<PAGE>
 
    As filed with the Securities and Exchange Commission on March 31, 1999
                                                           Registration No. 333-
================================================================================

                      SECURITIES AND EXCHANGE COMMISSION
                            Washington, D.C. 20549

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

                                   FORM S-8

                            REGISTRATION STATEMENT
                                     Under
                          The Securities Act of 1933

                    PLATINUM technology International, inc.
            (Exact name of registrant as specified in its charter)

               Delaware                                  36-3509662
   (State or other jurisdiction of              (IRS Employer Identification
  of incorporation or organization)                        Number)

           1815 South Meyers Road, Oakbrook Terrace, Illinois 60181
         (Address, Including Zip Code, of Principal Executive Offices)

           Memco Software Ltd. 1996 Stock Option and Incentive Plan
         Memco Software Ltd. 1996 Stock Option and Incentive Plan (II)
        Memco Software Ltd. 1997 Stock Option and Incentive Plan (III)
         Memco Software Ltd. 1998 Stock Option and Incentive Plan (IV)
          Network Information Technology, Inc. 1993 Stock Option Plan
        Network Information Technology, Inc. 1997 Equity Incentive Plan
                           (Full Title of the Plans)

                             Andrew J. Filipowski
   1815 South Meyers Road, Oakbrook Terrace, Illinois 60181, (630) 620-5000
(Name, Address, Including Zip Code, and Telephone Number, Including Area Code,
                             of Agent for Service)

                                  Copies to:
                            Matthew S. Brown, Esq.
                             Linda J. Wight, Esq.
                             Katten Muchin & Zavis
                           525 W. Monroe, Suite 1600
                            Chicago, IL  60661-3693
                          Fax Number: (312) 902-1061

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

                        CALCULATION OF REGISTRATION FEE
<TABLE>
<CAPTION>
====================================================================================================================================
                                                                        Proposed maximum      Proposed maximum
                                                                         offering price      aggregate offering         Amount of
Title of securities to be registered    Amount to be registered(1)          per share               price           registration fee
------------------------------------------------------------------------------------------------------------------------------------
<S>                                     <C>                            <C>                  <C>                     <C>
Common Stock, $.001 par value.........      3,328,112 shares(2)            $11.101(2)          $36,945,404(2)            $10,271
====================================================================================================================================
</TABLE>

(1) Also includes associated rights (the "Rights") to purchase 1/100 of a share
    of Series A Participating Preferred Stock, par value $.01 per share, of
    PLATINUM technology International, inc. The Rights initially attached to and
    trade with PLATINUM Common Stock. The value attributable to such Rights, if
    any, is reflected in the market price of the PLATINUM Common Stock.
(2) Represents the number of shares issuable upon exercise of outstanding
    options under the Memco Software Ltd. 1996 Stock Option and Incentive Plan,
    Memco Software Ltd. 1996 Stock Option and Incentive Plan (II), Memco
    Software Ltd. 1997 Stock Option and Incentive Plan (III), Memco Software
    Ltd. 1998 Stock Option and Incentive Plan (IV), the Network Information
    Technology, Inc. 1993 Stock Option Plan and the Network Information
    Technology, Inc. 1997 Equity Incentive Plan (the "Memco Plans"). Pursuant to
    Rule 457(h)(i) the dollar amounts are based upon the weighted average
    exercise price of the shares subject to outstanding options under the Memco
    Plans.

<PAGE>
 
                                    PART II
              INFORMATION REQUIRED IN THE REGISTRATION STATEMENT
Item 3.  Incorporation of Documents by Reference.

     The following documents have been filed by PLATINUM technology
International, inc. ("the Company") with the Commission under the Securities
Exchange Act of 1934, as amended (the "Exchange Act"), and are incorporated in
this Registration Statement by reference:

     1.   The Company's Annual Report on Form 10-K for the year ended December
          31, 1997;

     2.   The Company's Quarterly Reports on Form 10-Q for the quarters ended
          March 31, 1998, June 30, 1998, and September 30, 1998 (as amended by
          the Quarterly Report on Form 10-Q/A dated February 2, 1999);

     3.   The Company's Current Reports on Form 8-K dated January 27, 1998,
          March 3, 1998, April 16, 1998, April 21, 1998 (as amended by the
          Current Report on Form 8-K/A dated May 6, 1998), May 28, 1998, July
          14, 1998, August 4, 1998, August 13, 1998, October 15, 1998, January
          19, 1999, January 26, 1999, February 9, 1999 and February 23, 1999;

     4.   The description of the Common Stock contained in the Company's
          Registration Statement on Form 8-A filed March 7, 1991 pursuant to
          Section 12 of the Exchange Act and all amendments thereto and reports
          filed for the purpose of updating such description; and

     5.   The description of the preferred stock purchase rights contained in
          the Company's Registration Statement on Form 8-A filed December 26,
          1995 pursuant to Section 12 of the Exchange Act and all amendments
          thereto and reports filed for the purpose of updating such
          description.

