<PAGE>   1
      As filed with the Securities and Exchange Commission on July 19, 1999
                                                 Registration No. 333-
================================================================================

                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

                                   ----------

                                    FORM S-8
                          REGISTRATION STATEMENT UNDER
                           THE SECURITIES ACT OF 1933

                                   ----------

                                 GENENTECH, INC.
             (Exact name of registrant as specified in its charter)

           Delaware                                      94-2345624
   (State of Incorporation)                  (I.R.S. Employer Identification No.




                                    1 DNA Way
                              South San Francisco,               94080-4990
                                   California                    (Zip Code)
                              (Address of principal
                               executive offices)


                                   ----------

                     1990 Stock Option/Stock Incentive Plan
                             1994 Stock Option Plan
                     1996 Stock Option/Stock Incentive Plan
                            (Full title of the plans)


                           Stephen G. Juelsgaard, Esq.
              Senior Vice President, General Counsel and Secretary
                                 Genentech, Inc.
                                    1 DNA Way
                   South San Francisco, California 94080-4990
                     (Name and address of agent for service)



                                 (650) 225-1000
          (Telephone number, including area code, of agent for service)


                         CALCULATION OF REGISTRATION FEE

<TABLE>
<CAPTION>
=============================================================================================================
                                               Proposed Maximum      Proposed Maximum
 Title of Securities        Amount to be           Offering             Aggregate             Amount of
   to be Registered          Registered       Price per Share (1)   Offering Price (1)    Registration Fee
-------------------------------------------------------------------------------------------------------------
<S>                     <C>                   <C>                  <C>                   <C>
Common stock, par value   3,991,263 shares          $57.38             $229,018,671          $63,667.19
   $.02 per share
=============================================================================================================
</TABLE>

(1)     The Proposed Maximum Offering Price Per Share was estimated pursuant to
        Rule 457(h) promulgated under the Securities Act of 1933, as amended.
        Pursuant to Rule 457(h), the per share price of options to purchase
        stock under an employee stock option plan may be estimated by reference
        to the price to be paid upon exercise of such options. All options
        covering the 3,991,263 shares of Genentech, Inc.'s common stock to be
        registered hereunder are outstanding, and the weighted average exercise
        price of such options is $57.38. The actual exercise price of each
        option was determined with reference to the grant date of that option.
<PAGE>   2

PART II:  INFORMATION REQUIRED IN THE REGISTRATION STATEMENT

ITEM 3:  INCORPORATION OF DOCUMENTS BY REFERENCE

        In this Registration Statement, "Genentech," "we," "us" and "our" refer
to Genentech, Inc. The Securities and Exchange Commission, or SEC, allows us to
"incorporate by reference" the information we file with it, which means we can
disclose important information by referring to those documents. The information
included in the following documents is incorporated by reference and is
considered to be a part of this Registration Statement. The most recent
information that we file with the SEC automatically updates and supersedes more
dated information. We have previously filed the following documents with the SEC
and incorporate them by reference into this Registration Statement:

        (a) Our annual report on Form 10-K for the year ended December 31, 1998;

        (b) Our quarterly report on Form 10-Q for the quarter ended March 31,
1999;

        (c) Our current report on Form 8-K dated June 28, 1999; and

        (d) The description under the heading "Description of Capital Stock"
relating to our common stock in the prospectus included in our Amendment No. 3
to the Registration Statement on Form S-3 (Registration No. 333-80601) filed
with the SEC on July 16, 1999, and the description under the heading
"Description of Capital Stock" relating to the common stock in the our final
prospectus filed with the SEC pursuant to Rule 424(b) under the Securities Act
of 1933, as amended, which is commonly known as the Securities Act, including
any amendment or report filed for the purpose of updating that description.

        We also incorporate by reference all documents subsequently filed by us
pursuant to Section 13(a), 13(c), 14 or 15(d) of the Securities Exchange Act of
1934, as amended, which is commonly known as the Exchange Act, until all of the
shares registered under this Registration Statement are sold.

