each of which could adversely affect
our business and the accuracy of the forward looking statements contained
herein.


                                       25
<PAGE>
PART II

                   INFORMATION NOT REQUIRED IN THE PROSPECTUS

ITEM 3. INCORPORATION OF CERTAIN DOCUMENTS BY REFERENCE

         The following documents, heretofore filed by Authentidate Holding Corp.
with the Commission pursuant to the Exchange Act, are hereby incorporated by
reference, except as superseded or modified herein:

         1.       Our Annual Report on Form 10-K, as amended, for the fiscal
                  year ended June 30, 2001.

         2.       Our Quarterly Reports on Form 10-Q for the fiscal quarters
                  ended September 30, 2001, December 31, 2001 and March 31,
                  2002.

         3.       Our Reports on Form 8-K dated November 29, 2001, March 15,
                  2002, May 9, 2002, August 5, 2002 and August 6, 2002.

         4.       Our Proxy Statement for our Annual Meeting of Shareholders
                  held on January 24, 2002.

         5.       A description of our common stock contained in our
                  registration statement on Form 8-A filed April 17, 2000.

         All documents that we file subsequent to the date of this Prospectus
pursuant to Section 13(a), 13(c), 14 or 15(d) of the Exchange Act and prior to
the filing of a post-effective amendment which indicates that all Shares offered
hereby have been sold or which deregisters all Shares then remaining unsold,
shall be deemed to be incorporated by reference in this Registration Statement
and Prospectus and to be a part hereof from the date of filing of such
documents. Any statement contained in a document incorporated or deemed to be
incorporated by reference herein shall be deemed modified or superseded for
purposes of this Registration Statement and Prospectus to the extent that a
statement contained herein or in any other subsequently filed document which
also is or is deemed to be incorporated by reference herein modifies or
supersedes such statement. Any such statement so modified or superseded shall
not be deemed, except as so modified or superseded, to constitute a part of the
Registration Statement of which this Prospectus forms a part. We will provide
without charge to each person to whom a copy of this Prospectus is delivered,
upon the written or oral request of any such person, a copy of any document
described above (other than exhibits). Requests for such copies should be
directed to Authentidate Holding Corp., 2165 Technology Drive, Schenectady, New
York 12308, telephone (518) 346-7799, Attention: Chief Financial Officer.

ITEM 4.  DESCRIPTION OF SECURITIES.

         Not Applicable.

ITEM 5.  INTERESTS OF NAMED EXPERTS AND COUNSEL.

         Not Applicable.


                                       26
<PAGE>
ITEM 6.  INDEMNIFICATION OF DIRECTORS AND OFFICERS.

         The General Corporation Law of Delaware provides generally that a
corporation may indemnify any person who was or is a party to or is threatened
to be made a party to any threatened, pending or completed action, suit or
proceeding, whether civil, criminal, administrative, or investigative in nature,
by reason of the fact that he is or was a director, officer, employee or agent
of the corporation, or is or was serving at the request of the corporation as a
director, officer, employee or agent of another corporation, partnership, joint
venture, trust or other enterprise, against expenses (including attorneys' fees)
and, in a proceeding not by or in the right of the corporation, judgments, fines
and amounts paid in settlement, actually and reasonably incurred by him in
connection with such suit or proceeding, if he acted in good faith and in a
manner believed to be in or not opposed to the best interests of the
corporation, and, with respect to any criminal action or proceeding, had no
reason to believe his conduct was unlawful. Delaware law further provides that a
corporation will not indemnify any person against expenses incurred in
connection with an action by or in the right of the corporation if such person
shall have been adjudged to be liable for negligence or misconduct in the
performance of his duty to the corporation unless and only to the extent that
the court in which such action or suit was brought shall determine that, despite
the adjudication of liability but in view of all the circumstances of the case,
such person is fairly and reasonably entitled to indemnity for the expenses
which such court shall deem proper.

         Our By-Laws provide for indemnification of our officers and directors
to the greatest extent permitted by Delaware law for any and all fees, costs and
expenses incurred in connection with any action or proceeding, civil or
criminal, commenced or threatened, arising out of services by or on behalf of
us, providing such officer's or director's acts were not committed in bad faith.
The By-Laws also provide for advancing funds to pay for anticipated costs and
authorizes the Board to enter into an indemnification agreement with each
officer or director.

         In accordance with Delaware law, our Certificate of Incorporation
contains provisions eliminating the personal liability of directors, except for
(i) breaches of a director's fiduciary duty of loyalty to us or to our
stockholders, (ii) acts or omissions not in good faith or which involve
intentional misconduct or a knowing violation of the law, and (iii) any
transaction in which a director receives an improper personal benefit. These
provisions only pertain to breaches of duty by directors as such, and not in any
other corporate capacity, e.g., as an officer. As a result of the inclusion of
such provisions, neither Authentidate Holding Corp. nor our stockholders may be
able to recover monetary damages against directors for actions taken by them
which are ultimately found to have constituted negligence or gross negligence,
or which are ultimately found to have been in violation of their fiduciary
duties, although it may be possible to obtain injunctive or equitable relief
with respect to such actions. If equitable remedies are found not to be
available to stockholders in any particular case, stockholders may not have an
effective remedy against the challenged conduct.

         We have entered into Indemnification Agreements with each of our
directors and officers (the "Indemnitees") pursuant to which we have agreed to
provide for indemnification, to the fullest extent permitted by law and our
By-Laws, against any and all expenses, judgments, fines, penalties and amounts
paid in settlement arising out of any claim in connection with any event,
occurrence or circumstance related to such individual serving as a director or
officer of us. Such indemnification includes the advance of expenses to the
Indemnitees (including the payment of funds in trust therefor under certain
circumstances) and is subject to there not having been determined that the
Indemnitee would not be permitted to be indemnified under applicable law. The
rights of indemnification are in addition to any other rights which the
Indemnitees may have


                                       27
<PAGE>
under our Certificate of Incorporation, By-Laws, the Delaware General
Corporation Law or otherwise.

ITEM 7.  EXEMPTION FROM REGISTRATION CLAIMED.

         Not Applicable

ITEM 8.  EXHIBITS.

         The exhibits designated with (*) are filed herewith. All other exhibits
have been previously filed with the Commission and, pursuant to 17 C.F.R. Secs.
201.24 and 240.12b- 32, are incorporated by reference to the document referenced
in brackets following the description of such exhibits.

<TABLE>
<CAPTION>
EXHIBIT
NO.               DESCRIPTION
- ---               -----------
<S>               <C>
4.1               Form of Common Stock Certificate (Exhibit 4.1 to Registration Statement on
                  Form S-18, File No. 33-46246-NY)

5.*               Opinion of Goldstein & DiGioia, LLP re legality of shares offered.

23.1*             Consent of PricewaterhouseCoopers, LLP.

23.2*             Consent of Goldstein & DiGioia, LLP, contained in Exhibit 5.

99.1              2001 Non-Executive Director Stock Option Plan (filed as Exhibit 1 to Definitive
                  Proxy Statement dated December 18, 2001 as filed with the Securities and
                  Exchange Commission).
</TABLE>

ITEM 9.  UNDERTAKINGS

We hereby undertake:

A.       (1) To file, during any period in which offers or sales are being made,
a post-effective amendment to this registration statement:

                  (i) To include any prospectus required by Section 10(a)(3) of
the Securities Act of 1933;

                  (ii) To reflect in the prospectus any facts or events arising
after the effective date of the registration statement (or the most recent
post-effective amendment thereto) which, individually or in the aggregate,
represent a fundamental change in the information set forth in the Registration
Statement;

                  (iii) To include any material information with respect to the
plan of distribution not previously disclosed in the registration statement or
any material change to such information in the registration statement;

         (2) That, for the purpose of determining any liability under the
Securities Act of 1933,


                                       28
<PAGE>
each such post-effective amendment shall be deemed to be a new registration
statement relating to the securities offered therein, and the offering of such
securities at that time shall be deemed to be the initial bona fide offering
thereof.

         (3) To remove from registration by means of a post-effective amendment
any of the securities being registered which remain unsold at the termination of
the offering.

         (4) (i) For the purpose of determining any liability under the
Securities Act of 1933, the information omitted from the form of prospectus
filed as part of this Registration Statement in reliance upon Rule 430A and
contained in the form of prospectus filed by the Registrant pursuant to Rule
424(b)(1) or (4) or 497(h) under the Securities Act shall be deemed to be part
of the Registration Statement as of the time it was declared effective.

                  (ii) For the purpose of determining any liability under the
Securities Act of 1933, each post-effective amendment that contains a form of
prospectus shall be deemed to be a new registration statement relating to the
securities offered therein, and the offering of such securities at that time
shall be deemed to be the initial bona fide offering thereof.

         (5) For purposes of determining any liability under the Securities Act
of 1933, each filing of our annual report pursuant to Section 13(a) or Section
15(d) of the Securities Exchange Act of 1934 (and, where applicable, each filing
of an employee benefit plan's annual report pursuant to Section 15(d) of the
Securities Exchange Act of 1934) that is incorporated by reference in the
registration statement shall be deemed to be a new registration statement
relating to the securities offered therein, and the offering of such securities
at that time shall be deemed to be the initial bona fide offering thereof.

B. Insofar as indemnification for liabilities arising under the Securities Act
of 1933 may be permitted to directors, officers and controlling persons of the
Registrant pursuant to the foregoing provisions, or otherwise, the Registrant
has been advised that in the opinion of the Securities and Exchange Commission
such indemnification is against public policy as expressed in the Act and is,
therefore, unenforceable. In the event that a claim for indemnification against
such liabilities (other than the payment by the registrant of expenses incurred
or paid by a director, officer or controlling person of the registrant in the
successful defense of any action, suit or proceeding) is asserted by such
director, officer or controlling person in connection with the securities being
registered, the registrant will, unless in the opinion of its counsel the matter
has been settled by controlling precedent, submit to a court of appropriate
jurisdiction the question whether such indemnification by it is against public
policy as expressed in the Act and will be governed by the final adjudication of
such issue.


                                       29
<PAGE>
                                   SIGNATURES

         Pursuant to the requirements of the Securities Act of 1933, we certify
that we have reasonable grounds to believe that we meet all of the requirements
for filing on Form S-8 and have duly caused this Registration Statement to be
signed on our behalf by the undersigned, thereunto duly authorized, in the City
of Schenectady, New York, on August 6, 2002.

                             AUTHENTIDATE HOLDING CORP.



                             By:  /s/ JOHN T. BOTTI
                                  ----------------------------------------
                                  John T. Botti
                                  Chief Executive Officer, Chairman of the Board
                                   and President

                  KNOW ALL MEN BY THESE PRESENTS, that each person whose
signature appears below substitutes and appoints John Botti his true and lawful
attorney-in-fact and agents, with full power of substitution and resubstitution,
for him and in his name, place and stead, in any and all capacities, to sign any
and all amendments (including post-effective amendments) to this Registration
Statement, and to file the same, with all exhibits thereto, and other documents
in connection therewith, with the Securities and Exchange Commission, granting
unto said attorney-in-fact and agent full power and authority to do and perform
each and every act and thing requisite and necessary to be don in and about the
premises, as fully to all intents and purposes as he might or could do in
person, hereby ratifying and confirming all that said attorney-in-fact and agent
or his substitute, may lawfully do or cause to be done by virtue hereof.

                  Pursuant to the requirements of the Securities Exchange Act of
1933, this registration statement has been signed below by the following persons
on our behalf and in the capacities and on the dates indicated.