     In addition, all documents filed by the Company pursuant to Sections 13(a),
13(c), 14 and 15(d) of the Exchange Act, subsequent to the date hereof and prior
to the filing of a post-effective amendment indicating that all securities
offered pursuant to this Registration Statement have been sold or deregistering
all such securities then remaining unsold, shall be deemed to be incorporated by
reference herein and to be 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 to be modified or superseded
for purposes of this Registration Statement to the extent that a statement
contained herein or in any subsequently filed document which also is or is
deemed to be incorporated by reference herein modifies or supersedes such
statement.

Item 4.  Description of Securities.
     Not Applicable.

Item 5.  Interests of Named Experts and Counsel.
     Not Applicable.

Item 6.  Indemnification of Directors and Officers.

     Article Ten of the Company's Restated Certificate of Incorporation provides
that the Company shall indemnify its directors to the full extent permitted by
the Delaware General Corporation Law and may indemnify its officers to such
extent, except that the Company shall not be obligated to indemnify any such
person (i) with respect to proceedings, claims or actions initiated or brought
voluntarily by any such person and not by way of defense, or (ii) for any
amounts paid in settlement of an action indemnified against by the Company
without the prior written consent of the Company. With the approval of its
stockholders, the Company has entered into indemnity agreements with each of its
directors and certain of its officers. These agreements may require the Company,
among other things, to indemnify such officers and directors against certain
liabilities that may arise by reason of their status or service as directors or
officers, to advance expenses to them as they are incurred, provided that they
undertake to repay the amount advanced if it is ultimately determined by a court
that they are not entitled to indemnification, and to obtain directors' and
officers' liability insurance if available on reasonable terms.

     In addition, Article Nine of the Company's Restated Certificate of
Incorporation provides that a director of the Company shall not be personally
liable to the Company or its stockholders for monetary damages for breach of his
or her fiduciary duty as a director, except for liability (i) for any breach of
the


                                       2
<PAGE>
 
director's duty of loyalty to the Company or its stockholders, (ii) for acts or
omissions not in good faith or which involve intentional misconduct or a knowing
violation of law, (iii) under Section 174 of the General Corporation Law of the
State of Delaware, or (iv) for any transaction from which the director derives
an improper personal benefit.

     Reference is made to Section 145 of the General Corporation Law of the
State of Delaware which provides for indemnification of directors and officers
in certain circumstances.

     The Company has purchased an insurance policy under which it is entitled to
be reimbursed for certain indemnity payments it is required or permitted to make
to its directors and officers.

Item 7.  Exemption from Registration Claimed.
     Not Applicable.

Item 8.  Exhibits.
 
      4.1  Restated Certificate of Incorporation of the Company, as amended
           (incorporated by reference to the Company's Registration Statement on
           Form S-4, Registration No. 333-71637).

      4.2  Bylaws of the Company, as amended (incorporated by reference to the
           Company's Registration Statement on Form S-4, Registration No.
           33-71637).

      4.3  Memco Software Ltd. 1996 Stock Option and Incentive Plan
           (incorporated by reference to Memco's Registration Statement on Form
           S-8, Registration No. 333-6060).

      4.4  Memco Software Ltd. 1996 Stock Option and Incentive Plan (II)
           (incorporated by reference to Memco's Registration Statement on Form
           S-8, Registration No. 333-6060).

      4.5  Memco Software Ltd. 1997 Stock Option and Incentive Plan (III)
           (incorporated by reference to Memco's Registration Statement on Form
           S-8, Registration No. 333-8478).

      4.6  Memco Software Ltd. 1998 Stock Option and Incentive Plan (IV).

      4.7  Network Information Technology Inc. 1993 Stock Option Plan
           (incorporated by reference to Memco's Registration Statement on Form
           S-8, Registration No. 333-8854).

