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                                                                   EXHIBIT 10.24

                                 PETS.COM, INC.

                       AMENDED AND RESTATED INVESTORS' RIGHTS AGREEMENT


        This Amended and Restated Investors' Rights Agreement (the "Agreement")
is made as of the 18th day of January, 2000, by and among Pets.com, Inc., a
California corporation (the "Company"), the investors listed on Exhibit A
hereto, each of which is herein referred to as an "Investor," and Greg McLemore,
who is also herein referred to as the "Founder".

                                    RECITALS

        A. The Company and certain of the Investors (the "Prior Investors") have
entered into either a Series A Preferred Stock Purchase Agreement dated April
22, 1999, pursuant to which the Company sold, and such Investors purchased,
shares of the Company's Series A Preferred Stock (the "Series A Shares"), a
Series B Preferred Stock Purchase Agreement dated June 18, 1999, pursuant to
which the Company sold, and such Investors purchased, shares of the Company's
Series B Preferred Stock (the "Series B Shares") or a Series B Preferred Stock
and Convertible Note Purchase Agreement dated November 5, 1999 (the "Prior
Purchase Agreement") pursuant to which the Company sold and such Investors
purchased shares of the Company's Series B Preferred Stock (the "Mezzanine
Series B Shares", and together with the Series A Shares and Series B Shares, the
"Previously Issued Preferred Stock").

        B. The Company, Founder and the Prior Investors have previously entered
into an Amended and Restated Investors' Rights Agreement, dated November 5, 1999
(the "Prior Rights Agreement"), which amended and restated that certain Amended
and Restated Investors' Rights Agreement dated June 18, 1999 between the
Company, Founder, and certain of the Prior Investors, which amended and restated
that certain Investors' Rights Agreement dated April 22, 1999 between the
Company, Founder and certain of the Prior Investors.

        C. The Company and certain of the Investors (the "Series C Investors")
have entered into a Series C Preferred Stock Purchase Agreement of even date
herewith (the "Purchase Agreement") pursuant to which the Company desires to
sell to the Series C Investors and the Series C Investors desire to purchase
from the Company shares of the Company's Series C Preferred Stock (the "Series C
Shares" and together with the Previously Issued Preferred Stock, the "Preferred
Stock"). A condition to the Series C Investors' obligations under the Purchase
Agreement is that the Company, Founder, Prior Investors and the Series C
Investors enter into this Agreement in order to provide the Investors with (i)
certain rights to register shares of the Company's Common Stock issuable upon
conversion of the Series A, Series B and Series C Preferred Stock held by the
Investors, (ii) certain rights to receive or inspect information pertaining to
the Company, (iii) certain rights to have a right of first offer with respect to
certain issuances by the Company of its securities, and (iv) certain additional
covenants of the Company. The Company, Founder, and the Prior Investors each
desire to induce the Series C Investors to


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purchase shares of Series C Preferred Stock pursuant to the Purchase Agreement
by agreeing to the terms and conditions set forth herein.

        D. The Company wishes to execute this Agreement and grant to the Series
C Investors the rights contained herein in order to fulfill such condition.

        E. The Company and the Prior Investors executing this Agreement together
represent sufficient signatory authority to amend and restate the Prior Rights
Agreement and to waive the Right of First Offer contained in Section 2.3 of the
Prior Rights Agreement with respect to those Prior Investors who are not
purchasing shares of Series C Preferred Stock pursuant to the Purchase
Agreement.

                                    AGREEMENT

        In consideration of the mutual promises and covenants hereinafter set
forth, and for certain other valuable considerations, the receipt of which is
hereby acknowledged, the parties hereby agree as follows:

        1. REGISTRATION RIGHTS. The Company, the Founder and the Investors
covenant and agree as follows:

               1.1    DEFINITIONS.  For purposes of this Section 1:

                    (a) The terms "register," "registered," and "registration"
refer to a registration effected by preparing and filing a registration
statement or similar document in compliance with the Securities Act of 1933, as
amended (the "Securities Act"), and the declaration or ordering of effectiveness
of such registration statement or document;

                    (b) The term "Registrable Securities" means (i) the shares
of Common Stock issuable or issued upon conversion of the Series A Preferred
Stock, Series B Preferred Stock and Series C Preferred Stock, (ii) the shares of
Common Stock issued to the Founder (the "Founder's Stock"), provided, however,
that for the purposes of Sections 1.2, 1.4, 1.13, 3 and 5.2 the Founder's Stock
shall not be deemed Registrable Securities and the Founder shall not be deemed a
Holder, and (iii) any other shares of Common Stock of the Company issued as (or
issuable upon the conversion or exercise of any warrant, right or other security
which is issued as) a dividend or other distribution with respect to, or in
exchange for or in replacement of, the shares listed in (i) and (ii); provided,
however, that the foregoing definition shall exclude in all cases any
Registrable Securities sold by a person in a transaction in which his or her
rights under this Agreement are not assigned. Notwithstanding the foregoing,
Common Stock or other securities shall only be treated as Registrable Securities
if and so long as they have not been (A) sold to or through a broker or dealer
or underwriter in a public distribution or a public securities transaction, or
(B) sold in a transaction exempt from the registration and prospectus delivery
requirements of the Securities Act under Section 4(1) thereof so that all
transfer restrictions, and restrictive legends with respect thereto, if any, are
removed upon the consummation of such sale;



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                    (c) The number of shares of "Registrable Securities then
outstanding" shall be determined by the number of shares of Common Stock
outstanding which are, and the number of shares of Common Stock issuable
pursuant to then exercisable or convertible securities which are, Registrable
Securities;

                    (d) The term "Holder" means any person owning or having the
right to acquire Registrable Securities or any assignee thereof in accordance
with Section 1.12 of this Agreement; provided, however, that the Founder shall
not be deemed to be a Holder with respect to Founder's Stock only for purposes
of Sections 1.2, 1.4 and 1.13, nor an Eligible Holder (as defined herein below
in Section 2.1) with respect to Founder's Stock only for purposes of Section
3.2.

                    (e) The term "Form S-3" means such form under the Securities
Act as in effect on the date hereof or any successor form that permits
significant incorporation by reference of a Company's filings under the
Securities Exchange Act of 1934, as amended (the "Exchange Act");

                    (f) The term "SEC" means the Securities and Exchange
Commission; and

                    (g) The term "Qualified IPO" means a firm commitment
underwritten public offering by the Company of shares of its Common Stock
pursuant to a registration statement under the Securities Act pursuant to which
all outstanding shares of the Company's Preferred Stock are converted into
Common Stock pursuant to Article III, Section 4(b) of the Company's Articles of
Incorporation.

               (h) The term "Affiliate" means, with respect to a specified
entity, any other entity directly or indirectly controlling or controlled by or
under direct or indirect common control with such specified entity. For purposes
of this definition, "control" when used with respect to any specified entity
means the power to direct the management and policies of such entity, whether
through the ownership of voting securities, by contract or otherwise; and the
terms "controlling" and "controlled" have meanings correlative to the foregoing.


               1.2 REQUEST FOR REGISTRATION.

                    (a) Subject to the conditions of this Section 1.2, if the
Company shall receive at any time after the earlier of (i) the fifth anniversary
of the date hereof, or (ii) six (6) months after the effective date of the first
registration statement for a public offering of securities of the Company (other
than a registration statement relating either to the sale of securities to
employees of the Company pursuant to a stock option, stock purchase or similar
plan or an SEC Rule 145 transaction), a written request from the Holders of at
least 33 1/3% of the Preferred Stock (or Common Stock converted therefrom) then
outstanding that the Company file a registration statement under the Securities
Act covering the registration of Registrable Securities, the anticipated
aggregate offering price, net of underwriting discounts and commissions, of
which are in excess of $5,000,000, then the Company shall, within ten (10) days
of the receipt



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thereof, give written notice of such request to all Holders and shall, subject
to the limitations of subsection 1.2(b), use its best efforts to effect as soon
as practicable, and in any event within 60 days of the receipt of such request,
the registration under the Securities Act of all Registrable Securities which
the Holders request to be registered within twenty (20) days of the mailing of
such notice by the Company in accordance with Section 3.3.