        We will provide without charge to each person to whom a prospectus is
delivered, including any beneficial owner, a copy of any or all of the
information that has been incorporated by reference in this Registration
Statement. If you would like to obtain this information from us, please direct
your request to the Investor Relations Department, either in writing or by
telephone, to Genentech, Inc., 1 DNA Way, South San Francisco, California 94080,
Attention Investor Relations (650) 225-1260.


ITEM 4: DESCRIPTION OF SECURITIES

         We have incorporated by reference the description under the heading
"Description of Capital Stock" relating to our common stock in the prospectus
included in our Amendment No. 3 to the Registration Statement on Form S-3
(Registration No. 333-80601) filed with the SEC on July 16, 1999, and the
description under the heading "Description of Capital Stock" relating to the
common stock in the our final prospectus filed with the SEC pursuant to Rule
424(b) under the Securities Act, including any amendment or report filed for the
purpose of updating that description.


ITEM 5: INTERESTS OF NAMED EXPERTS AND COUNSEL

        Stephen G. Juelsgaard, Senior Vice President, General Counsel and
Secretary of Genentech, is an officer of Genentech and has received options
under our 1994 Stock Option Plan and our 1996 Stock Option/Stock Incentive Plan.


ITEM 6: INDEMNIFICATION OF DIRECTORS AND OFFICERS

        Our certificate of incorporation limits, to the fullest extent permitted
by Delaware corporate law, the personal liability of directors for monetary
damages for breach of their fiduciary duties.


<PAGE>   3

        Section 145 of the General Corporation Law of the State of Delaware (the
"DGCL") provides, in summary, that directors and officers of Delaware
corporations are entitled, under certain circumstances, to be indemnified
against all expenses and liabilities (including attorneys' fees) incurred by
them as a result of suits brought against them in their capacity as a director
or officer, if they acted in good faith and in a manner they reasonably believed
to be in or not opposed to the best interests of the corporation, and with
respect to any criminal action or proceeding, if they had no reasonable cause to
believe their conduct was unlawful; provided, that no indemnification may be
made against expenses in respect of any claim, issue or matter as to which they
shall have been adjudged to be liable to the corporation, unless and only to the
extent that the court in which such action or suit was brought shall determine
upon application that, despite the adjudication of liability but in view of all
the circumstances of the case, they are fairly and reasonably entitled to
indemnity for such expenses which the court shall deem proper. Any such
indemnification may be made by the corporation only as authorized in each
specific case upon a determination by the stockholders or disinterested
directors that indemnification is proper because the indemnitee has met the
applicable standard of conduct.

        Our board of directors may provide similar indemnification to our
officers, employees and agents as it deems appropriate and as authorized by
Delaware law. We may purchase insurance on behalf of any director, officer,
employee or agent against any expense incurred by such person in his or her
capacity.

        Our certificate of incorporation also provides that Roche Holdings,
Inc., or Roche, which is our majority stockholder, and the officers or directors
of Roche will not be presumed liable to us or our stockholders for breach of any
fiduciary duty or duty of loyalty, failure to act in the best interests of
Genentech, or receipt of any improper personal benefit, simply because Roche or
any director or officer of Roche, in good faith, takes any action, exercises any
right or gives or withholds any consent with respect to any agreement or
contract between Roche and Genentech.

        In addition, Roche will not be liable to us or our stockholders for
breach of any fiduciary duty if Roche pursues or acquires a potential corporate
opportunity of ours or does not inform us of a potential corporate opportunity.
If a director, officer or employee of Genentech who is also a director, officer
or employee of Roche knows of a potential transaction or matter that may be a
corporate opportunity both for Genentech and Roche, the director, officer or
employee is entitled to offer the corporate opportunity to us or Roche as the
director, officer or employee deems appropriate under the circumstances in his
or her sole discretion, and no such director, officer or employee will be liable
to us or our stockholders for breach of any fiduciary duty or duty of loyalty or
failure to act in our best interests or the derivation of any improper personal
benefit by reason of the fact that such director, officer or employee offered
such corporate opportunity to Roche (rather than to us) or did not communicate
information regarding such corporate opportunity to us, or Roche pursues or
acquires such corporate opportunity for itself or directs such corporate
opportunity to another person or does not communicate the corporate opportunity
to us.