      4.8  Network Information Technology, Inc. 1997 Equity Incentive Plan
           (incorporated by reference to Memco's Registration Statement on Form
           S-8, Registration No. 333-8854).

      4.9  Form of Stock Option Agreement for the Memco Software Ltd. 1997 Stock
           Option and Incentive Plan (III).

      4.10 Form of Stock Option Agreement for the Memco Software Ltd. 1998 Stock
           Option and Incentive Plan (IV).

      4.11 Rights Agreement dated as of December 21, 1995, between the Company
           and Harris Trust and Savings Bank (incorporated by reference to
           Exhibit 1 to the Company's Registration Statement on Form 8-A, filed
           December 26, 1995).

      5    Opinion of counsel as to legality of shares of Common Stock being
           offered (including consent).

      15   Acknowledgement of Certified Public Accountants Regarding Independent
           Auditor's Review Report.

     23.1  Consent of KPMG LLP.

     23.2  Consent of Ernst & Young LLP.

     23.3  Consent of Arthur Andersen LLP.

     23.4  Consent of Katten Muchin & Zavis (included in their opinion filed as
           Exhibit 5 herein).

     24    Power of Attorney (included on the signature page of this
           Registration Statement).

                                       3
<PAGE>

Item 9.  Undertakings.
     1.   The Company hereby undertakes:

          (a)  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 thereof) which, individually, or in
          the aggregate, represent a fundamental change in the information set
          forth in the Registration Statement. Notwithstanding the foregoing,
          any increase or decrease in volume of securities offered (if the total
          dollar value of securities offered would not exceed that which was
          registered) and any deviation from the low or high end of the
          estimated maximum offering range may be reflected in the form of
          prospectus filed with the Commission pursuant to Rule 424(b) if, in
          the aggregate, the changes in volume and price represent no more than
          a 20 percent change in the maximum aggregate offering price set forth
          in the "Calculation of Registration Fee" table in the effective
          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;

     provided, however, that paragraphs (a)(i) and (a)(ii) do not apply if the
     information required to be included in a post-effective amendment by those
     paragraphs is contained in periodic reports filed with or furnished to the
     Commission by the Company pursuant to Section 13 or Section 15(d) of the
     Exchange Act that are incorporated by reference in the Registration
     Statement.

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

          (c)  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.

     2.   The Company hereby undertakes that, for the purpose of determining any
liability under the Securities Act of 1933, each filing of the Company's annual
report pursuant to Section 13(a) or Section 15(d) of the Exchange Act 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.

     3.   Insofar as indemnification for liabilities arising under the
Securities Act of 1933 may be permitted to directors, officers and controlling
persons of the Company and affiliated companies pursuant to the provisions
described in Item 6 above, or otherwise, the Company has been informed that in
the opinion of the Commission such indemnification is against public policy as
expressed in the Securities Act of 1933 and is therefore unenforceable. In the
event that a claim for indemnification against such liabilities (other than the
payment by the Company of expenses incurred or paid by a director, officer or
controlling person of the Company 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 Company 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 Securities
Act of 1933 and will be governed by the final adjudication of such issue.


                                       4
<PAGE>
 
                                  SIGNATURES

     Pursuant to the requirements of the Securities Act of 1933, the Company
certifies that it has reasonable grounds to believe that it meets all of the
requirements for filing on Form S-8 and has duly caused this Registration
Statement to be signed on its behalf by the undersigned, thereunto duly
authorized, in the City of Oakbrook Terrace, State of Illinois, on this 31st day
of March, 1999.

                                   PLATINUM technology International, inc.

                                   By: /s/  ANDREW J. FILIPOWSKI
                                      ----------------------------------------
                                       Andrew J. Filipowski
                                       President and Chief Executive Officer


                               POWER OF ATTORNEY

     Each person whose signature appears below hereby constitutes and appoints
Andrew J. Filipowski, Michael P. Cullinane, and Matthew S. Brown, and each of
them, his true and lawful attorneys-in-fact and agents, with full power of
substitution, to sign on his behalf, individually and in each capacity stated
below, all amendments and post-effective amendments to this Registration
Statement on Form S-8 and to file the same, with all exhibits thereto and any
other documents in connection therewith, with the Securities and Exchange
Commission under the Securities Act of 1933, granting unto said attorneys-in-
fact and agents full power and authority to do and perform each and every act
and thing requisite and necessary to be done in and about the premises, as fully
and to all intents and purposes as each might or could do in person, hereby
ratifying and confirming each act that said attorneys-in-fact and agents may
lawfully do or cause to be done by virtue thereof.