                    (b) If the Holders initiating the registration request
hereunder ("Initiating Holders") intend to distribute the Registrable Securities
covered by their request by means of an underwriting, they shall so advise the
Company as a part of their request made pursuant to this Section 1.2 and the
Company shall include such information in the written notice referred to in
subsection 1.2(a). The underwriter will be selected by a majority in interest of
the Initiating Holders and shall be reasonably acceptable to the Company. In
such event, the right of any Holder to include his Registrable Securities in
such registration shall be conditioned upon such Holder's participation in such
underwriting and the inclusion of such Holder's Registrable Securities in the
underwriting (unless otherwise mutually agreed by a majority in interest of the
Initiating Holders and such Holder) to the extent provided herein. All Holders
proposing to distribute their securities through such underwriting shall
(together with the Company as provided in subsection 1.5(e)) enter into an
underwriting agreement in customary form with the underwriter or underwriters
selected for such underwriting. Notwithstanding any other provision of this
Section 1.2, if the underwriter advises the Initiating Holders and the Company
in writing that marketing factors require a limitation of the number of shares
to be underwritten, then the Company shall so advise all Holders of Registrable
Securities which would otherwise be underwritten pursuant hereto, and the number
of shares of Registrable Securities that may be included in the underwriting
shall be allocated among all Holders thereof, including the Initiating Holders,
in proportion (as nearly as practicable) to the amount of Registrable Securities
of the Company owned by each Holder; provided, however, that the number of
shares of Registrable Securities to be included in such underwriting shall not
be reduced unless all other securities are first entirely excluded from the
underwriting.

                    (c) Notwithstanding the foregoing, if the Company shall
furnish to Holders requesting a registration statement pursuant to this Section
1.2, a certificate signed by the President of the Company stating that in the
good faith judgment of the Board of Directors of the Company, it would be
seriously detrimental to the Company and its shareholders for such registration
statement to be filed and it is therefore essential to defer the filing of such
registration statement, the Company shall have the right to defer such filing
for a period of not more than 90 days after receipt of the request of the
Initiating Holders; provided, however, that the Company may not utilize this
right more than once in any twelve-month period; and provided further that the
Company shall not register shares for its own account during such 90 day period,
but such prohibition shall not apply to the registration of Company shares in
connection with a merger or other strategic transaction by the Company.

                    (d) In addition, the Company shall not be obligated to
effect, or to take any action to effect, any registration pursuant to this
Section 1.2:



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                         (i) After the Company has effected two (2)
registrations pursuant to this Section 1.2 and such registrations have been
declared or ordered effective;

                         (ii) During the period starting with the date sixty
(60) days prior to the Company's good faith estimate of the date of filing of,
and ending on a date one hundred eighty (180) days after the effective date of,
a registration subject to Section 1.3 hereof; provided that the Company is
actively employing in good faith all reasonable efforts to cause such
registration statement to become effective; or

                         (iii) If the Initiating Holders propose to dispose of
shares of Registrable Securities that may be immediately registered on Form S-3
pursuant to a request made pursuant to Section 1.4 below.

               1.3 COMPANY REGISTRATION. If (but without any obligation to do
so) the Company proposes to register (including for this purpose a registration
effected by the Company for shareholders other than the Holders) any of its
stock under the Securities Act in connection with the public offering of such
securities (other than a registration relating solely to the sale of securities
to participants in a Company stock plan or a transaction covered by Rule 145
under the Securities Act, a registration in which the only stock being
registered is Common Stock issuable upon conversion of debt securities which are
also being registered, or any registration on any form which does not include
substantially the same information as would be required to be included in a
registration statement covering the sale of the Registrable Securities), the
Company shall, at such time, promptly give each Holder written notice of such
registration. Upon the written request of each Holder given within twenty (20)
days after mailing of such notice by the Company in accordance with Section 5.3,
the Company shall, subject to the provisions of Section 1.8, cause to be
registered under the Securities Act all of the Registrable Securities that each
such Holder has requested to be registered.

               1.4 FORM S-3 REGISTRATION. In case the Company shall receive from
any Holder or Holders of not less than thirty percent (30%) of the Preferred
Stock (or Common Stock converted therefrom) then outstanding, or from any Holder
or Holders of not less than thirty percent (30%) of the Series C Preferred Stock
(or Common Stock converted therefrom) then outstanding, a written request or
requests that the Company effect a registration on Form S-3 and any related
qualification or compliance with respect to all or a part of the Registrable
Securities owned by such Holder or Holders, the Company will:

                    (a) promptly give written notice of the proposed
registration, and any related qualification or compliance, to all other Holders;
and

                    (b) as soon as practicable, effect such registration and all
such qualifications and compliances as may be so requested and as would permit
or facilitate the sale and distribution of all or such portion of such Holder's
or Holders' Registrable Securities as are specified in such request, together
with all or such portion of the Registrable Securities of any other Holder or
Holders joining in such request as are specified in a written request given
within 15 days after receipt of such written notice from the Company; provided,
however, that the Company shall not be obligated to effect any such
registration, qualification or compliance


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pursuant to this Section 1.4: (i) if Form S-3 is not available for such offering
by the Holders; (ii) if the Holders, together with the holders of any other
securities of the Company entitled to inclusion in such registration, propose to
sell Registrable Securities and such other securities (if any) at an aggregate
price to the public (net of any underwriters' discounts or commissions) of less
than $5,000,000; (iii) if the Company shall furnish to the Holders a certificate
signed by the President of the Company stating that in the good faith judgment
of the Board of Directors of the Company, it would be seriously detrimental to
the Company and its shareholders for such Form S-3 Registration to be effected
at such time, in which event the Company shall have the right to defer the
filing of the Form S-3 registration statement for a period of not more than 90
days after receipt of the request of the Holder or Holders under this Section
1.4; provided, however, that the Company shall not utilize this right more than
once in any twelve month period; (iv) if the Company has, within the twelve (12)
month period preceding the date of such request, already effected two
registrations on Form S-3 for the Holders pursuant to this Section 1.4; (v) in
any particular jurisdiction in which the Company would be required to qualify to
do business or to execute a general consent to service of process in effecting
such registration, qualification or compliance; or (vi) during the period ending
one hundred eighty (180) days after the effective date of the Company's initial
registration statement subject to Section 1.3.

                    (c) Subject to the foregoing, the Company shall file a
registration statement covering the Registrable Securities and other securities
so requested to be registered as soon as practicable after receipt of the
request or requests of the Holders. Registrations effected pursuant to this
Section 1.4 shall not be counted as demands for registration or registrations
effected pursuant to Sections 1.2 or 1.3, respectively.

               1.5 OBLIGATIONS OF THE COMPANY. Whenever required under this
Section 1 to effect the registration of any Registrable Securities, the Company
shall, as expeditiously as reasonably possible:

                    (a) Prepare and file with the SEC a registration statement
with respect to such Registrable Securities and use its best efforts to cause
such registration statement to become effective, and, upon the request of the
Holders of a majority of the Registrable Securities registered thereunder, keep
such registration statement effective for up to one hundred twenty (120) days.

                    (b) Prepare and file with the SEC such amendments and
supplements to such registration statement and the prospectus used in connection
with such registration statement as may be necessary to comply with the
provisions of the Securities Act with respect to the disposition of all
securities covered by such registration statement for such period of time as the
registration statement remains on effective.

                    (c) Furnish to the Holders such numbers of copies of a
prospectus, including a preliminary prospectus, in conformity with the
requirements of the Securities Act, and such other documents as they may
reasonably request in order to facilitate the disposition of Registrable
Securities owned by them.



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                    (d) Use its best efforts to register and qualify the
securities covered by such registration statement under such other securities or
Blue Sky laws of such jurisdictions as shall be reasonably requested by the
Holders, provided that the Company shall not be required in connection therewith
or as a condition thereto to qualify to do business or to file a general consent
to service of process in any such states or jurisdictions.

                    (e) In the event of any underwritten public offering, enter
into and perform its obligations under an underwriting agreement, in usual and
customary form, with the managing underwriter of such offering. Each Holder
participating in such underwriting shall also enter into and perform its
obligations under such an agreement.

                    (f) During the period of time that such registration
statement remains effective, notify each Holder of Registrable Securities
covered by such registration statement at any time when (i) a prospectus
relating thereto is required to be delivered under the Securities Act of the
happening of any event as a result of which the prospectus included in such
registration statement, as then in effect, includes an untrue statement of a
material fact or omits to state a material fact required to be stated therein or
necessary to make the statements therein not misleading in the light of the
circumstances then existing or (ii) there is a stop order issued by the SEC
suspending effectiveness of the registration statement or the initiation of any
proceedings for that purpose or the receipt by the Company of any notification
with respect to the suspension of the qualification of the Registered Securities
for sale in any jurisdiction or the initiation of any such procedure.

                    (g) Cause all such Registrable Securities registered
pursuant hereunder to be listed on each securities exchange on which similar
securities issued by the Company are then listed.

                    (h) Provide a transfer agent and registrar for all
Registrable Securities registered pursuant hereunder and a CUSIP number for all
such Registrable Securities, in each case not later than the effective date of
such registration.