        Neither Roche nor any officer or director thereof shall be liable to us
or our stockholders for breach of any fiduciary duty or duty of loyalty or
failure to act in (or not opposed to) our best interests or the derivation of
any improper personal benefit by reason of the fact that Roche or an officer of
director thereof in good faith takes any action or exercises any rights or gives
or withholds any consent in connection with any agreement or contract between
Roche and Genentech. No vote cast or other action taken by any person who is an
officer, director or other representative of Roche, which vote is cast or action
is taken by such person in his capacity as a director of Genentech, shall
constitute an action of or the exercise of a right by or a consent of Roche for
the purpose of any such agreement or contract.


ITEM 7: EXEMPTION FROM REGISTRATION CLAIMED

        Not applicable.


<PAGE>   4

ITEM 8: EXHIBITS

<TABLE>
<CAPTION>
EXHIBIT
NUMBER
<S>          <C>
    5        Opinion of Stephen G. Juelsgaard, Esq.

   15.1      Letter re: Unaudited Interim Financial Information.

   23.1      Consent of Ernst & Young LLP, independent auditors.

   23.2      Consent of Stephen G. Juelsgaard, Esq. is contained in Exhibit 5 to
             this Registration Statement.

   24        Power of Attorney is contained on the signature pages.

   99.1      1990 Stock Option/Stock Incentive Plan.

   99.2      1994 Stock Option Plan.

   99.3      1996 Stock Option/Stock Incentive Plan.

   99.4      Resolutions of the Executive Committee of the Board of Directors of
             Genentech, Inc. Relating to Employee Compensation, pursuant to an
             Action by Unanimous Written Consent of the Executive Committee of
             the Board of Directors of Genentech, Inc., to which such Resolutions
             are attached as "Exhibit B."
</TABLE>


ITEM 9: UNDERTAKINGS

1.      The undersigned registrant 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, as amended, which is commonly
                       known as the Securities Act;

               (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% 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


<PAGE>   5

               by the issuer pursuant to section 13 or section 15(d) of the
               Exchange Act that are incorporated by reference herein.

        (b)    That, for the purpose of determining any liability under the
               Securities Act, each such post-effective amendment shall be
               deemed to be a new registration statement relating to the
               securities offered herein, 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 undersigned registrant hereby undertakes that, for purposes of
        determining any liability under the Securities Act, each filing of the
        registrant's annual report pursuant to Section 13(a) or Section 15(d) of
        the Exchange Act (and, where applicable, each filing of an employee
        benefit plan's annual report pursuant to 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 herein, 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 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 Securities 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
        Securities Act and will be governed by the final adjudication of such
        issue.

<PAGE>   6

                                   SIGNATURES

        Pursuant to the requirements of the Securities Act of 1933, as amended,
the undersigned registrant 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 South San Francisco, State of
California, on July 19, 1999.


                                        GENENTECH, INC.


                                        By:       /s/ Stephen G. Juelsgaard
                                               ---------------------------------
                                        Name:  Stephen G. Juelsgaard
                                        Title: Senior Vice President, General
                                               Counsel and Secretary

<PAGE>   7

                                POWER OF ATTORNEY

        KNOW ALL PERSONS BY THESE PRESENTS, that each person whose signature
appears below constitutes and appoints Arthur D. Levinson and Stephen G.
Juelsgaard, and each or any one of them, his true and lawful attorney-in-fact
and agent, 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 attorneys-in-fact and agents, and each of them, full power and authority to
do and perform each and every act and thing requisite and necessary to be done
in connection therewith, as fully to all intents and purposes as he might or
could do in person, hereby ratifying and confirming all that said
attorneys-in-fact and agents, or any of them, or their or his substitutes or
substitute, may lawfully do or cause to be done by virtue hereof.

