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                                                               Exhibit 4.1

                                  ADAPTEC, INC.

                          REGISTRATION RIGHTS AGREEMENT

         This Registration Rights Agreement (the "AGREEMENT") is made
effective as of March 10, 2000 (the "EFFECTIVE DATE"), by and among Adaptec,
Inc., a Delaware corporation (the "PARENT"), Wild File, Inc., a Delaware
corporation (the "COMPANY"), and those persons whose signatures appear on the
signature page hereto (each a "STOCKHOLDER" and collectively, the
"STOCKHOLDERS").

                                    RECITALS

         A.  The Company, Parent, Snowfall Acquisition Corporation, a
Delaware corporation ("SUB"), and certain others, are parties to the
Agreement and Plan of Reorganization dated March 3, 2000 (together with the
exhibits and schedules thereto, the "MERGER AGREEMENT"), pursuant to which
the Company shall be merged with and into Sub, the separate corporate
existence of the Company shall cease and Sub shall continue as the surviving
corporation and as a wholly-owned subsidiary of Parent.

         B.  Pursuant to the Merger Agreement, among other things, the
Stockholders shall have the right to receive the shares of common stock of
Parent (the "SHARES") in exchange for outstanding shares of Company capital
stock.

                                    AGREEMENT

         NOW, THEREFORE, in consideration of the mutual promises and
covenants hereinafter set forth, all parties hereto agree as follows:

         1.   CERTAIN DEFINITIONS.  As used in this Agreement, the following
terms shall have the following respective meanings:

         "BLACK-OUT PERIOD" means any period during which executive officers
and directors of Parent are generally prohibited from engaging in trades in
Parent's securities pursuant to Parent's Insider Trading Policy.

         "COMMISSION" means the Securities and Exchange Commission or any
other Federal agency at the time administering the Securities Act.

         "EXCHANGE ACT" means the Securities Exchange Act of 1934, as
amended, or any similar Federal rule or statute and the rules and regulations
of the Commission thereunder, all as the same shall be in effect at the time.

         "HOLDER" means any of the Stockholders, for so long as such person
holds any Registrable Securities, or any person holding Registrable
Securities to whom the rights under this Agreement have been transferred in
accordance with Section 11 hereof.

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         "INSIDER TRADING POLICY" means the policy adopted by Parent's Board
of Directors, as such may be amended from time to time, relating to
transactions in Parent's securities by Parent's executive officers and
directors.

         "PERMITTED WINDOW" means the period during which a Holder entitled
to sell Registrable Securities pursuant to a registration statement under
Section 5(a) of this Agreement shall be permitted to sell Registrable
Securities pursuant to such a registration. Except as otherwise set forth in
this Agreement, a Permitted Window shall (i) commence immediately after the
end of a Black-Out Period, and shall (ii) terminate upon the commencement of
a Black-Out Period, unless Holder receives notice from Parent to the contrary
in accordance with Section 5(b)(iii).

         "REGISTRABLE SECURITIES" means the Shares and any Common Stock of
Parent issued to the Stockholders in the Merger, other than shares held in
escrow pursuant to ARTICLE VII of the Merger Agreement, or issuable in
respect thereof upon any conversion, stock split, stock dividend,
recapitalization, merger or other reorganization; PROVIDED, HOWEVER, that
securities shall only be treated as Registrable Securities if and so long as
they have not been registered or sold to or through a broker or dealer or
underwriter in a public distribution or a public securities transaction.

         "REGISTER," "REGISTERED" and "REGISTRATION" refer to a registration
effected by preparing and filing a registration statement in compliance with
the Securities Act, and the declaration or ordering of the effectiveness of
such registration statement.

         "REGISTRATION EXPENSES" means all expenses, except Selling Expenses,
incurred by Parent in complying with Section 5 hereof, including without
limitation, all registration, qualification and filing fees, printing
expenses, escrow fees, fees and disbursements of counsel for Parent, blue sky
fees and expenses, the expense of any special audits incident to or required
by any such registration (but excluding the compensation of regular employees
of Parent which shall be paid in any event by Parent).

         "RESTRICTED SECURITIES" means the securities of Parent required to
bear a legend as described in Section 3 hereof.

