Exhibit 4.1

                              ROCHE HOLDINGS, INC.
                            (a Delaware corporation)

                  $1,506,342,000 Principal Amount at Maturity
                     Liquid Yield Option(TM) Notes due 2015
                                 (Zero Coupon)

                      PRIVATE PLACEMENT PURCHASE AGREEMENT


                                                           January 12, 2000

MERRILL LYNCH & CO.
Merrill Lynch, Pierce, Fenner & Smith
Incorporated
World Financial Center
North Tower
New York, New York  10281

Ladies and Gentlemen:

     Roche Holdings, Inc., a Delaware corporation (the "Company"), confirms its
agreement with Merrill Lynch & Co., Merrill Lynch, Pierce Fenner & Smith
Incorporated (the "Underwriter") with respect to the issue and sale by the
Company and the purchase by the Underwriter of $1,506,342,000 aggregate
principal amount at maturity of the Company's Liquid Yield Option(TM) Notes due
2015 (the "Securities"). The Securities are to be issued pursuant to an
indenture to be dated as of the Closing Date (as hereinafter defined) (the
"Indenture") between the Company and The Bank of New York, as trustee (the
"Trustee"). In entering into this Agreement, the Underwriter is relying on the
representations, warranties, covenants and agreements of Genentech, Inc., a
Delaware corporation and, as of the date hereof, majority-owned subsidiary of
the Company ("Genentech"), made pursuant to an agreement with the Underwriter
dated the date hereof (the "Genentech Agreement") and executed concurrently
herewith.

     The Securities will be exchangeable at the option of the holders thereof,
at any time prior to maturity, unless previously redeemed or otherwise
purchased, for shares of common stock, par value $0.02 per share, of Genentech
("Genentech Common Stock"), in accordance with the terms and subject to the
conditions set forth in the Indenture and the Securities, initially at the
exchange rate specified in Schedule A hereto. The foregoing is subject to the
right of the Company, in accordance with the terms and subject to the
conditions set forth in the Indenture and the Securities, to pay cash equal to
market value of the Genentech Common Stock in lieu of delivering shares of
Genentech Common Stock.

     The holders from time-to-time of Securities will be entitled to the
benefits of a Registration Rights Agreement, substantially in the form attached
hereto as Exhibit A, with such changes as shall be agreed to by the parties
thereto (the "Registration Rights Agreement"), pursuant to which Genentech,
pursuant to the Registration Rights Agreement upon the execution thereof, will
use reasonable efforts to file a registration statement with the Securities and
Exchange Commission (the "Commission") registering resales of the shares of
Genentech Common Stock issuable upon exchange of the Securities, as referred to
in the Registration Rights Agreement, under the United States Securities Act of
1933, as amended (the "Securities Act").

     The Securities will be offered and sold to the Underwriter without being
registered under the Securities Act, in reliance upon exemptions therefrom. The
Company has prepared and delivered to the Underwriter a preliminary offering
memorandum dated January 11, 2000 (together with all documents incorporated by
reference therein, the "Preliminary Offering Memorandum") and has prepared and
will deliver to the Underwriter on the date hereof or as soon as practicable
thereafter, copies of a final offering memorandum dated January 12, 2000
(together with all amendments and supplements thereto, and together with all
documents incorporated by reference therein, the "Final Offering Memorandum"),
relating in part to the Securities. The Preliminary Offering Memorandum and the
Final Offering Memorandum are sometimes collectively referred to herein as the
"Offering Memorandum." The Offering Memorandum


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(as amended or supplemented if the Company shall have furnished any amendment
or supplement, and including the documents incorporated by reference therein),
the 1998 Annual Report of The Roche Group, and the unaudited Interim Report of
The Roche Group for the six months ended June 30, 1999, are hereinafter
referred to, both individually and collectively, as the "Disclosure Documents."
As used herein, the term "Genentech Disclosure" shall mean, collectively, (A)
(i) Genentech's registration statement on Form S-3 (Reg. No. 333-88651) filed
with the Commission, as amended at the time it became effective under the
Securities Act, and including the information deemed to be a part thereof as of
the time of effectiveness pursuant to paragraph (b) of Rule 430A under the
Securities Act (the "Registration Statement"), (ii) Genentech's Annual Report
on Form 10-K for the year ended December 31, 1998, (iii) Genentech's Quarterly
Reports on Form 10-Q for the quarters ended March 31, 1999, June 30, 1999 and
September 30, 1999, (iv) Genentech's Current Reports on Form 8-K dated June 2,
1999, June 22, 1999 and November 2, 1999, and (v) all documents filed by
Genentech with the Commission pursuant to Section 13(a), 13(c), 14 or 15 of the
Securities Exchange Act of 1934, as amended (the "Exchange Act"), subsequent to
the date hereof and until all of the Securities have been sold, each of which
documents in clauses (A)(i) through (v) is or will be, as the case may be,
incorporated by reference in the Preliminary Offering Memorandum and the Final
Offering Memorandum (the "Genentech Incorporated Documents"), and (B) the
sections of the Offering Memorandum entitled "Summary -- Genentech, Inc.", "--
Relationship Between Genentech and Roche", "-- Genentech Summary Consolidated
Financial Information" and "-- Recent Developments -- Genentech".

     The Company understands that the Underwriter may resell the Securities to
entities it reasonably believes are qualified institutional buyers ("Qualified
Institutional Buyers"), as that term is defined in, and in reliance on, Rule
144A under the Securities Act ("Rule 144A"), and pursuant to offers and sales
that occur outside the United States, to persons other than U.S. persons,
within the meaning of, and in reliance on, Regulation S under the Securities
Act ("Regulation S").

     SECTION 1. Sale of the Securities. On the basis of the representations and
warranties of the Company contained herein and of Genentech contained in the
Genentech Agreement and subject to the terms and conditions set forth herein,
the Company hereby agrees to sell to the Underwriter, and the Underwriter
hereby agrees to purchase from the Company, at the purchase price per $1,000
principal amount at maturity set forth in Schedule A hereto, the Securities.

     SECTION 2.  Offering by Underwriter.

     (a) The Company confirms that, in connection with the offering of the
Securities, it has authorized the Underwriter to distribute copies of the
Offering Memorandum (i) to persons it reasonably believes to be Qualified
Institutional Buyers and (ii) outside the United States, to persons other than
U.S. persons (as defined in Regulation S) to whom it reasonably believes offers
and sales of the Securities may be made in reliance upon Regulation S.

     (b) The Underwriter covenants and agrees with the Company that it will
make an offering of the Securities purchased hereunder on the terms set forth
in the Final Offering Memorandum, as soon as practicable after the date of this
Agreement as in its judgment is advisable, only (i) to persons it reasonably
believes to be Qualified Institutional Buyers and (ii) outside the United
States, to persons other than U.S. persons (as defined in Regulation S) to whom
it reasonably believes offers and sales of the Securities may be made in
reliance upon Regulation S. The Underwriter will offer the Securities initially
at the initial offering price per $1,000 principal amount at maturity of
Securities set forth in Schedule A hereto.

     (c) The Underwriter undertakes (i) not to utilize selling agents or
sub-underwriters in connection with the performance of its obligations under
this Agreement and (ii) not to grant a selling or similar concession to any
party in connection with the sale of the Securities.

     SECTION 3. Purchase and Delivery.

     (a) Payment for the Securities shall be made by the Underwriter to the
Company in United States dollars at Closing Time by wire transfer of
immediately available funds to a bank account designated by the Company at
10:00 a.m., New York time, on January 19, 2000, with the closing to occur at
the offices of Davis Polk & Wardwell, 450 Lexington Avenue, New York, New York
10017, or at such other time and place as the Underwriter and the Company


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shall agree. The time and date of such payment are hereinafter referred to as
the "Closing Time" and "Closing Date," respectively. The Securities will be
delivered to the Underwriter at Closing Time.

     (b) The certificate evidencing the Securities to be purchased by the
Underwriter shall be in such denominations and registered in such names as the
Underwriter may request in writing to the Company at least two full business
days before Closing Date. The certificates evidencing the Securities shall be
made available in New York City for examination and packaging by the
Underwriter not later than 10:00 a.m., New York time, on the business day prior
to the Closing Date.

     SECTION 4.  Representations and Warranties of the Company.