        Pursuant to the requirements of the Securities Act of 1933, this
Registration Statement has been signed by the following persons in the
capacities and on the dates indicated.


<TABLE>
<CAPTION>
                 SIGNATURE                                   TITLE                             DATE
<S>                                            <C>                                        <C>

       /s/ ARTHUR D. LEVINSON                  Principal Executive Officer and            July 19, 1999
------------------------------------           Director
         Arthur D. Levinson

      /s/ LOUIS J. LAVIGNE, JR.                Principal Financial Officer                July 19, 1999
------------------------------------
        Louis J. Lavigne, Jr.

         /s/ JOHN M. WHITING                   Principal Accounting Officer               July 19, 1999
------------------------------------
           John M. Whiting

         /s/ FRANZ B. HUMER                    Director                                   July 19, 1999
------------------------------------
           Franz B. Humer

      /s/ JONATHAN K.C. KNOWLES                Director                                   July 19, 1999
------------------------------------
        Jonathan K.C. Knowles
</TABLE>

<PAGE>   8

                                  EXHIBIT INDEX


<TABLE>
<CAPTION>
  EXHIBIT                                                                        SEQUENTIAL
  NUMBER                               DESCRIPTION                              PAGE NUMBERS
<S>        <C>                                                                  <C>

    5      Opinion of Stephen G. Juelsgaard, Esq.

   15.1    Letter re: Unaudited Interim Financial Information.

   23.1    Consent of Ernst & Young LLP, independent auditors.

   23.2    Consent of Stephen G. Juelsgaard, Esq. is contained in Exhibit 5 to
           this Registration Statement.

   24      Power of Attorney is contained on the signature pages.

   99.1    1990 Stock Option/Stock Incentive Plan.

   99.2    1994 Stock Option Plan.

   99.3    1996 Stock Option/Stock Incentive Plan.

   99.4    Resolutions of the Executive Committee of the Board of Directors of
           Genentech, Inc. Relating to Employee Compensation, pursuant to an
           Action by Unanimous Written Consent of the Executive Committee of the
           Board of Directors of Genentech, Inc., to which such Resolutions are
           attached as "Exhibit B."
</TABLE>
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1
      As filed with the Securities and Exchange Commission on July 19, 1999
                                                 Registration No. 333-
================================================================================

                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

                                   ----------

                                    FORM S-8
                          REGISTRATION STATEMENT UNDER
                           THE SECURITIES ACT OF 1933

                                   ----------

                                 GENENTECH, INC.
             (Exact name of registrant as specified in its charter)

           Delaware                                      94-2345624
   (State of Incorporation)                  (I.R.S. Employer Identification No.

                                    1 DNA Way
                              South San Francisco,               94080-4990
                                   California                    (Zip Code)
                              (Address of principal
                               executive offices)

                                   ----------

                     1990 Stock Option/Stock Incentive Plan
                             1994 Stock Option Plan
                     1996 Stock Option/Stock Incentive Plan
                            (Full title of the plans)

                           Stephen G. Juelsgaard, Esq.
              Senior Vice President, General Counsel and Secretary
                                 Genentech, Inc.
                                    1 DNA Way
                   South San Francisco, California 94080-4990
                     (Name and address of agent for service)

                                 (650) 225-1000
          (Telephone number, including area code, of agent for service)

                         CALCULATION OF REGISTRATION FEE
=============================================================================================================
                                               Proposed Maximum      Proposed Maximum
 Title of Securities        Amount to be           Offering             Aggregate             Amount of
   to be Registered          Registered       Price per Share (1)   Offering Price (1)    Registration Fee
-------------------------------------------------------------------------------------------------------------
Common stock, par value   3,991,263 shares          $57.38             $229,018,671          $63,667.19
   $.02 per share
=============================================================================================================
(1)     The Proposed Maximum Offering Price Per Share was estimated pursuant to
        Rule 457(h) promulgated under the Securities Act of 1933, as amended.
        Pursuant to Rule 457(h), the per share price of options to purchase
        stock under an employee stock option plan may be estimated by reference
        to the price to be paid upon exercise of such options. All options
        covering the 3,991,263 shares of Genentech, Inc.'s common stock to be
        registered hereunder are outstanding, and the weighted average exercise
        price of such options is $57.38. The actual exercise price of each
        option was determined with reference to the grant date of that option.
2