         "SECURITIES ACT" means the Securities Act of 1933, as amended, or
any similar Federal rule or statute and the rules and regulations of the
Commission thereunder, all as the same shall be in effect at the time.

         "SELLING EXPENSES" means all underwriting discounts, selling
commissions and stock transfer taxes applicable to the securities registered by
the Holders and all fees and disbursements of counsel for any Holder.

         2.   RESTRICTIONS ON TRANSFERABILITY. The Restricted Securities and
any other securities issued in respect of such securities upon any stock
split, stock dividend, recapitalization, merger or other reorganization,
shall not be sold, assigned, transferred or pledged except upon the
conditions specified in this Agreement, which conditions are intended to
ensure compliance with the provisions of the Securities Act. Each Holder or
transferee will cause any proposed purchaser, assignee,

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transferee, or pledgee of any such securities held by the Holder or
transferee to agree to take and hold such securities subject to the
restrictions and upon the conditions specified in this Agreement, including
without limitation the restrictions set forth in Section 4.

         3.   RESTRICTIVE LEGEND. Each certificate representing the Shares or
any other securities issued in respect of such securities upon any stock
split, stock dividend, recapitalization, merger or other reorganization shall
be stamped or otherwise imprinted with the following legends:

              THE SECURITIES REPRESENTED HEREBY HAVE BEEN ACQUIRED FOR
              INVESTMENT AND HAVE NOT BEEN REGISTERED UNDER THE SECURITIES
              ACT OF 1933, AS AMENDED. SUCH SECURITIES MAY NOT BE TRANSFERRED
              UNLESS A REGISTRATION STATEMENT UNDER SAID ACT IS IN EFFECT AS
              TO SUCH TRANSFER OR, IN THE OPINION OF COUNSEL SATISFACTORY TO
              THE ISSUER, SUCH TRANSFER MAY BE MADE WITHOUT REGISTRATION
              UNDER SAID ACT

Each Holder consents to Parent making a notation on its records and giving
instructions to any transfer agent of its capital stock in order to implement
the restrictions on transfer established in this Agreement and the Purchase
Agreement.

         4.   NOTICE OF PROPOSED TRANSFERS. The holder of each certificate
representing Restricted Securities by acceptance thereof agrees to comply in
all respects with the provisions of this Section 4. Without in any way
limiting the immediately preceding sentence or the provisions of Section 2,
no sale, assignment, transfer or pledge (other than (i) a sale made pursuant
to a registration statement filed under the Securities Act and declared
effective by the Commission or (ii) a sale made in accordance with the
applicable provisions of Rule 144) of Restricted Securities shall be made by
any holder thereof to any person unless such person shall first agree in
writing to be bound by the restrictions of this Agreement, including without
limitation this Section 4. Prior to any proposed sale, assignment, transfer
or pledge of any Restricted Securities, unless there is in effect a
registration statement under the Securities Act covering the proposed
transfer, the holder thereof shall give written notice to Parent of such
holder's intention to effect such transfer, sale, assignment or pledge. Each
such notice shall describe the manner and circumstances of the proposed
transfer, sale, assignment or pledge in sufficient detail, and, if requested
by Parent, the holder shall also provide, at such holder's expense, a written
opinion of legal counsel (who shall be, and whose legal opinion shall be,
reasonably satisfactory to Parent) addressed to Parent, to the effect that
the proposed transfer of the Restricted Securities may be effected without
registration under the Securities Act and under applicable state securities
laws and regulations. Upon delivery to Parent of such notice and, if
required, such opinion, the holder of such Restricted Securities shall be
entitled to transfer such Restricted Securities in accordance with the terms
of such notice. Parent agrees that it shall not request such an opinion of
counsel with respect to (i) a transfer not involving a change in beneficial
ownership, (ii) a transaction involving the transfer without consideration of
Restricted Securities by an individual holder during such holder's lifetime
by way of gift or on death by will or the laws of descent and distribution.
Each certificate evidencing the Restricted Securities transferred

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as above provided shall bear, except if such transfer is made pursuant to
Rule 144, the appropriate restrictive legend set forth in Section 3 above,
except that such certificate shall not bear such restrictive legend if, in
the opinion of counsel for such holder and counsel for Parent, such legend is
not required in order to establish or ensure compliance with any provision of
the Securities Act.