     The Company represents and warrants to the Underwriter that as of the date
of this Agreement and on the Closing Date:

          (i) The Final Offering Memorandum does not contain an untrue
     statement of a material fact or omit to state a material fact necessary in
     order to make the statements therein, in the light of the circumstances
     under which they were made, not misleading; provided, however, that none
     of the representations and warranties in this subsection (i) shall apply
     to statements in or omissions from the Final Offering Memorandum made in
     reliance upon and in conformity with information furnished in writing by
     the Underwriter expressly for use in the Final Offering Memorandum;

          (ii) The consolidated financial statements of the Company and its
     consolidated subsidiaries included in the Final Offering Memorandum (the
     "Company Financial Statements") present fairly the consolidated financial
     position of the Company and its consolidated subsidiaries as at the dates
     indicated and the consolidated results of their operations for the periods
     specified, and have been prepared in accordance with generally accepted
     accounting principles applied on a consistent basis;

          (iii) The consolidated financial statements of Roche Holding Ltd, a
     company incorporated under the laws of Switzerland ("Roche"), and its
     consolidated subsidiaries included in the Final Offering Memorandum (the
     "Roche Financial Statements") present fairly the consolidated financial
     position of Roche and its consolidated subsidiaries as at the dates
     indicated and the consolidated results of their operations for the periods
     specified, and have been prepared in accordance with the accounting
     policies described in the Summary of Accounting Policies which accompany
     the Roche Financial Statements and were prepared in accordance with
     International Accounting Standards;

          (iv) Since the respective dates as of which information is given in
     the Final Offering Memorandum and except as otherwise stated or
     contemplated therein, (A) there has been no material adverse change or any
     development reasonably expected to result in a prospective material
     adverse change in the condition, financial or otherwise, or earnings of
     the Company and its subsidiaries considered as one enterprise, or of Roche
     and its subsidiaries considered a one enterprise; (B) there have been (i)
     no transactions entered into by the Company or any of its subsidiaries,
     other than those in the ordinary course of business, which are material
     with respect to the Company and its subsidiaries considered as one
     enterprise, and (ii) no transactions entered into by Roche or any of its
     subsidiaries, other than those in the ordinary course of business, which
     are material with respect to Roche and its subsidiaries considered as one
     enterprise; and (C) except for regularly scheduled dividends on any class
     of its capital stock, there has been no dividend or distribution of any
     kind declared, paid or made by or on behalf of the Company on any class of
     its capital stock;

          (v) The accountants who certified the Company Financial Statements
     are, with respect to the Company and its subsidiaries, independent public
     accountants;

          (vi) The accountants who certified the Roche Financial Statements
     are, with respect to Roche and its subsidiaries, independent public
     accountants;

          (vii) Each of F. Hoffmann-La Roche Ltd. and Hoffmann-La Roche Inc.
     (collectively, the "Subsidiaries") has been duly incorporated and is
     validly existing as a corporation in good standing under the laws of its
     jurisdiction


<PAGE>


     of incorporation, with corporate power and authority to own its properties
     and conduct its business as described in the Final Offering Memorandum or
     as otherwise currently conducted; and each Subsidiary is duly qualified as
     a foreign corporation to transact business and is in good standing in each
     jurisdiction in which such qualification is required, whether by reason of
     the ownership or leasing of property or the conduct of business, except
     where the failure to be so qualified would not have a material adverse
     effect on the condition, financial or otherwise, or earnings of the
     Company and its subsidiaries considered as one enterprise or of Roche and
     its subsidiaries considered as one enterprise;

          (viii) The Company has been duly incorporated and is validly existing
     as a corporation in good standing under the laws of the State of Delaware,
     with corporate power and authority to own its properties and conduct its
     business as contemplated in the Final Offering Memorandum; and the Company
     is duly qualified as a foreign corporation to transact business and is in
     good standing in each jurisdiction in which such qualification is
     required, whether by reason of the ownership or leasing of property or the
     conduct of business, except where the failure to be so qualified would not
     have a material adverse effect on the condition, financial or otherwise,
     or earnings of the Company and its subsidiaries considered as one
     enterprise or of Roche and its subsidiaries considered as one enterprise;

          (ix) Except as indicated in the Final Offering Memorandum, Roche owns
     directly or indirectly all of the issued and outstanding shares of capital
     stock of the Company and each of the Subsidiaries free and clear of any
     material security interest, mortgage, pledge, lien or encumbrance;

          (x) The Securities have been duly and validly authorized for issuance
     and sale to the Underwriter pursuant to this Agreement and, when executed,
     authenticated and delivered in the manner provided for in the Indenture
     against payment of the consideration therefor in accordance with this
     Agreement, will be duly issued and will constitute valid and legally
     binding obligations of the Company enforceable against the Company in
     accordance with their terms (except as enforcement thereof may be limited
     by bankruptcy, insolvency or other laws relating to or affecting
     enforcement of creditors' rights or by general equity principles) and will
     be entitled to the benefits of the Indenture and the Registration Rights
     Agreement; the forms of the certificate to be used to evidence the
     Securities will be in the form contemplated by the Indenture; and, at the
     Closing Time, the Company will have an authorized and outstanding
     capitalization as set forth in the Final Offering Memorandum;

          (xi) The Company has all necessary corporate power and authority to
     enter into and to perform its obligations under the Indenture and to
     consummate the transactions contemplated thereby; the Indenture has been
     duly and validly authorized by the Company and, when executed and
     delivered by the Company and authorized, executed and delivered by the
     Trustee, will constitute a valid and legally binding obligation of the
     Company enforceable against the Company in accordance with its terms,
     except as enforcement thereof may be limited by bankruptcy, insolvency or
     other laws relating to or affecting enforcement of creditors' rights or by
     general equity principles; and the Indenture is not required to be
     qualified under the Trust Indenture Act of 1939, as amended;

          (xii) The Securities and the Indenture conform in all material
     respects to the statements relating thereto contained in the Final
     Offering Memorandum;

          (xiii) If and when the shares of Genentech Common Stock are delivered
     to holders of the Securities upon exchange of the Securities as provided
     in the Indenture, they will be free and clear of any security interest,
     mortgage, pledge, lien, encumbrance, claim or equity;

          (xiv) The execution and delivery by the Company of, and the
     performance by the Company of its obligations under, this Agreement, the
     Indenture and the Securities, the issuance and sale of the Securities
     hereunder, the delivery of the Genentech Common Stock upon exchange of the
     Securities as provided in the Indenture, and the consummation by the
     Company of the other transactions herein and therein contemplated will not
     (i) conflict with or result in a breach of any existing provisions of the
     laws or regulations of the United States of America, the State of New
     York, the State of Delaware or Switzerland or of the terms of the
     constitutive documents of the Company or of any other material
     restriction, whether statutory or otherwise, or of any material order,
     judgment or decree to which it is a party or (ii) materially conflict with
     or result in a material breach of any material agreement or other material
     instrument, whether contractual or otherwise, to which the Company is
     bound;


<PAGE>


          (xv) Roche has been advised by the Commission that it has been added
     to the list of foreign private issuers that claim exemption from the
     registration requirements of Section 12(g) of the United States Securities
     Exchange Act of 1934, as amended (the "Exchange Act");

          (xvi) There are no approvals, authorizations, consents, orders,
     registrations or qualifications from or with any court of governmental
     agency or body required for the sale to the Underwriter of the Securities,
     for the execution of this Agreement, the Indenture or the Registration
     Rights Agreement or, as of the date hereof and as of the Closing Date, for
     the delivery of the Genentech Common Stock upon exchange of the Securities
     as provided in the Indenture (except such as may be required under the
     state securities or "blue sky" laws of any jurisdiction);

          (xvii) There is no stamp, documentary, registration or similar duty
     or tax payable in connection with the issuance, sale or delivery of the
     Securities to the Underwriter;

          (xviii) To the best knowledge of the Company, neither the Company,
     Roche nor any Subsidiary is in default in the performance of any agreement
     contained in any material contract, indenture, mortgage, loan agreement,
     lease or other document or instrument to which the Company, Roche or any
     Subsidiary is a party or by which any of them may be bound, or to which
     any of their property may be subject, other than defaults that would not,
     in the opinion of the Company, singly or in the aggregate, result in a
     material adverse change in the condition, financial or otherwise, or
     earnings of the Company and its subsidiaries considered as one enterprise
     or of Roche and its subsidiaries considered as one enterprise;

          (xix) To the best knowledge of the Company, and except as disclosed
     in the Final Offering Memorandum, the Company, Roche and the Subsidiaries
     have obtained all governmental approvals and authorizations necessary to
     carry on their respective businesses as presently conducted, except where
     the failure to obtain any such approvals or authorizations would not
     result in a material adverse change in the condition, financial or
     otherwise, or earnings of the Company and its subsidiaries considered as
     one enterprise or of Roche and its subsidiaries considered as one
     enterprise;