PART II:  INFORMATION REQUIRED IN THE REGISTRATION STATEMENT

ITEM 3:  INCORPORATION OF DOCUMENTS BY REFERENCE

        In this Registration Statement, "Genentech," "we," "us" and "our" refer
to Genentech, Inc. The Securities and Exchange Commission, or SEC, allows us to
"incorporate by reference" the information we file with it, which means we can
disclose important information by referring to those documents. The information
included in the following documents is incorporated by reference and is
considered to be a part of this Registration Statement. The most recent
information that we file with the SEC automatically updates and supersedes more
dated information. We have previously filed the following documents with the SEC
and incorporate them by reference into this Registration Statement:

        (a) Our annual report on Form 10-K for the year ended December 31, 1998;

        (b) Our quarterly report on Form 10-Q for the quarter ended March 31,
1999;

        (c) Our current report on Form 8-K dated June 28, 1999; and

        (d) The description under the heading "Description of Capital Stock"
relating to our common stock in the prospectus included in our Amendment No. 3
to the Registration Statement on Form S-3 (Registration No. 333-80601) filed
with the SEC on July 16, 1999, and the description under the heading
"Description of Capital Stock" relating to the common stock in the our final
prospectus filed with the SEC pursuant to Rule 424(b) under the Securities Act
of 1933, as amended, which is commonly known as the Securities Act, including
any amendment or report filed for the purpose of updating that description.

        We also incorporate by reference all documents subsequently filed by us
pursuant to Section 13(a), 13(c), 14 or 15(d) of the Securities Exchange Act of
1934, as amended, which is commonly known as the Exchange Act, until all of the
shares registered under this Registration Statement are sold.

        We will provide without charge to each person to whom a prospectus is
delivered, including any beneficial owner, a copy of any or all of the
information that has been incorporated by reference in this Registration
Statement. If you would like to obtain this information from us, please direct
your request to the Investor Relations Department, either in writing or by
telephone, to Genentech, Inc., 1 DNA Way, South San Francisco, California 94080,
Attention Investor Relations (650) 225-1260.

ITEM 4: DESCRIPTION OF SECURITIES

         We have incorporated by reference the description under the heading
"Description of Capital Stock" relating to our common stock in the prospectus
included in our Amendment No. 3 to the Registration Statement on Form S-3
(Registration No. 333-80601) filed with the SEC on July 16, 1999, and the
description under the heading "Description of Capital Stock" relating to the
common stock in the our final prospectus filed with the SEC pursuant to Rule
424(b) under the Securities Act, including any amendment or report filed for the
purpose of updating that description.

ITEM 5: INTERESTS OF NAMED EXPERTS AND COUNSEL

        Stephen G. Juelsgaard, Senior Vice President, General Counsel and
Secretary of Genentech, is an officer of Genentech and has received options
under our 1994 Stock Option Plan and our 1996 Stock Option/Stock Incentive Plan.

ITEM 6: INDEMNIFICATION OF DIRECTORS AND OFFICERS

        Our certificate of incorporation limits, to the fullest extent permitted
by Delaware corporate law, the personal liability of directors for monetary
damages for breach of their fiduciary duties.
3

