<PAGE>

                                                          Exhibit 4.02

THIS WARRANT AND THE SHARES ISSUABLE HEREUNDER HAVE NOT BEEN REGISTERED UNDER
THE SECURITIES ACT OF 1933, AS AMENDED, AND MAY NOT BE SOLD, PLEDGED, OR
OTHERWISE TRANSFERRED WITHOUT AN EFFECTIVE REGISTRATION THEREOF UNDER SUCH ACT
OR PURSUANT TO RULE 144 OR AN OPINION OF COUNSEL REASONABLY SATISFACTORY TO THE
CORPORATION AND ITS COUNSEL, THAT SUCH REGISTRATION IS NOT REQUIRED.

THIS SECURITY IS SUBJECT TO CERTAIN RESTRICTIONS UPON TRANSFER, INCLUDING BUT
NOT LIMITED TO A RIGHT OF FIRST OFFER ON BEHALF OF THE COMPANY, AS SET FORTH IN
AN AGREEMENT BETWEEN THE COMPANY AND THE STOCKHOLDER, A COPY OF WHICH IS ON FILE
WITH THE SECRETARY OF THE COMPANY.


                            WARRANT TO PURCHASE STOCK

Corporation:                 Adaptec, Inc.
Number of Shares:            464,000
Class of Stock:              Common Stock
Initial Exercise Price:      $62.25 per share
Issue Date:                  January 17, 2000
Expiration Date:             January 16, 2004

         This Warrant certifies that, for good and valuable consideration,
Agilent Technologies, Inc., a Delaware corporation ("HOLDER") is entitled to
purchase from the corporation named above (the "COMPANY"), until 5:00 p.m.
Pacific standard time, on the Expiration Date set forth above, the number of
fully paid and nonassessable shares of the Common Stock (the "SHARES") of the
Company at the initial exercise price per Share (the "WARRANT PRICE"), all as
set forth above and as adjusted pursuant to Section 2 of this Warrant, subject
to the provisions and upon the terms and conditions set forth in this Warrant.

1.       EXERCISE.

         1.1 VESTING; EXERCISE. As of the Issue Date, this Warrant shall be
exercisable in full by Holder, and Holder may exercise this Warrant, in whole or
in part, by delivering a duly executed Notice of Exercise in substantially the
form attached as EXHIBIT A to the principal office of the Company. Unless Holder
is exercising the conversion right set forth in Section 1.6, Holder shall also,
concurrently with delivery of the Notice of Exercise, deliver to the Company a
check or wire transfer in United States dollars for the aggregate Warrant Price
for the Shares being purchased.

         1.2 DELIVERY OF CERTIFICATE AND NEW WARRANT. Promptly after Holder
exercises this Warrant, the Company shall deliver to Holder certificates for the
Shares acquired and, if this Warrant has not been fully exercised or converted
and has not expired, this Warrant shall automatically be reduced by the number
of Shares as to which the Warrant has been exercised and remain exercisable for
such remaining Shares as to which this Warrant has not been exercised, and all
other terms of the Warrant shall otherwise remain in full force and effect as so
adjusted. Upon final exercise of this Warrant for any such remaining number of
Shares, this Warrant shall be surrendered by the Holder to the Company for
cancellation.

         1.3 REPLACEMENT OF WARRANTS. On receipt of evidence reasonably
satisfactory to the Company of the loss, theft, destruction or mutilation of
this Warrant and, in the case of loss, theft or destruction, on delivery of an
indemnity agreement reasonably satisfactory in form and amount to the Company
or, in the case of mutilation, or surrender and cancellation of this Warrant,
the Company at its expense shall execute and deliver, in lieu of this Warrant, a
new warrant of like tenor.

         1.4      SALE, MERGER, OR CONSOLIDATION OF THE COMPANY.

                  1.4.1. "ACQUISITION". For the purpose of this Warrant,
"ACQUISITION" means any sale of the Company's stock by the Company's
stockholders in one transaction or series of related transactions or any


                                      1
<PAGE>

reorganization, consolidation or merger of the Company, in any case where,
after the transaction, the holders of the Company's securities before the
transaction beneficially own less than fifty percent (50%) of the outstanding
voting securities of the surviving entity or of its parent corporation if the
surviving entity is a wholly owned subsidiary of such parent corporation.

                  1.4.2 ASSUMPTION OF WARRANT. Upon the closing of any
Acquisition where the consideration for the Acquisition to be received by the
Company's stockholders consists solely of stock or securities of the acquirer or
an entity affiliated with the acquirer, the successor entity shall assume the
obligations of this Warrant, and this Warrant shall be exercisable for the same
securities as would be payable for the Shares issuable upon exercise of the
unexercised portion of this Warrant as if such Shares were outstanding on the
record date for the Acquisition and subsequent closing thereof. The Warrant
Price shall be adjusted accordingly.

                  1.4.3 TERMINATION OF WARRANT. In the case of (a) an
Acquisition where the consideration for the Acquisition to be received by the
Company's stockholders in return for their capital stock of the Company consists
of cash or a combination of cash and other property or (b) the proposed
liquidation and dissolution of the Company, the Company shall give Holder at
least fifteen (15) days advance written notice of such event (the "COMPANY
NOTICE"), which notice shall include the Company's best estimate of the value of
the Shares receivable upon exercise or conversion of this Warrant and the
proposed date upon which such event is expected to occur. During such notice
period, Holder may exercise or convert this Warrant in accordance with its
terms, whether or not exercise or conversion is contingent upon the happening of
such event. Subject to prior exercise or conversion as provided in the preceding
sentence, this Warrant will terminate at 5:00 p.m. Pacific time on the day prior
to the date such event is expected to occur as set forth in the Company Notice;
PROVIDED THAT the event actually occurs within sixty (60) days after the date it
is expected to occur, as such date was specified in the Company Notice.