     Pursuant to the requirements of the Securities Act of 1933, this
Registration Statement has been signed by the following persons in the
capacities indicated on this 31st day of March, 1999.

<TABLE>
<CAPTION>
Signature                                           Title                         Date
---------                                           -----                         ----
<S>                              <C>
   /s/ ANDREW J. FILIPOWSKI      President, Chief Executive Officer (Principal    March 31, 1999
------------------------------   Executive Officer) and a Director
     Andrew J. Filipowski

   /s/ MICHAEL P. CULLINANE      Executive Vice President, Chief Financial        March 31, 1999
------------------------------   Officer, Treasurer (Principal Financial and
     Michael P. Cullinane        Accounting Officer) and a Director

    /s/ PAUL L. HUMENANSKY       Executive Vice President--Product                March 31, 1999
------------------------------   Development, Chief Operations Officer and a
      Paul L. Humenansky         Director

      /s/ JAMES E. COWIE
------------------------------   Director                                         March 31, 1999
        James E. Cowie


------------------------------   Director                                         
       Steven D. Devick

     /s/ ARTHUR P. FRIGO
------------------------------   Director                                         March 31, 1999
       Arthur P. Frigo

------------------------------   Director                                         
         Gian Fulgoni
</TABLE>


                                       5
<PAGE>
 
Exhibit       Description of Exhibit
 Number       ----------------------
-------

  4.1     Restated Certificate of Incorporation of the Company, as amended
          (incorporated by reference to the Company's Registration Statement on
          Form S-4, Registration No. 333-71637).

  4.2     Bylaws of the Company, as amended (incorporated by reference to the
          Company's Registration Statement on Form S-4, Registration No.
          33-71637).

  4.3     Memco Software Ltd. 1996 Stock Option and Incentive Plan (incorporated
          by reference to Memco's Registration Statement on Form S-8,
          Registration No. 333-6060).

  4.4     Memco Software Ltd. 1996 Stock Option and Incentive Plan (II)
          (incorporated by reference to Memco's Registration Statement on Form 
          S-8, Registration No. 333-6060).

  4.5     Memco Software Ltd. 1997 Stock Option and Incentive Plan (III)
          (incorporated by reference to Memco's Registration Statement on Form 
          S-8, Registration No. 333-8478).

  4.6     Memco Software Ltd. 1998 Stock Option and Incentive Plan (IV).*

  4.7     Network Information Technology Inc. 1993 Stock Option Plan
          (incorporated by reference to Memco's Registration Statement on Form 
          S-8, Registration No. 333-8854).

  4.8     Network Information Technology, Inc. 1997 Equity Incentive Plan
          (incorporated by reference to Memco's Registration Statement on Form 
          S-8, Registration No. 333-8854).

  4.9     Form of Stock Option Agreement for the Memco Software Ltd. 1997 Stock
          Option and Incentive Plan (III).*

  4.10    Form of Stock Option Agreement for the Memco Software Ltd. 1998 Stock
          Option and Incentive Plan (IV).*

  4.11    Rights Agreement dated as of December 21, 1995, between the Company
          and Harris Trust and Savings Bank (incorporated by reference to
          Exhibit 1 to the Company's Registration Statement on Form 8-A, filed
          December 26, 1995).