<TABLE>
<CAPTION>
NAME                                        TITLE                                              DATE
<S>                                         <C>                                                <C>
/s/John T. Botti                            Chairman of the Board, President                   August 6, 2002
- ----------------                            and Chief Executive Officer
John T. Botti

/s/ Robert Van Naarden                      Director and Chief Executive                       August 12, 2002
- ----------------------                      Officer, Authentidate, Inc.
Robert Van Naarden

/s/Steven A. Kreigsman                      Director                                           August 8, 2002
- ----------------------
Steven A. Kriegsman

/s/J. Edward Sheridan                       Director                                           August 6, 2002
- ---------------------
J. Edward Sheridan

/s/Charles C. Johnston                      Director                                           August 6, 2002
- ----------------------
Charles C. Johnston
</TABLE>


                                       30
<PAGE>



<TABLE>
<S>                                         <C>                                                <C>
/s/Dennis H. Bunt                           Chief Financial Officer and                        August 7, 2002
- -----------------                           Principal Accounting Officer
Dennis H. Bunt

/s/ Thomas Franceski                        Vice President, Technology                         August 6, 2002
- --------------------                        Products Group
Thomas Franceski
</TABLE>



                                       31
[{"type": "S-8", "sequence": "1", "filename": "y62909sv8.txt", "description": "AUTHENTIDATE HOLDING CORP.", "secsgml_size_bytes": 104280}]
{"company-data": {"conformed-name": "AUTHENTIDATE HOLDING CORP", "cik": "0000885074", "assigned-sic": "7373", "irs-number": "141673067", "state-of-incorporation": "DE", "fiscal-year-end": "0630"}, "filing-values": {"form-type": "S-8", "act": "33", "file-number": "333-97965", "film-number": "02727409"}, "business-address": {"street1": "BLDG 50 ROTTERDAM INDUSTRIAL PK", "city": "SCHENECTADY", "state": "NY", "zip": "12306", "phone": "5183569741"}, "mail-address": {"street1": "BLDG 50 ROTTERDAM INDUSTRIAL PARK", "city": "SCHENECTADY", "state": "NY", "zip": "12306"}, "former-company": {"former-conformed-name": "BITWISE DESIGNS INC", "date-changed": "19930328"}}
As filed with the Securities and Exchange Commission on August 12, 2002

                                                           File No. 333-________

                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549
                            -------------------------
                                    FORM S-8
                             REGISTRATION STATEMENT
                                      Under
                           THE SECURITIES ACT OF 1933
                            -------------------------

                           AUTHENTIDATE HOLDING CORP.
             (Exact name of Registrant as specified in its charter)

         Delaware                2165 Technology Drive        14-1673067
(State of Incorporation)         Schenectady, NY 12308      (I.R.S. Employer
                                    (518) 346-7799        Identification Number)

               (Address, including zip code, and telephone number,
        including area code, of registrant's principal executive offices)

                  2001 NON-EXECUTIVE DIRECTOR STOCK OPTION PLAN
                               (Full Name of Plan)
                                -----------------
                                  John T. Botti
                             Chief Executive Officer
                              2165 Technology Drive
                              Schenectady, NY 12308
                                 (518) 346-7799
          (Name and address, including zip code, and telephone number,
                   including area code, of agent for service)
                                -----------------
                                 With copies to:
                             Victor J. DiGioia, Esq.
                           Michael A. Goldstein, Esq.
                            GOLDSTEIN & DIGIOIA, LLP
                              369 Lexington Avenue
                            New York, New York 10017
                            Telephone (212) 599-3322
                            Facsimile (212) 557-0295
CALCULATION OF REGISTRATION FEE
===================================================================================================================================
                                                                                 Proposed            Proposed
                                                                                  Maximum             Maximum
                                                                                 Offering             Aggregate        Amount of
Title of Each Class of Securities Being              Amount to be                Price per            Offering         Registration
Registered                                           Registered                  Share(1)             Price(1)         Fee
- -----------------------------------------------------------------------------------------------------------------------------------
Common Stock, $.001 par
value......................                            500,000                   $3.55               $1,775,000          $163.30
- -----------------------------------------------------------------------------------------------------------------------------------
Total......................                            500,000                                       $1,775,000          $163.30

===================================================================================================================================
(1)      Estimated solely for the purpose of determining the registration fee,
         in accordance with Rule 457(h), based on the average of the high and
         low prices of a share of Common Stock as quoted on the Nasdaq National
         Market on August 8, 2002 ($3.55 per share).

         ---------------------------

         THE REGISTRANT HEREBY AMENDS THIS REGISTRATION STATEMENT ON SUCH DATE
OR DATES AS MAY BE NECESSARY TO DELAY ITS EFFECTIVE DATE UNTIL THE REGISTRANT
SHALL FILE A FURTHER AMENDMENT WHICH SPECIFICALLY STATES THAT THIS REGISTRATION
STATEMENT SHALL THEREAFTER BECOME EFFECTIVE IN ACCORDANCE WITH SECTION 8(a) OF
THE SECURITIES ACT OF 1933 OR UNTIL THE REGISTRATION STATEMENT SHALL BECOME
EFFECTIVE ON SUCH DATE AS THE COMMISSION ACTING PURSUANT TO SECTION 8(a) MAY
DETERMINE.

                                       ii
PART I

              INFORMATION REQUIRED IN THE SECTION 10(a) PROSPECTUS

ITEM 1.  PLAN INFORMATION

         This Registration Statement relates to 500,000 shares of Common Stock,
$.001 par value, of Authentidate Holding Corp., authorized for issuance in
connection with the grant of options to the company's non-executive directors
and other authorized persons under its 2001 Non-Executive Director Stock Option
Plan. At the Annual Meeting of Stockholders held on January 24, 2002, our
shareholders approved the adoption of the 2001 Non- Executive Director Stock
Option Plan. Under the 2001 Non-Executive Director Plan, each non-executive
director will automatically be granted an option to purchase 20,000 shares upon
joining the Board and an option to purchase 10,000 shares each September 1st
thereafter, pro rata, based on the time the director has served in such capacity
during the previous year. The exercise price for options granted under the 2001
Non-Executive Director Plan shall be 100% of the fair market value of the common
stock on the date of grant.

         Pursuant to Rule 428(b)(1) of the Securities Act of 1933, as amended,
the documents containing the information specified in Part I for Form S-8 will
be sent or given to participants in the Non-Executive Director Plan. In
accordance with the instructions to Part I of Form S-8, the Non-Executive
Director Plan and related documents are not being filed with the Securities and
Exchange Commission as part of the registration statement or as prospectuses or
prospectus supplements pursuant to Rule 424. The foregoing documents and the
documents incorporated by reference in this Registration Statement, taken
together, constitute a Prospectus that meets the requirements of Section 10(a)
of the Securities Act of 1933, as amended.

         There is also as part of Part I of this registration statement, a
re-offer prospectus, prepared in accordance with the requirements of Part I of
Form S-3, relating to and to be used in connection with any re-offer and resale
of an aggregate of 500,000 shares of our common stock by:

         -        persons who may be deemed to be our affiliates;

         -        any shares of common stock issued or to be issued to such
                  persons;

         -        and all persons holding restricted securities issued

pursuant to the exercise of the options granted under the 2001 Non-Executive
Director Stock Option Plan, all as permitted by General Instruction C of Form
S-8.

ITEM 2. REGISTRANT INFORMATION AND NON-EXECUTIVE DIRECTOR STOCK OPTION PLAN
ANNUAL INFORMATION

         Authentidate Holding Corp. will provide without charge to each person
to whom a copy of this Prospectus is delivered, upon the written or oral request
of any such person: (1) a copy of any document described in Item 3 of Part II of
this Registration Statement, which documents are incorporated by reference in
the Section 10(a) Prospectus (other than exhibits); and (2) the documents
required to be delivered to non-executive directors pursuant to Rule 428(b).
Requests for such copies should be directed to Dennis Bunt, Chief Financial
Officer, Authentidate Holding Corp., 2165 Technology Drive, Schenectady, New
York 12308, telephone (518) 346-7799.
RE-OFFER
P R O S P E C T U S              500,000 Shares

                           AUTHENTIDATE HOLDING CORP.

                                  Common Stock

         We are registering for resale an aggregate of 500,000 shares of common
stock, $.001 par value of Authentidate Holding Corp., which shares we will issue
upon the exercise of up to 500,000 shares of our common stock reserved for
issuance upon the exercise of options granted under our 2001 Non-Executive
Director Stock Option Plan.

         We will not receive any of the proceeds from the sale of the Shares by
the Selling Security Holders.

         Our common stock is traded in the over-the counter market and is quoted
on the Nasdaq National Market under the symbol "ADAT". On August 7, 2002, the
closing price for the common stock as reported on Nasdaq was $3.55.

          The shares may be sold from time to time by the selling security
holders, or by their transferees. No underwriting arrangements have been entered
into by the selling security holders. The distribution of the shares by the
selling security holders may be effected in one or more transactions that may
take place on the over the counter market, including ordinary brokers
transactions, privately negotiated transactions or through sales to one or more
dealers for resale of the shares as principals, at market prices prevailing at
the time of sale, at prices related to such prevailing market prices or at
negotiated prices. Usual and customary or specifically negotiated brokerage fees
or commissions may be paid by the selling security holders in connection with
such sales. The selling security holders and intermediaries through whom such
shares are sold may be deemed underwriters within the meaning of the Act, with
respect to the shares offered by them.

          PLEASE SEE "RISK FACTORS" BEGINNING ON PAGE 12 TO READ ABOUT
           CERTAIN FACTORS YOU SHOULD CONSIDER BEFORE BUYING SHARES OF
                                  COMMON STOCK.

          NEITHER THE SECURITIES AND EXCHANGE COMMISSION NOR ANY OTHER
          REGULATORY BODY HAS APPROVED OR DISAPPROVED THESE SECURITIES
         OR PASSED UPON THE ACCURACY OR ADEQUACY OF THIS PROSPECTUS. ANY
              REPRESENTATION TO THE CONTRARY IS A CRIMINAL OFFENSE.

                    Re-Offer Prospectus dated August 12, 2002

                                       iv
TABLE OF CONTENTS
PAGE
                                                                         ----
AVAILABLE INFORMATION..............................................        1

INCORPORATION OF CERTAIN DOCUMENTS BY REFERENCE....................        1

PROSPECTUS SUMMARY.................................................        3

THE COMPANY........................................................        3

THE OFFERING.......................................................       11

RISK FACTORS.......................................................       12

USE OF PROCEEDS ...................................................       20

SELLING SECURITY HOLDERS...........................................       21

PLAN OF DISTRIBUTION...............................................       22

REPORTS TO SHAREHOLDERS............................................       24

LEGAL MATTERS......................................................       24

EXPERTS  ..........................................................       24

ADDITIONAL INFORMATION.............................................       24

FORWARD LOOKING STATEMENTS.........................................       25
v
AVAILABLE INFORMATION

         We are subject to the informational reporting requirements of the
Securities Exchange Act of 1934, as amended, and, in accordance therewith, file
reports and other information with the Securities and Exchange Commission.
Reports, proxy and information statements and other information that we file
with the Commission pursuant to the informational requirements of the Exchange
Act may be inspected and copied at the public reference facilities maintained by
the Commission at 450 Fifth Street, N.W., Washington, D.C. 20549 and at the
following Regional Offices of the Commission: Northeast Regional Office,
Securities and Exchange Commission, 233 Broadway, New York, New York 10279; and
Chicago Regional Office, 500 West Madison Street, Room 1400, Chicago, Illinois
60661. Copies of such material may be obtained from the public reference section
of the Commission at 450 Fifth Street, N.W., Washington, D.C. 20549, at
prescribed rates. You may obtain information on the operation of the Public
Reference Room by calling the SEC at 1-800-SEC-0330. The SEC maintains an
Internet site, http://www.sec.gov, that contains reports, proxy and information
statements and other information that we file electronically with the SEC.