         1.5 RESTRICTIONS ON EXERCISE. This Warrant may not be exercised if the
issuance of the Shares upon such exercise would constitute a violation of any
applicable federal or state securities laws or other laws or regulations. As a
condition to the exercise of this Warrant, by the Holder's execution of the
Notice of Exercise attached hereto as EXHIBIT A, the Holder shall confirm,
acknowledge and agree to the representations, warranties and agreements of the
Holder set forth in Section 4 hereof.

         1.6 NET EXERCISE ELECTION. The Holder may elect to convert all or a
portion of this Warrant, without the payment by the Holder of any additional
consideration, by the surrender of this Warrant or such portion of this Warrant
to the Company, with the net exercise election selected in the Notice of
Exercise attached hereto as EXHIBIT A duly executed by the Holder, into up to
the number of Shares that is obtained under the following formula:

                                   X = Y (A-B)
                                       -------
                                           A

where             X =  the number of Shares to be issued to the Holder
                       pursuant to this Section 1.5.

                  Y =  the number of Shares as to which this Warrant is
                       being exercised.

                  A =  the fair market value of one Share, as determined in
                       good faith by the Company's Board of Directors, as at
                       the time the net exercise election is made pursuant
                       to this Section 1.5.

                  B =  the Warrant Price.

         The Company will promptly respond in writing to an inquiry by the
Holder as to the then current fair market value of one Share.

         For purposes of the above calculation, fair market value of one Share
shall be determined by the Company's Board of Directors in good faith; provided,
however, that where there exists a public market for the Company's Common Stock
at the time of such exercise, the fair market value per share shall be the
average of the closing bid and asked prices of the Common Stock quoted in the
Over-The-Counter Market Summary or the last reported sale price of the Common
Stock or the closing price quoted on the Nasdaq National Market or on any
exchange on which the Common Stock is listed, whichever is applicable, as
published in the Western Edition of THE WALL STREET JOURNAL for the three (3)
trading days prior to the date of determination of fair market value.


                                      2
<PAGE>

2.       ADJUSTMENTS TO THE SHARES.

         2.1 STOCK SPLITS, RECAPITALIZATIONS, ETC. If the Company (i) pays a
dividend in, or makes a distribution of, shares of capital stock or other
securities on its outstanding Common Stock, (ii) subdivides its outstanding
shares of Common Stock in a transaction that increases the amount of its
outstanding shares of Common Stock, or (iii) combines its outstanding shares of
Common Stock in a transaction that decreases the amount of its outstanding
shares of Common Stock, then upon exercise or conversion of this Warrant, for
each Share acquired, Holder shall receive, without cost to Holder, the total
number and kind of securities to which Holder would have been entitled had
Holder owned the Shares of record as of the date such dividend, distribution,
subdivision or combination occurred.

         2.2 CERTAIN CORPORATE TRANSACTIONS. Upon any reclassification,
exchange, substitution, Acquisition of the Company or other similar event that
results in a change of the number and/or class of the securities issuable upon
exercise or conversion of this Warrant other than as provided in Section 2.1 (a
"REORGANIZATION"), Holder shall be entitled to receive, upon exercise or
conversion of this Warrant, the number and kind of securities and property that
Holder would have received for the Shares if this Warrant had been exercised
immediately before such Reorganization. The Company or its successor shall
promptly issue to Holder a new Warrant for such new securities or other
property. The new Warrant shall provide for adjustments that shall be as nearly
equivalent as may be practicable to the adjustments provided for in this Section
2 including, without limitation, appropriate adjustments to the Warrant Price
and to the number of securities or property issuable upon exercise or conversion
of the new Warrant.

         2.3 ADJUSTMENTS OF WARRANT PRICE. If the outstanding Shares are
combined or consolidated, by reclassification or otherwise, into a lesser number
of shares, the Warrant Price shall be proportionately increased. If the
outstanding Shares are divided by reclassification or otherwise, into a greater
number of shares, the Warrant Price shall be proportionately decreased.

         2.4 ADJUSTMENT IS CUMULATIVE. The provisions of this Section 2 shall
similarly apply to successive, stock dividends, stock splits or combinations,
reclassifications, exchanges, substitutions, or other events.

         2.5 NO IMPAIRMENT. The Company shall not, by amendment of its
Certificate of Incorporation or through a reorganization, transfer of assets,
consolidation, merger, dissolution, issue, or sale of securities or any other
voluntary action, avoid or seek to avoid the observance or performance of any of
the terms to be observed or performed under this Warrant by the Company, but
shall at all times carry out of all the provisions of this Section 2.

         2.6 FRACTIONAL SHARES. No fractional Shares shall be issuable upon
exercise or conversion of the Warrant and the number of Shares to be issued
shall be rounded down to the nearest whole Share. If a fractional share interest
arises upon any exercise or conversion of the Warrant, the Company shall
eliminate such fractional Share interest by paying Holder an amount by check
computed by multiplying the fractional interest by the fair market value of a
full Share.

         2.7 CERTIFICATE AS TO ADJUSTMENTS. Upon each adjustment of the Warrant
Price, the Company at its expense shall compute such adjustment, and furnish
Holder with a certificate of its Chief Financial Officer setting forth such
adjustment and the facts upon which such adjustment is based. The Company shall,
upon written request, furnish Holder a certificate setting forth the Warrant
Price in effect upon the date thereof and the series of adjustments leading to
such Warrant Price.