  5       Opinion of counsel as to legality of shares of Common Stock being
          offered (including consent).*

  15      Acknowledgement of Certified Public Accountants Regarding Independent
          Auditor's Review Report.*

  23.1    Consent of KPMG LLP.*

  23.2    Consent of Ernst & Young LLP.*

  23.3    Consent of Arthur Andersen LLP.*

  23.4    Consent of Katten Muchin & Zavis (included in their opinion filed as
          Exhibit 5 herein).

  24      Power of Attorney (included on the signature page of this Registration
          Statement).
 ---------
* Filed herewith.
                                       6
[{"type": "S-8", "sequence": "1", "description": "FORM S-8", "secsgml_size_bytes": 22677}]
{"company-data": {"conformed-name": "PLATINUM TECHNOLOGY INTERNATIONAL INC", "cik": "0000825703", "assigned-sic": "7372", "irs-number": "363509662", "state-of-incorporation": "DE", "fiscal-year-end": "1231"}, "filing-values": {"form-type": "S-8", "act": "33", "file-number": "333-75323", "film-number": "99581541"}, "business-address": {"street1": "1815 S MEYERS RD", "city": "OAKBROOK TERRACE", "state": "IL", "zip": "60181", "phone": "6306205000"}, "mail-address": {"street1": "1815 S MEYERS RD", "city": "OAKBROOK TERRACE", "state": "IL", "zip": "60181"}, "former-company": {"former-conformed-name": "PLATINUM TECHNOLOGY INC", "date-changed": "19940506"}}
As filed with the Securities and Exchange Commission on March 31, 1999
                                                           Registration No. 333-
================================================================================

                      SECURITIES AND EXCHANGE COMMISSION
                            Washington, D.C. 20549

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

                                   FORM S-8

                            REGISTRATION STATEMENT
                                     Under
                          The Securities Act of 1933

                    PLATINUM technology International, inc.
            (Exact name of registrant as specified in its charter)

               Delaware                                  36-3509662
   (State or other jurisdiction of              (IRS Employer Identification
  of incorporation or organization)                        Number)

           1815 South Meyers Road, Oakbrook Terrace, Illinois 60181
         (Address, Including Zip Code, of Principal Executive Offices)

           Memco Software Ltd. 1996 Stock Option and Incentive Plan
         Memco Software Ltd. 1996 Stock Option and Incentive Plan (II)
        Memco Software Ltd. 1997 Stock Option and Incentive Plan (III)
         Memco Software Ltd. 1998 Stock Option and Incentive Plan (IV)
          Network Information Technology, Inc. 1993 Stock Option Plan
        Network Information Technology, Inc. 1997 Equity Incentive Plan
                           (Full Title of the Plans)

                             Andrew J. Filipowski
   1815 South Meyers Road, Oakbrook Terrace, Illinois 60181, (630) 620-5000
(Name, Address, Including Zip Code, and Telephone Number, Including Area Code,
                             of Agent for Service)

                                  Copies to:
                            Matthew S. Brown, Esq.
                             Linda J. Wight, Esq.
                             Katten Muchin & Zavis
                           525 W. Monroe, Suite 1600
                            Chicago, IL  60661-3693
                          Fax Number: (312) 902-1061

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

                        CALCULATION OF REGISTRATION FEE
====================================================================================================================================
                                                                        Proposed maximum      Proposed maximum
                                                                         offering price      aggregate offering         Amount of
Title of securities to be registered    Amount to be registered(1)          per share               price           registration fee
------------------------------------------------------------------------------------------------------------------------------------
Common Stock, $.001 par value.........      3,328,112 shares(2)            $11.101(2)          $36,945,404(2)            $10,271
====================================================================================================================================
(1) Also includes associated rights (the "Rights") to purchase 1/100 of a share
    of Series A Participating Preferred Stock, par value $.01 per share, of
    PLATINUM technology International, inc. The Rights initially attached to and
    trade with PLATINUM Common Stock. The value attributable to such Rights, if
    any, is reflected in the market price of the PLATINUM Common Stock.
(2) Represents the number of shares issuable upon exercise of outstanding
    options under the Memco Software Ltd. 1996 Stock Option and Incentive Plan,
    Memco Software Ltd. 1996 Stock Option and Incentive Plan (II), Memco
    Software Ltd. 1997 Stock Option and Incentive Plan (III), Memco Software
    Ltd. 1998 Stock Option and Incentive Plan (IV), the Network Information
    Technology, Inc. 1993 Stock Option Plan and the Network Information
    Technology, Inc. 1997 Equity Incentive Plan (the "Memco Plans"). Pursuant to
    Rule 457(h)(i) the dollar amounts are based upon the weighted average
    exercise price of the shares subject to outstanding options under the Memco
    Plans.
PART II
              INFORMATION REQUIRED IN THE REGISTRATION STATEMENT
Item 3.  Incorporation of Documents by Reference.