          (xx) Except as disclosed in the Final Offering Memorandum, there is
     no action, suit, or proceeding pending or, to the knowledge of the
     Company, threatened, to which the Company, Roche or any of the
     Subsidiaries is a party or, to the knowledge of the Company, affecting the
     Company, Roche or any of the Subsidiaries, before or by any court or
     governmental agency or body, domestic or foreign, other than proceedings,
     suits or actions that would not, in the opinion of the Company, singly or
     in the aggregate, result in a material adverse change in the condition,
     financial or otherwise, or earnings of the Company and its subsidiaries
     considered as one enterprise or of Roche and its subsidiaries considered
     as one enterprise;

          (xxi) The Company, Roche and the Subsidiaries own or possess, or can
     acquire on reasonable terms, the patents, patent rights, licenses, and
     trade secrets which are material to the business now operated by them and
     described in the Final Offering Memorandum, and, except as disclosed in
     the Final Offering Memorandum, neither the Company, Roche nor any of the
     Subsidiaries has received any notice of infringement of or conflict with
     asserted rights of others with respect to any of the foregoing which might
     reasonably be expected in the opinion of the Company, singly or in the
     aggregate, to result in any material adverse change in the condition,
     financial or otherwise, or earnings of the Company and its subsidiaries
     considered as one enterprise or of Roche and its subsidiaries considered
     as one enterprise;

          (xxii) This Agreement has been duly authorized, executed and
     delivered by the Company and constitutes the valid and legally binding
     obligation of the Company enforceable against the Company in accordance
     with its terms, except as enforcement thereof may be limited by
     bankruptcy, insolvency or other laws relating to or affecting enforcement
     of creditors' rights or by general equity principles and except as rights
     to indemnity and contribution may be limited by applicable law; and

          (xxiii) The Keep Well Agreement, to be dated as of January 19, 2000
     (the "Keep Well Agreement") between the Company and Roche, has been duly
     authorized by the Company and Roche and, when duly executed and delivered,
     will constitute a valid and legally binding obligation of Roche
     enforceable against it in accordance with its terms, except as enforcement
     thereof may be limited by bankruptcy, insolvency or other laws relating to
     or


<PAGE>


     affecting enforcement of creditors' rights or by general equity
     principles, and will conform to the description thereof contained in the
     Final Offering Memorandum.

     SECTION 5.  Covenants of the Company.

     The Company covenants with the Underwriter as follows:

     (a) The Company will deliver to the Underwriter during the Company Period
(as defined below) such number of copies of the Final Offering Memorandum as
the Underwriter may reasonably require.

     (b) If, during the period beginning on the date of the Final Offering
Memorandum and ending on the date of completion of the offering of the
Securities, as determined by the Underwriter (and as notified in accordance
with Section 11(c) hereof), any event known to the Company relating to or
affecting the Company, Roche, Genentech or any of their respective subsidiaries
shall occur as a result of which it is necessary to amend or supplement the
Final Offering Memorandum in order to make the Final Offering Memorandum not
misleading in the light of the circumstances existing at the time it is
delivered to a purchaser, the Company will forthwith prepare and furnish to the
Underwriter the number of copies reasonably requested by the Underwriter of an
amendment or supplement to the Final Offering Memorandum which will amend or
supplement the Final Offering Memorandum so that as amended or supplemented it
will not contain any untrue statement of a material fact or omit to state a
material fact necessary in order to make the statements therein, in the light
of the circumstances existing at the time the Final Offering Memorandum is
delivered to a purchaser, not misleading. The costs and expenses of preparing
and furnishing to the Underwriter amendments or supplements during the period
beginning on the date of the Final Offering Memorandum and ending on the
earlier of (i) the date of completion of the offering of the Securities and
(ii) the date 60 days from the date hereof (the "Company Period") shall be
borne by the Company. The costs and expenses of preparing and furnishing to the
Underwriter any amendment or supplement after the expiration of the Company
Period shall be borne by the Underwriter.

     (c) The Company will use the net proceeds from the issuance and sale of
the Securities in the manner specified in the Final Offering Memorandum under
the caption "Use of Proceeds."

     (d) Neither the Company, Roche nor any of their respective affiliates (as
defined in Rule 405 under the Securities Act) will sell, offer for sale or
solicit offers to buy or otherwise negotiate in respect of any security (as
defined in the Securities Act) which will be integrated with the sale of the
Securities in a manner which would require the registration under the
Securities Act of the Securities.

     (e) Neither the Company, Roche, nor any of their respective affiliates
will offer or sell the Securities in the United States in any manner involving
a public offering within the meaning of Section 4(2) of the Securities Act or
by means of any form of general solicitation or general advertising (as those
terms are used in Regulation D under the Securities Act), including, but not
limited to, (i) any advertisement, article, notice or other communication
published in any newspaper, magazine or similar media or broadcast over
television or radio, or (ii) any seminar or meeting whose attendees have been
invited by any general solicitation or general advertising.

     (f) With respect to those Securities sold in reliance on Regulation S, (i)
none of the Company, Roche or any of their respective affiliates or any person
acting on its or their behalf (other than the Underwriter) has engaged or will
engage in any directed selling efforts (within the meaning of Regulation S) and
(ii) each of the Company, Roche and their respective affiliates and any person
acting on its or their behalf (other than the Underwriter) has complied and
will comply with the offering restrictions requirement of Regulation S.

     (g) The Company will notify the Underwriter promptly of any material
change or any condition which with the passage of time might reasonably be
expected to result in a material change affecting (i) any of the
representations, warranties, agreements and indemnities herein by the Company
or (ii) to its knowledge, any of the representations, warranties and agreements
of Genentech in the Genentech Agreement, prior to payment being made to the
Company at Closing Time.

     (h) For so long as any of the Securities are outstanding and are
"restricted securities" within the meaning of Rule 144(a)(3) under the
Securities Act, the Company will, if it is neither subject to the reporting
requirements of Section 13


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or 15(d) of the Exchange Act, nor exempt from such reporting requirements
pursuant to Rule 12g3-2(b) under the Exchange Act, provide to any holder of
Securities and any prospective purchaser of Securities designated by a holder
of such Securities, upon the request of such holder or prospective purchaser,
the information with respect to the Company required to be provided to such
holder or prospective purchaser by Rule 144A(d)(4) under the Securities Act.

     (i) In the event that certificated Securities are issued at any time prior
to one year after the Closing Date (other than in a transaction subject to Rule
144A), the Company shall as promptly as practicable put in place procedures
designed to prevent the registration of transfer of any Security not made in
accordance with the provisions of Regulation S, pursuant to registration under
the Securities Act or pursuant to an exemption from such registration.

     (j) The Company shall use all reasonable efforts to cause Genentech to
perform and observe all of Genentech's obligations under the Registration
Rights Agreement and to assist Genentech in connection with such obligations
(it being understood that the Company shall not, by reason of this clause (j),
be obligated to continue to own any shares of Genentech Common Stock).

     (k) The Company shall use all reasonable efforts to have the Securities
approved for listing on the Luxembourg Stock Exchange by the Closing Date or as
soon as practicable thereafter.

     SECTION 6. Payment of Expenses. Subject to the proviso at the end of this
paragraph, the Company shall pay the following expenses incident to the
performance of its obligations under this Agreement: (i) the printing of the
Offering Memorandum and of each amendment and supplement thereto to the extent
contemplated by Section 5(b) hereof; (ii) the preparation, issuance and
delivery to the Underwriter of the certificates for the Securities; (iii) the
fees and expenses associated with the designation of the Securities as
securities eligible for the Private Offerings, Resales and Trading through
Automated Linkages ("PORTAL") System; (iv) the fees and disbursements of
accountants for the Company, Roche, Genentech and their respective
subsidiaries; (v) the fees and disbursements of counsel for the Company, Roche
and Genentech; (vi) fees and expenses of the Trustee, including the fees and
disbursements of counsel for the Trustee in connection with the Indenture; and
(vii) subject to any subsequent agreement which may be reached between the
Company and the Underwriter, all reasonable out-of-pocket costs and expenses
incurred by the Underwriter and their affiliates in connection with the
offering of the Securities (including, without limitation, travel expenses
incurred by employees, representatives and agents of the Underwriter in
connection with the performance by them of the Underwriter's obligations
hereunder, but excluding the fees and disbursements of the Underwriter's
counsel); provided, however, that the Underwriter agrees to pay or, in the
event such expenses have already been paid by the Company, to reimburse the
Company for, all of the expenses described in this paragraph, as well as any
similar expenses incurred in connection with the preparation of the preliminary
offering memorandum dated October 11, 1999 relating to the then- planned
offering of Liquid Yield Option Notes and the agreements related to that
offering, up to an aggregate of $1,000,000.