                    (i) Use its best efforts to furnish, at the request of any
Holder requesting registration of Registrable Securities pursuant to this
Section 1, on the date that such Registrable Securities are delivered to the
underwriters for sale in connection with a registration pursuant to this Section
1, if such securities are being sold through underwriters, or, if such
securities are not being sold through underwriters, on the date that the
registration statement with respect to such securities becomes effective, (i) an
opinion, dated such date, of the counsel representing the Company for the
purposes of such registration, in form and substance as is customarily given to
underwriters in an underwritten public offering, addressed to the underwriters,
if any, and to the Holders requesting registration of Registrable Securities and
(ii) a letter dated such date, from the independent certified public accountants
of the Company, in form and substance as is customarily given by independent
certified public accountants to underwriters in an underwritten public offering,
addressed to the underwriters, if any, and to the Holders requesting
registration of Registrable Securities.




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               1.6 FURNISH INFORMATION. It shall be a condition precedent to the
obligations of the Company to take any action pursuant to this Section 1 with
respect to the Registrable Securities of any selling Holder that such Holder
shall furnish to the Company such information regarding itself, the Registrable
Securities held by it, and the intended method of disposition of such securities
as shall be required to effect the registration of such Holder's Registrable
Securities. The Company shall have no obligation with respect to any
registration requested pursuant to Section 1.2 or Section 1.4 of this Agreement
if, as a result of the application of the preceding sentence, the number of
shares or the anticipated aggregate offering price of the Registrable Securities
to be included in the registration does not equal or exceed the number of shares
or the anticipated aggregate offering price required to originally trigger the
Company's obligation to initiate such registration as specified in subsection
1.2(a) or subsection 1.4(b)(ii), whichever is applicable.

               1.7 EXPENSES OF REGISTRATION.

                    (a) DEMAND REGISTRATION. All expenses other than
underwriting discounts and commissions incurred in connection with
registrations, filings or qualifications pursuant to Section 1.2, including
(without limitation) all registration, filing and qualification fees, printers'
and accounting fees, fees and disbursements of counsel for the Company, and the
reasonable fees and disbursements of one counsel for the selling Holders
selected by them with the approval of the Company, which approval shall not be
unreasonably withheld, shall be borne by the Company; provided, however, that
the Company shall not be required to pay for any expenses of any registration
proceeding begun pursuant to Section 1.2 if the registration request is
subsequently withdrawn at the request of the Holders of a majority of the
Registrable Securities to be registered (in which case all participating Holders
shall bear such expenses pro rata based upon the number of Registrable
Securities that were to be requested in the withdrawn registration), unless the
Holders of a majority of the Registrable Securities agree to forfeit their right
to one demand registration pursuant to Section 1.2; provided, further, however,
that if at the time of such withdrawal, the Holders have learned of a material
adverse change in the condition, business, or prospects of the Company from that
known to the Holders at the time of their request and have withdrawn the request
with reasonable promptness following disclosure by the Company of such material
adverse change, then the Holders shall not be required to pay any of such
expenses and shall retain their rights pursuant to Section 1.2.

                    (b) COMPANY REGISTRATION. All expenses other than
underwriting discounts and commissions incurred in connection with
registrations, filings or qualifications of Registrable Securities pursuant to
Section 1.3 for each Holder (which right may be assigned as provided in Section
1.12), including (without limitation) all registration, filing, and
qualification fees, printers' and accounting fees, fees and disbursements of
counsel for the Company and the reasonable fees and disbursements of one counsel
for the selling Holder or Holders selected by them with the approval of the
Company, which approval shall not be unreasonably withheld, shall be borne by
the Company.

                    (c) REGISTRATION ON FORM S-3. All expenses incurred in
connection with a registration requested pursuant to Section 1.4, including
(without limitation) all




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registration, filing, qualification, printers' and accounting fees and the
reasonable fees and disbursements of one counsel for the selling Holder or
Holders selected by them with the approval of the Company, which approval shall
not be unreasonably withheld, and counsel for the Company, and any underwriters'
discounts or commissions associated with Registrable Securities, shall be borne
by the Company.

               1.8 UNDERWRITING REQUIREMENTS. In connection with any offering
involving an underwriting of shares of the Company's capital stock, the Company
shall not be required under Section 1.3 to include any of the Holders'
securities in such underwriting unless they accept the terms of the underwriting
as agreed upon between the Company and the underwriters selected by it (or by
other persons entitled to select the underwriters) and enter into an
underwriting agreement in the customary form with an underwriter or
underwriters, and then, except as provided below, only in such quantity as the
underwriters determine in their sole discretion will not jeopardize the success
of the offering by the Company. If the total amount of securities, including
Registrable Securities, requested by shareholders to be included in such
offering exceeds the amount of securities sold other than by the Company that
the underwriters determine in their sole discretion is compatible with the
success of the offering, then the Company shall be required to include in the
offering only that number of such securities, including Registrable Securities,
which the underwriters determine in their sole discretion will not jeopardize
the success of the offering (the securities so included to be apportioned pro
rata among the selling shareholders according to the total amount of securities
entitled to be included therein owned by each selling shareholder or in such
other proportions as shall be agreed to by all such selling shareholders) but in
no event shall (i) the amount of securities of the selling Holders included in
the offering be reduced below thirty percent (30%) of the total amount of
securities included in such offering, unless such offering is the initial public
offering of the Company's securities, in which case, the selling shareholders
may be excluded if the underwriters make the determination described above and
no other shareholder's securities are included, (ii) any securities held by a
Founder be included if any securities held by any selling Holder are excluded,
or (iii) notwithstanding (i) above, any shares being sold by a shareholder
exercising a demand registration right similar to that granted in Section 1.2 be
excluded from such offering. For purposes of the preceding parenthetical
concerning apportionment, for any selling shareholder which is a holder of
Registrable Securities and which is a partnership or corporation, the partners,
retired partners and shareholders of such holder, or the estates and family
members of any such partners and retired partners and any trusts for the benefit
of any of the foregoing persons shall be deemed to be a single "selling
shareholder," and any pro-rata reduction with respect to such "selling
shareholder" shall be based upon the aggregate amount of shares carrying
registration rights owned by all entities and individuals included in such
"selling shareholder," as defined in this sentence.

               1.9 DELAY OF REGISTRATION. No Holder shall have any right to
obtain or seek an injunction restraining or otherwise delaying any such
registration as the result of any controversy that might arise with respect to
the interpretation or implementation of this Section 1.



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               1.10 INDEMNIFICATION. In the event any Registrable Securities are
included in a registration statement under this Section 1:

                    (a) To the extent permitted by law, the Company will
indemnify and hold harmless each Holder, any underwriter (as defined in the
Securities Act) for such Holder and each person, if any, who controls such
Holder or underwriter within the meaning of the Securities Act or the Exchange
Act, against any losses, claims, damages, or liabilities (joint or several) to
which they may become subject under the Securities Act, the Exchange Act or
other federal or state law, insofar as such losses, claims, damages, or
liabilities (or actions in respect thereof) arise out of or are based upon any
of the following statements, omissions or violations (collectively a
"Violation"): (i) any untrue statement or alleged untrue statement of a material
fact contained in such registration statement, including any preliminary
prospectus or final prospectus contained therein or any amendments or
supplements thereto, (ii) the omission or alleged omission to state therein a
material fact required to be stated therein, or necessary to make the statements
therein not misleading, or (iii) any violation or alleged violation by the
Company of the Securities Act, the Exchange Act, any state securities law or any
rule or regulation promulgated under the Securities Act, the Exchange Act or any
state securities law; and the Company will pay to each such Holder, underwriter
or controlling person, as incurred, any legal or other expenses reasonably
incurred by them in connection with investigating or defending any such loss,
claim, damage, liability, or action; provided, however, that the indemnity
agreement contained in this subsection 1.10(a) shall not apply to amounts paid
in settlement of any such loss, claim, damage, liability, or action if such
settlement is effected without the consent of the Company (which consent shall
not be unreasonably withheld), nor shall the Company be liable to any Holder,
underwriter or controlling person for any such loss, claim, damage, liability,
or action to the extent that it arises out of or is based upon a Violation which
occurs in reliance upon and in conformity with written information furnished
expressly for use in connection with such registration by any such Holder,
underwriter or controlling person.

                    (b) To the extent permitted by law, each selling Holder will
indemnify and hold harmless the Company, each of its directors, each of its
officers who has signed the registration statement, each person, if any, who
controls the Company within the meaning of the Securities Act, any underwriter,
any other Holder selling securities in such registration statement and any
controlling person of any such underwriter or other Holder, against any losses,
claims, damages, or liabilities (joint or several) to which any of the foregoing
persons may become subject, under the Securities Act, the Exchange Act or other
federal or state law, insofar as such losses, claims, damages, or liabilities
(or actions in respect thereto) arise out of or are based upon any Violation, in
each case to the extent (and only to the extent) that such Violation occurs in
reliance upon and in conformity with written information furnished by such
Holder expressly for use in connection with such registration; and each such
Holder will pay, as incurred, any legal or other expenses reasonably incurred by
any person intended to be indemnified pursuant to this subsection 1.10(b), in
connection with investigating or defending any such loss, claim, damage,
liability, or action; provided, however, that the indemnity agreement contained
in this subsection 1.10(b) shall not apply to amounts paid in settlement of any
such loss, claim, damage, liability or action if such settlement is effected
without the consent of the Holder, which consent shall not be unreasonably
withheld; provided, that in no event shall any indemnity under this



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subsection 1.10(b) exceed the net proceeds from the offering received by such
Holder, except in the case of willful fraud by such Holder.