     The following documents have been filed by PLATINUM technology
International, inc. ("the Company") with the Commission under the Securities
Exchange Act of 1934, as amended (the "Exchange Act"), and are incorporated in
this Registration Statement by reference:

     1.   The Company's Annual Report on Form 10-K for the year ended December
          31, 1997;

     2.   The Company's Quarterly Reports on Form 10-Q for the quarters ended
          March 31, 1998, June 30, 1998, and September 30, 1998 (as amended by
          the Quarterly Report on Form 10-Q/A dated February 2, 1999);

     3.   The Company's Current Reports on Form 8-K dated January 27, 1998,
          March 3, 1998, April 16, 1998, April 21, 1998 (as amended by the
          Current Report on Form 8-K/A dated May 6, 1998), May 28, 1998, July
          14, 1998, August 4, 1998, August 13, 1998, October 15, 1998, January
          19, 1999, January 26, 1999, February 9, 1999 and February 23, 1999;

     4.   The description of the Common Stock contained in the Company's
          Registration Statement on Form 8-A filed March 7, 1991 pursuant to
          Section 12 of the Exchange Act and all amendments thereto and reports
          filed for the purpose of updating such description; and

     5.   The description of the preferred stock purchase rights contained in
          the Company's Registration Statement on Form 8-A filed December 26,
          1995 pursuant to Section 12 of the Exchange Act and all amendments
          thereto and reports filed for the purpose of updating such
          description.

     In addition, all documents filed by the Company pursuant to Sections 13(a),
13(c), 14 and 15(d) of the Exchange Act, subsequent to the date hereof and prior
to the filing of a post-effective amendment indicating that all securities
offered pursuant to this Registration Statement have been sold or deregistering
all such securities then remaining unsold, shall be deemed to be incorporated by
reference herein and to be 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 to be modified or superseded
for purposes of this Registration Statement to the extent that a statement
contained herein or in any subsequently filed document which also is or is
deemed to be incorporated by reference herein modifies or supersedes such
statement.

Item 4.  Description of Securities.
     Not Applicable.

Item 5.  Interests of Named Experts and Counsel.
     Not Applicable.

Item 6.  Indemnification of Directors and Officers.

     Article Ten of the Company's Restated Certificate of Incorporation provides
that the Company shall indemnify its directors to the full extent permitted by
the Delaware General Corporation Law and may indemnify its officers to such
extent, except that the Company shall not be obligated to indemnify any such
person (i) with respect to proceedings, claims or actions initiated or brought
voluntarily by any such person and not by way of defense, or (ii) for any
amounts paid in settlement of an action indemnified against by the Company
without the prior written consent of the Company. With the approval of its
stockholders, the Company has entered into indemnity agreements with each of its
directors and certain of its officers. These agreements may require the Company,
among other things, to indemnify such officers and directors against certain
liabilities that may arise by reason of their status or service as directors or
officers, to advance expenses to them as they are incurred, provided that they
undertake to repay the amount advanced if it is ultimately determined by a court
that they are not entitled to indemnification, and to obtain directors' and
officers' liability insurance if available on reasonable terms.

     In addition, Article Nine of the Company's Restated Certificate of
Incorporation provides that a director of the Company shall not be personally
liable to the Company or its stockholders for monetary damages for breach of his
or her fiduciary duty as a director, except for liability (i) for any breach of
the

                                       2
director's duty of loyalty to the Company or its stockholders, (ii) for acts or
omissions not in good faith or which involve intentional misconduct or a knowing
violation of law, (iii) under Section 174 of the General Corporation Law of the
State of Delaware, or (iv) for any transaction from which the director derives
an improper personal benefit.

     Reference is made to Section 145 of the General Corporation Law of the
State of Delaware which provides for indemnification of directors and officers
in certain circumstances.

     The Company has purchased an insurance policy under which it is entitled to
be reimbursed for certain indemnity payments it is required or permitted to make
to its directors and officers.

Item 7.  Exemption from Registration Claimed.
     Not Applicable.

Item 8.  Exhibits.
 
      4.1  Restated Certificate of Incorporation of the Company, as amended
           (incorporated by reference to the Company's Registration Statement on
           Form S-4, Registration No. 333-71637).

      4.2  Bylaws of the Company, as amended (incorporated by reference to the
           Company's Registration Statement on Form S-4, Registration No.
           33-71637).

      4.3  Memco Software Ltd. 1996 Stock Option and Incentive Plan
           (incorporated by reference to Memco's Registration Statement on Form
           S-8, Registration No. 333-6060).

      4.4  Memco Software Ltd. 1996 Stock Option and Incentive Plan (II)
           (incorporated by reference to Memco's Registration Statement on Form
           S-8, Registration No. 333-6060).