3.       REPRESENTATIONS AND COVENANTS OF THE COMPANY.

         3.1 REPRESENTATIONS AND WARRANTIES. The Company hereby represents and
warrants to the Holder that all Shares which may be issued upon the exercise of
the purchase right represented by this Warrant, and all securities, if any,
issuable upon conversion of the Shares, shall, upon issuance, be duly
authorized, validly issued, fully paid and nonassessable, and free of any liens
and encumbrances except for restrictions on transfer provided for herein or
under applicable federal and state securities laws.

         3.2 RESERVATION OF THE SHARES. If at any time the number of shares of
Common Stock or other securities issuable upon exercise of this Warrant shall
not be sufficient to effect the exercise of this Warrant, the


                                      3
<PAGE>

Company will take such corporate action as may, in the opinion of its
counsel, be necessary to increase its authorized but unissued shares of
Common Stock or other securities issuable upon exercise of this Warrant as
shall be sufficient for such purpose.

         3.3 NO RIGHTS OR LIABILITIES AS STOCKHOLDER. This Warrant does not by
itself entitle the Holder to any voting rights, cash dividends or other rights,
nor subject Holder to any liabilities, as a stockholder of the Company. In the
absence of affirmative action by the Holder to purchase Shares by exercise of
this Warrant, no provisions of this Warrant, and no enumeration herein of the
rights or privileges of the Holder, shall cause the Holder to be a stockholder
of the company for any purpose.

4.       REPRESENTATIONS OF HOLDER; TRANSFER.

         4.1 REPRESENTATIONS. Holder hereby represents and warrants to the
Company as follows: Holder is a sophisticated investor having such knowledge and
experience in business and investment matters that Holder is capable of
protecting Holder's own interests in connection with the acquisition, exercise
or disposition of this Warrant. Holder is an "accredited investor" within the
meaning of Regulation D promulgated under the Securities Act of 1933, as amended
(the "ACT"). Holder is aware that this Warrant and the Shares (and the
securities issuable, directly or indirectly, upon conversion of the Shares, if
any) (hereinafter, collectively, the "RESTRICTED SECURITIES") are being, or will
be, issued to Holder in reliance upon Holder's representation in this Section 4
and that such securities are restricted securities that cannot be publicly sold
except in certain prescribed situations. Holder is aware of the provisions of
Rule 144 promulgated under the Act and of the conditions under which sales may
be made thereunder. Holder has received such information about the Company as
Holder deems reasonable, has had the opportunity to ask questions and receive
answers from the Company with respect to its business, assets, prospects and
financial condition and has verified any answers Holder has received from the
Company with independent third parties to the extent Holder deems necessary. The
Holder, by acceptance hereof, acknowledges that the Restricted Securities are
being acquired solely for the Holder's own account and not as a nominee for any
other party, and for investment, and that the Holder will not offer, sell or
otherwise dispose of this Warrant or any Shares to be issued upon exercise
hereof or conversion thereof except under circumstances that will not result in
a violation of the Act or any state securities laws.

         4.2 LEGENDS. The Restricted Securities shall be imprinted with legends
in substantially the following form:

         THIS SECURITY HAS NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933,
         AS AMENDED, OR ANY STATE SECURITIES LAW AND MAY NOT BE SOLD, PLEDGED OR
         OTHERWISE TRANSFERRED WITHOUT AN EFFECTIVE REGISTRATION THEREOF UNDER
         SUCH ACT OR LAW OR PURSUANT TO RULE 144 AND ANY STATE EXEMPTION FROM
         REGISTRATION OR AN OPINION OF COUNSEL REASONABLY SATISFACTORY TO THE
         CORPORATION AND ITS COUNSEL THAT SUCH REGISTRATION IS NOT REQUIRED.

         THIS SECURITY IS SUBJECT TO CERTAIN RESTRICTIONS UPON TRANSFER,
         INCLUDING BUT NOT LIMITED TO A RIGHT OF FIRST OFFER ON BEHALF OF THE
         COMPANY, AS SET FORTH IN AN AGREEMENT BETWEEN THE COMPANY AND THE
         STOCKHOLDER, A COPY OF WHICH IS ON FILE WITH THE SECRETARY OF THE
         COMPANY.

         4.3      RESTRICTIONS ON TRANSFER.

                  4.3.1 RIGHT OF FIRST REFUSAL. Except as provided herein, the
Holder hereby understands, acknowledges and agrees that the Warrant may not be
sold or otherwise transferred without the Company's prior written consent.
Before the Warrant may be sold or otherwise transferred (including without
limitation a transfer by gift or operation of law) (the "OFFERED SECURITIES"),
the Company and/or its assignee(s) will have a right of first refusal to
purchase the Warrant to be sold or transferred on the terms and conditions set
forth in this Section 4.3.1 (the "RIGHT OF FIRST REFUSAL").


                                      4
<PAGE>


                        4.3.1.1 NOTICE OF PROPOSED TRANSFER. The Holder of
the Offered Securities will deliver to the Company a written notice (the
"TRANSFER NOTICE") stating: (i) the Holder's bona fide intention to sell or
otherwise transfer the Offered Securities; (ii) the name and address of each
proposed purchaser or other transferee (the "PROPOSED TRANSFEREE"); (iii) the
number or portion of such Offered Securities to be transferred to each Proposed
Transferee; (iv) the bona fide cash price or other consideration for which the
Holder proposes to transfer the Offered Securities (the "OFFERED PRICE"); and
(v) that the Holder acknowledges this Transfer Notice is an offer to sell the
Offered Securities to the Company pursuant to the Company's Right of First
Refusal at the Offered Price as provided for in this Warrant.