                    (c) Promptly after receipt by an indemnified party under
this Section 1.10 of notice of the commencement of any action (including any
governmental action), such indemnified party will, if a claim in respect thereof
is to be made against any indemnifying party under this Section 1.10, deliver to
the indemnifying party a written notice of the commencement thereof and the
indemnifying party shall have the right to participate in, and, to the extent
the indemnifying party so desires, jointly with any other indemnifying party
similarly noticed, to assume the defense thereof with counsel mutually
satisfactory to the parties; provided, however, that an indemnified party
(together with all other indemnified parties which may be represented without
conflict by one counsel) shall have the right to retain one separate counsel,
with the reasonable fees and expenses to be paid by the indemnifying party, if
representation of such indemnified party by the counsel retained by the
indemnifying party would be inappropriate due to actual or potential differing
interests between such indemnified party and any other party represented by such
counsel in such proceeding. The failure to deliver written notice to the
indemnifying party within a reasonable time of the commencement of any such
action, if prejudicial to its ability to defend such action, shall relieve such
indemnifying party of any liability to the indemnified party under this Section
1.10 to the extent prejudicial, but the omission so to deliver written notice to
the indemnifying party will not relieve it of any liability that it may have to
any indemnified party otherwise than under this Section 1.10.

                    (d) If the indemnification provided for in this Section 1.10
is held by a court of competent jurisdiction to be unavailable to an indemnified
party with respect to any loss, liability, claim, damage or expense referred to
therein, then the indemnifying party, in lieu of indemnifying such indemnified
party hereunder, shall contribute to the amount paid or payable by such
indemnified party as a result of such loss, liability, claim, damage, or expense
in such proportion as is appropriate to reflect the relative fault of the
indemnifying party on the one hand and of the indemnified party on the other in
connection with the statements or omissions that resulted in such loss,
liability, claim, damage or expense as well as any other relevant equitable
considerations; provided, that in no event shall any contribution by a Holder
under this Subsection 1.10(d) when aggregated with amounts paid pursuant to
Subsection 1.10(b) hereof, exceed the net proceeds from the offering received by
such Holder, except in the case of willful fraud by such Holder. The relative
fault of the indemnifying party and of the indemnified party shall be determined
by reference to, among other things, whether the untrue or alleged untrue
statement of a material fact or the omission to state a material fact relates to
information supplied by the indemnifying party or by the indemnified party and
the parties' relative intent, knowledge, access to information, and opportunity
to correct or prevent such statement or omission.

                    (e) Notwithstanding the foregoing, to the extent that the
provisions on indemnification and contribution contained in the underwriting
agreement entered into in connection with the underwritten public offering are
in conflict with the foregoing provisions, the provisions in the underwriting
agreement shall control. No Holder shall be required to participate in a
registration pursuant to which it would be required to execute an underwriting
agreement in connection with a registration that imposes indemnification or
contribution



                                      -11-
<PAGE>   12

obligations on such Holder more onerous than those imposed hereunder; provided
however, that the Company shall not be deemed to breach the provisions of
Section 1.2, 1.3 or 1.4 if a Holder is not permitted to participate in a
registration on account of such Holder's refusal to execute an underwriting
agreement on the basis of this Subsection 1.10(e).

                    (f) The obligations of the Company and Holders under this
Section 1.10 shall survive the completion of any offering of Registrable
Securities in a registration statement under this Section 1, and otherwise.

               1.11 REPORTS UNDER SECURITIES EXCHANGE ACT OF 1934. With a view
to making available to the Holders the benefits of Rule 144 promulgated under
the Securities Act and any other rule or regulation of the SEC that may at any
time permit a Holder to sell securities of the Company to the public without
registration or pursuant to a registration on Form S-3, the Company agrees to:

                    (a) make and keep public information available, as those
terms are understood and defined in SEC Rule 144, at all times after ninety (90)
days after the effective date of the first registration statement filed by the
Company for the offering of its securities to the general public so long as the
Company remains subject to the periodic reporting requirements under Sections 13
or 15(d) of the Exchange Act;

                    (b) take such action, including the voluntary registration
of its Common Stock under Section 12 of the Exchange Act, as is necessary to
enable the Holders to utilize Form S-3 for the sale of their Registrable
Securities, such action to be taken as soon as practicable after the end of the
fiscal year in which the first registration statement filed by the Company for
the offering of its securities to the general public is declared effective;

                    (c) file with the SEC in a timely manner all reports and
other documents required of the Company under the Securities Act and the
Exchange Act; and

                    (d) furnish to any Holder, so long as the Holder owns any
Registrable Securities, forthwith upon request (i) a written statement by the
Company that it has complied with the reporting requirements of SEC Rule 144 (at
any time after ninety (90) days after the effective date of the first
registration statement filed by the Company), the Securities Act and the
Exchange Act (at any time after it has become subject to such reporting
requirements), or that it qualifies as a registrant whose securities may be
resold pursuant to Form S-3 (at any time after it so qualifies), (ii) a copy of
the most recent annual or quarterly report of the Company and such other reports
and documents so filed by the Company, and (iii) such other information as may
be reasonably requested in availing any Holder of any rule or regulation of the
SEC which permits the selling of any such securities without registration or
pursuant to such form.

               1.12 ASSIGNMENT OF REGISTRATION RIGHTS. The rights to cause the
Company to register Registrable Securities pursuant to this Section 1 may be
assigned (but only with all related obligations) by a Holder to a transferee or
assignee of such securities that (i) is an Affiliate, partner, limited partner,
retired partner, member or former member of a Holder, (ii) is a Holder's family
member or trust for the benefit of an individual Holder or (iii) is a transferee
or


                                      -12-
<PAGE>   13

assignee of at least 100,000 (appropriately adjusted to reflect subsequent stock
splits, stock dividends, combinations or other recapitalizations) shares of such
securities; provided the Company is, within a reasonable time after such
transfer, furnished with written notice of the name and address of such
transferee or assignee and the securities with respect to which such
registration rights are being assigned; and provided, further, that such
assignment shall be effective only if immediately following such transfer the
further disposition of such securities by the transferee or assignee is
restricted under the Securities Act. For the purposes of determining the number
of shares of Registrable Securities held by a transferee or assignee, the
holdings of transferees and assignees of (i) a partnership who are partners or
retired partners of such partnership (including spouses and ancestors, lineal
descendants and siblings of such partners or spouses who acquire Registrable
Securities by gift, will or intestate succession) or (ii) a corporation or
limited liability company which is an Affiliate of such entity shall be
aggregated together and with the partnership or other entity, as the case may
be; provided that all assignees and transferees who would not qualify
individually for assignment of registration rights shall have a single
attorney-in-fact for the purpose of exercising any rights, receiving notices or
taking any action under Section 1.

               1.13 LIMITATIONS ON SUBSEQUENT REGISTRATION RIGHTS. From and
after the date of this Agreement, the Company shall not, without the prior
written consent of the Holders of at least seventy percent (70%) of the
outstanding Registrable Securities, not including the Founder's Stock, enter
into any agreement with any holder or prospective holder of any securities of
the Company which would allow such holder or prospective holder (a) to include
such securities in any registration filed under Section 1.2 or 1.3 hereof,
unless under the terms of such agreement, such holder or prospective holder may
include such securities in any such registration only to the extent that the
inclusion of his securities will not reduce the amount of the Registrable
Securities of the Holders which are included in such registration, (b) to make a
demand registration which could result in such registration statement being
declared effective prior to the earlier of either of the dates set forth in
subsection 1.2(a) or within one hundred twenty (120) days of the effective date
of any registration effected pursuant to Section 1.2 or (c) to receive rights
pari passu or senior to those granted the Investors hereunder.

               1.14 MARKET-STANDOFF AGREEMENT.

                    (a) MARKET-STANDOFF PERIOD; AGREEMENT. In connection with
the initial public offering of the Company's securities and upon request of the
Company or the underwriters managing such offering of the Company's securities,
each Holder agrees not to sell, make any short sale of, loan, grant any option
for the purchase of, or otherwise dispose of any securities of the Company
acquired by such Holder in a private transaction (other than those included in
the registration) without the prior written consent of the Company or such
underwriters, as the case may be, for such period of time (not to exceed 180
days) from the effective date of such registration as may be requested by the
Company or such managing underwriters and to execute an agreement reflecting the
foregoing as may be requested by the underwriters at the time of the Company's
initial public offering.