         We have filed with the Commission a registration statement on Form S-8
under the Securities Act with respect to the shares of common stock offered by
this re-offer prospectus. This re-offer prospectus does not contain all the
information set forth in or annexed as exhibits to the registration statement.
For further information with respect to our company and the shares of common
stock offered by this re-offer prospectus, reference is made to the registration
statement and to the financial statements, schedules and exhibits filed as part
thereof or incorporated by reference herein. Copies of the registration
statement, together with such financial statements, schedules and exhibits, may
be obtained from the public reference facilities of the Commission at the
addresses listed above, upon payment of the charges prescribed therefor by the
Commission. Statements contained in this re-offer prospectus as to the contents
of any contract or other document referred to are not necessarily complete and,
in each instance, reference is made to the copy of such contract or other
documents, each such statement being qualified in its entirety by such
reference. Copies of such contracts or other documents, tot he extent that they
are exhibits to this registration statement, may be obtained from the public
reference facilities of the Commission, upon the payment of the charges
prescribed therefor by the Commission.

                 INCORPORATION OF CERTAIN DOCUMENTS BY REFERENCE

         The following documents, heretofore filed by Authentidate Holding Corp.
with the Commission pursuant to the Exchange Act, are hereby incorporated by
reference, except as superseded or modified herein:

         1.       Our Annual Report on Form 10-K, as amended, for the fiscal
                  year ended June 30, 2001.

         2.       Our Quarterly Reports on Form 10-Q for the fiscal quarters
                  ended September 30, 2001, December 31, 2001 and March 31,
                  2002.

         3.       Our Reports on Form 8-K dated November 29, 2001, March 15,
                  2002, May 9, 2002, August 5, 2002 and August 6, 2002.

         4.       Our Proxy Statement for our Annual Meeting of Shareholders
                  held on January 24, 2002.

                                        1
5.       A description of our common stock contained in our
                  registration statement on Form 8-A filed April 17, 2000.

         Each document filed subsequent to the date of this prospectus pursuant
to Section 13(a), 13(c), 14 or 15(d) of the Exchange Act prior to the
termination of this offering shall be deemed to be incorporated by reference in
this prospectus and shall be part hereof from the date of filing of such
document.

         All documents filed by the registrant after the date of filing the
initial registration statement on Form S-8 of which this prospectus forms a part
and prior to the effectiveness of such registration statement pursuant to
Section 13(a), 13(c), 14 and 15(d) of the Securities Exchange Act of 1934 shall
be deemed to be incorporated by reference into this prospectus and to be part
hereof from the date of filing of such documents.

         We will provide without charge to each person to whom a copy of this
Prospectus is delivered, upon the written or oral request of any such person, a
copy of any document described above (other than exhibits). Requests for such
copies should be directed to Authentidate Holding Corp., 2165 Technology Drive,
Schenectady, New York 12308, telephone (518) 346-7799, Attention: Chief
Financial Officer.

                                        2
PROSPECTUS SUMMARY

         The following summary is intended to set forth certain pertinent facts
and highlights from material contained in our Annual Report on Form 10-K, as
amended, for the fiscal year ended June 30, 2001, and our Reports on Form 10-Q,
for the fiscal quarters ended September 30, 2001, December 31, 2001 and March
31, 2002, incorporated by reference into this prospectus.

                           AUTHENTIDATE HOLDING CORP.

OUR BUSINESS

         Authentidate Holding Corp. ("AHC"), its subsidiaries DJS Marketing
Group, Inc. ("DJS"), Authentidate, Inc., and Trac Medical Solutions, Inc. (f/k/a
WebCMN, Inc.), and through its joint ventures Authentidate International, AG,
and Authentidate Sports, Inc. (f/k/a Authentidate Sports Edition, Inc.)
(sometimes collectively referred to herein as the "Company"), are engaged in the
following businesses:

         -        the manufacture and distribution of document imaging systems;

         -        the development and sale of software-based authentication
                  products; and

         -        the sale and integration of computer systems and related
                  peripheral equipment, components, and accessories and network
                  and internet services.

         AHC was formerly known as Bitwise Designs, Inc. The name change was
approved by our shareholders at the March 23, 2001 Annual Meeting.

         In March 1996, we acquired DJS (d.b.a Computer Professionals), a
systems integrator and computer reseller in Albany, New York. DJS is an
authorized sales and support provider for Novell, Microsoft Solutions and Lotus
Notes.

         We established our Authentidate subsidiary during the fiscal year ended
June 30, 2000 to engage in the business of providing end users with a service
providing for the storage, confirmation and authentication of electronic data
and images. Subsequent to the formation of Authentidate, we established with a
German entity Authentidate International, A.G., a German corporation, to market
the Authentidate service in certain foreign countries. As discussed below,
Authentidate International is now a wholly-owned subsidiary of AHC. Authentidate
Sports, Inc., established during the fiscal year ended June 30, 2001, as a joint
venture with Internet Venture Capital, LLC, a partner experienced in the sports
memorabilia industry, is developing a service that applies the Authentidate
technology to the field of signature authentication as it relates to sports
memorabilia and entertainment collectibles. Our subsidiary, Trac Medical
Solutions, Inc., is in the process of developing a business model to apply the
Authentidate technology to the medical supply business relating to the
automation and processing of Certificates of Medical Necessity.

PRODUCTS AND SERVICES

         Document Imaging Systems

         In January 1996 we introduced our document imaging management system on
a national

                                        3
level under the tradename DocStar. Our DocStar product enables users to scan
paper documents onto an optical disk, hard drive or other storage medium from
which they can be retrieved in seconds. This system allows users to eliminate or
significantly reduce paper filing systems. We believe that a broad spectrum of
businesses and governmental agencies experience the problem of storage,
management and security of paper documents. The DocStar product line is intended
to provide a cost effective method of reducing the space necessary to store
documents while granting a user the ability to instantly retrieve documents.

         Authentication Software

         We have established the following subsidiaries and joint venture to
develop and sell software-based authentication services:

         -        Authentidate, Inc. - to provide a software-based service to
                  accept and store electronic files and date and time stamps
                  those files with a secure clock to prove content, date and
                  time authenticity;

         -        Authentidate International, A.G. - a wholly-owned subsidiary
                  to market the Authentidate service in certain foreign
                  countries;

         -        Authentidate Sports, Inc. - a joint venture established with
                  Internet Venture Capital, LLC, to develop an authentication
                  service based on our Authentidate technology for use in the
                  sports memorabilia and collectibles industries; and

         -        Trac Medical Solutions, Inc. - to develop a service based on
                  the Authentidate technology designed to facilitate the
                  processing of Certificates of Medical Necessity.

         Computer Products and Services

         Along with our subsidiary, DJS, we primarily market the following
different products and services:

         -        Computer Products and Integration Services;

         -        Network Services; and

         -        Internet/Intranet Development Services.

                              DOCSTAR PRODUCT LINE

         Our document imaging management system, marketed on a national level
under the tradename DocStar, enables users to scan paper documents onto an
optical disk, hard drive or other storage medium from which they can be
retrieved in seconds. We design and manufacture the DocStar product line, which
consists of a personal computer, proprietary software and may also include a
scanner. This system can be utilized as a "stand-alone" system or as part of a
network installation. We consider our DocStar division to be a software
business. While, we sell the hardware in order provide the customer with a
"turn-key" system, we believe that it is the software employed in the DocStar
system which differentiates us from our

                                        4
competitors.

         The operation of a DocStar unit is similar to that of a facsimile and
scanning machine. Documents are fed into an optical scanner that reads the
documents and stores the information on one of several alternative mass storage
devices. Documents can also be transmitted from or to the system via facsimile
machine or modem. Documents can be retrieved almost instantaneously for viewing,
printing or faxing thereby offering a significant time-saving tool to the modern
office.

         We market our DocStar products through a national dealer network of
approximately 100 dealers and anticipate the addition of several new dealers in
future fiscal quarters to expand into markets not currently served. We own one
dealership in the Albany, New York region, which also serves as a test market
for new applications and software.

                           AUTHENTIDATE BUSINESS LINES

         In 1999, we established a majority owned subsidiary named Authentidate,
Inc., to engage in a new business line of providing end users with a
software-based service which will:

         -        accept and store electronic images from networks and personal
                  computers throughout the world and from different operating
                  systems via the Internet;

         -        indelibly date and time stamp all electronic images received
                  using a secure clock;

         -        allow users to transmit only the "secure codes" to
                  Authentidate fileservers while maintaining the original within
                  the customers "firewall"; and

         -        allow users to prove authenticity of time, date and content of
                  stored electronic documents.

THE AUTHENTIDATE SERVICE

         The Authentidate product, marketed as the Enterprise Edition, was
released for sale in May, 2001. We contemplate that product integration
development work will be necessary for many applications or customers. We are in
the process of selling this product and recorded revenue of approximately
$25,000 during the fiscal year ended June 30, 2002. We initially retained a
third party consulting firm, Cap Gemini America, Inc., to program and develop
the Enterprise Edition. Currently, we have employed our own staff of software
developers to improve the products.

RELATED ENTITIES

         AHC formed a joint venture in March, 2000, known as Authentidate
International, AG, with a German company to develop the Authentidate software in
foreign languages and to market that product outside the Americas, Japan,
Australia, New Zealand and India. This company is currently in the market
development stage. On March 15, 2002, we consummated the acquisition of the
outstanding capital stock of Authentidate International not owned by us and
presently own all of the capital stock of this company.

                                        5
AHC established Authentidate Sports, Inc., a joint venture with
Internet Venture Capital, LLC, an investor experienced in the sports memorabilia
industry, during the fiscal year ended June 30, 2001. Authentidate Sports (f/k/a
Authentidate Sports Edition, Inc.) was created to market Authentidate services
to the sports memorabilia and collectibles industries. This company is currently
in the market development stage.

         AHC established Trac Medical Solutions, Inc. as WebCMN, Inc., in March,
2001 in order to develop a service to facilitate the processing of Certificates
of Medical Necessity. WebCMN changed its corporate name to Trac Medical
Solutions, Inc., in connection with its acquisition of various intellectual
property and other assets in October, 2001, including the trademark "Trac
Medical" and a patent application related to the business model it is
developing. Certificates of Medical Necessity must be filed by suppliers seeking
government reimbursement in connection with the placement of medical devices.
Trac Medical Solutions intends to develop a software- based service
incorporating our proprietary Authentidate technology designed to facilitate the
processing of these documents to reduce the time period for reimbursement
currently experienced by suppliers of medical devices. This service is currently
in the development stage.

                            DJS MARKETING GROUP, INC.

         DJS (d/b/a "Computer Professionals") is a network and systems
integrator of computer and peripheral products for a variety of customers,
including corporations, schools, government agencies, manufacturers and
distributors. DJS is a prominent systems integrator in the Albany, New York
region.

         DJS provides network integration, Internet/Intranet development,
accounting solutions, service, consultation, document management and video
conferences. DJS also services the products it sells by employing factory
trained computer technicians and network engineers.

PRODUCTS AND SERVICES

         Computer Products and Integration Services

          DJS purchases personal computers and peripheral computer products from
many different suppliers. Peripheral computer products are products that operate
in conjunction with computers, including but not limited to, printers, monitors,
scanners, modems and software. DJS configures various computer hardware and
peripheral products such as software together, to satisfy a customer's
individual needs.