         5.   REGISTRATION ON FORM S-3.

              (a)  REGISTRATION. Parent shall use its commercially reasonable
efforts to cause a registration statement on Form S-3 (or any successor form,
a "FORM S-3") covering all Registrable Securities to be filed no later than
May 15, 2000, and declared effective as soon as practicable thereafter
provided that such date does not occur within any Black-Out Period and
provided further that the financial statements contained in Parent's most
recent quarterly or annual report on Form 10-Q and Form 10-K, respectively,
are not of a date 135 days or more on or prior to the 90th day following the
Closing Date, in which case, Parent shall use its commercially reasonable
efforts to cause such registration statement to be filed within ten (10) days
after Parent's next quarterly or annual report on Form 10-Q or Form 10-K, as
the case may be, is filed and declared effective as soon as practicable
thereafter. Parent shall use its commercially reasonable efforts to keep such
registration statement effective until the first anniversary of the date of
this Agreement, or such earlier date upon which no Holder holds any
Registrable Securities. Upon receipt of a notice from any Holder that such
Holder intends to sell Registrable Securities during a Permitted Window,
Parent shall, prior to the commencement of the Permitted Window, inform the
other Holders of the commencement of the Permitted Window. Parent shall
notify each of the Holders of the termination of a Permitted Window no later
than the time Parent notifies its executive officers and directors of the
corresponding Black-Out Period; PROVIDED, HOWEVER, that Parent need not
notify the Holders of regularly scheduled Black-Out Periods relating to the
closing of Parent's fiscal quarters, which periods commence on the fifteenth
day prior to the end of the last month of each fiscal quarter and terminate
twenty-four hours after Parent publicly announces its results for such
quarters.

              (b)  LIMITATIONS ON REGISTRATION AND SALE OF REGISTRABLE
SECURITIES. Notwithstanding anything in this Agreement to the contrary,
Parent's obligations and the Holders' rights under this Section 5 are subject
to the limitations and qualifications set forth below, which may be waived in
writing by Parent.

                   (i) Parent shall have no obligation to keep effective a
registration statement hereunder following such time as each Holder is
eligible to sell all of its Registrable Securities in a three month period
under the applicable provisions of Rule 144.

                   (ii) The Holders will sell Registrable Securities pursuant
to a registration effected hereunder only during a Permitted Window.

                   (iii) If Parent furnishes to the Holders a certificate
signed by the President or Chief Financial Officer of Parent stating that, in
the good faith judgment of the Board of Directors of Parent, it would be
seriously detrimental to Parent for a Form S-3 registration to be effected,
or a Permitted Window to be in effect, due to (A) the existence of a material
development or potential material development involving Parent which Parent
would be obligated to disclose in the

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prospectus contained in the Form S-3 registration statement, which disclosure
would in the good faith judgment of the Board of Directors be premature or
otherwise inadvisable or (B) the existence of other facts or circumstances as
a result of which the prospectus contained or to be contained in the Form S-3
registration statement includes or would include an untrue statement of a
material fact or omits or would omit to state a material fact required to be
stated therein or necessary to make the statements therein not misleading in
light of the circumstances under which they were made or then existing,
Parent may defer the filing of the Form S-3 registration statement or delay
the commencement of a Permitted Window or may effect an early termination of
a Permitted Window that has commenced, as the case may be. Parent may elect
to so defer, delay or terminate under clause (A) above only to the extent
that the event described in clause (A) also gives rise to a Black-Out Period
applicable to all of Parent's executive officers and directors under Parent's
Insider Trading Policy. If Parent elects to so defer, delay or terminate
under clause (B) above, Parent shall use its commercially reasonable efforts
to amend the registration statement or take such other action as may be
necessary to eliminate the situation described in clause (B) as soon as
practicable. Any Holder receiving any notice from Parent with respect to the
matters covered by this Section 5(b)(iii) shall keep the fact and content of
such notice, and the event or circumstances giving rise to such notice,
confidential.

                   (iv) The obligations of Parent hereunder are conditioned
upon its being eligible to register its securities on Form S-3 at the time
any such registration is otherwise required hereunder; provided, however that
Parent shall use its reasonable best efforts to remain eligible for use of
Form S-3 for the one-year period following the Effective Date; and provided
further that if after registration is accomplished on Form S-3 and prior to
the time that is one year following the Effective Date Parent is no longer
eligible to use Form S-3, subject to the provisions of this Section 5(b),
Parent shall undertake to continue the registration of the Registrable
Securities on another eligible form.