                        4.3.1.2 EXERCISE OF RIGHT OF FIRST REFUSAL. At any
time within thirty (30) days after the date of the Transfer Notice, the Company
may, by giving written notice to the Holder, elect to purchase all (or, with the
consent of the Holder, less than all) the Offered Securities proposed to be
transferred to any one or more of the Proposed Transferees named in the Transfer
Notice, at the purchase price determined in accordance with Subsection 4.3.1.3
below.

                        4.3.1.3 PURCHASE PRICE. The purchase price for the
Offered Securities purchased under this Section will be the Offered Price,
provided that if the Offered Price consists of no legal consideration (as, for
example, in the case of a transfer by gift), the purchase price will be the fair
market value of the Offered Securities as determined in accordance with Section
1.6 hereof. If the Offered Price includes consideration other than cash, then
the value of the non-cash consideration, as determined in good faith by the
Company's Board of Directors, will conclusively be deemed to be the cash
equivalent value of such non-cash consideration.

                           4.3.1.4 PAYMENT. Payment of the purchase price for
the Offered Securities will be payable, at the option of the Company, as
applicable, by check, by wire transfer or by cancellation of all or a portion of
any outstanding indebtedness owed by the Holder to the Company (or to such
assignee, in the case of a purchase of Offered Securities by such assignee) or
by any combination thereof. The purchase price will be paid without interest
within three (3) business days after the Company's election to exercise its
Right of First Refusal.

                           4.3.1.5 HOLDER'S RIGHT TO TRANSFER. If the Company
has not elected to exercise its Rights of First Refusal as provided in Section
4.3.1.2 or Holder has not consented to the purchase of less than all of the
Offered Securities proposed in the Transfer Notice to be transferred to a given
Proposed Transferee by the Company as provided in this Section, then the Holder
may sell or otherwise transfer all such Offered Securities to each Proposed
Transferee at the Offered Price or at a higher price (and if Holder consented to
the purchase of less than all the Offered Securities proposed in the Transfer
Notice to be transferred to a given Proposed Transferee by the Company as
provided in this Section, then the Holder may sell or otherwise transfer any
remaining Offered Securities to each Proposed Transferee at the Offered Price or
at a higher price), provided that (i) such sale or other transfer is consummated
within one hundred twenty (120) days after the date of the Transfer Notice and
(ii) any such sale or other transfer is effected in compliance with all
applicable securities laws. If the Offered Securities described in the Transfer
Notice are not transferred to each Proposed Transferee within such one hundred
twenty (120) day period, then a new Transfer Notice must be given to the
Company, pursuant to which the Company will again be offered the Right of First
Refusal before the Warrant may be sold or otherwise transferred.

                           4.3.1.6 EXEMPT TRANSFERS. Notwithstanding anything to
the contrary in this Section, the following transfers of the Warrant will be
exempt from the Right of First Refusal: (i) any transfer of the Warrant made
pursuant to a statutory merger or statutory consolidation of the Company with or
into another corporation or corporations (except that the Right of First Refusal
will continue to apply thereafter to the Warrant, in which case the surviving
corporation of such merger or consolidation shall succeed to the rights of the
Company under this Section unless the agreement of merger or consolidation
expressly otherwise provides); (ii) any transfer of the Warrant pursuant to the
winding up and dissolution of the Company; or (iii) any transfer of the Warrant
to any wholly owned subsidiary of Holder.

                           4.3.1.7 TERMINATION OF RIGHT OF FIRST REFUSAL. The
Right of First Refusal will terminate as to the Warrant on the first to occur of
the following: (i) the Expiration Date of this Warrant, or (ii) the effective
date of the registration of the Shares by the Company under the Act and
applicable state securities law, or (iii) the date of expiration of any
statutory holding period applicable to the Shares as required by Rule 144 and
any applicable state exemption from registration.


                                      5
<PAGE>

                           4.3.1.8 ENCUMBRANCES ON THE WARRANT. Holder may grant
a lien or security interest in, or pledge, hypothecate or encumber the Warrant
only if each party to whom such lien or security interest is granted, or to whom
such pledge, hypothecation or other encumbrance is made, agrees in a writing
satisfactory to the Company that: (i) such lien, security interest, pledge,
hypothecation or encumbrance will not apply to the Warrant after they are
acquired by the Company and/or its assignees under this Section; and (ii) the
provisions of this Section will continue to apply to the Warrant in the hands of
such party and any transferee of such party. Purchaser may not grant a lien or
security interest in, or pledge, hypothecate or encumber any part of this
Warrant.

                  4.3.2 SECURITIES LAWS. This Warrant and the Shares issuable
upon exercise of this Warrant may not be transferred or assigned in whole or in
part without compliance with applicable federal and state securities laws by the
transferor and the transferee (including, without limitation, the delivery of
investment representation letters and legal opinions reasonably satisfactory to
the Company, as reasonably requested by the Company). If, subject to the
provisions of this Section 4.3, the Holder is allowed to transfer this Warrant
or the Shares issuable upon exercise of this Warrant (or the securities
issuable, directly or indirectly, upon conversion of the Shares, if any), the
Company shall not require Holder to provide an opinion of counsel if there is no
material question as to the availability of current information as referenced in
Rule 144(c), Holder represents that it has complied with Rule 144(d) and (e) in
reasonable detail, the selling broker represents that it has complied with Rule
144(f), and the Company is provided with a copy of Holder's notice of proposed
sale and/or transfer.