     If this Agreement is canceled by the Underwriter in accordance with the
provisions of Section 7 or terminated by the Underwriter in accordance with the
provisions of Section 11(i), the Company shall reimburse the Underwriter and
its affiliates for all of their reasonable out-of-pocket expenses incurred
prior thereto or as may be required in connection with such termination,
including the fees and disbursements of counsel for the Underwriter, and such
cancellation shall have no effect on the obligation of the Company for certain
fees payable to the Underwriter and any affiliates of the Underwriter
previously or otherwise agreed upon in writing or the obligations of the
Company under Section 8.

     SECTION 7.  Conditions of Underwriters' Obligations.

     The obligations of the Underwriter under this Agreement to purchase the
Securities on the Closing Date will be subject to the accuracy of the
representations and warranties on the part of the Company herein, to the
accuracy of the representations and warranties of Genentech contained in the
Genentech Agreement, to the accuracy of the representations and warranties of
Roche contained in the Guarantee Agreement dated the date hereof (the
"Guarantee Agreement") between Roche and the Underwriter, to the performance
and observance by the Company of all covenants and agreements herein contained
on its part to be performed and observed, to the performance and observance by
Genentech of all of its covenants and agreements contained in the Genentech
Agreement, to the performance and observance by Roche of all of its covenants
and agreements contained in the Guarantee Agreement and to the following
conditions:


<PAGE>


     (a) At the Closing Time, the Underwriter shall have received the
following:

          (1) The opinion of Dr. Bruno Maier, Swiss counsel to the Company and
     Roche, substantially in the form set forth in Exhibit A to this Agreement;

          (2) The opinion of Davis Polk & Wardwell, United States counsel to
     the Company, Roche and Genentech, substantially in the form set forth in
     Exhibit B to this Agreement;

          (3) The opinion of Stephen G. Juelsgaard, Esq., Senior Vice President
     and General Counsel of Genentech, substantially in the form set forth in
     Exhibit A to the Genentech Agreement;

          (4) The opinion of Frederick C. Kentz III, Esq., counsel to
     Hoffman-La Roche Inc., substantially in the form set forth in Exhibit C to
     this Agreement; and

          (5) The opinion of Shearman & Sterling, counsel to the Underwriter,
     with respect to the applicability of the Securities Act to the offering
     and sale of the Securities and such other related matters as the
     Underwriter may reasonably require.

     (b) At the Closing Time, (i) there shall not have been, since the date as
of which information is given in the Final Offering Memorandum, and except as
otherwise stated or contemplated therein, any material adverse change or any
development reasonably expected to result in a prospective material adverse
change in the condition, financial or otherwise, or in the earnings or
operations of the Company and its subsidiaries considered as one enterprise or
of Roche and its subsidiaries considered as one enterprise or of Genentech and
its subsidiaries considered as one enterprise, (ii) no proceeding shall be
pending or, in the reasonable belief of the Underwriter (after consultation
with the Company), threatened to restrain or enjoin the delivery of the
Securities or the Genentech Common Stock as provided in the Indenture or to
revoke, repeal or rescind, in whole or in part, any laws, proceedings,
directives, resolutions, approvals, consents, deeds of issue or declarations
required for the actions contemplated under this Agreement, the Registration
Rights Agreement, the Indenture or the Securities, and (iii) the Underwriter
shall have received any certificate required pursuant to the Guarantee
Agreement; and the Underwriter shall have received (A) a certificate of an
executive officer of the Company on behalf of the Company, dated as of the
Closing Date, certifying as to (i) and (ii) above, to the effect that all the
other representations and warranties contained in Section 4 are true and
correct with the same force and effect as though expressly made at the Closing
Date, and to the effect that the Company shall have performed and observed all
of the covenants and agreements herein contained on its part to be performed
and observed on or prior to the Closing Date, and (B) a certificate of the
Chief Executive Officer and the Chief Financial Officer of Genentech certifying
that (i) the representations and warranties of Genentech contained in Section 2
of the Genentech Agreement are true and correct on and as of the Closing Date;
(ii) Genentech shall have complied with all of the covenants and agreements
contained in the Genentech Agreement on its part to be performed and observed
on or prior to the Closing Date; and (iii) there has not occurred any Material
Adverse Change (as defined in the Genentech Agreement) from that set forth or
contemplated in the Genentech Disclosure.

     (c) At the time of the execution of this Agreement, the Underwriter shall
have received from PricewaterhouseCoopers AG a letter or letters dated of even
date herewith, in the form previously agreed among the Underwriter,
PricewaterhouseCoopers AG and the Company, with respect to the financial
statements and other financial information of the Company and Roche included in
the Final Offering Memorandum.

     (d) At the Closing Time, the Underwriter shall have received from
PricewaterhouseCoopers AG a letter, dated as of such Closing Date, to the
effect that they reaffirm the statements made in the letter or letters
furnished pursuant to subsection (c) of this Section 7, except that any date
specified therein as of which certain procedures had been performed shall be a
date not more than five days prior to such Closing Date.

     (e) At the time of the execution of this Agreement, the Underwriter shall
have received from Ernst & Young LLP a letter or letters dated of even date
herewith, in the form previously agreed among the Underwriter and Ernst & Young
LLP, with respect to the financial statements and other financial information
of Genentech included or incorporated by reference in the Final Offering
Memorandum.


<PAGE>


     (f) At the Closing Date, the Underwriter shall have received from Ernst &
Young LLP a letter, dated as of such Closing Date, to the effect that they
reaffirm the statements made in the letter or letters furnished pursuant to
subsection (e) of this Section 7, except that any date specified therein as of
which certain procedures had been performed shall be a date not more than five
days prior to such Closing Date.

     (g) At the Closing Time, the Registration Rights Agreement, in form and
substance reasonably satisfactory to the Underwriter, shall have been duly
executed and delivered by Genentech and (assuming due execution, delivery and
performance by the Underwriter) shall be in full force and effect.

     (h) The Genentech Agreement shall have been duly authorized, executed and
delivered as of the date hereof and, at the Closing Time, the Genentech
Agreement shall be in full force and effect (assuming due execution, delivery
and performance by the Underwriter).

     If any of the conditions specified in this Section 7 shall not have been
fulfilled when and as required by this Agreement to be fulfilled (other than
conditions not satisfied because of a breach of the Underwriter's obligations
hereunder), this Agreement and all obligations of the Underwriter hereunder may
be canceled by the Underwriter by notifying the Company of such cancellation in
writing or by telegram, telex or telefax at any time prior to Closing Time, and
any such cancellation shall be without liability of any party to any other
party except as otherwise provided in Section 6; and provided further that
Section 8 hereof shall survive such cancellation and remain in full force and
effect.

     SECTION 8.  Indemnification; Contribution.

     (a) The Company agrees to indemnify and hold harmless the Underwriter, its
directors, officers and employees and each person, if any, who controls the
Underwriter within the meaning of Section 15 of the Securities Act, as follows:

          (i) against any and all loss, liability, claim, damage and expense
     whatsoever, as incurred, arising out of any untrue statement or alleged
     untrue statement of a material fact contained in the Disclosure Documents
     or the omission or alleged omission therefrom of a material fact necessary
     in order to make the statements therein, in the light of the circumstances
     under which they were made, not misleading (except as to any amount paid
     in settlement of, or any expense incurred in investigating, preparing or
     defending against, any litigation, or any investigation or proceeding by
     any governmental agency or body, commenced or threatened, or of any claim
     whatsoever based upon any such untrue statement or omission, or any such
     alleged untrue statement or omission, which shall be governed exclusively
     by (ii) and (iii) below);

          (ii) against any and all loss, liability, claim, damage and expense
     whatsoever, as incurred, to the extent of the aggregate amount paid in
     settlement of any litigation, or any investigation or proceeding by any
     governmental agency or body, commenced or threatened, or of any claim
     whatsoever based upon any such untrue statement or omission, or any such
     alleged untrue statement or omission, if such settlement is effected with
     the prior written consent of the Company; and

          (iii) against any and all expense whatsoever, as incurred (including,
     subject to Section 8(c) hereof, the reasonable fees and disbursements of
     counsel chosen by the Underwriter), reasonably incurred in investigating,
     preparing or defending against any litigation, or any investigation or
     proceeding by any governmental agency or body, commenced or threatened, or
     any claim whatsoever based upon any such untrue statement or omission, or
     any such alleged untrue statement or omission, to the extent that any such
     expense is not paid under (i) or (ii) above;

provided, however, that this indemnity agreement shall not apply to any loss,
liability, claim, damage or expense to the extent arising out of any untrue
statement or omission or alleged untrue statement or omission made in reliance
upon and in conformity with written information furnished to the Company by the
Underwriter expressly for use in the Offering Memorandum (or any amendment
thereto); provided further that the foregoing indemnity agreement is subject to
the condition that, insofar as it relates to any untrue statement or omission,
or any alleged untrue statement or omission, made in the Preliminary Offering
Memorandum but eliminated in the Final Offering Memorandum, such indemnity
agreement shall not inure to the benefit of the Underwriter if a copy of said
amended or supplemented Final


<PAGE>


Offering Memorandum was not delivered to the person asserting the claim and the
delivery thereof would have constituted a complete defense to the claim of such
person.