         Network Integration Services

         DJS' network integration group designs, implements, installs, manages
and supports enterprise networks with products from Novell, Microsoft, UNIX,
Tricord, Synoptics, Compaq, Cisco and others. Applications that the network
system provides include E-mail, accounting systems, word processing,
communication and any other applications that require the sharing of
information. DJS designs customized solutions for its clients with precise
objectives and its engineers analyze hardware, software, and cabling to ensure
effective and affordable solutions.

                                        6
Internet/Intranet Development

         DJS offers services related to the Internet, including Internet
connectivity, web page development, and hardware installation. Additionally, DJS
assists its clients through the buying and implementation process with
Internet/Intranet training and ongoing support.

         Service and Consultation

         DJS's service department is authorized to repair and maintain all major
brand products sold by DJS, including warranty and post-warranty equipment. DJS
generally guarantees a four (4) hour response time for all service calls, with
an average resolution time of next day.

         DJS's engineers also provide complete system configuration services,
which includes installation of all hardware, including memory, disk drives,
network or communication adapters, as well as any associated software or driver.
All units are thoroughly tested after configuration and all malfunctioning units
are eliminated.

         Document Management

         DJS also offers document imaging services which it believes is an
efficient and financially attainable alternative to conventional, costly paper
trails. Management believes digital documents can be stored, searched, retrieved
and edited in a fraction of the time with complete access to the network and
quality control features. Among other product lines, DJS offers customers our
DocStar line.

         Sales and Marketing

         DJS markets its products and services throughout New York State, parts
of Vermont and Massachusetts. DJS intends to expand its national and
international sales and marketing departments. Clients include corporations,
small office/home office owners, schools, government agencies, manufacturers and
distributors.

RECENT EVENTS

         Private Placement

         As of August 5, 2002, we have completed sales on an aggregate of
$2,000,035 in a private offering of our securities. The securities offered have
a purchase price of $3.03 per unit. We are offering a maximum of 1,584,158 units
in the private placement, each unit comprised of one share of common stock and
one warrant to purchase .20 shares of Common Stock. To date, we have sold an
aggregate of approximately 660,077 units.

         We have agreed to file a registration statement with the Securities and
Exchange Commission to register for resale the shares of common stock contained
in the units, including the shares underlying the warrants. In the event that we
do not timely file the registration statement, or it is not timely declared
effective, the investors will be entitled to liquidated damages equal to 2% of
the purchase price for each month that the relevant event is delayed.

         The proceeds of the financing will be used to increase the business
development, marketing and sales efforts for our services, along with our
general working capital needs. There can be no assurance that we will be able to
complete the maximum amount of the offering.

                                        7
The offering is intended to comply with Section 4 (2) of the Securities
Act of 1933 and/or Regulation D. Neither the units, shares or warrants have been
registered for offer or sale under the Securities Act; such securities are being
issued on the basis of the statutory exemption provided by Section 4(2) of the
Securities Act and/or Regulation D promulgated thereunder relating to
transactions by an issuer not involving any public offering. The transaction has
not been reviewed by, passed on or submitted to any Federal or state agency or
self-regulatory organization where an exemption is being relied upon. The
securities may not be sold, assigned or transferred unless (i) the sale,
assignment or transfer of such securities is registered under the Securities
Act, or (ii) the securities are sold, assigned or transferred in accordance with
all the requirements and limitations of Rule 144 under the Securities Act.

         U.S. Postal Service Contract

         On August 6, 2002, we announced that we entered into a strategic
alliance agreement with the United States Postal Service to be the provider of
the USPS Electronic Postmark(R) (EPM) service. Under the terms of the
non-exclusive agreement, our subsidiary, AuthentiDate, Inc., will provide the
management, technology and support for the United States Postal Service's EPM
system.

         The USPS Electronic Postmark(R) provides evidence that the content of a
document or file existed at a specific date and time, and the EPM is intended to
protect the integrity of the document or file by ensuring that it cannot be
altered without detection. The EPM uses patent pending technology offering
highly sophisticated encryption ensuring document authenticity and is intended
to be added to any application regardless of the computing platform or operating
system.

         The agreement, entered into on July 31, 2002, provides that
Authentidate and USPS will agree within thirty days of the effective date of the
Agreement for a plan for launching the EPM system. The initial term of the
agreement commences on the effective date and expires five years thereafter,
unless terminated as provided therein. Upon mutual agreement of the parties, the
agreement may be extended for three additional three-year terms, unless sooner
terminated. The aggregate term of the agreement shall in no event exceed a total
of fourteen years.

         The agreement may be terminated as follows:

                  -        By the mutual agreement of the parties;

                  -        By either party if one party materially breaches the
                           Agreement and such breach continues for a period of
                           thirty days after the date the non- breaching party
                           provides written notice of the breach.

                  -        By USPS, without penalty, at any time upon thirty
                           days written notice if regulatory, legislative or
                           judicial action or inaction occurs which
                           substantially impairs USPS's ability to perform its
                           obligations under this Agreement;

                  -        Commencing six months after the launch of the EPM
                           System, USPS may terminate the Agreement upon one
                           hundred eighty days written notice, for any reason;

                  -        We may, upon three hundred sixty days written notice,
                           terminate the

                                        8
Agreement for any reason; and

                  -        USPS may terminate this Agreement by giving thirty
                           days' written notice to us in the event that there is
                           a change in control in Authentidate.

         The agreement provides for revenue sharing between the parties based
on gross revenues.

         Pursuant to the terms of the Agreement, we will develop, integrate,
operate, host and maintain all elements of the EPM system. More specifically, we
will provide the staff and resources as necessary to support the EPM
development, operation and promotion efforts; enable EPM to interoperate with
products or systems used by customers; implement billing and accounting systems
to ensure prompt and efficient aggregation of gross revenues and to support
prompt payment of gross revenues; provide customer support; and implement the
sale and marketing of the EPM system.

         USPS shall support the EPM system as follows:

                  -        USPS will pay a total of $250,000 to Authentidate
                           provided that neither Authentidate Holding Corp. nor
                           Authentidate are in default under this Agreement;

                  -        provide necessary access to technical personnel and
                           information to assist in the development efforts for
                           program management, on-site security inspection, and
                           USPS certification and accreditation; and

                  -        promote the EPM system on USPS.com and provide
                           hyperlinks in accordance with standard USPS practice,
                           use its best efforts to identify potential corporate
                           and government customers, participate in strategic
                           sales efforts to acquire customers, issue public
                           announcements and press releases, send appropriate
                           USPS representatives for events, press tours,
                           interviews, and speaking engagements, provide
                           introductions to USPS contract public relations and
                           advertising agency firms and acknowledge
                           Authentidate's role in providing the EPM System for
                           any and all promotional and marketing purposes.

         Zylab International Transaction

         On January 9, 2002, we announced that we have entered into a letter of
intent to acquire the assets of Zylab International, Inc., a privately owned
company based in Germantown, Maryland for shares of AHC common stock. The letter
of intent contemplated that the purchase price will range between a minimum of
725,000 and a maximum of 1,000,000 shares of AHC common stock. The precise
number of shares to be issued as the purchase price was to be determined prior
to closing. The parties are negotiating potential alternative transactions which
may result in termination of the letter of intent. Pursuant to the letter of
intent, we loaned to Zylab an aggregate principle amount of $500,000

                                        9
, which loan is collateralized by all of the assets of Zylab,
including its intellectual property. The acquisition is subject to various terms
and conditions, including the completion of the due diligence investigation, the
negotiation of a definitive agreement and the approval of the respective boards
and Zylab's shareholders. Accordingly, there can be no assurance that the
transaction will be consummated. As of the date of this prospectus, the
transaction has not been consummated and we are negotiating with Zylab the terms
of pursuant to which they will repay our loan.

OUR OFFICES

         We were initially organized in August 1985 and reincorporated under the
laws of the state of Delaware in May 1992. Our executive offices are located at
2165 Technology Drive, Schenectady, New York 12308, our telephone number is
(518) 346-7799, and our Internet address is www.authentidatehc.com.

                                       10
THE OFFERING
Common Stock Offered by the
Selling Security Holders.........................    500,000

Common Stock Outstanding
  Prior to Offering (1) ...........................  19,969,480

Common Stock Outstanding
  After the Offering (2) .........................   20,469,480

Use of Proceeds...................................   Authentidate Holding Corp. will not receive any
                                                     proceeds from the sales of the Selling Shareholders.
                                                     We anticipate that proceeds received from the
                                                     exercise of any options will be used for working
                                                     capital and general corporate purposes. Please see
                                                     "Use of Proceeds."

Nasdaq National Market Symbol
(Common Stock):                                      "ADAT"
- --------------------

(1) Based on the number of shares actually outstanding as of August 6, 2002.

Unless otherwise specifically stated, information throughout this prospectus
excludes as of August 6, 2002:

- - 3,000,000 shares of Common Stock reserved for issuance under our 1992 Employee
Stock Option Plan, of which 1,339,742 shares have been reserved for currently
outstanding options;

- - 5,000,000 shares of Common Stock reserved for issuance under our 2000 Employee
Stock Option Plan, of which 2,807,357 shares have been reserved for currently
outstanding options;

- - 160,000 shares of Common Stock reserved for currently outstanding options
under our 1992 Director Plan;

- - 2,817,833 shares of Common Stock reserved for issuance upon the exercise of
currently outstanding warrants;

- - 373,333 shares of Common Stock reserved for issuance upon the conversion of
our Series B Preferred Stock; and

- - 825,593 shares of Common Stock reserved for issuance upon the conversion of
our Series C Preferred Stock.

(2) This assumes the exercise and conversion of all of securities for which
underlying shares are being registered.

                                       11
RISK FACTORS

         An investment in the securities offered hereby involves a high degree
of risk. The following factors, in addition to those discussed elsewhere, should
be considered carefully in evaluating us and our business. An investment in the
securities is suitable only for those investors who can bear the risk of loss of
their entire investment.

IF WE CONTINUE TO FACE UNCERTAINTIES IN MARKETING THE DOCSTAR SYSTEM AND
AUTHENTIDATE PRODUCT, WE MAY CONTINUE TO LOSE MONEY.

         We incurred losses of $9,340,103, $5,274,043 and $3,166,488 for the
fiscal years ended June 30, 2001, 2000 and 1999, respectively, and losses of
$2,533,384, $2,222,955 and $2,608,970 for the quarters ended March 31, 2002,
December 31, 2001 and September 30, 2001, respectively. We have incurred
significant costs developing our Authentidate services and will continue to
incur these costs in the future as we attempt to increase market awareness and
sales. We have also incurred significant costs to date in establishing and
maintaining the distribution channels for our DocStar products and will continue
to incur such costs in the future. In the event we determine to expand our
distribution channels, these costs would be expected to increase. Our prospects
should be considered in light of the difficulties frequently encountered in
connection with the establishment of a new business line and the competitive
environment in which we operate. There can be no assurance that we will be able
to achieve profitable operations in future operating periods.

WE HAVE LIMITED WORKING CAPITAL AND MAY NEED ADDITIONAL FUNDS TO FINANCE FUTURE
OPERATIONS.