        Section 145 of the General Corporation Law of the State of Delaware (the
"DGCL") provides, in summary, that directors and officers of Delaware
corporations are entitled, under certain circumstances, to be indemnified
against all expenses and liabilities (including attorneys' fees) incurred by
them as a result of suits brought against them in their capacity as a director
or officer, if they acted in good faith and in a manner they reasonably believed
to be in or not opposed to the best interests of the corporation, and with
respect to any criminal action or proceeding, if they had no reasonable cause to
believe their conduct was unlawful; provided, that no indemnification may be
made against expenses in respect of any claim, issue or matter as to which they
shall have been adjudged to be liable to the corporation, unless and only to the
extent that the court in which such action or suit was brought shall determine
upon application that, despite the adjudication of liability but in view of all
the circumstances of the case, they are fairly and reasonably entitled to
indemnity for such expenses which the court shall deem proper. Any such
indemnification may be made by the corporation only as authorized in each
specific case upon a determination by the stockholders or disinterested
directors that indemnification is proper because the indemnitee has met the
applicable standard of conduct.

        Our board of directors may provide similar indemnification to our
officers, employees and agents as it deems appropriate and as authorized by
Delaware law. We may purchase insurance on behalf of any director, officer,
employee or agent against any expense incurred by such person in his or her
capacity.

        Our certificate of incorporation also provides that Roche Holdings,
Inc., or Roche, which is our majority stockholder, and the officers or directors
of Roche will not be presumed liable to us or our stockholders for breach of any
fiduciary duty or duty of loyalty, failure to act in the best interests of
Genentech, or receipt of any improper personal benefit, simply because Roche or
any director or officer of Roche, in good faith, takes any action, exercises any
right or gives or withholds any consent with respect to any agreement or
contract between Roche and Genentech.

        In addition, Roche will not be liable to us or our stockholders for
breach of any fiduciary duty if Roche pursues or acquires a potential corporate
opportunity of ours or does not inform us of a potential corporate opportunity.
If a director, officer or employee of Genentech who is also a director, officer
or employee of Roche knows of a potential transaction or matter that may be a
corporate opportunity both for Genentech and Roche, the director, officer or
employee is entitled to offer the corporate opportunity to us or Roche as the
director, officer or employee deems appropriate under the circumstances in his
or her sole discretion, and no such director, officer or employee will be liable
to us or our stockholders for breach of any fiduciary duty or duty of loyalty or
failure to act in our best interests or the derivation of any improper personal
benefit by reason of the fact that such director, officer or employee offered
such corporate opportunity to Roche (rather than to us) or did not communicate
information regarding such corporate opportunity to us, or Roche pursues or
acquires such corporate opportunity for itself or directs such corporate
opportunity to another person or does not communicate the corporate opportunity
to us.

        Neither Roche nor any officer or director thereof shall be liable to us
or our stockholders for breach of any fiduciary duty or duty of loyalty or
failure to act in (or not opposed to) our best interests or the derivation of
any improper personal benefit by reason of the fact that Roche or an officer of
director thereof in good faith takes any action or exercises any rights or gives
or withholds any consent in connection with any agreement or contract between
Roche and Genentech. No vote cast or other action taken by any person who is an
officer, director or other representative of Roche, which vote is cast or action
is taken by such person in his capacity as a director of Genentech, shall
constitute an action of or the exercise of a right by or a consent of Roche for
the purpose of any such agreement or contract.

ITEM 7: EXEMPTION FROM REGISTRATION CLAIMED

        Not applicable.
4

ITEM 8: EXHIBITS
EXHIBIT
NUMBER
5        Opinion of Stephen G. Juelsgaard, Esq.

   15.1      Letter re: Unaudited Interim Financial Information.

   23.1      Consent of Ernst & Young LLP, independent auditors.

   23.2      Consent of Stephen G. Juelsgaard, Esq. is contained in Exhibit 5 to
             this Registration Statement.

   24        Power of Attorney is contained on the signature pages.

   99.1      1990 Stock Option/Stock Incentive Plan.

   99.2      1994 Stock Option Plan.

   99.3      1996 Stock Option/Stock Incentive Plan.