     (b) The Underwriter agrees to indemnify and hold harmless the Company,
each of its directors, and each person, if any, who controls the Company within
the meaning of Section 15 of the Securities Act against any and all loss,
liability, claim, damage and expense described in the indemnity contained in
subsection (a) of this section, as incurred, but only with respect to untrue
statements or omissions, or alleged untrue statements or omissions, made in the
Offering Memorandum (or any amendment or supplement thereto) in reliance upon
and in conformity with written information furnished to the Company by the
Underwriter expressly for use in such Offering Memorandum (or any amendment or
supplement thereto).

     (c) Each indemnified party shall give notice as promptly as reasonably
practicable to each indemnifying party of any action commenced against it in
respect of which indemnity may be sought hereunder, but failure so to notify an
indemnifying party shall not relieve such indemnifying party from any liability
hereunder to the extent it is not materially prejudiced as a result thereof and
in any event shall not relieve it from any liability which it may have
otherwise than on account of this indemnity agreement. An indemnifying party
may participate at its own expense in the defense of any such action. If it so
elects within a reasonable time after receipt of such notice, an indemnifying
party, jointly with any other indemnifying parties receiving such notice, may
assume the defense of such action with counsel chosen by it and approved (such
approval not to be unreasonably withheld) by the indemnified parties defendant
in such action, unless such indemnified parties object to such assumption on
the ground that there may be legal defenses available to them which are
different from or in addition to those available to such indemnifying party so
as to create, in the reasonable judgment of the indemnified parties, an actual
or potential conflict of interest. If an indemnifying party assumes the defense
of such action, the indemnifying parties shall not be liable for any fees and
expenses of counsel for the indemnified parties incurred thereafter in
connection with such action. In no event shall the indemnifying parties be
liable for fees and expenses of more than one counsel (in addition to any local
counsel) separate from their own counsel for all indemnified parties in
connection with any one action or separate but similar or related actions in
the same jurisdiction arising out of the same general allegations or
circumstances.

     (d) In order to provide for just and equitable contribution in
circumstances in which the indemnity agreement provided for in Section 8(a) or
(b) is for any reason held to be unenforceable by the indemnified parties
although applicable in accordance with its terms, the Company and the
Underwriter shall contribute to the aggregate losses, liabilities, claims,
damages and expenses of the nature contemplated by said indemnity agreement
incurred by the Company and the Underwriter, as incurred, (i) in such
proportions as is appropriate to reflect the relative benefits received by each
party from the offering of the Securities or (ii) if the allocation provided by
clause (i) is not permitted by applicable law, in such proportion as is
appropriate to reflect not only the relative benefits referred to in clause (i)
above but also the relative fault of the Company on the one hand and of the
Underwriter on the other hand in connection with the statements or omissions
which resulted in such losses, liabilities, claims, damages or expenses, as
well as any other relevant equitable considerations.

     The relative benefits received by the Company on the one hand and the
Underwriter on the other hand shall be deemed to be in the same proportion that
the total net proceeds from the sale of the Securities (before deducting
expenses) received by the Company bear to the underwriting discount received by
the Underwriter in respect thereof.

     The relative fault of the Company on the one hand and the Underwriter on
the other hand shall be determined by reference to, among other things, whether
any such untrue or alleged untrue statement of a material fact or omission or
alleged omission to state a material fact relates to information supplied by
the Company or by the Underwriter and the parties' relative intent, knowledge,
access to information and opportunity to correct or prevent such statement or
omission.

     The Company and the Underwriter agree that it would not be just and
equitable if contribution pursuant to this Section 8(d) were determined by pro
rata allocation or by any other method of allocation which does not take
account of the equitable considerations referred to above in this Section 8(d).
The aggregate amount of losses, liabilities, claims, damages and expenses
incurred by an indemnified party and referred to above in this Section 8(d)
shall be deemed to include any legal or other expenses reasonably incurred by
such indemnified party in investigating, preparing or defending against any
litigation, or any investigation or proceeding by any governmental agency or
body, commenced


<PAGE>


or threatened, or any claim whatsoever based upon any such untrue or alleged
untrue statement or omission or alleged omission.

     Notwithstanding the provisions of this Section 8(d), the Underwriter shall
not be required to contribute any amount in excess of the amount by which the
total offering price at which the Securities purchased by or through it were
sold exceeds the amount of any damages which the Underwriter has otherwise been
required to pay by reason of such actual or alleged statements in or omissions
from the Disclosure Documents.

     Notwithstanding the foregoing, no person guilty of fraudulent
misrepresentation (within the meaning of Section 11(f) of the Securities Act)
shall be entitled to contribution from any person who was not guilty of such
fraudulent misrepresentation.

     For purposes of this Section 8(d), each director, officer and employee of
the Underwriter and each person, if any, who controls the Underwriter within
the meaning of Section 15 of the Securities Act shall have the same rights to
contribution as the Underwriter, and each director of the Company and each
person, if any, who controls the Company within the meaning of Section 15 of
the Securities Act shall have the same rights to contribution as the Company.

     SECTION 9.  Representations, Warranties and Agreements to Survive Delivery.

     All representations, warranties, and agreements contained in this
Agreement shall remain operative and in full force and effect, shall not be
made subject to or qualified by any investigation made by or on behalf of the
Underwriter or controlling person thereof or by or on behalf of the Company,
and shall survive delivery of the Securities to the Underwriter.

     SECTION 10.  Underwriter's Undertaking, Offering of Securities.

     (a) The Securities have not been and will not be registered under the
Securities Act or registered under the securities or "blue sky" laws of any
state of the United States.

     (b) The Underwriter agrees that, in connection with any resale by it,
neither the Underwriter nor any of its affiliates will offer for resale or
resell the Securities purchased from the Company hereunder except (i) to those
institutions which the Underwriter reasonably believes are Qualified
Institutional Buyers and (ii) to persons other than U.S. persons (as defined in
Regulation S) to whom the Underwriter reasonably believes offers and sales of
the Securities may be made in reliance upon Regulation S.

     (c) The Underwriter will not offer or sell such securities in the United
States in any manner involving a public offering within the meaning of Section
4(2) of the Securities Act or by means of any form of general solicitation or
general advertising (as those terms are used in Regulation D under the
Securities Act), including, but not limited to, (x) any advertisement, article,
notice or other communication published in any newspaper, magazine or similar
media or broadcast over television or radio, or (y) any seminar or meeting
whose attendees have been invited by any general solicitation or general
advertising; (provided that such limitation shall not preclude the Underwriter
from placing (consistent with the Securities Act) any tombstone advertisement
with respect to the resale of the Securities following the later of the Closing
Date or the consummation of the resale of all of the Securities purchased
hereunder).

     (d) Neither the Underwriter, its affiliates nor any persons acting on its
or their behalf have engaged or will engage in any directed selling efforts
(within the meaning of Regulation S) with respect to the Securities or the
Genentech Common Stock offered pursuant to Regulation S, and the Underwriter,
its affiliates and any such persons have complied and will comply with the
offering restrictions requirements of Regulation S.

     (e) The Underwriter agrees that it will offer and sell the Securities only
in accordance with the offering and transfer restrictions described in the
Final Offering Memorandum.

     (f) The Underwriter represents that it is a "qualified institutional
buyer" within the meaning of Rule 144A under the Securities Act.


<PAGE>


     (g) The Underwriter agrees that it will sell, offer for sale and solicit
offers to buy the Securities only to or from persons that in purchasing such
Securities will be deemed to have represented and agreed as provided in the
Final Offering Memorandum under the caption "Transfer Restrictions."