                   (v) Notwithstanding anything to the contrary in this
Agreement, Parent shall have no obligation to effect a registration
hereunder, and no Permitted Window will exist, with respect to Registrable
Securities that are subject to the escrow provisions of the Merger Agreement
(including any agreement which is an exhibit thereto) during the time that
such Registrable Securities are subject to such provisions and no Holder
shall sell any such Registrable Securities pursuant to a registration
hereunder, or pursuant to Rule 144, during any such period.

              (c)  REGISTRATION PROCEDURES. In connection with any
registration required under this Agreement, Parent shall take the actions set
forth below.

                   (i) Prior to filing any registration statement,
prospectus, amendment or supplement with the Commission in connection with
any registration hereunder, Parent shall furnish to one counsel selected by
the Holders of a majority of the Registrable Securities copies of such
documents.

                   (ii) Parent shall notify each Holder of any stop order
issued or threatened by the Commission and will take all reasonable actions
required to prevent the entry of such stop order or to remove it if entered.

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                   (iii) Parent shall comply with the provisions of the
Securities Act with respect to the disposition of all securities covered by a
registration statement filed pursuant to this Agreement with respect to the
disposition of all Registrable Securities covered by such registration
statement in accordance with the intended methods of disposition by the
Holders as set forth in such registration statement.

                   (iv) Parent shall furnish to each Holder and each
underwriter, if any, of Registrable Securities covered by a registration
statement filed pursuant to this Agreement such number of copies of such
registration statement, each amendment and supplement thereto (in each case
including all exhibits thereto), and the prospectus included in such
registration statement (including each preliminary prospectus), in conformity
with the requirements of the Securities Act, and such other documents as a
selling Holder may reasonably request in order to facilitate the disposition
of the Registrable Securities owned by such Holder. Such delivery of
documents shall be made by Parent within two (2) trading days of receipt of a
request therefor from a Holder.

                   (v) Parent shall use its best efforts to register or
qualify the Registrable Securities under the securities or "blue sky" laws of
each State of the United States of America as any of the Holders or
underwriters, if any, of the Registrable Securities covered by a registration
statement filed hereunder reasonably requests, and shall do any and all other
acts and things which may be reasonably necessary or advisable to enable each
selling Holder and each underwriter, if any, to consummate the disposition in
such States of the Registrable Securities owned by such selling Holders;
PROVIDED that Parent shall not be required to (A) qualify generally to do
business in any jurisdiction where it would not otherwise be required to
qualify but for this subsection (v), (B) subject itself to taxation in any
such jurisdiction or (C) consent to general service of process in any such
jurisdiction.

                   (vi) Parent shall immediately notify each Holder entitled
to sell Registrable Securities during a Permitted Window of the happening of
any event which comes to Parent's attention if, as a result of such event,
the prospectus included in the registration statement filed under this
Agreement contains any untrue statement of a material fact or omits to state
any material fact necessary to make the statements therein, in light of the
circumstances under which they were made, not misleading, and Parent shall
promptly prepare and furnish to each Holder and file with the Commission a
supplement or amendment to such prospectus so that such prospectus will no
longer contain any untrue statement of a material fact or omit to state any
material fact necessary to make the statements therein, in light of the
circumstances under which they were made, not misleading.

                   (vii) Parent shall take all such other reasonable and
customary actions as each Holder or the underwriters, if any, may reasonably
request in order to expedite or facilitate the disposition of the Registrable
Securities in accordance with the terms of this Agreement.