         4.4      REGISTRATION.

                  4.4.1 REGISTRATION STATEMENT ON FORM S-3. For use in the sale
of up to 25 percent (25%) of the Shares (the "UNRESTRICTED SHARES"), within 30
days of the Issue Date, the Company will prepare and file with the Securities
and Exchange Commission ("SEC") a registration statement on Form S-3 (or such
other form that the Company may be eligible to use) relating to the sale of the
Unrestricted Shares by Holder from time to time (the "REGISTRATION STATEMENT"),
and use its reasonable best efforts, subject to receipt of necessary information
from Holder, to cause such Registration Statement to be declared effective by
the SEC as soon as is practicable after the SEC has completed its review
process. The Company agrees to use its reasonable best efforts to keep such
Registration Statement effective until twelve 12 months after the issue date.
The Company shall file all reports required to be filed by the Company with the
SEC in a timely manner and take all other necessary action so as to maintain
such eligibility for the use of Form S-3 (or its successor or equivalent).
Notwithstanding the foregoing, following the effectiveness of the Registration
Statement, the Company may, at any time, suspend the effectiveness of the
Registration Statement (a "SUSPENSION PERIOD"), by giving written notice to
Holder, if the Company shall have determined that the Company may be required to
disclose, update, correct or provide any material corporate development or
information. Holder agrees that, upon receipt of any notice from the Company of
a Suspension Period, Holder will not sell any Unrestricted Shares pursuant to
the Registration Statement until (i) Holder is advised in writing by the Company
that the use of the applicable prospectus may be resumed, (ii) Holder has
received copies of any additional or supplemental or amended prospectus, if
applicable, and (iii) Holder has received copies of any additional or
supplemental filings which are incorporated or deemed to be incorporated by
reference in such prospectus. The Company will use its reasonable best efforts
to ensure that the use of the Registration Statement may be resumed as soon as
reasonably practicable.

                           4.4.1.1 PUT RIGHT. The first time the Holder wishes
to sell any or all of the Unrestricted Shares pursuant to the Registration
Statement, it shall notify the Company in writing (the "SALE NOTICE"). The Sale
Notice may not be given by the Holder any sooner than 90 days after the Issue
Date. If upon receipt of the Sale Notice, the Registration Statement for the
Unrestricted Shares has not been declared effective for any reason other than
for the Holder's failure to provide necessary information for such Registration
Statement, then the Company shall immediately notify the Holder that such
Registration Statement has not been declared effective (the "COMPANY
REGISTRATION NOTICE") and the Holder will have the right to require the Company
to purchase all such Unrestricted Shares subject to the terms and conditions
hereof (the "PUT RIGHT"). Upon receipt of the Company Registration Notice, the
Holder must notify the Company within three (3) business days as to whether it
wishes to exercise the Put Right (the "PUT EXERCISE NOTICE"). Upon receipt of
the Put Exercise Notice, the Company shall purchase and the Holder shall sell to
the Company, free and clear of any encumbrances, all such Unrestricted Shares by
the Company's paying for each and every share of the Unrestricted Shares subject
to the Put Right an amount equal to the closing price of a share of the
Company's Common Stock as quoted on Nasdaq or any other exchange on which the
Common Stock of the Company is listed as of the date of the receipt of the Sale
Notice by the Company. The closing of the Put Right exercise shall occur within
three (3) business days of Company's receipt of the Put Exercise Notice. The Put
Right shall expire on the date the Registration Statement first becomes
effective.


                                      6
<PAGE>

                  4.4.2 DELIVERY OF PROSPECTUS. The Company shall furnish to
Holder promptly after the Registration Statement is prepared and publicly
distributed, filed with the SEC, or received by the Company, one copy of the
Registration Statement and any amendment thereto, each preliminary prospectus
and prospectus and each amendment or supplement thereto. The Company shall
furnish to Holder such number of copies of prospectuses and preliminary
prospectuses in conformity with the requirements of the Securities Act, in order
to facilitate the public sale or other disposition of all or any of the
Unrestricted Shares by Holder; provided, however, that the obligation of the
Company to deliver copies of prospectuses or preliminary prospectuses to the
Holder shall be subject to the receipt by the Company of reasonable assurances
from Holder that Holder will comply with the applicable provisions of the
Securities Act and of such other securities or blue sky laws as may be
applicable in connection with any use of such prospectuses or preliminary
prospectuses. The Company shall bear all expenses incurred by the Company in
connection with the registration of the Unrestricted Shares pursuant to the
Registration Statement (but excluding underwriters' and brokers' discounts and
commissions), and the reasonable fees and disbursements (not to exceed $10,000
in the aggregate) of a single special counsel for Holder.

                  4.4.3 INFORMATION. It shall be a condition precedent to the
obligations of the Company to take any action pursuant to Section 4.4.1 that
Holder shall provide such information regarding itself, the Unrestricted Shares
held by them, the intended method of disposition of the Unrestricted Shares and
such other information as the Company may reasonably request to timely effect
the registration of the Unrestricted Shares.

                  4.4.4 INDEMNIFICATION. For the purpose of this Section 4.4.4,
the term "Registration Statement" shall include any final prospectus, exhibit,
supplement or amendment included in or relating to the Registration Statement
referred to in Section 4.4.1.