                                      -13-
<PAGE>   14

                    (b) LIMITATIONS. The obligations described in Section
1.14(a) shall apply only if all officers, directors and one-percent security
holders of the Company and all other persons with registration rights (whether
or not pursuant to this Agreement) enter into similar agreements, and shall not
apply to a registration relating solely to employee benefit plans, or to a
registration relating solely to a transaction pursuant to Rule 145 under the
Securities Act.

                    (c) STOP-TRANSFER INSTRUCTIONS. In order to enforce the
foregoing covenants, the Company may impose stop-transfer instructions with
respect to the securities of each Holder (and the securities of every other
person subject to the restrictions in Section 1.14(a)) until the end of such
period.

                    (d) TRANSFEREES BOUND. Each Holder agrees that it will not
transfer securities of the Company unless each transferee agrees in writing to
be bound by all of the provisions of this Section 1.14, provided that this
Section 1.14(d) shall not apply to transfers pursuant to a registration
statement or transfers after the six-month anniversary of the effective date of
the Company's initial registration statement subject to this Section 1.14.

               1.15 TERMINATION OF REGISTRATION RIGHTS. No Holder shall be
entitled to exercise any right provided for in this Section 1 after the earlier
of (i) seven (7) years following the consummation of a Qualified IPO, or (ii)
such time as Rule 144 or another similar exemption under the Securities Act is
available for the sale of all of such Holder's shares during a three (3)-month
period without registration.

        2. COVENANTS OF THE COMPANY.

               2.1 DELIVERY OF FINANCIAL STATEMENTS. The Company shall deliver
to each Holder of at least 100,000 shares of Registrable Securities (as adjusted
for stock splits, stock dividends, recapitalizations and the like) (each, an
"Eligible Holder"):

                    (a) as soon as practicable, but in any event within ninety
(90) days after the end of each fiscal year of the Company, an income statement
for such fiscal year, a balance sheet of the Company and statement of
shareholder's equity as of the end of such year, and a statement of cash flows
for such year, such year-end financial reports to be in reasonable detail,
prepared in accordance with generally accepted accounting principles ("GAAP"),
and audited and certified by an independent public accounting firm of nationally
recognized standing selected by the Company;

                    (b) within thirty (30) days of the end of each month, an
unaudited income statement and a statement of cash flows and balance sheet for
and as of the end of such month, in reasonable detail;

                    (c) as soon as practicable, but in any event thirty (30)
days prior to the end of each fiscal year, a budget and business plan for the
next fiscal year, prepared on a monthly basis, including balance sheets, income
statements and statements of cash flows for such months and, as soon as
prepared, any other budgets or revised budgets prepared by the Company; and




                                      -14-
<PAGE>   15

                    (d) with respect to the financial statements called for in
subsection (b) of this Section 2.1, an instrument executed by the Chief
Financial Officer or President of the Company and certifying that such
financials were prepared in accordance with GAAP consistently applied with prior
practice for earlier periods (with the exception of footnotes that may be
required by GAAP) and fairly present the financial condition of the Company and
its results of operation for the period specified, subject to year-end audit
adjustment, provided that the foregoing shall not restrict the right of the
Company to change its accounting principles consistent with GAAP, if the Board
of Directors determines that it is in the best interest of the Company to do so.

               2.2 INSPECTION. The Company shall permit each Eligible Holder
(except for an Eligible Holder reasonably deemed by the Company to be a
competitor of the Company), at such Eligible Holder's expense, to visit and
inspect the Company's properties, to examine its books of account and records
and to discuss the Company's affairs, finances and accounts with its officers,
all at such reasonable times as may be requested by the Investor; provided,
however, that the Company shall not be obligated pursuant to this Section 2.2 to
provide access to any information which it reasonably considers to be a trade
secret or similar confidential information. For purposes of this Section 2.2,
Amazon.com, Inc. ("Amazon.com") shall not be considered a competitor of the
Company.

               2.3 RIGHT OF FIRST OFFER. Subject to the terms and conditions
specified in this Section 2.3, the Company hereby grants to each Eligible Holder
a right of first offer with respect to future sales by the Company of its Shares
(as hereinafter defined). For the avoidance of doubt and for purposes of this
Section 2.3, the Founder shall be considered an Eligible Holder only with
respect to the Series A Preferred Stock held by him, and his pro rata share (as
used in Section 2.3(b) below) shall be calculated based exclusively on the
shares of Series A Preferred Stock then held by him. An Eligible Holder who
chooses to exercise the right of first offer may designate as purchasers under
such right itself, its current or former partners, members or Affiliates, or a
corporation or limited liability company which is an Affiliate of such entity,
in such proportions as it deems appropriate.

               Each time the Company proposes to offer any shares of, or
securities convertible into or exercisable for any shares of, any class of its
capital stock ("Shares"), the Company shall first make an offering of such
Shares to each Eligible Holder in accordance with the following provisions:

                    (a) The Company shall deliver a notice by certified mail
("Notice") to the Eligible Holders stating (i) its bona fide intention to offer
such Shares, (ii) the number of such Shares to be offered, and (iii) the price
and terms, if any, upon which it proposes to offer such Shares.

                    (b) Within 15 calendar days after delivery of the Notice,
(i) each Eligible Holder (including Amazon.com) may elect to purchase or obtain,
at the price and on the terms specified in the Notice, up to that portion of
such Shares which equals the proportion that the number of shares of Common
Stock issued and held, or issuable upon conversion and




                                      -15-
<PAGE>   16

exercise of all convertible or exercisable securities then held by such Eligible
Holder bears to the total number of shares of Common Stock then outstanding
(assuming full conversion and exercise of all convertible or exercisable
securities); and (ii) Amazon.com may elect to purchase or obtain, at the price
and on the terms specified in the Notice, the lesser of (A) all such remaining
Shares and (B) up to that portion of such Shares that, when aggregated with the
total number of shares of the Company's Common Stock issued and held, or
issuable upon conversion or exercise of all convertible or exercisable
securities then held by Amazon.com, plus all shares which Amazon.com has the
right to purchase under Subsection (i) of this Section 2.3(b), equals 46% of the
total number of shares of the Company's Common Stock then outstanding on a
fully-diluted basis (assuming full conversion and exercise of all convertible or
exercisable securities of the Company, including securities reserved for
issuance and not granted under the Company's stock and option plans) (the
"Threshold Percentage"). The Company shall promptly, in writing, inform each
Eligible Holder that purchases all the shares available to it (each, a
"Fully-Exercising Investor") of any other Eligible Holder's failure to do
likewise. During the ten (10)-day period commencing after receipt of such
information, each Fully-Exercising Investor shall be entitled to obtain that
portion of the Shares for which Eligible Holders were entitled to subscribe but
which were not subscribed for by the Eligible Holders that is equal to the
proportion that the number of shares of Common Stock issued and held, or
issuable upon conversion and exercise of all convertible or exercisable
securities then held, by such Fully-Exercising Investor bears to the total
number of shares of Common Stock then outstanding (assuming full conversion and
exercise of all convertible or exercisable securities), provided, however, that
in no event shall Amazon.com be entitled to purchase under this Section 2.3 a
number of Shares that, when aggregated with the total number of shares of Common
Stock issued and held, or issuable upon conversion or exercise of all
convertible or exercisable securities then held by Amazon.com, plus all shares
which Amazon.com has the right to purchase under Subsection (i) of this Section
2.3(b), equals an amount greater than the Threshold Percentage. The right of
Amazon.com to purchase up to the Threshold Percentage pursuant to this Section
2.3 may not be transferred to any third party or parties, other than to a
corporation or limited liability company which is a parent or subsidiary of
Amazon.com.

                    (c) The Company may, during the 45-day period following the
expiration of the later of the ten-day or fifteen-day period provided in
subsection 2.3(b) hereof, offer the remaining unsubscribed portion of the Shares
to any person or persons at a price not less than, and upon terms no more
favorable to the offeree than those specified in the Notice. If the Company does
not enter into an agreement for the sale of the Shares within such period, or if
such agreement is not consummated within 60 days of the execution thereof, the
right provided hereunder shall be deemed to be revived and such Shares shall not
be offered unless first reoffered to the Eligible Holders in accordance
herewith.

                    (d) The right of first offer in this Section 2.3 shall not
be applicable (i) to the issuance or sale of Common Stock (or options therefor)
to employees, consultants and directors, pursuant to plans or agreements
approved by the Board of Directors for the primary purpose of soliciting or
retaining their services, (ii) to or after consummation of a Qualified IPO,
except that with respect to Amazon.com (subject to Sections 2.3(e) through (i)
below) and with respect to Bowman Capital Management or any fund over which
Bowman Capital Management




                                      -16-
<PAGE>   17

exercises control or is under common control with (collectively "Bowman")
(subject to Sections 2.3(j) and (k) below), the right of first offer in this
Section 2.3 shall terminate immediately after consummation of a Qualified IPO,
(iii) to the issuance of securities pursuant to the conversion or exercise of
convertible or exercisable securities, (iv) to the issuance of securities to
financial institutions or lessors in connection with commercial credit
arrangements, equipment financings, or similar transactions, or (v) to the
issuance or sale of the Series A Preferred Stock or Series B Preferred Stock.