   99.4      Resolutions of the Executive Committee of the Board of Directors of
             Genentech, Inc. Relating to Employee Compensation, pursuant to an
             Action by Unanimous Written Consent of the Executive Committee of
             the Board of Directors of Genentech, Inc., to which such Resolutions
             are attached as "Exhibit B."
ITEM 9: UNDERTAKINGS

1.      The undersigned registrant 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, as amended, which is commonly
                       known as the Securities Act;

               (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% 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
5

               by the issuer pursuant to section 13 or section 15(d) of the
               Exchange Act that are incorporated by reference herein.

        (b)    That, for the purpose of determining any liability under the
               Securities Act, each such post-effective amendment shall be
               deemed to be a new registration statement relating to the
               securities offered herein, 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 undersigned registrant hereby undertakes that, for purposes of
        determining any liability under the Securities Act, each filing of the
        registrant's annual report pursuant to Section 13(a) or Section 15(d) of
        the Exchange Act (and, where applicable, each filing of an employee
        benefit plan's annual report pursuant to 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 herein, 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 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 Securities 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
        Securities Act and will be governed by the final adjudication of such
        issue.
6

                                   SIGNATURES

        Pursuant to the requirements of the Securities Act of 1933, as amended,
the undersigned registrant 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 South San Francisco, State of
California, on July 19, 1999.

                                        GENENTECH, INC.

                                        By:       /s/ Stephen G. Juelsgaard
                                               ---------------------------------
                                        Name:  Stephen G. Juelsgaard
                                        Title: Senior Vice President, General
                                               Counsel and Secretary
7

                                POWER OF ATTORNEY

        KNOW ALL PERSONS BY THESE PRESENTS, that each person whose signature
appears below constitutes and appoints Arthur D. Levinson and Stephen G.
Juelsgaard, and each or any one of them, his true and lawful attorney-in-fact
and agent, 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 attorneys-in-fact and agents, and each of them, full power and authority to
do and perform each and every act and thing requisite and necessary to be done
in connection therewith, as fully to all intents and purposes as he might or
could do in person, hereby ratifying and confirming all that said
attorneys-in-fact and agents, or any of them, or their or his substitutes or
substitute, may lawfully do or cause to be done by virtue hereof.

        Pursuant to the requirements of the Securities Act of 1933, this
Registration Statement has been signed by the following persons in the
capacities and on the dates indicated.
SIGNATURE                                   TITLE                             DATE
/s/ ARTHUR D. LEVINSON                  Principal Executive Officer and            July 19, 1999
------------------------------------           Director
         Arthur D. Levinson

      /s/ LOUIS J. LAVIGNE, JR.                Principal Financial Officer                July 19, 1999
------------------------------------
        Louis J. Lavigne, Jr.

         /s/ JOHN M. WHITING                   Principal Accounting Officer               July 19, 1999
------------------------------------
           John M. Whiting

         /s/ FRANZ B. HUMER                    Director                                   July 19, 1999
------------------------------------
           Franz B. Humer

      /s/ JONATHAN K.C. KNOWLES                Director                                   July 19, 1999
------------------------------------
        Jonathan K.C. Knowles
8

                                  EXHIBIT INDEX
EXHIBIT                                                                        SEQUENTIAL
  NUMBER                               DESCRIPTION                              PAGE NUMBERS
5      Opinion of Stephen G. Juelsgaard, Esq.

   15.1    Letter re: Unaudited Interim Financial Information.

   23.1    Consent of Ernst & Young LLP, independent auditors.

   23.2    Consent of Stephen G. Juelsgaard, Esq. is contained in Exhibit 5 to
           this Registration Statement.

   24      Power of Attorney is contained on the signature pages.

   99.1    1990 Stock Option/Stock Incentive Plan.

   99.2    1994 Stock Option Plan.

   99.3    1996 Stock Option/Stock Incentive Plan.

   99.4    Resolutions of the Executive Committee of the Board of Directors of
           Genentech, Inc. Relating to Employee Compensation, pursuant to an
           Action by Unanimous Written Consent of the Executive Committee of the
           Board of Directors of Genentech, Inc., to which such Resolutions are
           attached as "Exhibit B."