                        (a) The Company agrees to indemnify and hold harmless
Holder, each of its directors and officers, any underwriters (as defined in the
Securities Act) for Holder and each person, if any, who controls Holder within
the meaning of the Securities Act, against any losses, claims, damages,
liabilities or expenses to which Holder or such officer or director, underwriter
or controlling person may become subject, under the Securities Act, the
Securities Exchange Act of 1934, as amended (the "EXCHANGE ACT"), or any other
federal or state statutory law or regulation, or at common law or otherwise
(including in settlement of any litigation, if such settlement is effected with
the written consent of the Company), insofar as such losses, claims, damages,
liabilities or expenses (or actions in respect thereof as contemplated below)
arise out of or are based upon (i) any untrue statement or alleged untrue
statement of any material fact contained in the Registration Statement,
including the prospectus, financial statements and schedules, and all other
documents filed as a part thereof or incorporated by reference therein, as
amended at the time of effectiveness of the Registration Statement, including
any information deemed to be a part thereof as of the time of effectiveness
pursuant to paragraph (b) of Rule 430A,or pursuant to Rule 434, of the Rules and
Regulations, or the prospectus, in the form first filed with the SEC pursuant to
Rule 424(b) of the Regulations, or filed as part of the Registration Statement
at the time of effectiveness if no Rule 424(b) filing is required (the
"PROSPECTUS"), or any amendment or supplement thereto, (ii) the omission or
alleged omission to state in any of them a material fact required to be stated
therein or necessary to make the statements in any of them not misleading, or
(iii) any violation or alleged violation by the Company of the Securities Act,
the Exchange Act or any federal or state securities law in connection with the
offering covered by such registration statement (the matters in the foregoing
clauses (i) through (iii) being, collectively, "VIOLATIONS"), and will reimburse
Holder and each such officer or director, underwriter or controlling person for
any legal and other expenses as such expenses are reasonably incurred by Holder
or such controlling person in connection with investigating, defending,
settling, compromising or paying any such loss, claim, damage, liability,
expense or action; provided, however, the indemnity agreement contained in this
Section 4.4.4(a) shall not apply to amounts paid in settlement of any such loss,
claim, damage, liability, expense or action if such settlement is effected
without the consent of the Company (which consent shall not be unreasonably
withheld or delayed) and provided, further, that the Company will not be liable
in any such case to the extent that any such loss, claim, damage, liability or
expense arises out of or is based upon an untrue statement or alleged untrue
statement or omission or alleged omission made in the Registration Statement,
the Prospectus or any amendment or supplement thereto in reliance upon and in
conformity with (i) written information furnished to the Company by or on behalf
of Holder expressly for use therein or (ii) the failure of Holder to comply with
the covenants and agreements contained in this Warrant respecting the sale of
the Unrestricted Shares, the inaccuracy of any representations made by Holder
herein or any statement or omission in any Prospectus that is corrected in any
subsequent Prospectus that was delivered to Holder prior to the pertinent sale
or sales by Holder.

                        (b) Holder will indemnify and hold harmless the
Company, each of its directors, each of its officers who signed the Registration
Statement and each person, if any, who controls the Company within the meaning
of the Securities Act, against any losses, claims, damages, liabilities or
expenses to which the Company,


                                      7
<PAGE>

each of its directors, each of its officers who signed the Registration
Statement or controlling person may become subject, under the Securities Act,
the Exchange Act, or any other federal or state statutory law or regulation,
or at common law or otherwise (including in settlement of any litigation, if
such settlement is effected with the written consent of Holder) insofar as
such losses, claims, damages, liabilities or expenses (or actions in respect
thereof as contemplated below) arise out of or are based upon any Violation,
in each case to the extent, but only to the extent, that such Violation
occurs in reliance upon and in conformity with written information furnished
to the Company by or on behalf of any Holder expressly for use therein, and
will reimburse the Company, each of its directors, each of its officers who
signed the Registration Statement or controlling person for any legal and
other expense reasonably incurred by the Company, each of its directors, each
of its officers who signed the Registration Statement or controlling person
in connection with investigating, defending, settling, compromising or paying
any such loss, claim, damage, liability, expense or action; provided,
however, the indemnity agreement contained in this Section 4.4.4(b) shall not
apply to amounts paid in settlement of any such loss, claim, damage,
liability, expense or action if such settlement is effected without the
consent of the Holder (which consent shall not be unreasonably withheld or
delayed). Notwithstanding the foregoing, in no event shall any indemnity
under this Section 4.4.4(b) exceed the proceeds from the offering of Shares
made under the Registration Statement.

                        (c) Promptly after receipt by an indemnified party
under this Section 4.4.4 of notice of the commencement of any action, such
indemnified party will, if a claim in respect thereof is to be made against an
indemnifying party under this Section 4.4.4, notify the indemnifying party in
writing of the commencement thereof; but the omission so to notify the
indemnifying party will not relieve it from any liability which it may have to
any indemnified party for contribution or otherwise than under the indemnity
agreement contained in this Section 4.4.4 or to the extent it is not prejudiced
as a proximate result of such failure. In case any such action is brought
against any indemnified party and such indemnified party seeks or intends to
seek indemnity from an indemnifying party, the indemnifying party will be
entitled to participate in, and, to the extent that it may wish, jointly with
all other indemnifying parties similarly notified, to assume the defense thereof
with counsel reasonably satisfactory to such indemnified party; provided,
however, if the defendants in any such action include both the indemnified party
and the indemnifying party and the indemnified party shall have reasonably
concluded that there may be a conflict between the positions of the indemnifying
party and the indemnified party in conducting the defense of any such action or
that there may be legal defenses available to it and/or other indemnified
parties which are different from or additional to those available to the
indemnifying party, the indemnified party or parties shall have the right to
select separate counsel reasonably acceptable to the indemnifying party to
assume such legal defenses and to otherwise participate in the defense of such
action on behalf of such indemnified party or parties. Upon receipt of notice
from the indemnifying party to such indemnified party of its election so to
assume the defense of such action and approval by the indemnified party of
counsel, the indemnifying party will not be liable to such indemnified party
under this Section 4.4.4 for any legal or other expenses subsequently incurred
by such indemnified party in connection with the defense thereof unless (i) the
indemnified party shall have employed such counsel in connection with the
assumption of legal defenses in accordance with the proviso to the preceding
sentence (it being understood, however, that the indemnifying party shall not be
liable for the expenses of more than one separate counsel, approved by such
indemnifying party in the case of paragraph (a), representing the indemnified
parties who are parties to such action) or (ii) the indemnified party shall not
have employed counsel reasonably satisfactory to the indemnified party to
represent the indemnified party within a reasonable time after notice of
commencement of action, in each of which cases the fees and expenses of counsel
shall be at the expense of the indemnifying party.