     (h) The Underwriter acknowledges that neither the Company, Genentech nor
Roche has authorized the Underwriter or any other person to make any
representation or supply any information in connection with the offering of the
Securities other than as contained in the Offering Memorandum.

     (i) The Underwriter represents and agrees on behalf of itself and each of
its affiliates that (a) it has not offered or sold and, prior to the expiration
of the period of six months from the date hereof, will not offer or sell, any
Securities to persons in the United Kingdom except to persons whose ordinary
activities involve them in acquiring, holding, managing or disposing of
investments (as principal or agent) for the purposes of their businesses or
otherwise in circumstances which have not resulted and will not result in an
offer to the public in the United Kingdom within the meaning of the Public
Offers of Securities Regulations 1995, (b) it has complied and will comply with
all applicable provisions of the Financial Services Act 1986 with respect to
anything done by it in relation to the Securities in, from or otherwise
involving the United Kingdom, and (c) it has only issued or passed on and will
only issue and pass on in the United Kingdom any document received by it in
connection with the issue of the Securities to a person who is of a kind
described in Article 11(3) of the Financial Services Act 1986 (Investment
Advertisements) (Exemptions) Order 1996 or is a person to whom such document
may otherwise lawfully be issued or passed on.

     (j) The Underwriter represents and covenants that it will promptly notify
the Company and its counsel, Davis Polk & Wardwell (attention: Sarah J.
Beshar), upon completion of the distribution (within the meaning of Regulation
M under the Securities Act) of the Securities so as to allow the Company and
its affiliated purchasers (within the meaning of Regulation M under the
Securities Act) to comply timely with their obligations under Regulation M.

     SECTION 11.  Termination of this Agreement.

     The Underwriter shall have the right to terminate this Agreement (but only
after consultation with the Company if the Underwriter believes such
consultation to be reasonably practicable) by giving the notice indicated below
in this Section at any time at or prior to the Closing Time (i) if there shall
have been, since the respective dates as of which information is given in the
Final Offering Memorandum, and except as otherwise stated or contemplated
therein, any material adverse change in the condition, financial or otherwise,
of the Company and its subsidiaries considered as one enterprise, or of Roche
and its subsidiaries considered as one enterprise or of Genentech and its
subsidiaries considered as one enterprise, or in the earnings of the Company
and its subsidiaries considered as one enterprise, or of Roche and its
subsidiaries considered as one enterprise or of Genentech and its subsidiaries
considered as one enterprise, (ii) if since the date of this Agreement there
has occurred any outbreak or material escalation of hostilities or other
calamity or crisis the effect of which on the financial markets of the United
States is such as to make it, in the reasonable judgment of the Underwriter,
impracticable to market the Securities or to enforce contracts for the sale of
the Securities, or (iii) if the international financial markets shall have
undergone any change which is so material and adverse as to make it, in the
reasonable judgment of the Underwriter, impracticable to market the Securities
or to enforce contracts for the sale of the Securities. If the Underwriter
terminates this Agreement as provided in this Section, such termination shall
be without liability of any party to any other party except as otherwise
provided in Section 6 hereof, and provided further that Section 8 hereof shall
survive such termination and remain in full force and effect.

     If the Underwriter elects to prevent this Agreement from becoming
effective or to terminate this Agreement as provided in this Section, the
Company shall be notified immediately by the Underwriter, by telephone or
telegram, confirmed by letter.

     SECTION 12.  Notices.

     All communications hereunder shall be in writing and, if sent to the
Underwriter, shall be mailed, delivered or telegraphed and confirmed to Merrill
Lynch & Co., Merrill Lynch, Pierce, Fenner & Smith Incorporated, World
Financial Center, North Tower, New York, New York 10281, Attention: Andrew
Burch, or, if sent to the Company, shall be mailed, delivered or telegraphed
and confirmed to Roche Holdings, Inc., 1201 N. Orange St., One Commerce Center,
Suite 1050, Wilmington, Delaware 19801, Attention: Secretary, or, if sent to
Genentech, shall be mailed, delivered or


<PAGE>


telegraphed and confirmed to Genentech, Inc., 1 DNA Way, South San Francisco,
California 94080-4990, Attention: General Counsel.

     SECTION 13.  Parties.

     This Agreement shall inure to the benefit of and be binding upon the
Underwriter, the Company and their respective successors. Nothing expressed or
mentioned in this Agreement is intended or shall be construed to give any
person, other than the parties hereto and their respective successors, heirs
and legal representatives and the controlling persons of the Underwriter and
the Company referred to in Section 8, any legal or equitable right, remedy or
claim under or in respect of this Agreement or any provision herein contained,
this Agreement and all conditions and provisions hereof being intended to be
and being for the sole and exclusive benefit of the parties hereto and their
respective successors, heirs and legal representatives and said controlling
persons, and for the benefit of no other person. No purchaser of any Securities
from the Underwriter shall be deemed to be a successor by reason merely of such
purchase.

     SECTION 14.  Governing Law and Jurisdiction, Miscellaneous.

     (a) This Agreement shall be governed by and construed in accordance with
the laws of the State of New York applicable to agreements made and to be
performed wholly within such jurisdiction. Each of the parties hereto hereby
expressly and irrevocably submits to the non-exclusive jurisdiction of any
competent court in the place of its domicile and any United States Federal or
New York State court sitting in the Borough of Manhattan, City and State of New
York in any action or proceeding arising out of or relating to this Agreement
to the extent that such court has subject matter jurisdiction over the
controversy, and expressly and irrevocably waives, to the extent permitted
under applicable law, any immunity from the jurisdiction thereof and any claim
or defense in such action or proceeding based on a claim of improper venue,
forum non conveniens or any similar basis to which it might otherwise be
entitled in any such action or proceeding.

     (b) The headings of the sections of this Agreement have been inserted for
convenience of reference only and shall not be deemed a part of this Agreement.

     (c) This Agreement may be signed in any number of counterparts, each of
which shall be an original, with the same effect as if the signatures thereto
and hereto were upon the same instrument.


<PAGE>


     If the foregoing is in accordance with your understanding of our
agreement, please sign and return to us a counterpart hereof, whereupon this
instrument will become a binding agreement among the Underwriter and the
Company in accordance with its terms.

                                         Very truly yours,


                                         ROCHE HOLDINGS, INC.


                                         By: /s/ Bruno Maier
                                            -----------------------------------
                                            Name:  Dr. Bruno Maier
                                            Title: Authorized Signatory

                                         By: /s/ Bernd Wolff
                                            -----------------------------------
                                            Name:  Bernd Wolff
                                            Title: Authorized Signatory


CONFIRMED AND ACCEPTED
as of the date first above written:

MERRILL LYNCH, PIERCE, FENNER & SMITH
INCORPORATED


By /s/ Andrew Burch
  ---------------------------------
  Name:  Andrew Burch
  Title: Vice President, Authorized Signatory


<PAGE>


                                                                     SCHEDULE A

                              ROCHE HOLDINGS, INC.

                  $1,506,342,000 Principal Amount at Maturity
                     Liquid Yield Option(TM) Notes due 2015
                                 (Zero Coupon)

     1. The initial offering price per $1,000 principal amount at maturity of
Securities shall be $663.86, representing a yield to maturity of 2.75% per
annum (computed on a semiannual bond equivalent basis).

     2. The Securities shall be exchangeable for shares of Genentech Common
Stock at an initial exchange rate of 4.32658 shares per $1,000 principal amount
at maturity of Securities. The foregoing is subject to the right of the
Company, in accordance with the terms and subject to the conditions set forth
in the Indenture and the Securities, to pay cash equal to market value of the
Genentech Common Stock in lieu of delivering shares of Genentech Common Stock.

     3. The purchase price per $1,000 principal amount at maturity of
Securities to be paid by the Underwriter shall be $650.58, being an amount
equal to the initial offering price set forth above, less $13.28 per $1,000
principal amount at maturity of Securities.