      4.5  Memco Software Ltd. 1997 Stock Option and Incentive Plan (III)
           (incorporated by reference to Memco's Registration Statement on Form
           S-8, Registration No. 333-8478).

      4.6  Memco Software Ltd. 1998 Stock Option and Incentive Plan (IV).

      4.7  Network Information Technology Inc. 1993 Stock Option Plan
           (incorporated by reference to Memco's Registration Statement on Form
           S-8, Registration No. 333-8854).

      4.8  Network Information Technology, Inc. 1997 Equity Incentive Plan
           (incorporated by reference to Memco's Registration Statement on Form
           S-8, Registration No. 333-8854).

      4.9  Form of Stock Option Agreement for the Memco Software Ltd. 1997 Stock
           Option and Incentive Plan (III).

      4.10 Form of Stock Option Agreement for the Memco Software Ltd. 1998 Stock
           Option and Incentive Plan (IV).

      4.11 Rights Agreement dated as of December 21, 1995, between the Company
           and Harris Trust and Savings Bank (incorporated by reference to
           Exhibit 1 to the Company's Registration Statement on Form 8-A, filed
           December 26, 1995).

      5    Opinion of counsel as to legality of shares of Common Stock being
           offered (including consent).

      15   Acknowledgement of Certified Public Accountants Regarding Independent
           Auditor's Review Report.

     23.1  Consent of KPMG LLP.

     23.2  Consent of Ernst & Young LLP.

     23.3  Consent of Arthur Andersen LLP.

     23.4  Consent of Katten Muchin & Zavis (included in their opinion filed as
           Exhibit 5 herein).

     24    Power of Attorney (included on the signature page of this
           Registration Statement).

                                       3
Item 9.  Undertakings.
     1.   The Company hereby undertakes:

          (a)  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 thereof) which, individually, or in
          the aggregate, represent a fundamental change in the information set
          forth in the Registration Statement. Notwithstanding the foregoing,
          any increase or decrease in volume of securities offered (if the total
          dollar value of securities offered would not exceed that which was
          registered) and any deviation from the low or high end of the
          estimated maximum offering range may be reflected in the form of
          prospectus filed with the Commission pursuant to Rule 424(b) if, in
          the aggregate, the changes in volume and price represent no more than
          a 20 percent change in the maximum aggregate offering price set forth
          in the "Calculation of Registration Fee" table in the effective
          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;

     provided, however, that paragraphs (a)(i) and (a)(ii) do not apply if the
     information required to be included in a post-effective amendment by those
     paragraphs is contained in periodic reports filed with or furnished to the
     Commission by the Company pursuant to Section 13 or Section 15(d) of the
     Exchange Act that are incorporated by reference in the Registration
     Statement.

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

          (c)  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.

     2.   The Company hereby undertakes that, for the purpose of determining any
liability under the Securities Act of 1933, each filing of the Company's annual
report pursuant to Section 13(a) or Section 15(d) of the Exchange Act 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.

     3.   Insofar as indemnification for liabilities arising under the
Securities Act of 1933 may be permitted to directors, officers and controlling
persons of the Company and affiliated companies pursuant to the provisions
described in Item 6 above, or otherwise, the Company has been informed that in
the opinion of the Commission such indemnification is against public policy as
expressed in the Securities Act of 1933 and is therefore unenforceable. In the
event that a claim for indemnification against such liabilities (other than the
payment by the Company of expenses incurred or paid by a director, officer or
controlling person of the Company 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 Company 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 Securities
Act of 1933 and will be governed by the final adjudication of such issue.

                                       4
SIGNATURES

     Pursuant to the requirements of the Securities Act of 1933, the Company
certifies that it has reasonable grounds to believe that it meets all of the
requirements for filing on Form S-8 and has duly caused this Registration
Statement to be signed on its behalf by the undersigned, thereunto duly
authorized, in the City of Oakbrook Terrace, State of Illinois, on this 31st day
of March, 1999.

                                   PLATINUM technology International, inc.