                   (viii) Parent shall make available for inspection by the
Holders, any underwriter participating in any disposition pursuant to a
registration statement filed under this Agreement, and any attorney,
accountant or other agent retained by such Holders or underwriters, all
financial and other records, pertinent corporate documents and properties of
Parent and its subsidiaries, as such person may reasonably request for the
purpose of confirming that such

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registration statement does not contain any untrue statement of a material
fact or omit to state any material fact necessary to make the statements
therein, in light of the circumstances under which they were made, not
misleading, provided that Parent obtains reasonably satisfactory assurances
that such information will be used solely for such purpose and will be held
in confidence (except to the extent that it is included in the registration
statement). Parent shall cause the officers, directors and employees of
Parent and each of its subsidiaries to supply such information and respond to
such inquiries as any Holder or underwriter may reasonably request or make
for the purpose of confirming that such registration statement does not
contain any untrue statement of a material fact or omit to state any material
fact necessary to make the statements therein, in light of the circumstances
under which they were made, not misleading, provided that Parent obtains
reasonably satisfactory assurances that such information will be used solely
for such purpose and will be held in confidence (except to the extent that it
is included in the registration statement).

         6.   OTHER REGISTRATION RIGHTS. The Holders acknowledge that certain
other stockholders of Parent may now or hereafter have registration rights,
and that such other stockholders may be entitled to sell their securities at
the same time, or pursuant to the same registration and underwriting, as the
Holders hereunder.

         7.   EXPENSES OF REGISTRATION. All Registration Expenses incurred in
connection with Parent's obligations hereunder shall be borne by Parent. All
Selling Expenses relating to securities proposed to be registered hereunder
and all other registration expenses shall be borne by the Holders of such
securities pro rata on the basis of the number of shares proposed to be sold
by each of them during the applicable Permitted Window; provided, however,
that Parent shall be obligated to pay up to an aggregate of $3,000 for the
legal fees relating to securities proposed to be registered hereunder and all
other registration expenses of the Holders of such securities pro rata on a
basis of the number of shares proposed to be sold by each of them.

         8.   INDEMNIFICATION.

              (a) Parent will indemnify each Holder, each of its officers and
directors and partners, and each person controlling such Holder within the
meaning of Section 15 of the Securities Act, with respect to which
registration has been effected pursuant to this Agreement, against all
expenses, claims, losses, damages or liabilities (or actions in respect
thereof), including any of the foregoing incurred in settlement of any
litigation, commenced or threatened, arising out of or based on any untrue
statement (or alleged untrue statement) of a material fact contained in any
registration statement, prospectus, offering circular or other document, or
any amendment or supplement thereto, incident to any such registration, or
based on any omission (or alleged omission) to state therein a material fact
required to be stated therein or necessary to make the statements therein, in
light of the circumstances in which they were made, not misleading and Parent
will reimburse each such Holder, each of its officers, directors and
partners, and each person controlling such Holder, for any legal and any
other expenses reasonably incurred in connection with investigating,
preparing or defending any such claim, loss, damage, liability or action,
PROVIDED that Parent will not be liable in any such case to the extent that
any such claim, loss, damage, liability or expense arises out of or is based
on any untrue statement or omission or alleged untrue statement or omission,
made in reliance upon and

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in conformity with written information furnished to Parent by an instrument
duly executed by such Holder or controlling person, and stated to be
specifically for use therein; and PROVIDED, FURTHER, that the foregoing
indemnity agreement is subject to the condition that, insofar as it relates
to any such untrue statement, alleged untrue statement, omission or alleged
omission made in a preliminary prospectus, such indemnity agreement shall not
inure to the benefit of any person, if a copy of the final prospectus or an
amended or supplemented prospectus, as applicable, 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, and if the final prospectus or
the amended or supplemented prospectus, as applicable, would have cured the
defect giving rise to the loss, liability, claim or damage. In no event,
however, shall Parent have any indemnification obligation to the extent that
the expenses, claims, losses, damages or liabilities as to which
indemnification is sought are in connection with an offer or sale made by a
person other than Parent in violation of the terms of this Agreement (a
"VIOLATION").