                        (d) The foregoing indemnity agreements of the Company
and Holder are subject to the condition that, insofar as they relate to the
bases for any losses, claims, damages, liabilities or expenses contemplated in
Section 4.4.4(a) arising out of the preparation and filing of the preliminary
prospectus but eliminated or remedied in the amended prospectus on file with the
SEC at the time the registration statement in question becomes effective or the
amended prospectus filed with the SEC pursuant to SEC Rule 424(b) (the "FINAL
PROSPECTUS"), such indemnity agreement shall not inure to the benefit of any
person if a copy of the Final Prospectus was furnished to the indemnified party
and was not furnished to the person asserting the loss, liability, claim or
damage at or prior to the time such action is required by the Securities Act.

         4.5 TRANSFER PROCEDURE. If, subject to the provisions of Section 4.3,
Holder is allowed to transfer all or part of this Warrant, Holder shall give the
Company a written notice of the portion of the Warrant being transferred, such
notice setting forth the name, address and taxpayer identification number of the
transferee, and, together with such notice, Holder shall surrender this Warrant
to the Company for reissuance to the transferee (and to the new Warrant Holder
for any remaining Shares, if applicable). As a condition to sale, transfer or
assignment (other than pursuant to the Registration Statement under Section 4.4)
of this Warrant and the Shares issuable upon exercise of this Warrant, the
Holder shall confirm, acknowledge and agree to the representations, warranties
and agreements


                                      8
<PAGE>

forth in Section 4 hereof.


5.       GENERAL PROVISIONS.

         5.1 NOTICES. Any and all notices and Transfer Notices required or
permitted to be given to a party pursuant to the provisions of this Warrant will
be in writing and will be effective and deemed to provide such party sufficient
notice under this Warrant on the earliest of the following: (i) at the time of
personal delivery, if delivery is in person; (ii) at the time of transmission by
facsimile, addressed to the other party at its facsimile number specified herein
(or hereafter modified by subsequent notice to the parties hereto), with
confirmation of receipt made by both telephone and printed confirmation sheet
verifying successful transmission of the facsimile; (iii) one (1) business day
after deposit with an express overnight courier for United States deliveries, or
two (2) business days after such deposit for deliveries outside of the United
States, with proof of delivery from the courier requested; or (iv) three (3)
business days after deposit in the United States mail by certified mail (return
receipt requested) for United States deliveries.

                  All notices for delivery outside the United States will be
sent by facsimile or by express courier. All notices not delivered personally or
by facsimile will be sent with postage and/or other charges prepaid and properly
addressed to the party to be notified at the address or facsimile number set
forth below the signature lines to this Warrant, or at such other address or
facsimile number as such other party may designate by one of the indicated means
of notice herein to the other parties hereto. Notices to the Company will be
marked "Attention: President". Notices by facsimile shall be machine verified as
received.

         5.2 GOVERNING LAW. This Warrant will be governed by and construed in
accordance with the laws of the State of California, without giving effect to
that body of laws pertaining to conflict of laws.

         5.3 FURTHER ASSURANCES. The parties agree to execute such further
documents and instruments and to take such further actions as may be reasonably
necessary to carry out the purposes and intent of this Warrant.

         5.4 TITLES AND HEADINGS. The titles, captions and headings of this
Warrant are included for ease of reference only and will be disregarded in
interpreting or construing this Warrant. Unless otherwise specifically stated,
all references herein to "sections" and "exhibits" will mean "sections" and
"exhibits" to this Warrant.

         5.5 COUNTERPARTS. This Warrant may be executed in any number of
counterparts, each of which when so executed and delivered will be deemed an
original, and all of which together shall constitute one and the same agreement.

         5.6 SEVERABILITY. If any provision of this Warrant is determined by any
court or arbitrator of competent jurisdiction to be invalid, illegal or
unenforceable in any respect, such provision will be enforced to the maximum
extent possible given the intent of the parties hereto. If such clause or
provision cannot be so enforced, such provision shall be stricken from this
Warrant and the remainder of this Warrant shall be enforced as if such invalid,
illegal or unenforceable clause or provision had (to the extent not enforceable)
never been contained in this Warrant. Notwithstanding the forgoing, if the value
of this Warrant based upon the substantial benefit of the bargain for any party
is materially impaired, which determination as made by the presiding court or
arbitrator of competent jurisdiction shall be binding, then both parties agree
to substitute such provision(s) through good faith negotiations.

         5.7 FACSIMILE SIGNATURES. This Warrant may be executed and delivered by
facsimile and upon such delivery the facsimile signature will be deemed to have
the same effect as if the original signature had been delivered to the other
party. The original signature copy shall be delivered to the other party by
express overnight delivery. The failure to deliver the original signature copy
and/or the nonreceipt of the original signature copy shall have no effect upon
the binding and enforceable nature of this Warrant.