     4. Prior to January 19, 2004, the Securities will not be redeemable. The
redemption prices of the Securities to be included in the Indenture shall be as
follows:

                                                              (3)
                                (1)             (2)       Redemption
                               LYON          Accrued         Price
Redemption Date            Issue Price    OID at 2.75%     (1) + (2)
---------------            -----------    ------------    -----------
January 19, 2004..........  $  663.86       $  76.63         740.49
January 19, 2005..........  $  663.86          97.14         761.00
January 19, 2006..........  $  663.86         118.21         782.07
January 19, 2007..........  $  663.86         139.86         803.72
January 19, 2008..........  $  663.86         162.12         825.98
January 19, 2009..........  $  663.86         184.99         848.85
January 19, 2010..........  $  663.86         208.49         872.35
January 19, 2011..........  $  663.86         232.65         896.51
$anuary 19, 2012..........  $  663.86         257.47         921.33
January 19, 2013..........  $  663.86         282.98         946.84
January 19, 2014..........  $  663.86         309.20         973.06
At Maturity...............  $  663.86         336.14       1,000.00

     5. The purchase price applicable to the purchase of Securities at the
option of the holders at a Purchase Date (as defined in the Indenture) shall be
as follows:

                     Purchase Price        Purchase Price
                     --------------        --------------
                    January 19, 2004         $  740.49
                    January 19, 2010         $  872.35


<PAGE>


                                                                      EXHIBIT A

                       Form of Opinion of Dr. Bruno Maier

     (i) Roche has been duly incorporated and is validly existing as a joint
stock company in good standing under the laws of Switzerland, with corporate
power and authority to own its properties and conduct its business as described
in the Final Offering Memorandum.

     (ii) Roche is duly qualified as a foreign corporation to transact business
and is in good standing in each jurisdiction in which such qualification is
required, whether by reason of the ownership or leasing of property or the
conduct of business, except where the failure to be so qualified would not have
a material adverse effect on the condition, financial or otherwise, or earnings
of Roche and its subsidiaries considered as one enterprise.

     (iii) F. Hoffmann-La Roche Ltd has been duly incorporated and is validly
existing as a corporation in good standing under the laws of Switzerland, with
corporate power and authority to own its properties and conduct its business as
described in the Final Offering Memorandum or as otherwise currently conducted.

     (iv) F. Hoffman-La Roche Ltd is duly qualified as a foreign corporation to
transact business and is in good standing in each jurisdiction in which such
qualification is required, whether by reason of the ownership or leasing of
property or the conduct of business, except where the failure to be so
qualified would not have a material adverse effect on the condition, financial
or otherwise, or earnings of Roche and its subsidiaries considered as one
enterprise.

     (v) All of the issued and outstanding capital stock of F. Hoffman-La Roche
Ltd has been duly authorized and validly issued and is fully paid and
nonassessable, all of the capital stock of F. Hoffmann-La Roche Ltd is owned by
Roche, directly or through other subsidiaries, free and clear of any material
security interest, mortgage, pledge, lien or encumbrance.

     (vi) All of the capital stock of the Company and Hoffmann-La Roche Inc. is
owned by Roche, directly or through other subsidiaries, free and clear of any
material security interest, mortgage, pledge, lien or encumbrance.

     (vii) As of the date of such opinion, the shares of Genentech Common Stock
to be delivered by the Company in exchange for the Securities as provided in
the Indenture are owned directly by the Company free and clear of any security
interest, mortgage, pledge, lien or encumbrance.

     (viii) The execution and delivery by Roche of the Guarantee Agreement and
the Keep Well Agreement, the incurrence of the obligations therein set forth,
the consummation of the transactions therein contemplated, and compliance with
the terms thereof have been duly and validly authorized by all necessary
corporation action under the laws of Switzerland and the charter and by-laws of
Roche, and, to the best of such counsel's knowledge, will not conflict with or
result in a breach of any existing provisions of the laws or regulations of
Switzerland or of the terms of the constitutive documents of Roche or of any
other material restriction, whether statutory or otherwise, or of any material
order, judgment or decree to which Roche is a party, or materially conflict
with, or result in a material breach of any material agreement or other
material instrument, whether contractual or otherwise, to which Roche is bound.

     (ix) The Keep Well Agreement constitutes the valid and binding agreement
of Roche enforceable against it in accordance with its terms, except as
enforcement thereof may be limited by bankruptcy, insolvency or other laws
relating to or affecting enforcement of creditors' rights or by general
equitable principles.

     (x) There are no approvals, authorizations, consents, orders,
registrations or qualifications from or with any court or governmental agency
or body required in Switzerland for the issuance and sale to the Underwriter of
the Securities, for the execution of the Guarantee Agreement or the Keep Well
Agreement or, as of the date hereof, for the issuance and delivery of the
shares of Genentech Common Stock upon exchanges of the Securities (except such
as may be required under the state securities or "blue sky" laws of any
jurisdiction, as to which such counsel need not express any opinion).


<PAGE>


     (xi) To the best of such counsel's knowledge, there is no Swiss stamp,
documentary, registration or similar duty or tax payable in connection with the
issuance, sale or delivery of the Securities to the Underwriter. Subsequent
sales and purchases of the Securities and the exchange of shares of Genentech
Common Stock for the Securities in accordance with the Indenture is subject to
Swiss stamp duty on turnover of securities if the holder of the Securities
qualifies as a "dealer in securities" under Swiss stamp duty law.

     (xii) Except as disclosed in the Final Offering Memorandum, there is no
action, suit or proceeding, pending or, to the best of such counsel's
knowledge, threatened, to which Roche, the Company or any Subsidiary is a party
or, to the best of such counsel's knowledge, affecting Roche, the Company or
any of the Subsidiaries, before or by any court or governmental agency or body,
Swiss or, to the best of such counsel's knowledge, non-Swiss, other than
proceedings, suits or actions that would not, singly or in the aggregate,
result in any material adverse change in the condition, financial or otherwise,
or earnings of the Company and its subsidiaries considered as one enterprise or
of Roche and its subsidiaries considered as one enterprise.

     (xiii) To the best of such counsel's knowledge and except as disclosed in
the Final Offering Memorandum, neither Roche nor any of the Subsidiaries has
received any notice of infringement of or conflict with asserted rights of
others with respect to any patents, patent rights, licenses or trade secrets
which might reasonably be expected, singly or in the aggregate, to result in
any material adverse change in the condition, financial or otherwise, or
earnings of the Company and its subsidiaries considered as one enterprise or of
Roche and its subsidiaries considered as one enterprise.

     (xiv) All statements in the Final Offering Memorandum with respect to or
involving matters of the law of Switzerland or Swiss documents or proceedings
fairly summarize in all material respects the information referred to therein;
and the statements in the Final Offering Memorandum under the caption "Certain
Tax Considerations Under Swiss Law", insofar as such statements purport to
summarize the laws of Switzerland referred to thereunder, fairly summarize such
laws in all material respects as to the matters referred to therein.

     (xv) The provision in the Guarantee Agreement as to the choice of New York
law to be the law governing the agreement, and the submission of Roche to the
jurisdiction of the United States Federal, New York State courts sitting in the
Borough of Manhattan, the City and the State of New York in any action under
the Guarantee Agreement, are valid, binding and enforceable under Swiss law;
and judgments obtained under the Guarantee Agreement in any such action shall
be enforceable in Switzerland, including, without limitation, any final
judgment for the payment of money rendered by any court pursuant thereto,
except as enforcement may be limited by general principles of equity
(regardless of whether such enforceability is considered in a proceeding in
equity or at law).

     (xvi) Roche has the power to submit, and pursuant to the Guarantee
Agreement has legally, validly, effectively and irrevocably submitted, to the
non-exclusive jurisdiction of any federal or state court in the State of New
York, County of New York with respect to actions or proceedings arising out of
or relating to the Guarantee Agreement.

     Without assumption of any responsibility for the factual accuracy or
completeness of matters of fact contained in the Final Offering Memorandum,
nothing has come to such counsel's attention to cause that counsel to believe
that the Final Offering Memorandum (except for the financial statements and
schedules and other financial or statistical information included therein, as
to which such counsel need not express a belief) contained any untrue statement
of the material fact or omitted to state any material fact necessary in order
to make the statements therein, in the light of the circumstances under which
they were made, not misleading, at the date of the Purchase Agreement or so
contains or omits at the date hereof.


<PAGE>


                                                                      EXHIBIT B

                    Form of Opinion of Davis Polk & Wardwell

     (i) The Company has been duly incorporated and is validly existing as a
corporation in good standing under the laws of the State of Delaware, with
corporate power and authority to own its properties and conduct its business as
described in the Final Offering Memorandum or as otherwise currently conducted.

     (ii) The Company is duly qualified as a foreign corporation to transact
business and is in good standing in each jurisdiction in which such
qualification is required, whether by reason of the ownership or leasing of
property or the conduct of business, except where the failure to be so
qualified would not have a material adverse effect on the condition, financial
or otherwise, or earnings of the Company and its subsidiaries considered as one
enterprise or of Roche and its subsidiaries consider as one enterprise.