              (b) Each Holder will, severally and not jointly and severally,
if Registrable Securities held by such Holder are included in the securities
as to which a registration hereunder is effected, indemnify Parent, each of
its directors and officers, each person who controls Parent within the
meaning of Section 15 of the Securities Act, and each other such Holder, each
of its officers and directors and each person controlling such Holder within
the meaning of Section 15 of the Securities Act, against all claims, losses,
damages and liabilities (or actions in respect thereof) arising out of or
based on (i) a Violation by such Holder or (ii) any untrue statement (or
alleged untrue statement) of a material fact contained in any such
registration statement, prospectus, offering circular or other document, or
any omission (or alleged omission) to state therein a material fact required
to be stated therein or necessary to make the statements therein not
misleading, and will reimburse Parent, such Holders, such directors, officers
or control persons for any legal or any other expenses reasonably incurred in
connection with investigating or defending any such claim, loss, damage,
liability or action, but, in the case of clause (ii) above, only to the
extent that such untrue statement (or alleged untrue statement) or omission
(or alleged omission) is made in such registration statement, prospectus,
offering circular or other document in reliance upon and in conformity with
information furnished to Parent by such Holder. Notwithstanding the
foregoing, the liability of each Holder under this subsection 8.7(b) shall be
limited in an amount equal to the initial public offering price of the shares
sold by such Holder, unless such liability arises out of or is based on a
Violation or willful misconduct by such Holder.

              (c) Each party entitled to indemnification under this Section 8
(the "INDEMNIFIED PARTY") shall give notice to the party required to provide
indemnification (the "INDEMNIFYING PARTY") promptly after such Indemnified
Party has actual knowledge of any claim as to which indemnity may be sought,
and shall permit the Indemnifying Party to assume the defense of any such
claim or any litigation resulting therefrom, provided that (i) counsel for
the Indemnifying Party, who shall conduct the defense of such claim or
litigation, shall be approved by the Indemnified Party (whose approval shall
not unreasonably be withheld), and the Indemnified Party may participate in
such defense at such party's expense, (ii) that the failure of any
Indemnified Party to give notice as provided herein shall not relieve the
Indemnifying Party of its obligations under Section 8 of this Agreement
unless the failure to give such notice is materially prejudicial to an
Indemnifying Party's

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ability to defend such action, and then only to the extent that such
Indemnifying Party is materially prejudiced, and (iii) that the Indemnifying
Party shall not assume the defense for matters as to which there is a
conflict of interest or there are separate and different defenses. No
Indemnifying Party, in the defense of any such claim or litigation, shall,
except with the consent of each Indemnified Party (whose consent shall not be
unreasonably withheld), consent to entry of any judgment or enter into any
settlement which (i) does not include as an unconditional term thereof the
giving by the claimant or plaintiff to such Indemnified Party of a release
from all liability in respect to such claim or litigation or (ii) includes
admission of fault by the Indemnified Party. Notwithstanding the foregoing,
the liability of each Holder under this subsection 8.7(c) shall be limited in
an amount equal to the initial public offering price of the shares sold by
such Holder, unless such liability arises out of or is based on a Violation
or willful misconduct by such Holder.

         9.   INFORMATION BY HOLDER. The Holder or Holders of Registrable
Securities included in any registration hereunder shall furnish to Parent
such information regarding such Holder or Holders, the Registrable Securities
held by them and the distribution proposed by such Holder or Holders as
Parent may request in writing and as shall be required in connection with any
registration referred to in this Agreement.

         10.  RULE 144 REPORTING. With a view to making available the
benefits of certain rules and regulations of the Commission which may permit
the sale of the Restricted Securities to the public without registration
Parent agrees to use all reasonable efforts, at any time after the first
anniversary of the Effective Date, to:

              (a) Make and keep public information available, as those terms
are understood and defined in Rule 144 under the Securities Act; and

              (b) File with the Commission in a timely manner all reports and
other documents required of Parent under the Securities Act and the Exchange
Act.

         11.  TRANSFER OF REGISTRATION RIGHTS. The rights to cause Parent to
register securities granted to Holders under Section 5 may be assigned to a
transferee or assignee reasonably acceptable to Parent in connection with any
transfer or assignment of Registrable Securities by the Holder, provided that
(i) such transfer is otherwise effected in accordance with applicable
securities laws and the terms of this Agreement, (ii) such assignee or
transferee acquires at least 10,000 shares of Registrable Securities (as
adjusted for stock splits, stock dividends, stock combinations and the like),
(iii) written notice is promptly given to Parent and (iv) such transferee
agrees in writing to be bound by the provisions of this Agreement.
Notwithstanding the foregoing, the rights to cause Parent to register
securities may be assigned without compliance with item (ii) above to a
family member or trust for the benefit of a Holder who is an individual, or a
trust for the benefit of a family member of such a Holder. In addition, a
distribution of Shares issued in the Merger without additional consideration
to underlying beneficial owners in proportion to the beneficial ownership
interests (such as the general and limited partners, Stockholders and trust
beneficiaries of a Holder) shall not be deemed to be an "assignment" or
"transfer" for purposes of the Section 11 and such underlying beneficial
owners shall be entitled to the same rights and subject to the same
restrictions under this Agreement as the initial Holder from which the
Registrable Securities were received

                                       -9-

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without any additional action on the part of any party to this Agreement
other than reasonable notice to Parent of such distribution.