         5.8 AMENDMENT AND WAIVERS. This Warrant may be amended only by a
written agreement executed by each of the parties hereto. No amendment of or
waiver of, or modification of any obligation under this Warrant will be
enforceable unless set forth in a writing signed by the party against which
enforcement is sought. Any amendment effected in accordance with this Section
5.8 will be binding upon all parties hereto and each of their respective
successors and assigns. No delay or failure to require performance of any
provision of this Warrant shall constitute a waiver of that provision as to that
or any other instance. No waiver granted under this Warrant as to any


                                      9
<PAGE>

one provision herein shall constitute a subsequent waiver of such provision
or of any other provision herein, nor shall it constitute the waiver of any
performance other than the actual performance specifically waived.

         5.9 ENTIRE AGREEMENT. This Warrant and the documents referred to
herein, including but not limited to the Development and Marketing Agreement
between Company and Holder dated of even date herewith, constitute the entire
agreement and understanding of the parties with respect to the subject matter of
this Warrant, and supersede all prior understandings and agreements, whether
oral or written, between or among the parties hereto with respect to the
specific subject matter hereof.



WARRANT HOLDER:                             COMPANY:


/s/ William P. Sullivan                     /s/ Robert L. Schultz, Jr.
--------------------------------            -------------------------------
AGILENT TECHNOLOGIES, INC.                  ADAPTEC, INC.

Name: William P. Sullivan                   Name: Robert L. Schultz, Jr.
     ---------------------------                 --------------------------

Title: Senior Vice President and            Title: Chief Operating Officer
       General Manager                            -------------------------
      --------------------------



                                      10
<PAGE>

                                    EXHIBIT A

                               NOTICE OF EXERCISE

                  (TO BE SIGNED ONLY UPON EXERCISE OF WARRANT)

1.  PLEASE MARK ONE OF THE FOLLOWING:

[ ] 1.1 CASH EXERCISE ELECTION. The undersigned hereby elects to purchase
___________ shares of the Common Stock of ADAPTEC, INC., a Delaware corporation,
pursuant to the terms of the attached Warrant to Purchase Stock with an Issue
Date of January 17, 2000 (the "WARRANT"), and the Undersigned tenders herewith
payment of the total purchase price of such shares in full, pursuant to a check
or wire transfer, in the amount of $__________.


OR


[ ] 1.2 NET EXERCISE ELECTION. The undersigned Holder elects to convert all or
part of the Warrant into shares of stock by net exercise election pursuant to
Section 1.6 of the Warrant. This conversion is exercised with respect to
__________ shares of Common Stock of ADAPTEC, INC. covered by the Warrant.


         2. Please issue a certificate or certificates representing said shares
in the name of the undersigned. The undersigned represents that it is acquiring
the shares solely for its own account and not as a nominee for any other party
and not with a view toward the resale or distribution thereof except in
compliance with applicable securities laws and hereby confirms and agrees to the
representations, warranties and agreements that are set forth in Section 4 of
the attached Warrant.



                                          ____________________________________
                                          (Name)

                                          ____________________________________
                                          ____________________________________
                                          ____________________________________
                                          Address


                                          ____________________________________
                                          (Signature of Holder)


                                      1
<PAGE>

                                  AMENDMENT
                                     OF
                          WARRANT TO PURCHASE STOCK
                                     OF
                                ADAPTEC, INC.

     This Amendment is made effective as of February 14, 2000 between
Adaptec, Inc. (the "COMPANY") and Agilent Technologies, Inc., the "HOLDER"
(as defined in the Warrant) of that certain Warrant to Purchase Stock, Issue
Date of January 17, 2000, providing for the purchase of 464,000 shares of the
Common Stock of the Company at an Initial Exercise Price of $62.25 per share
(the "WARRANT").  Capitalized terms used herein and not otherwise defined
shall have the meanings ascribed to them in the Warrant.

                                   RECITAL

     WHEREAS, the Company and the undersigned Holder desire to amend the
Warrant to adequately reflect their current understanding of their rights and
obligations under the Warrant.

                                  AGREEMENT

     NOW THEREFORE, pursuant to Section 5.8 of the Warrant, the Company and the
Holder hereby agree as follows:

     1.  To amend the Warrant so that the portion of Section 4.4.1 of the
     Warrant which reads "within 30 days of the Issue Date" is deleted and is
     replaced by "as soon as reasonably possible but in no event later than
     51 days of the Issue Date"; and

     2.  That all other provisions of the Warrant shall remain in full force
     and effect.

     This Amendment may be executed in any number of counterparts, each of
which shall be deemed an original and enforceable against the parties
actually executing such counterpart, and all of which together shall
constitute one instrument.


                                      1
<PAGE>

     This Amendment is executed and is effective as of the date first set
forth above.


COMPANY:

ADAPTEC, INC.

By: /s/ Andrew J. Brown
   ----------------------------------

Name: Andrew J. Brown
     --------------------------------

Title: Vice President, Finance and Chief Financial Officer
     -----------------------------------------------------


HOLDER:

AGILENT TECHNOLOGIES, INC.

By: /s/ William P. Sullivan
   ----------------------------------

Name: William P. Sullivan
     --------------------------------

Title: Senior Vice President and General Manager
     -----------------------------------------------------


1002629




[SIGNATURE PAGE TO THE AMENDMENT OF WARRANT TO PURCHASE STOCK OF ADAPTEC, INC.]


                                      2