         Our capital requirements have been and will continue to be significant.
We have been substantially dependent upon public offerings and private
placements of our securities and on short-term and long-term loans from lending
institutions to fund such requirements. We are expending significant amounts of
capital to promote and market the Authentidate product line, including the
offerings of our Trac Medical Solutions subsidiary and our Authentidate Sports
venture, and continue to promote our DocStar products. Due to these
expenditures, we have incurred significant losses to date. During the nine
months ended March 31, 2002 and for the fiscal year ended June 30, 2001, we used
$4,823,052 and $1,391,651 in cash from operating activities, respectively. We
have capitalized the software development costs relating to our new Authentidate
product and our ability to recover such costs is highly dependent on the future
success of the marketing and sales of this product. If the revenue generated
from our Authentidate product is less than anticipated, the carrying value of
the software development costs may be impaired and require an impairment charge
in the future.

         As described on page 8 of this prospectus, we closed on an aggregate of
$2,000,035 of our equity securities in a private placement pursuant to Section
4(2) of the Securities Act of 1933, as amended, and Regulation D, promulgated
thereunder. While we are offering a maximum of $4,800,000 of our securities in
the private placement, there can be no guarantee that we will close on any
additional funds in this offering. We expect the net proceeds currently received
from this offering to satisfy our cash needs for an additional six months. If we
close on the maximum offering, we expect the net proceeds to satisfy our cash
needs for twelve months. In the future, we may need additional funds from loans
and/or the sale of equity securities to fully implement our business plans. No
assurance can be given that such funds will be available or, if

                                       12
available, will be on commercially reasonable terms satisfactory to us. In the
event such funds are not available, we will be forced to reduce our current and
proposed operations.

WE HAVE INCURRED SIGNIFICANT ADDITIONAL COSTS CONCERNING OUR INTERNATIONAL
OPERATIONS AND MAY INCUR ADDITIONAL COSTS IN THE FUTURE.

         On March 15, 2002, we consummated a transaction to acquire all of the
outstanding capital shares of Authentidate International, AG held by our
co-venturers. Pursuant to the Stock Purchase Agreement, we repurchased all of
the outstanding shares of Authentidate International in exchange for an
aggregate of 1,425,875 shares of our common stock and warrants to purchase
100,000 shares of our common stock. In connection with this transaction, certain
of the sellers also surrendered to us for cancellation an aggregate of 250,000
warrants to purchase shares of our common stock which were previously issued to
them. In connection with this transaction, we made a $500,000 loan to
Authentidate International as of December 24, 2001. Our ability to collect on
the loan will be dependent upon the profitability of Authentidate International.
There can be no assurances, however, that Authentidate International will
achieve profitability. We may incur additional expenses in subsequent to the
consummation of the proposed transaction in operating Authentidate International
as a wholly-owned subsidiary of our company. Further, we entered into an
employment agreement with Mr. Jan C.E. Wendenburg, pursuant to which Mr.
Wendenburg will serve as the Chief Executive Officer of Authentidate
International, AG, for a three year term. In consideration of his services, Mr.
Wendenburg will receive an initial base salary of US$200,000 and options to
purchase 184,000 shares of our common stock. We will also issue additional stock
options to other employees of Authentidate International, AG.

WE MAY ACQUIRE ADDITIONAL COMPANIES WHICH MAY RESULT IN ADVERSE EFFECTS ON OUR
EARNINGS AND WHICH MAY ADVERSELY AFFECT OUR MANAGEMENT AND OPERATING SYSTEMS.

         As described above, we have consummated the transaction to acquire
Authentidate International, AG and have been negotiating the terms of an
additional acquisition, as described on page 9 of this prospectus. Any
acquisition that we may consummate may have an adverse effect on our liquidity
and earnings and may be dilutive to our earnings. Further, in the event that we
consummate an acquisition or obtain additional capital through the sale of debt
or equity to finance an acquisition, our shareholders may experience dilution in
their shareholders' equity. Additionally, by growing through acquiring other
companies, significant demands are being made on our management, operations and
resources, including working capital. If we are not able to effectively manage
our growth, our business and operations will be materially harmed. To manage
growth effectively, we will be required to continue to improve our operational,
financial and managerial systems, procedures and controls, hire and train new
employees while managing our current operations and employees.

THE GRANT WE RECEIVED IN CONNECTION WITH THE CONSTRUCTION OF OUR HEADQUARTERS
REQUIRES US TO ATTAIN CERTAIN THRESHOLDS, THE ATTAINMENT OF WHICH MAY
SIGNIFICANTLY INCREASE OUR OPERATING COSTS.

         In June 1999, we completed construction of a new office and production
facility in Schenectady, New York for approximately $2,300,000, which was
financed with a $1,000,000 grant from the Empire State Development Corporation
(an agency of New York state) and a mortgage loan from a local financial
institution. The grant stipulates that we are obligated to achieve certain
annual employment levels between January 2002 and January 2006. While we

                                       13
have not currently achieved the agreed upon employment levels, we expect to
achieve such levels by 2006. In order to achieve the employment levels required
by the grant, we would incur substantial additional operating costs in
connection with the salaries and benefits to be received by the additional
employees. In the event we do not achieve the stipulated employment levels, some
or all of the grant will have to be repaid. Accordingly, the grant has been
classified as a long term liability on our balance sheet. In the event some or
all of the grant will be required to be repaid, we will either seek refinancing
from a financial institution, sell the building or pay the amounts due out of
our cash reserves.

OUR PRODUCTS MAY NOT BE ACCEPTED BY OUR CONSUMERS WHICH WOULD SERIOUSLY HARM OUR
BUSINESS.

         Although we introduced our DocStar imaging system products on a
national level in January 1996, demand and market acceptance for the DocStar
imaging system remains subject to a high level of uncertainty. Achieving
widespread acceptance of this product line will continue to require substantial
marketing efforts and the expenditure of significant funds to create brand
recognition and customer demand for such products. There can be no assurance
that adequate marketing arrangements will be made for such products. The
Authentidate product line is a new product line and there can be no assurance
that these products will ever achieve widespread market acceptance or increased
sales or that the sale of such products will be profitable.

IF WE CANNOT CONTINUOUSLY ENHANCE OUR PRODUCTS IN RESPONSE TO RAPID CHANGES IN
THE MARKET, OUR BUSINESS WILL BE HARMED.

         The computer industry and software-based services industry are
characterized by extensive research and development efforts which result in the
frequent introduction of new products which render existing products obsolete.
Our ability to compete successfully in the future will depend in large part on
our ability to maintain a technically competent research and development staff
and our ability to adapt to technological changes in the industry and enhance
and improve existing products and successfully develop and market new products
that meet the changing needs of our customers. Although we are dedicated to
continued research and development of our products with a view towards offering
products with the most advanced capabilities, there can be no assurance that we
will be able to continue to develop new products on a regular basis which will
be competitive with products offered by other manufacturers. At the present
time, we do not have a targeted level of expenditures for research and
development. We will evaluate all opportunities but believe the majority of our
research and development will be devoted to enhancements of our existing
products.

         Technological improvements in new products that we and our competitors
offer, which, among other things, results in the rapid decline of the value of
inventories, as well as the general decline in the economy and other factors,
have resulted in recent declines in retail prices for computer products. As
competitive pressures have increased, many companies have ceased operation and
liquidated inventories, further increasing downward pricing pressure. Such
declines have, in the past, and may in the future, reduce our profit margins.

WE DO NOT HAVE PATENTS ON ALL THE TECHNOLOGY WE USE WHICH COULD HARM OUR
COMPETITIVE POSITION.

                                       14
We do not currently hold any patents and the technology embodied in
some of our current products cannot be patented. We have four patents pending
for the innovative technology underlying the Authentidate business plan that can
verify the authenticity of digital images by employing a secure clock to stamp
the date and time on each image captured and have one patent pending concerning
the associated business process. We recently acquired the rights to an
additional patent application related to our Trac Medical Solutions, Inc.,
business model. We have also registered as trademarks the logos "DocStar" and
"Authentidate" and acquired the registered trademark "Trac Medical". We rely on
confidentiality agreements with our key employees to the extent we deem it to be
necessary. We further intend to file a patent application for any new products
we may develop, to the extent any technology included in such products is
patentable, if any. There can be no assurance that any patents in fact, will be
issued or that such patents will be effective to protect our products from
duplication by other manufacturers. In addition, there can be no assurance that
any patents that may be issued will be effective to protect our products from
duplication by other developers.

         Other companies operating within our business segment may independently
develop substantially equivalent proprietary information or otherwise obtain
access to our know-how. In addition, there can be no assurance that we will be
able to afford the expense of any litigation which may be necessary to enforce
our rights under any patent. Although we believe that the products we sell do
not and will not infringe upon the patents or violate the proprietary rights of
others, it is possible that such infringement or violation has or may occur. In
the event that products we sell are deemed to infringe upon the patents or
proprietary rights of others, we could be required to modify our products or
obtain a license for the manufacture and/or sale of such products. There can be
no assurance that, in such an event, we would be able to do so in a timely
manner, upon acceptable terms and conditions, or at all, and the failure to do
any of the foregoing could have a material adverse effect upon our business.
Moreover, there can be no assurance that we will have the financial or other
resources necessary to enforce or defend a patent infringement or proprietary
rights violation action. In addition, if our products or proposed products are
deemed to infringe upon the patents or proprietary rights of others, we could,
under certain circumstances, become liable for damages, which could also have a
material adverse effect on our business.

WE DEPEND ON OTHERS FOR COMPONENTS OF OUR PRODUCTS, WHICH MAY RESULT IN DELAYS
AND QUALITY-CONTROL ISSUES.

         We do not own or lease any manufacturing facilities and do not
manufacture any of the component parts for our products. Rather, we purchase all
of these components from unaffiliated suppliers. All of our products are
assembled at our facilities. We believe that at the present time we have
sufficient sources of supply of component parts, and that in the event any
existing supplier ceases to furnish component parts to us, alternative sources
are available. However, there can be no assurance that the future production
capacity of our current suppliers and manufacturers will be sufficient to
satisfy our requirements or that alternate suppliers and manufacturers will be
available on commercially reasonable terms, or at all. Further, there can be no
assurance that the availability of such supplies will continue in the future.

IF OUR PRODUCTS ARE NOT COMPETITIVE, OUR BUSINESS WILL SUFFER.

         Authentidate Holding Corp. and its subsidiaries are engaged in the
highly competitive

                                       15
businesses of assembling and distributing document imaging systems,
software-based authentication products, computer hardware and software as well
as technical support services for such businesses. The document imaging business
is competitive and we compete with major manufacturers. Many of these companies
have substantially more experience, greater sales, as well as greater financial
and distribution resources than do we. The most significant aspects of
competition are the quality of products, including advanced capabilities, and
price. There can be no assurance that we can effectively continue to compete in
the future.

         Our Authentidate business is a new business line and the level of
competition is unknown at this point in time. There can be no assurances,
however, that Authentidate products will achieve market acceptance.

         Our DJS subsidiary is engaged in the highly competitive business of
systems integration, computer services and computer reselling. DJS competes with
many small and local companies which provide similar technical services to those
offered by DJS. Additionally, DJS must compete with other computer resellers,
many of whom have greater financial and technical resources. There can be no
assurance that DJS will be able to compete successfully with these competitors.

IF WE LOSE OUR PRESIDENT, OUR BUSINESS WILL BE HARMED.

         Our success is largely dependent upon the services of our Chairman of
the Board and President, John T. Botti. The loss of his services would have a
material adverse affect on our business and prospects. We have entered into a
three-year employment agreement with Mr. Botti expiring in January, 2003. We
have obtained, for our benefit, "key man" life insurance in the amount of
$1,000,000 on Mr. Botti's life.

SINCE WE HAVE NOT PAID DIVIDENDS ON OUR COMMON STOCK, YOU MAY NOT RECEIVE INCOME
FROM THIS INVESTMENT.