         12.  AMENDMENT. Except as otherwise provided above, any provision of
this Agreement may be amended or the observance thereof may be waived (either
generally or in a particular instance and either retroactively or
prospectively), only with the written consent of Parent and Holders of a
majority of the Registrable Securities remaining at the time such amendment
or waiver is made.

         13.  GOVERNING LAW. This Agreement shall be governed in all respects
by the laws of the State of California, without regard to conflict of laws
provisions.

         14.  ENTIRE AGREEMENT. This Agreement constitutes the full and
entire understanding and Agreement among the parties regarding the matters
set forth herein. Except as otherwise expressly provided herein, all other
agreements regarding the registration rights of the Company's Stockholders
shall hereby expire. The provisions hereof shall inure to the benefit of, and
be binding upon the successors, permitted assigns, heirs, executors and
administrators of the parties hereto.

         15.  NOTICES. All notices and other communications required or
permitted hereunder shall be in writing and shall be mailed by registered or
certified mail, postage prepaid, or otherwise delivered by facsimile
transmission, by hand or by messenger, addressed:

              (a) if to a Holder, at such Holder's address as set forth below
such Holder's signature on this Agreement, or at such other address as such
Holder shall have furnished to Parent.

              (b) if to Parent, to:

                           Adaptec, Inc.
                           691 Milpitas Boulevard
                           Milpitas, California  95035
                           Fax: (408) 957-7137
                           Attn: General Counsel

              or at such other address as Parent shall have furnished to the
Holders, with a copy to:

                           Wilson Sonsini Goodrich & Rosati, P.C.
                           650 Page Mill Road
                           Palo Alto, CA 94304-1050
                           Attn: Katharine A. Martin, Esq.
                           Fax: (650) 493-6811

         Each such notice or other communication shall for all purposes of
this Agreement be treated as effective or having been given when delivered if
delivered personally or by facsimile transmission, or, if sent by mail, at
the earlier of its receipt or 72 hours after the same has been

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deposited in a regularly maintained receptacle for the deposit of the United
States mail, addressed and mailed as aforesaid.

         16.  COUNTERPARTS. This Agreement may be executed in any number of
counterparts, each of which shall be an original, but all of which together
shall constitute one instrument.

                                       -11-

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         IN WITNESS WHEREOF, the parties hereto have executed this Agreement
as of the date first written above.

"PARENT"

Adaptec, Inc.
a Delaware corporation

By:    /s/ Tom Shea
   ------------------------------------
Name:  Tom Shea
     ----------------------------------
Title: VP & GM
      ---------------------------------


"THE HOLDERS"


By:  /s/ Eric D. Schneider
   ------------------------------------
Name:   Eric D. Schneider

By:  /s/ James H. Binger
   ------------------------------------
Name:   James H. Binger

By:  /s/ E.R. Kinney
   ------------------------------------
Name:   E.R. Kinney

By:  /s/ Margaret Velie Kinney
   ------------------------------------
Name:   Margaret Velie Kinney

By:  /s/ John D. French
   ------------------------------------
Name:   John D. French

By:  /s/ Mike Gustafson
   ------------------------------------
Name:   Mike Gustafson

By:  /s/ Marcy H. Shilling
   ------------------------------------
Name:   Marcy H. Shilling

By:  /s/ Erika Binger
   ------------------------------------
Name:   Erika Binger

By:  /s/ Meghan Brown
   ------------------------------------
Name:   Meghan Brown

<PAGE>

By:  /s/ Benjamin Binger
   ------------------------------------
Name:   Benjamin Binger

By:  /s/ Noa Staryk
   ------------------------------------
Name:   Noa Staryk

By:  /s/ Edward Bruggeman
   ------------------------------------
Name:   Edward Bruggeman








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