                                   By: /s/  ANDREW J. FILIPOWSKI
                                      ----------------------------------------
                                       Andrew J. Filipowski
                                       President and Chief Executive Officer

                               POWER OF ATTORNEY

     Each person whose signature appears below hereby constitutes and appoints
Andrew J. Filipowski, Michael P. Cullinane, and Matthew S. Brown, and each of
them, his true and lawful attorneys-in-fact and agents, with full power of
substitution, to sign on his behalf, individually and in each capacity stated
below, all amendments and post-effective amendments to this Registration
Statement on Form S-8 and to file the same, with all exhibits thereto and any
other documents in connection therewith, with the Securities and Exchange
Commission under the Securities Act of 1933, granting unto said attorneys-in-
fact and agents full power and authority to do and perform each and every act
and thing requisite and necessary to be done in and about the premises, as fully
and to all intents and purposes as each might or could do in person, hereby
ratifying and confirming each act that said attorneys-in-fact and agents may
lawfully do or cause to be done by virtue thereof.

     Pursuant to the requirements of the Securities Act of 1933, this
Registration Statement has been signed by the following persons in the
capacities indicated on this 31st day of March, 1999.
Signature                                           Title                         Date
---------                                           -----                         ----
/s/ ANDREW J. FILIPOWSKI      President, Chief Executive Officer (Principal    March 31, 1999
------------------------------   Executive Officer) and a Director
     Andrew J. Filipowski

   /s/ MICHAEL P. CULLINANE      Executive Vice President, Chief Financial        March 31, 1999
------------------------------   Officer, Treasurer (Principal Financial and
     Michael P. Cullinane        Accounting Officer) and a Director

    /s/ PAUL L. HUMENANSKY       Executive Vice President--Product                March 31, 1999
------------------------------   Development, Chief Operations Officer and a
      Paul L. Humenansky         Director

      /s/ JAMES E. COWIE
------------------------------   Director                                         March 31, 1999
        James E. Cowie

------------------------------   Director                                         
       Steven D. Devick

     /s/ ARTHUR P. FRIGO
------------------------------   Director                                         March 31, 1999
       Arthur P. Frigo

------------------------------   Director                                         
         Gian Fulgoni
5
Exhibit       Description of Exhibit
 Number       ----------------------
-------

  4.1     Restated Certificate of Incorporation of the Company, as amended
          (incorporated by reference to the Company's Registration Statement on
          Form S-4, Registration No. 333-71637).

  4.2     Bylaws of the Company, as amended (incorporated by reference to the
          Company's Registration Statement on Form S-4, Registration No.
          33-71637).

  4.3     Memco Software Ltd. 1996 Stock Option and Incentive Plan (incorporated
          by reference to Memco's Registration Statement on Form S-8,
          Registration No. 333-6060).

  4.4     Memco Software Ltd. 1996 Stock Option and Incentive Plan (II)
          (incorporated by reference to Memco's Registration Statement on Form 
          S-8, Registration No. 333-6060).

  4.5     Memco Software Ltd. 1997 Stock Option and Incentive Plan (III)
          (incorporated by reference to Memco's Registration Statement on Form 
          S-8, Registration No. 333-8478).

  4.6     Memco Software Ltd. 1998 Stock Option and Incentive Plan (IV).*

  4.7     Network Information Technology Inc. 1993 Stock Option Plan
          (incorporated by reference to Memco's Registration Statement on Form 
          S-8, Registration No. 333-8854).

  4.8     Network Information Technology, Inc. 1997 Equity Incentive Plan
          (incorporated by reference to Memco's Registration Statement on Form 
          S-8, Registration No. 333-8854).

  4.9     Form of Stock Option Agreement for the Memco Software Ltd. 1997 Stock
          Option and Incentive Plan (III).*

  4.10    Form of Stock Option Agreement for the Memco Software Ltd. 1998 Stock
          Option and Incentive Plan (IV).*

  4.11    Rights Agreement dated as of December 21, 1995, between the Company
          and Harris Trust and Savings Bank (incorporated by reference to
          Exhibit 1 to the Company's Registration Statement on Form 8-A, filed
          December 26, 1995).

  5       Opinion of counsel as to legality of shares of Common Stock being
          offered (including consent).*

  15      Acknowledgement of Certified Public Accountants Regarding Independent
          Auditor's Review Report.*

  23.1    Consent of KPMG LLP.*

  23.2    Consent of Ernst & Young LLP.*

  23.3    Consent of Arthur Andersen LLP.*

  23.4    Consent of Katten Muchin & Zavis (included in their opinion filed as
          Exhibit 5 herein).

  24      Power of Attorney (included on the signature page of this Registration
          Statement).
 ---------
* Filed herewith.
                                       6