         We have not paid any dividends on our Common Stock since our inception
and do not contemplate or anticipate paying any dividends on our Common Stock in
the foreseeable future. Earnings, if any, will be used to finance the
development and expansion of our business.

IF OUR COMMON STOCK IS DELISTED FROM NASDAQ, LIQUIDITY IN OUR COMMON STOCK MAY
BE AFFECTED.

         Our Common Stock is listed for trading on the Nasdaq National Market.
In order to continue to be listed on Nasdaq, however, we must meet certain
criteria, including one of the following:

         -        maintaining $4,000,000 in net tangible assets, a minimum bid
                  price of $1.00 per share and a market value of its public
                  float of $5,000,000; or

         -        having a market capitalization of at least $50,000,000, a
                  minimum bid price of $5.00 per share and a market value of its
                  public float of $15,000,000.

         On August 5, 2002, our closing bid price was $4.06. The dilution to our
shareholders which could be caused by the widespread conversion of the Series B
and Series C Preferred

                                       16
Stock could cause the per share value of our common stock to drop below the
minimum bid of $1.00 required for continued listing. As of March 31, 2002, we
had net tangible assets of approximately $7,618,437 and as of March 29, 2002 the
market value of our public float was approximately $82,524,998.

         In the future, if we should fail to meet Nasdaq maintenance criteria,
our Common Stock may be delisted from Nasdaq, and trading, if any, in our
securities would thereafter be conducted in the non-Nasdaq over-the-counter
market. As a result of such delisting, an investor could find it more difficult
to dispose of, or to obtain accurate quotations as to the market value of, our
securities.

         Although we anticipate that our Common Stock will continue to be listed
for trading on Nasdaq, if the Common Stock were to become delisted from trading
on Nasdaq and the trading price of the Common Stock was below $5.00 per share on
the date the Common Stock was delisted, trading in such securities would also be
subject to the requirements of certain rules promulgated under the Exchange Act,
which require additional disclosure by broker-dealers in connection with any
trades involving a stock defined as a penny stock (generally, any non-Nasdaq
equity security that has a market price of less than $5.00 per share, subject to
certain exceptions). Such rules require the delivery, prior to any penny stock
transaction, of a disclosure schedule explaining the penny stock market and the
risks associated therewith, and impose various sales practice requirements on
broker-dealers who sell penny stocks to persons other than established customers
and accredited investors (generally institutions). For these types of
transactions, the broker-dealer must make a special suitability determination
for the purchaser and have received the purchaser's written consent to the
transaction prior to sale. The additional burdens imposed upon broker-dealers by
such requirements may discourage broker-dealers from effecting transactions in
our securities, which could severely limit the market price and liquidity of
such securities and the ability of purchasers to sell their securities in the
secondary market.

OUR SERIES B PREFERRED STOCK FINANCING MAY RESULT IN DILUTION TO OUR COMMON
SHAREHOLDERS.

         Dilution of the per share value of our common shares could result from
the conversion of most or all of the Series B Preferred Stock we sold in a
private placement in October 1999. Holders of our Series B Preferred Stock may
convert these shares into shares of our common stock at a conversion price of
$1.875 beginning one year after the issuance of the Series B Preferred Stock.
However, after three years from the closing, the conversion price is subject to
a floating rate equal to the lower of $1.875 or the average of the closing bid
and asked prices of our common stock for the immediately preceding ten
consecutive trading days ending one day prior to the notice of conversion;
provided, however, that the conversion price may not be lower than $0.875. As of
August 5, 2002, there are 28,000 shares of Series B Preferred Stock outstanding.

         The following chart presents the maximum number of common shares
issuable on conversion of the currently outstanding shares of Series B Preferred
Stock based on different conversion rates. While we expect to issue a maximum of
an additional 373,333 shares of common stock upon conversion of the Series B
Preferred Stock until October 5, 2002, we could issue a significantly greater
number of common shares upon conversion of the Series B Preferred Stock after
October 5, 2002, when the floating conversion rate is triggered.

                                       17
==============================================================================================
                                                                  Percentage of Total Shares
Conversion           Conversion      Maximum Number of Shares         of Common Stock
Period                  Rate         of Common Stock Issuable           Outstanding
==============================================================================================
10/6/2000 -            $1.875                373,333                       1.9%
10/5/2002
- ----------------------------------------------------------------------------------------------
10/6/2002 -            $1.875                373,333                       1.9%
- ----------------------------------------------------------------------------------------------
10/6/2002 -            $ 1.50                466,667                       2.4%
- ----------------------------------------------------------------------------------------------
10/6/2002 -            $ 1.00                700,000                       3.5%
- ----------------------------------------------------------------------------------------------
10/6/2002 -            $0.875                800,000                       4.0%
==============================================================================================
Regardless of the date of exercise, dilution could occur from the
widespread conversion of the Series B Preferred Stock. The following scenarios
could result in dilution to our common shareholders:

         -        In either period, the conversion price could be lower than the
                  actual trading price on the day of conversion. This could
                  result in the holder immediately selling all of its converted
                  common shares, which would have a dilutive effect on the value
                  of the outstanding common shares.

         -        After three years, if the average trading price falls below
                  $1.875, the lower the average trading price, the greater the
                  number of common shares that a holder of our Series B
                  Preferred Stock will receive upon conversion; provided,
                  however, that the conversion price may not be lower than
                  $0.875. This might further encourage the holders of the Series
                  B Preferred Stock to covert their shares into common shares.
                  The increased number of common shares would further depress
                  the average trading price of our common stock.

         -        The significant downward pressure on the trading price of our
                  common stock as Series B Preferred Stock holders converted
                  these securities and sell the common shares received on
                  conversion could encourage short sales by the holders of
                  Series B Preferred Stock or other shareholders. This would
                  place further downward pressure on the trading price of our
                  common stock. Even the mere perception of eventual sales of
                  common shares issued on the conversion of the Series B
                  Preferred Stock could lead to a decline in the trading price
                  of our common stock.

OUR SERIES C PREFERRED STOCK FINANCINGS MAY RESULT IN DILUTION TO OUR COMMON
SHAREHOLDERS.

         Dilution of the per share value of our common shares could result from
the conversion of most or all of the Series C Preferred Stock we sold in two
transactions pursuant to Regulation S to non-U.S. entities in May, 2001. Holders
of our Series C Preferred Stock may convert these shares into shares of our
common stock at a fixed conversion price of $4.845 beginning at the earlier of
one year after the issuance of the Series C Preferred Stock or upon the
effectiveness of a registration statement covering such shares. In addition, the
purchasers in these transactions received warrants to purchase such number of
shares of our common

                                       18
stock as equals 10% of the number of shares issuable upon conversion of the
Series C Preferred Stock, rounded up to the nearest 1,000 shares. The warrants
may not be exercised until the earlier of one year from the date of issuance or
upon the effectiveness of a registration statement covering the Common Stock
underlying the warrants. We initially issued 5,500 shares of Series C Preferred
Stock which are convertible into an aggregate of 1,135,191 shares of Common
Stock and 114,000 warrants. As of the date of this prospectus, there are
outstanding 4,000 shares of Series C Preferred Stock which are convertible into
an aggregate of 825,593 shares of Common Stock and 114,000 warrants.

WE HAVE SOLD RESTRICTED SHARES WHICH MAY DEPRESS OUR STOCK PRICE WHEN IT IS
SELLABLE UNDER RULE 144.

         As of August 5, 2002, there were 2,933,237 shares of Common Stock
currently outstanding may be deemed "restricted securities" as that term is
defined under the Securities Act of 1933 (the "Act"), and in the future, may be
sold pursuant to a registration under the Act, in compliance with Rule 144 under
the Act, or pursuant to another exemption therefrom. Rule 144 provides, that, in
general, a person holding restricted securities for a period of one year may,
every three months thereafter, sell in brokerage transactions an amount of
shares which does not exceed the greater of one percent of our then outstanding
Common Stock or the average weekly trading volume of the Common Stock during the
four calendar weeks prior to such sale. Rule 144 also permits, under certain
circumstances, the sale of shares without any quantity limitations by a person
who is not an affiliate of ours and was not an affiliate at any time during the
90 day period prior to sale and who has satisfied a two year holding period.
Sales of our Common Stock by certain present stockholders under Rule 144 may, in
the future, have a depressive effect on the market price of our securities. In
addition, the sale of shares by officers and directors and other affiliated
shareholders, may also have a depressive effect on the market for our
securities.

OUR OUTSTANDING OPTIONS AND WARRANTS MAY DEPRESS OUR STOCK PRICE.

         As of August 5, 2002, there were outstanding stock options to purchase
an aggregate of 4,307,099 shares of Common Stock at exercise prices ranging from
$0.01 to $9.125 per share, not all of which are immediately exercisable. As of
August 5, 2002 there were outstanding immediately exercisable warrants to
purchase an aggregate of 2,817,833 shares of Common Stock at exercise prices
ranging from $1.00 to $13.04 per share. In addition, there are outstanding
28,000 shares of our Series B Preferred Stock, which are currently convertible
into an aggregate of 373,333 Shares of Common Stock and 4,000 shares of our
Series C Preferred Stock, which are convertible into an aggregate of 825,593
shares of Common Stock. To the extent that outstanding stock options and
warrants are exercised or the Series B and Series C Preferred Stock is
converted, dilution to our shareholders will occur. Moreover, the terms upon
which we will be able to obtain additional equity capital may be adversely
affected, since the holders of the outstanding options and warrants can be
expected to exercise or convert them at a time when we would, in all likelihood,
be able to obtain any needed capital on terms more favorable to us than the
exercise and conversion terms provided by the outstanding options, warrants and
preferred stock.

IF WE CANNOT OFFSET FUTURE TAXABLE INCOME OUR TAX LIABILITIES WILL INCREASE.

         At June 30, 2001, the date of the most recent fiscal year end for which
we have

                                       19
calculated this amount, we had net operating loss carryforwards ("NOLS") for
federal income tax purposes of approximately $28,100,000 available to offset
future taxable income. Under Section 382 of the Internal Revenue Code of 1986,
as amended, utilization of prior NOLS is limited after an ownership change, as
defined in Section 382, to an annual amount equal to the value of the
corporation's outstanding stock immediately before the date of the ownership
change multiplied by the federal long-term exempt tax rate. Use of our NOLS
could also be limited as a result of grants of stock options under stock option
plans and other events. In the event we achieve profitable operations, any
significant limitation on the utilization of NOLS would have the effect of
increasing our current tax liability.

SINCE THE HOLDERS OF OUR OUTSTANDING SERIES A PREFERRED STOCK CONTROL OUR BOARD
OF DIRECTORS, OTHER SHAREHOLDERS MAY NOT BE ABLE TO INFLUENCE OUR DIRECTION.

         Our Certificate of Incorporation authorizes our Board of Directors to
issue up to 5,000,000 shares of Preferred Stock, from time to time, in one or
more series. The Board of Directors is authorized, without further approval of
the stockholders, to fix the dividend rights and terms, conversion rights,
voting rights, redemption rights and terms, liquidation preferences, and any
other rights, preferences, privileges and restrictions applicable to each new
series of Preferred Stock. We previously established 200 shares of Series A
Preferred Stock which are owned by John Botti and Ira Whitman, our founders and
officers. Currently there are only 100 shares of Series A Preferred Stock
outstanding, all of which are owned by Mr. Botti. The Series A Preferred Stock
entitles the holders to elect a majority of the Board of Directors. The
existence of such stock could adversely affect the voting power of the holders
of Common Stock and, under certain circumstances, make it more difficult for a
third party to gain control of us, discourage bids for the Common Stock at a
premium, or otherwise adversely affect the market price of the Common Stock. In
connection with our recent sale of Series C Preferred Stock, the holder of the
Series A Preferred Stock agreed not to exercise these rights unless we are
current in meeting our dividend obligations and the shares of Common Stock
issuable upon conversion or payable as dividends are not restricted from public
distribution in the United States. As of August 5, 2002, there are outstanding
4,000 shares of our Series C Preferred Stock. In addition, we issued 50,000
shares of our Series B Preferred Stock in our October, 1999 private offering, of
which 28,000 shares are outstanding as of August 5, 2002.