                    (e) Notwithstanding anything in this Section 2.3 to the
contrary, and subject to paragraphs (f), (g), (h) and (i) below, to the extent
permissible under the federal securities laws, the rules and regulations of the
National Association of Securities Dealers, Inc. (the "NASD"), and all other
applicable laws, rules and regulations, the Company hereby agrees that in
connection with the Company's initial public offering of Common Stock pursuant
to a registration statement filed under the Securities Act (the "IPO"), the
Company shall use reasonable efforts to cause the managing underwriter or
underwriters (who were selected with the prior approval, not to be unreasonably
withheld, of Amazon.com) for such IPO to offer to Amazon.com the right to
purchase up to such number of shares of the Company's Common Stock to be sold in
the IPO (the "IPO Shares") sufficient to raise Amazon.com's total equity
ownership in the Company upon consummation of the IPO to its permitted Threshold
Percentage. The IPO Shares shall be offered to Amazon.com on the same terms and
at the same price at which they are being offered to the public. If Amazon.com
wishes to purchase the IPO Shares, it shall promptly respond to such offer
within the time frame reasonably requested by the managing underwriter(s). The
foregoing provisions are not intended to be, and shall not be construed as, an
offer by the Company to sell the IPO Shares. Any such offer will be made
pursuant to applicable requirements of the federal securities laws, the rules
and regulations of the NASD, and all other applicable laws, rules and
regulations, as well as the provisions of this Section 2.3(e).

                    (f) In the event that despite all purchases by Amazon.com of
shares of the Company's capital stock under this Section 2.3, Amazon.com's total
equity ownership in the Company will not reach its permitted Threshold
Percentage upon consummation of the IPO, then to the extent permissible under
the federal securities laws, the rules and regulations of the NASD, and all
other applicable laws, rules and regulations, and to the extent the managing
underwriter(s) determine that the sale of the Additional Shares (as defined
below) will not jeopardize the success of the IPO, the Company shall use its
best efforts to sell and issue to Amazon.com, and Amazon.com may, but shall not
be required to, purchase from the Company, in a private placement transaction
such number of shares of the Company's Common Stock ("Additional Shares")
sufficient to raise Amazon.com's total equity ownership in the Company
(including, without limitation, any IPO Shares and Additional Shares purchased)
to its permitted Threshold Percentage upon consummation of the IPO. The price
per share paid by Amazon.com for such Additional Shares shall be the price at
which the IPO Shares are offered to the public. The purchase of such shares
shall be contingent upon the closing of the IPO. The foregoing provisions are
not intended to be, and shall not be construed as, an offer by the Company to
sell such shares. Any such offer will be made pursuant to applicable
requirements of the federal




                                      -17-
<PAGE>   18

securities laws, the rules and regulations of the NASD, and all other applicable
laws, rules and regulations, as well as the provisions of this Section 2.3(f).

                    (g) Notwithstanding Sections 2.3(e) and (f) above, if the
managing underwriter(s) of the IPO determine in their sole discretion that
Amazon.com's purchase of IPO Shares in the amount otherwise specified in Section
(e) or Amazon.com's purchase of Additional Shares in the amount otherwise
specified in Section (f) is not compatible with the success of the IPO, then the
managing underwriter(s) may prohibit Amazon.com from purchasing any IPO Shares
or Additional Shares or may allow Amazon.com to purchase only that number of IPO
Shares or Additional Shares that the managing underwriter(s) determine in their
sole discretion will not jeopardize the success of the IPO; provided however
that in no event shall Bowman be permitted to purchase any shares in the
Company's IPO pursuant to Section 2.3(j) below until Amazon.com shall have been
permitted to purchase its full allocation of IPO Shares.

                    (h) Notwithstanding anything in this Section 2.3 to the
contrary, and subject to paragraph (i) below, to the extent Amazon.com is not
permitted to purchase the number of shares of additional shares of the Company's
Common Stock which it has requested to purchase pursuant to Section 2.3(e) (the
"Refused Shares"), the Company hereby agrees that for a period of one year
following the IPO, the Company shall in good faith negotiate with Amazon.com to
agree upon a means by which Amazon.com may purchase the Refused Shares (as
adjusted for stock splits, stock dividends, recapitalizations and the like) at
the then fair market value of the Company's Common Stock. Such means may include
a private placement of shares by the Company or the sale of shares by the
Company to Amazon.com in a secondary public offering.

                    (i) The rights of Amazon.com under Sections 2.3(e), (f) and
(h) above shall terminate at such time as Amazon.com has disposed of any shares
of the Company's capital stock held by it as of the time of this Agreement or
acquired thereafter, provided however, that any transfer of shares by Amazon.com
to a corporation or limited liability company which is a parent or subsidiary of
Amazon.com will not be deemed to trigger the terms of this Section 2.3(i).

                    (j) Notwithstanding anything in this Section 2.3 to the
contrary, and subject to paragraphs (g) above and (k) below, to the extent
permissible under the federal securities laws, the rules and regulations of the
NASD, and all other applicable laws, rules and regulations, the Company hereby
agrees that in connection with the Company's IPO, the Company shall use
reasonable efforts to cause the managing underwriter or underwriters for such
IPO to offer to Bowman the right to purchase up to two and one-half percent
(2.5%) of the shares offered and sold by the Company in the IPO. The IPO shares
shall be offered to Bowman on the same terms and at the same price at which they
are being offered to the public. If Bowman wishes to purchase such shares, it
shall promptly respond to such offer within the time frame reasonably requested
by the managing underwriter(s). The foregoing provisions are not intended to be,
and shall not be construed as, an offer by the Company to sell such shares. Any
such offer will be made pursuant to applicable requirements of the federal
securities laws, the rules and regulations of the NASD, and all other applicable
laws, rules and regulations, as well as the provisions of this Section 2.3(j).
Notwithstanding the foregoing provisions, if the managing underwriter(s) of the
IPO determine in their sole discretion that Bowman's purchase of such




                                      -18-
<PAGE>   19

shares is not compatible with the success of the IPO, then the managing
underwriter(s) may prohibit Bowman from purchasing any shares in the IPO or may
allow Bowman to purchase only that number of shares that the managing
underwriter(s) determine in their sole discretion will not jeopardize the
success of the IPO.

                    (k) The rights of Bowman under Section 2.3(j) above shall
terminate at such time as Bowman has disposed of any shares of the Company's
capital stock held by it as of the time of this Agreement or acquired
thereafter.

               2.4 REIMBURSEMENT OF DIRECTOR EXPENSES. The Company shall
reimburse the reasonable documented expenses incurred by the directors elected
by the holders of Series A Preferred Stock and Series B Preferred Stock pursuant
to that certain Amended and Restated Voting Agreement between the Company and
the Investors of even date herewith (the "Voting Agreement") in connection with
such directors' attendance of meetings of the Company's Board of Directors
promptly upon receipt of documentation of such expenses.

               2.5 NOTICE OF SALE OF COMPANY. Until the Standstill Termination
Date (as defined below in Section 4.1), promptly following commencement of any
discussion with any third-party and in any event at least ten (10) days prior to
signing any letter of intent (whether binding or non-binding) or any definitive
documents, the Company shall provide Amazon.com with written notice of its
intent to enter into an agreement to sell, convey, or otherwise dispose of all
or substantially all of its property or business or merge into or consolidate
with any other corporation (other than a wholly-owned subsidiary corporation) or
effect any other transaction or series of related transactions in which more
than fifty percent (50%) of the Company's voting power would be disposed of,
provided such notice shall not be required in connection with a merger effected
solely for the purpose of changing the domicile of the Company.

               2.6 VESTING UNDER 1999 STOCK PLAN. Unless otherwise approved by a
majority of the Company's Board of Directors, options and Common Stock granted
by the Company pursuant to its 1999 Stock Plan (the "Plan") will be subject to
the following vesting schedule: 25% of the shares comprising each grant to
employees shall vest on the one-year anniversary of the vesting commencement
date for such grant, and thereafter 1/48th of the shares comprising the grant
shall vest on each monthly anniversary of the vesting commencement date for such
grant. Unvested shares of Common Stock issued to employees pursuant to the Plan
will be subject to the Company's right of repurchase at the original grantee's
purchase price.

               2.7 CONFLICTS OF INTERESTS. The Company shall use its best
efforts to ensure that the Company's employees, during the term of their
employment with the Company, do not engage in activities which would result in a
conflict of interest with the Company. The Company's obligations hereunder
include, but are not limited to, requiring that the Company's employees devote
their primary productive time, ability and attention to the business of the
Company (provided, however, the Company's employees may engage in other
professional activity if such activity does not materially interfere with their
obligations to the Company), requiring that the Company's employees enter into
agreements regarding proprietary information




                                      -19-
<PAGE>   20

and confidentiality and inventions, and preventing the Company's employees from
engaging or participating in any business that is in competition with the
business of the Company.