     (iii) Genentech is validly existing as a corporation in good standing
under the laws of the State of Delaware, with corporate power and authority to
own its properties and conduct its business as described in the Final Offering
Memorandum.

     (iv) The Purchase Agreement has been duly and validly authorized, executed
and delivered by the Company and (assuming the due authorization, execution and
delivery by the Underwriter) constitutes a valid and binding agreement of the
Company enforceable against it in accordance with its terms, except as
enforcement thereof may be limited by bankruptcy, insolvency or other laws
relating to or affecting enforcement of creditors' rights or by general
equitable principles and except as rights to indemnity and contribution may be
limited by applicable law.

     (v) Each of the Genentech Agreement and the Registration Rights Agreement
has been duly and validly authorized, executed and delivered by Genentech and
(assuming the due authorization, execution and delivery by the Underwriter)
constitutes a valid and binding agreement of Genentech enforceable against it
in accordance with its terms, except as enforcement thereof may be limited by
bankruptcy, insolvency or other laws relating to or affecting enforcement of
creditors' rights or by general equitable principles and except as rights to
indemnity and contribution may be limited by applicable law.

     (vi) The authorized capital stock of Genentech conforms as to legal
matters to the description thereof contained in the Final Offering Memorandum.

     (vii) Assuming it has been duly authorized, executed and delivered by
Roche, the Guarantee Agreement constitutes a valid and binding agreement of
Roche enforceable against it in accordance with its terms, except as
enforcement thereof may be limited by bankruptcy or other laws relating to or
affecting enforcement of creditors' rights or by general equitable principles
and except as rights to indemnity and contribution may be limited by applicable
law.

     (viii) The Securities have been duly and validly authorized for issuance
and sale to the Underwriter pursuant to the Purchase Agreement and, when
executed, authenticated and delivered in the manner provided for in the
Indenture against payment of the consideration therefor in accordance with the
Purchase Agreement, will be duly issued and will constitute valid and legally
binding obligations of the Company enforceable against it in accordance with
their terms (except as enforcement thereof may be limited by bankruptcy,
insolvency or other laws relating to or affecting enforcement of creditors'
rights or by general equitable principles); and the Securities will be entitled
to the benefits of the Indenture and the Registration Rights Agreement.

     (ix) The Company has all necessary corporate power and authority to
execute and deliver the Indenture and to perform its obligations thereunder;
the Indenture has been duly and validly authorized, executed and delivered by
the Company and (assuming the due authorization, execution and delivery by the
Trustee) constitutes the valid and legally binding obligation of the Company
enforceable against it in accordance with its terms, except as enforcement
thereof may be limited by bankruptcy, insolvency or other laws relating to or
affecting enforcement of creditors' rights or by general equitable principles;
and the Indenture is not required to be qualified under the Trust Indenture Act
of 1939, as amended.


<PAGE>


     (x) The statements in the Final Offering Memorandum under the caption
"Description of LYONs" and the statements in the Registration Statement under
the caption "Description of Capital Stock", as such statements may have been
amended or supplemented by any Genentech Disclosure filed or made subsequent to
the time the Registration Statement became effective, insofar as such
statements purport to summarize the terms of the Securities and the Genentech
Common Stock and other documents referred to thereunder, fairly summarize such
terms of the Securities and the Genentech Common Stock and other documents in
all material respects.

     (xi) The execution and delivery by the Company of the Purchase Agreement
and the Indenture, the incurrence of the obligations therein set forth, the
consummation of the transactions therein contemplated, and compliance with the
terms thereof have been duly and validly authorized by all necessary corporate
action under the laws of the State of Delaware and the charter and by-laws of
the Company, and, to the best of such counsel's knowledge, will not (A)
conflict with or result in a breach of (1) any existing provisions of the laws
or regulations of the United States of America or the State of New York or of
the terms of the constitutive documents of the Company or any other material
statutory restriction, or (2) any other material restriction or any material
order, judgment or decree to which the Company is a party, or (B) materially
conflict with, or result in a material breach of any material agreement or
other material instrument, whether contractual or otherwise, to which the
Company is bound; provided, however, that with respect to the opinions in
clauses (A)(2) and (B) above, such counsel may state that, in connection with
the offering of the LYONs, they have not conducted a review of corporate
documents of the Company as would customarily be performed in connection with
rendering such opinions.

     (xii) The execution and delivery by Genentech of the Genentech Agreement
and the Registration Rights Agreement, the incurrence of the obligations
therein set forth, the consummation of the transactions therein contemplated,
and compliance with the terms thereof have been duly and validly authorized by
all necessary corporate action under the laws of the State of Delaware and the
charter and by-laws of Genentech, and, to the best of such counsel's knowledge,
will not conflict with or result in a breach of any existing provisions of the
laws or regulations of the United States of America or the State of New York or
of the terms of the constitutive documents of Genentech.

     (xiii) There are no approvals, authorizations, consents, orders,
registrations or qualifications of or with any court or governmental agency or
body of the United States or the State of New York required for the sale to the
Underwriter of the Securities, for the delivery of the Genentech Common Stock
upon exchanges of the Securities as provided in the Indenture or for the
execution of the Purchase Agreement, the Genentech Agreement, the Guarantee
Agreement, the Registration Rights Agreement or the Keep Well Agreement (except
such as may be required under state securities or "blue sky" laws of any
jurisdiction, as to which we express no opinion).

     (xiv) The statements in the Final Offering Memorandum under the caption
"Certain Federal Income Tax Considerations," insofar as such statements purport
to summarize federal laws of the United States referred to thereunder, fairly
summarize such laws in all material respects.

     (xv) It is not necessary, in connection with the offer, sale and delivery
of the Securities to the Underwriter under the Purchase Agreement and the
initial resales by the Underwriter in the manner contemplated by the Purchase
Agreement and the Final Offering Memorandum, to register such Securities under
the Securities Act of 1933, as amended (it being understood that no opinion is
expressed as to any other offer or resale of any securities). In rendering the
opinion in this paragraph (xv), we have (i) assumed the accuracy of the
representations of the Underwriter, the Company and Roche contained in the
Purchase Agreement and the letter dated January 12, 2000 from Roche to the
Underwriter, and that the offer, sale and delivery of the Securities have been
made as contemplated by the Purchase Agreement and (ii) relied upon the
no-action letters issued by the Staff of the Commission to Black Box, Inc.
(dated June 26, 1990) and Squadron, Ellenoff, Pleasant & Lehrer (dated February
28, 1992) and assumed that a court would give effect to the positions taken by
the Staff in such no-action letters as applicable law.

     The opinions set forth in clauses (xiii) and (xv) above are based on the
facts and circumstances contemplated by the Offering Memorandum and the
accuracy of the representations and warranties in the Purchase Agreement and
the Genentech Agreement and compliance with the Underwriter's undertakings in
the Purchase Agreement.

     We have not ourselves checked the accuracy or completeness of, or
otherwise verified, the information furnished with respect to other matters in
the Final Offering Memorandum. We have generally reviewed and discussed with
your


<PAGE>


representatives and with certain officers and employees of, the counsel and
independent accountants for, the Company, Roche and Genentech the information
furnished, whether or not subject to our check and verification, but we have
not conducted a review of corporate documents of the Company and Roche as would
customarily be performed by counsel in connection with an offering of
securities registered under the Securities Act of 1933, as amended. On the
basis of such consideration, review and discussion, but without independent
check or verification, except as stated, no facts have come to our attention
that lead us to believe that (except for the financial statements and schedules
and other financial or statistical data contained therein, as to which we are
not called upon to express any belief) the Final Offering Memorandum, as of the
date of the Purchase Agreement, did, and, as of the date hereof does, contain
any untrue statement of a material fact or omit to state any material fact
necessary in order to make the statements therein, in the light of the
circumstances under which they were made not misleading.


<PAGE>


                                                                      EXHIBIT C

                   Form of Opinion of Frederick C. Kentz III

     (i) Hoffmann-La Roche Inc. has been duly incorporated and is validly
existing as a corporation in good standing under the law of the State of New
Jersey, with corporate power and authority to own its properties and conduct
its business as described in the Final Offering Memorandum or as otherwise
currently conducted.

     (ii) Hoffmann-La Roche Inc. is duly qualified as foreign corporation to
transact business and is in good standing in each jurisdiction in which such
qualification is required, whether by reason of the ownership or leasing of
property or the conduct of business, except where the failure to be so
qualified would not have a material adverse effect on the condition, financial
or otherwise, or earnings of the Company and its subsidiaries considered as one
enterprise or of Roche and its subsidiaries considered as one enterprise.