                                 USE OF PROCEEDS

         We will not receive any of the proceeds from the sale of the common
stock offered hereby, but will receive proceeds from the exercise of stock
options issued under the Non- Executive Director Plan. Any funds received in
connection with the exercise of these securities will be used for working
capital purposes.

                                       20
SELLING SECURITY HOLDERS

         The shares offered for resale under this Re-offer Prospectus are being
registered for reoffers and resales by selling stockholders of Authentidate
Holding Corp. who have and may in the future acquire such shares under the 2001
Non-Executive Director Stock Option Plan. Such persons may resell all, a
portion, or none of such shares. The selling stockholders named below are
directors of Authentidate Holding Corp. who may acquire shares of common stock
under the 2001 Non-Executive Director Stock Option Plan and are eligible to
resell any such shares of common stock, regardless of whether they have any
present intent to do so.
SHARES/OPTION          PERCENTAGE OF
                                 SHARES/OPTION SHARES           OPTION             SHARES                 SHARES
         NAME OF                  BENEFICIALLY OWNED             SHARES          OWNED AFTER            OWNED AFTER
 SELLING SECURITY HOLDER(2)       PRIOR TO OFFERING (4)         OFFERED (3)        OFFERING             OFFERING (1)
J. Edward Sheridan                     0/50,000                   10,000            0/50,000                  **
Charles C. Johnston                  48,570/70,000                10,000          48,570/70,000               **
Steven Kriegsman                       0/40,000                   10,000            0/40,000                  **
- ------------------------------
**       Percentage is less than 1%.

(1)      Percentage based on 20,469,480 shares outstanding.

(2)      Each holder is a non-executive director of Authentidate Holding Corp.

(3)      Shares offered pursuant to this prospectus are underlying options to be
         granted to listed holders as of September 1, 2002. Each listed holder
         will be granted options to purchase 10,000 shares as of September 1,
         2002, pursuant to the terms of the 2001 Non-Executive Director Stock
         Option Plan.

(4)      Listed amounts do not include shares underlying options to be granted
         as described in note 3, above.

         The 2001 Director Plan is administered by the Board or a committee of
the Board (the "Committee") which shall at all times consist of not less than
two officers of Authentidate who are not entitled to participate in the 2001
Director Plan, to be appointed by the Board and to serve at the pleasure of the
Board. Options are granted only to non-executive directors serving on the Board
and Advisors serving on the Advisory Boards of Authentidate. The 2001
Non-Executive Director Plan was approved by the Board of Directors and submitted
to and approved by the shareholders at the Annual Meeting held on January 24,
2002.

         Under the 2001 Non-Executive Director Plan, each new non-executive
director to the Board of Directors is entitled to receive an Option to purchase
20,000 shares of Common Stock. Commencing on September 1, 2002, an Option to
purchase 10,000 shares of Common Stock will be granted to each non-executive
director and thereafter on September 1st of each year, pro rata, based on the
time the director has served in such capacity during the previous year. Each
person who is appointed as an Advisor on an Advisory Board established or
maintained by Authentidate shall, upon such appointment and on each anniversary
of the effective date of his appointment, receive an option to purchase 5,000
shares of our Common Stock. Advisors who are also chairmen of such Advisory
Board may be granted options to purchase 7,500 shares, on the terms and
conditions set forth herein.

         It is the intent of Authentidate that the 2001 Non-Executive Director
Plan and any award granted thereunder satisfy and be interpreted in a manner
that satisfies the applicable requirements of Rule 16b-3. This is so that such
persons will be entitled to the benefits of Rule 16b-3 or other exemptive rules
under Section 16 of the 1934 Act and will not be subjected to liability
thereunder.

                                       21
PLAN OF DISTRIBUTION

         The common stock covered by this prospectus, including the shares
underlying the options which will be issued by Authentidate Holding Corp. upon
the exercise of such securities by the holders thereof, may be offered and sold
from time to time by the selling security holders, and pledgees, donees,
transferees or other successors in interest selling shares received after the
date of this prospectus from the selling security holders as a pledge, gift or
other non-sale related transfer. The shares of common stock covered by this
prospectus may be sold from time to time directly by any selling security holder
or any transferees, or alternatively, through underwriters, broker-dealers or
agents, including in one or more of the following transactions:

- -        on the Nasdaq Stock Market;

- -        on the over the counter market;

- -        in transactions other than on the Nasdaq Stock Market or over the
         counter market, such as private resales;

- -        in connection with short sales;

- -        by pledge to secure debts and other obligations;

- -        in connection with the writing of options, in hedge transactions, and
         in settlement of other transactions in standardized or over-the-counter
         options;

- -        in a combination of any of the above transactions; or

- -        pursuant to Rule 144 under the Securities Act, assuming the
         availability of an exemption from registration.

         The selling security holders may sell their shares at market prices
prevailing at the time of sale, at prices related to prevailing market prices,
at negotiated prices, or at fixed prices. In addition, such sales may be
effected in transactions which may involve block trades or transactions in which
the broker acts as agent for the seller and the buyer.

         In connection with sales of the shares of common stock, any selling
security holder may:

- -        enter into hedging transactions with broker-dealers, which may in turn
         engage in short sales of the shares of common stock issuable upon the
         exercise of the options in the course of hedging the positions they
         assume;

- -        sell short and deliver shares of common stock issuable upon the
         exercise of the options to close out the short positions; or

- -        loan or pledge shares of common stock issuable upon the exercise of the
         options to broker-dealers that in turn may sell the securities.

         The selling security holders and any broker-dealers, agents or
underwriters that participate with the selling security holders in the
distribution of the shares of common stock covered by this prospectus may be
deemed to be "underwriters" within the meaning of the Securities Act, in which
event any commissions received by these broker-dealers, agents or underwriters
and any profits realized by the selling security holders on the resales of the
shares may be deemed to be underwriting commissions or discounts under the
Securities Act. Broker-dealers that are used to sell shares will either receive
discounts or commissions from the selling security holders, or will receive
commissions from the purchasers for whom they acted as agents. The selling
security holders may agree to indemnify any broker-dealer or agent that
participates in transactions involving sales of the shares against certain
liabilities, including

                                       22
liabilities arising under the Securities Act.

         In addition, each selling security holder will be subject to applicable
provisions of the Exchange Act of 1934 and the associated rules and regulations
under the Exchange Act of 1934, including Regulation M, which provisions may
limit the timing of purchases and sales of shares of our common stock by the
selling security holders.

         We will make copies of this prospectus available to the selling
security holders and have informed them of the need for delivery of copies of
this prospectus to purchasers at or prior to the time of any sale of the shares.
We will file a supplement to this prospectus, if required, pursuant to Rule
424(b) under the Securities Act of 1933 upon being notified by a selling
security holder that any material arrangement has been entered into with a
broker-dealer for the sale of shares through a block trade, special offering,
exchange distribution or secondary distribution or a purchase by a broker or
dealer.

         There can be no assurance that the selling security holders will sell
all or any of the common stock.

         The selling security holders and us have agreed to customary
indemnification obligations with respect to the sale of common stock by use of
this prospectus.

                                       23
REPORTS TO SHAREHOLDERS

         We distribute annual reports to our stockholders, including audited
financial statements, and will provide such other reports as management may deem
necessary or appropriate to keep stockholders informed of our company's
operations.

                                  LEGAL MATTERS

         The legality of the offering of the shares will be passed upon for us
by Goldstein & DiGioia, LLP, 369 Lexington Avenue, New York, New York l00l7.
Members of the firm, or companies owned by affiliates of the members, own in the
aggregate approximately 70,000 shares of the common stock of Authentidate
Holding Corp., which shares are not covered by this prospectus.

                                     EXPERTS

         The financial statements incorporated in this Prospectus by reference
to the Annual Report on Form 10-K, as amended, for the year ended June 30, 2001
have been so incorporated in reliance on the report of PricewaterhouseCoopers
LLP, independent accountants, given on the authority of said firm as experts in
auditing and accounting.

                             ADDITIONAL INFORMATION

         We have filed a Registration Statement under the Act with the
Securities and Exchange Commission, with respect to the securities offered by
this prospectus. This prospectus does not contain all of the information set
forth in the registration statement. For further information with respect to our
company and such securities, reference is made to the registration statement and
to the exhibits and schedules filed therewith. Each statement made in this
prospectus referring to a document filed as an exhibit to the registration
statement is qualified by reference to the exhibit for a complete statement of
its terms and conditions. The registration statement, including exhibits
thereto, may be inspected without charge to anyone at the office of the
Commission, and copies of all or any part thereof may be obtained from the
Commission's principal office in Washington, D.C. upon payment of the
Commission's charge for copying.

                                       24
FORWARD LOOKING STATEMENTS

         Certain statements in this Prospectus constitute "forward-looking
statements" within the meaning of the Private Securities Litigation Reform Act
of 1995. We desire to avail ourselves of certain "safe harbor" provisions of the
1995 Reform Act and are therefore including this special note to enable us to do
so. Forward-looking statements included in this Prospectus or hereafter included
in other publicly available documents filed with the Securities and Exchange
Commission, reports to our stockholders and other publicly available statements
issued or released by us involve known and unknown risks, uncertainties, and
other factors which could cause our actual results, performance (financial or
operating) or achievements to differ from the future results, performance
(financial or operating) achievements expressed or implied by those forward
looking statements. These future results are based upon management's best
estimates of current conditions and the most recent results of our operations.
The statements appear in a number of places in this Prospectus and include
statements regarding our intent, belief or current expectations, and those of
our directors or officers with respect to: (i) future revenues,(ii) product
development, (iii) success in implementing the Authentidate business plan, (iv)
the document imaging system industry, and (v) other matters. Our actual results
could differ materially from those anticipated in the forward looking statements
as a result of certain factors, including those discussed throughout this
Prospectus. These risks include, but are not limited to, risks associated with
recent and accumulated losses, competition, conflicts of interest, limited
operating history, dependence upon one product line, and other risks detailed in
this Prospectus and our Securities and Exchange Commission filings, including
our Annual Report on Form 10-K, Quarterly Reports on Form 10-Q, as well as
recently filed Reports on Form 8-K, if any, each of which could adversely affect
our business and the accuracy of the forward looking statements contained
herein.

                                       25
PART II

                   INFORMATION NOT REQUIRED IN THE PROSPECTUS

ITEM 3. INCORPORATION OF CERTAIN DOCUMENTS BY REFERENCE

         The following documents, heretofore filed by Authentidate Holding Corp.
with the Commission pursuant to the Exchange Act, are hereby incorporated by
reference, except as superseded or modified herein:

         1.       Our Annual Report on Form 10-K, as amended, for the fiscal
                  year ended June 30, 2001.

         2.       Our Quarterly Reports on Form 10-Q for the fiscal quarters
                  ended September 30, 2001, December 31, 2001 and March 31,
                  2002.