               2.8 QUALIFIED SMALL BUSINESS. The Company shall use its best
efforts to provide notice to the holders of its Series A and Series B Preferred
Stock of any proposed action that could affect its qualification as a "Qualified
Small Business" as defined in Section 1202(d) of the Code, and covenants that so
long as Registrable Securities are held by such holders (or a transferee or
assignee of such holders), prior to taking any such action, it will discuss such
action with the Eligible Holders holding Series A and Series B Preferred Stock.
To the extent that such disqualification could be avoided by parties, other than
the Company, repurchasing shares of outstanding stock, the Eligible Holders
holding Series A or Series B Preferred Stock or any other persons or entities
designated by the Company's Board of Directors may purchase such stock in
accordance with the procedures set forth in Section 1.1(b) of the Amended and
Restated Right of First Refusal and Co-Sale Agreement dated the same date
herewith. The Company shall use its best efforts to comply with the reporting
requirements of the State of California regarding "Qualified Small Business
Stock" and similar federal regulations when and if promulgated.

               2.9 PROPRIETARY AGREEMENTS. The Company shall have each officer,
employee and consultant of the Company execute the Company's standard form of
non-disclosure and proprietary information agreement prior to disclosing any
proprietary information to any such officer, employee and consultant. The
Company will use its best efforts to prevent any employee from violating the
confidentiality and proprietary information agreement entered into between the
Company and each of its officers, employees and consultants.

               2.10 DIRECTORS AND OFFICERS INSURANCE. The Company will use its
best efforts to maintain directors and officers insurance, upon a determination
by the Company's Board of Directors that such insurance is economically
feasible.

               2.11 DIRECTORS' LIABILITY AND INDEMNIFICATION. The Company's
Fifth Amended and Restated Articles of Incorporation (the "Restated Articles")
and Bylaws shall provide (a) for elimination of the liability of director to the
maximum extent permitted by law and (b) for indemnification of directors for
acts on behalf of the Company to the maximum extent permitted by law. In
addition, the Company shall indemnify such directors to the maximum extent
permissible under California law pursuant to an indemnification agreement.

               2.12 AUDITORS. The Company will retain independent public
accountants of recognized national standing (i.e., a firm acknowledged to be
among the Big Five or their successors) who shall audit the Company's financial
statements at the end of each fiscal year.

               2.13 EXTRAORDINARY REMUNERATION. The Board of Directors may not
approve any plan or action to grant extraordinary remuneration to management in
connection with the sale of the Company or any subsidiary of the Company, or the
termination of employment or otherwise, unless such plan or action has been
approved by the non-employee members of the Board of Directors.




                                      -20-
<PAGE>   21

               2.14 APPROVAL OF HOLDERS OF PREFERRED STOCK. The Company shall
disclose all terms, including those provided in side letters, relating to the
issuances described in Article III(B), Sections 6(b)(ii), 6(c)(ii) and 6(d)(ii)
of the Restated Articles to the holders of Preferred Stock before such holders
are to vote on such issuances.

               2.15 TERMINATION OF COVENANTS.

                    (a) The covenants set forth in Sections 2.1 through 2.3 and
2.6 through 2.14 shall terminate as to each Investor and be of no further force
or effect (i) immediately prior to the consummation of a Qualified IPO (except
as otherwise noted in Section 2.3), or (ii) when the Company shall sell, convey,
or otherwise dispose of or encumber all or substantially all of its property or
business or merge into or consolidate with any public corporation (other than a
wholly-owned subsidiary corporation) or effect any other transaction or series
of related transactions in which more than fifty percent (50%) of the voting
power of the Company is disposed of, provided that this subsection (ii) shall
not apply to a merger effected exclusively for the purpose of changing the
domicile of the Company.

                    (b) The covenants set forth in Sections 2.1 and 2.2 shall
terminate as to each Holder and be of no further force or effect when the
Company first becomes subject to the periodic reporting requirements of Sections
13 or 15(d) of the Exchange Act, if this occurs earlier than the events
described in Section 2.16(a) above.

                    (c) The covenant set forth in Section 2.4 shall terminate
and be of no further force or effect at such time as the Voting Agreement
terminates pursuant to its terms.

        3. COVENANTS OF THE INVESTORS.

               3.1 NOTICE OF PROPOSED TRANSFER. Prior to any transfer of
Registrable Securities, the Holder of such Registrable Securities (the "Seller")
must give to the Company a written notice signed by the Seller (the "Seller's
Notice") stating (a) the Seller's bona fide intention to transfer such
Registrable Securities (the "Offered Stock") and the name and address of the
proposed transferee (the "Transferee"); (b) the number of shares of the Offered
Stock; and (c) the bona fide cash price or, in reasonable detail, other
consideration, per share for which the Seller proposes to transfer such Offered
Stock (the "Offered Price"). Upon the request of the Company, the Seller will
promptly furnish information to the Company as may be reasonably requested to
establish that the offer and proposed transferee are bona fide.

               3.2 RIGHT OF FIRST REFUSAL.

                    (a) The Company shall have the right of first refusal to
purchase all or any part of the Offered Stock, if the Company gives written
notice of the exercise of such right to the Seller within thirty (30) days (the
"Company's Refusal Period") after the date of the Seller's Notice to the
Company, provided however, that for purposes of this Section 3.2, Offered Stock
shall not include proposed transfers of stock to any Transferee who is either
(i) a partner or affiliate of the Seller or (ii) a corporation or limited
liability company which is an Affiliate of the Seller.




                                      -21-
<PAGE>   22

                    (b) The purchase price for the Offered Stock to be purchased
by the Company exercising its right of first refusal under this Agreement will
be the Offered Price, and will be payable as set forth in Section 3.2(c) hereof.
If the Offered Price includes consideration other than cash, the cash equivalent
value of the non-cash consideration will be determined by the Board of Directors
of the Company in good faith, which determination will be binding upon the
Company and the Seller, absent fraud or error.

                    (c) Payment of the purchase price for the Offered Stock
purchased by the Company exercising its right of first refusal will be made
within fifteen (15) days after the end of the Company's Refusal Period. Payment
of the purchase price will be made, at the option of the Company (i) in cash (by
check), (ii) by cancellation of all or a portion of any outstanding indebtedness
of the Seller to the Company, or (iii) by any combination of the foregoing.

                    (d) If the Company exercises its right of first refusal to
purchase the Offered Stock, then, upon the date the notice of such exercise is
given by the Company, the Seller will have no further rights as a holder of the
Offered Stock except the right to receive payment for the Offered Stock from the
Company in accordance with the terms of this Agreement and the Seller will
forthwith cause all certificate(s) evidencing such Offered Stock to be
surrendered for transfer to the Company.

                    (e) The right of the Company to purchase any part of the
Offered Stock may be assigned in whole or in part to any third party in the
Company's sole discretion.

                    (f) If the Company (or its designated assignee) has not
elected to purchase all of the Offered Stock, then the Seller may transfer the
remaining shares of Offered Stock to the Transferee at the Offered Price or at a
higher price, provided that such transfer (i) is consummated within thirty (30)
days after the end of the Company's Refusal Period, (ii) is on terms no more
favorable than the terms proposed in the Seller's Notice and (iii) is in
accordance with all the terms of this Agreement. If the Offered Stock is not so
transferred during such thirty (30) day period, then the Seller may not transfer
any of such Offered Stock without complying again in full with the provisions of
this Agreement.

               3.3 RESTRICTIVE LEGEND AND STOP-TRANSFER ORDERS.

                    (a) Each Investor understands and agrees that the Company
will cause the legend set forth below, or a legend substantially equivalent
thereto, to be placed upon any certificate(s) or other documents or instruments
evidencing ownership of the Registrable Securities:

        THE SHARES REPRESENTED BY THIS CERTIFICATE ARE SUBJECT TO CERTAIN RIGHTS
        OF FIRST REFUSAL AS SET FORTH IN AN AGREEMENT ENTERED INTO BY THE HOLDER
        OF THESE SHARES AND THE COMPANY. A COPY OF SUCH AGREEMENT IS ON FILE AT
        THE PRINCIPAL OFFICE OF THE COMPANY. SUCH RIGHTS OF FIRST REFUSAL ARE
        BINDING ON CERTAIN TRANSFEREES OF THESE SHARES.



                                      -22-
<PAGE>   23

                    (b) Each Investor agrees, to ensure compliance with the
restrictions referred to herein, that the Company may issue appropriate "stop
transfer" certificates or instructions and that, if the Company transfers its
own securities, it may make appropriate notations to the same effect in its
records.