         3.       Our Reports on Form 8-K dated November 29, 2001, March 15,
                  2002, May 9, 2002, August 5, 2002 and August 6, 2002.

         4.       Our Proxy Statement for our Annual Meeting of Shareholders
                  held on January 24, 2002.

         5.       A description of our common stock contained in our
                  registration statement on Form 8-A filed April 17, 2000.

         All documents that we file subsequent to the date of this Prospectus
pursuant to Section 13(a), 13(c), 14 or 15(d) of the Exchange Act and prior to
the filing of a post-effective amendment which indicates that all Shares offered
hereby have been sold or which deregisters all Shares then remaining unsold,
shall be deemed to be incorporated by reference in this Registration Statement
and Prospectus and to be a part hereof from the date of filing of such
documents. Any statement contained in a document incorporated or deemed to be
incorporated by reference herein shall be deemed modified or superseded for
purposes of this Registration Statement and Prospectus to the extent that a
statement contained herein or in any other subsequently filed document which
also is or is deemed to be incorporated by reference herein modifies or
supersedes such statement. Any such statement so modified or superseded shall
not be deemed, except as so modified or superseded, to constitute a part of the
Registration Statement of which this Prospectus forms a part. We will provide
without charge to each person to whom a copy of this Prospectus is delivered,
upon the written or oral request of any such person, a copy of any document
described above (other than exhibits). Requests for such copies should be
directed to Authentidate Holding Corp., 2165 Technology Drive, Schenectady, New
York 12308, telephone (518) 346-7799, Attention: Chief Financial Officer.

ITEM 4.  DESCRIPTION OF SECURITIES.

         Not Applicable.

ITEM 5.  INTERESTS OF NAMED EXPERTS AND COUNSEL.

         Not Applicable.

                                       26
ITEM 6.  INDEMNIFICATION OF DIRECTORS AND OFFICERS.

         The General Corporation Law of Delaware provides generally that a
corporation may indemnify any person who was or is a party to or is threatened
to be made a party to any threatened, pending or completed action, suit or
proceeding, whether civil, criminal, administrative, or investigative in nature,
by reason of the fact that he is or was a director, officer, employee or agent
of the corporation, or is or was serving at the request of the corporation as a
director, officer, employee or agent of another corporation, partnership, joint
venture, trust or other enterprise, against expenses (including attorneys' fees)
and, in a proceeding not by or in the right of the corporation, judgments, fines
and amounts paid in settlement, actually and reasonably incurred by him in
connection with such suit or proceeding, if he acted in good faith and in a
manner believed to be in or not opposed to the best interests of the
corporation, and, with respect to any criminal action or proceeding, had no
reason to believe his conduct was unlawful. Delaware law further provides that a
corporation will not indemnify any person against expenses incurred in
connection with an action by or in the right of the corporation if such person
shall have been adjudged to be liable for negligence or misconduct in the
performance of his duty to the corporation unless and only to the extent that
the court in which such action or suit was brought shall determine that, despite
the adjudication of liability but in view of all the circumstances of the case,
such person is fairly and reasonably entitled to indemnity for the expenses
which such court shall deem proper.

         Our By-Laws provide for indemnification of our officers and directors
to the greatest extent permitted by Delaware law for any and all fees, costs and
expenses incurred in connection with any action or proceeding, civil or
criminal, commenced or threatened, arising out of services by or on behalf of
us, providing such officer's or director's acts were not committed in bad faith.
The By-Laws also provide for advancing funds to pay for anticipated costs and
authorizes the Board to enter into an indemnification agreement with each
officer or director.

         In accordance with Delaware law, our Certificate of Incorporation
contains provisions eliminating the personal liability of directors, except for
(i) breaches of a director's fiduciary duty of loyalty to us or to our
stockholders, (ii) acts or omissions not in good faith or which involve
intentional misconduct or a knowing violation of the law, and (iii) any
transaction in which a director receives an improper personal benefit. These
provisions only pertain to breaches of duty by directors as such, and not in any
other corporate capacity, e.g., as an officer. As a result of the inclusion of
such provisions, neither Authentidate Holding Corp. nor our stockholders may be
able to recover monetary damages against directors for actions taken by them
which are ultimately found to have constituted negligence or gross negligence,
or which are ultimately found to have been in violation of their fiduciary
duties, although it may be possible to obtain injunctive or equitable relief
with respect to such actions. If equitable remedies are found not to be
available to stockholders in any particular case, stockholders may not have an
effective remedy against the challenged conduct.

         We have entered into Indemnification Agreements with each of our
directors and officers (the "Indemnitees") pursuant to which we have agreed to
provide for indemnification, to the fullest extent permitted by law and our
By-Laws, against any and all expenses, judgments, fines, penalties and amounts
paid in settlement arising out of any claim in connection with any event,
occurrence or circumstance related to such individual serving as a director or
officer of us. Such indemnification includes the advance of expenses to the
Indemnitees (including the payment of funds in trust therefor under certain
circumstances) and is subject to there not having been determined that the
Indemnitee would not be permitted to be indemnified under applicable law. The
rights of indemnification are in addition to any other rights which the
Indemnitees may have

                                       27
under our Certificate of Incorporation, By-Laws, the Delaware General
Corporation Law or otherwise.

ITEM 7.  EXEMPTION FROM REGISTRATION CLAIMED.

         Not Applicable

ITEM 8.  EXHIBITS.

         The exhibits designated with (*) are filed herewith. All other exhibits
have been previously filed with the Commission and, pursuant to 17 C.F.R. Secs.
201.24 and 240.12b- 32, are incorporated by reference to the document referenced
in brackets following the description of such exhibits.
EXHIBIT
NO.               DESCRIPTION
- ---               -----------
4.1               Form of Common Stock Certificate (Exhibit 4.1 to Registration Statement on
                  Form S-18, File No. 33-46246-NY)

5.*               Opinion of Goldstein & DiGioia, LLP re legality of shares offered.

23.1*             Consent of PricewaterhouseCoopers, LLP.

23.2*             Consent of Goldstein & DiGioia, LLP, contained in Exhibit 5.

99.1              2001 Non-Executive Director Stock Option Plan (filed as Exhibit 1 to Definitive
                  Proxy Statement dated December 18, 2001 as filed with the Securities and
                  Exchange Commission).
ITEM 9.  UNDERTAKINGS

We hereby undertake:

A.       (1) To file, during any period in which offers or sales are being made,
a post-effective amendment to this registration statement:

                  (i) To include any prospectus required by Section 10(a)(3) of
the Securities Act of 1933;

                  (ii) To reflect in the prospectus any facts or events arising
after the effective date of the registration statement (or the most recent
post-effective amendment thereto) which, individually or in the aggregate,
represent a fundamental change in the information set forth in the Registration
Statement;

                  (iii) To include any material information with respect to the
plan of distribution not previously disclosed in the registration statement or
any material change to such information in the registration statement;

         (2) That, for the purpose of determining any liability under the
Securities Act of 1933,

                                       28
each such post-effective amendment shall be deemed to be a new registration
statement relating to the securities offered therein, and the offering of such
securities at that time shall be deemed to be the initial bona fide offering
thereof.

         (3) To remove from registration by means of a post-effective amendment
any of the securities being registered which remain unsold at the termination of
the offering.

         (4) (i) For the purpose of determining any liability under the
Securities Act of 1933, the information omitted from the form of prospectus
filed as part of this Registration Statement in reliance upon Rule 430A and
contained in the form of prospectus filed by the Registrant pursuant to Rule
424(b)(1) or (4) or 497(h) under the Securities Act shall be deemed to be part
of the Registration Statement as of the time it was declared effective.

                  (ii) For the purpose of determining any liability under the
Securities Act of 1933, each post-effective amendment that contains a form of
prospectus shall be deemed to be a new registration statement relating to the
securities offered therein, and the offering of such securities at that time
shall be deemed to be the initial bona fide offering thereof.

         (5) For purposes of determining any liability under the Securities Act
of 1933, each filing of our annual report pursuant to Section 13(a) or Section
15(d) of the Securities Exchange Act of 1934 (and, where applicable, each filing
of an employee benefit plan's annual report pursuant to Section 15(d) of the
Securities Exchange Act of 1934) that is incorporated by reference in the
registration statement shall be deemed to be a new registration statement
relating to the securities offered therein, and the offering of such securities
at that time shall be deemed to be the initial bona fide offering thereof.

B. Insofar as indemnification for liabilities arising under the Securities Act
of 1933 may be permitted to directors, officers and controlling persons of the
Registrant pursuant to the foregoing provisions, or otherwise, the Registrant
has been advised that in the opinion of the Securities and Exchange Commission
such indemnification is against public policy as expressed in the Act and is,
therefore, unenforceable. In the event that a claim for indemnification against
such liabilities (other than the payment by the registrant of expenses incurred
or paid by a director, officer or controlling person of the registrant in the
successful defense of any action, suit or proceeding) is asserted by such
director, officer or controlling person in connection with the securities being
registered, the registrant will, unless in the opinion of its counsel the matter
has been settled by controlling precedent, submit to a court of appropriate
jurisdiction the question whether such indemnification by it is against public
policy as expressed in the Act and will be governed by the final adjudication of
such issue.

                                       29
SIGNATURES

         Pursuant to the requirements of the Securities Act of 1933, we certify
that we have reasonable grounds to believe that we meet all of the requirements
for filing on Form S-8 and have duly caused this Registration Statement to be
signed on our behalf by the undersigned, thereunto duly authorized, in the City
of Schenectady, New York, on August 6, 2002.

                             AUTHENTIDATE HOLDING CORP.

                             By:  /s/ JOHN T. BOTTI
                                  ----------------------------------------
                                  John T. Botti
                                  Chief Executive Officer, Chairman of the Board
                                   and President

                  KNOW ALL MEN BY THESE PRESENTS, that each person whose
signature appears below substitutes and appoints John Botti his true and lawful
attorney-in-fact and agents, with full power of substitution and resubstitution,
for him and in his name, place and stead, in any and all capacities, to sign any
and all amendments (including post-effective amendments) to this Registration
Statement, and to file the same, with all exhibits thereto, and other documents
in connection therewith, with the Securities and Exchange Commission, granting
unto said attorney-in-fact and agent full power and authority to do and perform
each and every act and thing requisite and necessary to be don in and about the
premises, as fully to all intents and purposes as he might or could do in
person, hereby ratifying and confirming all that said attorney-in-fact and agent
or his substitute, may lawfully do or cause to be done by virtue hereof.

                  Pursuant to the requirements of the Securities Exchange Act of
1933, this registration statement has been signed below by the following persons
on our behalf and in the capacities and on the dates indicated.
NAME                                        TITLE                                              DATE
/s/John T. Botti                            Chairman of the Board, President                   August 6, 2002
- ----------------                            and Chief Executive Officer
John T. Botti

/s/ Robert Van Naarden                      Director and Chief Executive                       August 12, 2002
- ----------------------                      Officer, Authentidate, Inc.
Robert Van Naarden

/s/Steven A. Kreigsman                      Director                                           August 8, 2002
- ----------------------
Steven A. Kriegsman

/s/J. Edward Sheridan                       Director                                           August 6, 2002
- ---------------------
J. Edward Sheridan

/s/Charles C. Johnston                      Director                                           August 6, 2002
- ----------------------
Charles C. Johnston
30
/s/Dennis H. Bunt                           Chief Financial Officer and                        August 7, 2002
- -----------------                           Principal Accounting Officer
Dennis H. Bunt

/s/ Thomas Franceski                        Vice President, Technology                         August 6, 2002
- --------------------                        Products Group
Thomas Franceski
31