               3.4 TRANSFERS. No securities shall be transferred unless (i) such
transfer is made in compliance with applicable federal and state securities laws
and (ii) prior to such transfer, the transferees sign a counterpart to this
Agreement pursuant to which it or they agree to be bound by the terms of this
Agreement. The Company shall not be required (a) to transfer on its books any
shares that shall have been sold or transferred in violation of any of the
provisions of this Agreement or (b) to treat as the owner of such shares or to
accord the right to vote as such owner or to pay dividends to any transferee to
whom such shares shall have been so transferred.

               3.5 TERMINATION OF RIGHT OF FIRST REFUSAL. The Company's right of
first refusal pursuant to Section 3.2 hereof shall terminate immediately prior
to the closing of: (i) a Qualified IPO or (ii) the sale, conveyance, disposal,
or encumbrance of all or substantially all of the Company's property or business
or the Company's merger into or consolidation with any other corporation (other
than a wholly-owned subsidiary corporation) or any other transaction or series
of related transactions in which more than fifty percent (50%) of the voting
power of the Company is disposed of, provided that this Section 3.5 shall not
apply to a merger effected exclusively for the purpose of changing the domicile
of the Company.

        4. COVENANTS OF AMAZON.COM. Amazon.com hereby covenants and agrees as
follows:

               4.1 LIMITATION ON OWNERSHIP. Except with the prior written
consent of a majority of the Company's Board of Directors (excluding the vote of
any director designated by Amazon.com), Amazon.com shall not, directly or
indirectly, acquire beneficial ownership of any capital stock of the Company,
any securities convertible into or exchangeable for capital stock of the
Company, or any other right to acquire capital stock of the Company (except, in
any case, by way of stock dividends or other distributions or offerings made
available to holders of any capital stock generally) if the effect of such
acquisition would be to increase the capital stock owned by Amazon.com to more
than the Threshold Percentage; provided, however, that Amazon.com may acquire
additional shares of capital stock of the Company without regard to the
foregoing limitation upon the earliest to occur of the following (the
"Standstill Termination Date"):

                    (a) the second anniversary of the closing date of a
Qualified IPO;

                    (b) immediately following the effective date on which the
Company shall sell, convey, or otherwise dispose of or encumber all or
substantially all of its property or business or merge or consolidate with any
other corporation (other than a wholly-owned subsidiary corporation) or effect
any other transaction or series of related transactions in which more than fifty
percent (50%) of the voting power of the Company is disposed of, except in each
case a merger effected exclusively for the purpose of changing the domicile of
the Company; or

                    (c) April 22, 2003.




                                      -23-
<PAGE>   24

Notwithstanding the foregoing, if the Company repurchases or recapitalizes any
of its shares and such repurchases or recapitalization result in Amazon.com
owning more than the Threshold Percentage at the effective time of such
repurchases or recapitalization, Amazon.com shall not be obligated to divest
itself of shares of capital stock of the Company to meet the foregoing the
Threshold Percentage, but shall not acquire any additional shares of capital
stock of the Company unless such acquisition would otherwise be permitted under
this Section 4.1

               4.2 NOTICE OF CAPITAL STOCK PURCHASES. Amazon.com shall notify
the Company as to any future acquisition of beneficial ownership of capital
stock, or rights thereto, within ten (10) business days after such action in
order for the Company to monitor compliance with the terms of this Agreement.
All purchases of capital stock of the Company by Amazon.com shall be made in
compliance with applicable laws and regulations.

               4.3 ACQUISITION BY POOLING. In the event the Company enters into
any agreement providing for the acquisition of the Company by merger, sale of
assets or otherwise in a negotiated transaction approved by the Board of
Directors of the Company, then if such agreement provides, as a condition to
closing, that the transaction shall be treated as a pooling of interests under
generally accepted accounting principles, Amazon.com shall (i) refrain from
exercising any right of appraisal; and (ii) not sell or otherwise reduce its
risk relative to any securities received in such combination until such time as
financial results covering at least 30 days of post-transaction combined
operations have been published.

               4.4 PERMITTED TRANSACTION. Notwithstanding the provisions of this
Section 4, on and after the eleventh business day after the commencement of a
proxy contest, tender offer or exchange offer which could result in a "Change of
Control Transaction" (as defined below) for the outstanding shares of capital
stock of the Company or on or after the public announcement that the Company has
entered into an agreement with a third party not affiliated with the Company
that would result in a Change of Control Transaction, Amazon.com shall be
permitted to make a proposal to the Company's Board of Directors or shareholders
or to tender or exchange shares of capital stock beneficially owned by it
pursuant to such transaction. As used herein, "Change of Control Transaction"
shall mean (a) any tender or exchange offer, merger, consolidation,
recapitalization or other business combination or transaction pursuant to which
either (1) the holders of the outstanding voting power immediately prior to the
transaction would hold less than 50% of the outstanding voting power outstanding
immediately after the transaction or (2) 50% of the assets of the Company would
be transferred to or controlled by a third party not affiliated with the
Company, excluding in each case a merger effected exclusively for the purpose of
changing the domicile of the Company, or (b) any action by the shareholders of
the Company that results in the directors, who as of the date of Closing
constitute the Company's Board of Directors (the "Incumbent Board"), ceasing to
constitute at least a majority of the Company's Board of Directors; provided,
however that any individual becoming a director subsequent to the date of
Closing whose nomination for election by the shareholders of the Company was
approved by the vote of the Incumbent Board shall be considered as though such
individual were a member of the Incumbent Board.

        5. MISCELLANEOUS.


                                      -24-
<PAGE>   25

               5.1 SUCCESSORS AND ASSIGNS. Except as otherwise provided in this
Agreement, the terms and conditions of this Agreement shall inure to the benefit
of and be binding upon the respective permitted successors and assigns of the
parties (including transferees of any of the Series A Preferred Stock, Series B
Preferred Stock, Series C Preferred Stock or any Common Stock issued upon
conversion thereof). Subject to the threshold provisions generally included
above herein, the parties agree that the Investors may assign their rights and
obligations under this Agreement to any of their current or former partners,
members or affiliates, including to any corporation or limited liability company
which is an Affiliate of such Investor. Nothing in this Agreement, express or
implied, is intended to confer upon any party other than the parties hereto or
their respective successors and assigns any rights, remedies, obligations, or
liabilities under or by reason of this Agreement, except as expressly provided
in this Agreement.

               5.2 AMENDMENTS AND WAIVERS. This Agreement (including the Exhibit
hereto) constitutes the full and entire understanding and agreement among the
parties with regard to the subjects hereof and supersedes and terminates in its
entirety the Investors' Rights Agreement dated as of November 5, 1999. Any term
of this Agreement may be amended or waived (either generally or in a particular
instance and either retroactively or prospectively) only with the written
consent of the Company and the holders of at least seventy percent (70%) of the
Registable Securities then outstanding, not including the Founders' Stock;
provided that if such amendment has the effect of affecting the Founders' Stock
(i) in a manner different than securities issued to the Investors and (ii) in a
manner adverse to the interests of the holders of the Founders' Stock, then such
amendment shall also require the consent of the holder or holders of a majority
of the Founders' Stock. Any amendment or waiver effected in accordance with this
paragraph shall be binding upon each holder of any Registrable Securities then
outstanding, each future holder of all such Registrable Securities, and the
Company. Notwithstanding the foregoing, this Agreement (including Exhibit A
hereto) (i) may be amended with only the written consent of the Company to
include additional purchasers of Series C Preferred Stock as "Investors" or
"Holders," and (ii) may not be amended without the consent of the Holders of at
least 75% of the Series C Preferred Stock (and the Common Stock converted
therefrom) then outstanding if such amendment impairs, dilutes or otherwise
negatively affects the rights of such Holders in a manner different than the
other Holders, except for any amendment which impairs, dilutes or otherwise
negatively affects the rights of the Holders of the Series C Preferred Stock
(and the Common Stock converted therefrom) under Section 1.3, in which case such
Section 1.3 shall not be so amended without the consent of the Holders of at
least 75% of the Series C Preferred Stock (and the Common Stock converted
therefrom) then outstanding.

               5.3 NOTICES. Unless otherwise provided, any notice required or
permitted by this Agreement shall be in writing and shall be deemed sufficient
upon delivery, when delivered personally or by overnight courier or sent by fax
(with confirmation of successful electronic transmission), or forty-eight (48)
hours after being deposited in the U.S. mail, as certified or registered mail,
with postage prepaid, and addressed to the party (with a copy to such party's
counsel at such counsel's address or fax number as set forth in the Purchase
Agreement or the Prior Purchase Agreement, whichever applicable) to be notified
at such party's address or fax number as set forth on the signature page or on
Exhibit A hereto or as subsequently modified by written notice.


                                      -25-
<PAGE>   26

               5.4 SEVERABILITY. If one or more provisions of this Agreement are
held to be unenforceable under applicable law, the parties agree to renegotiate
such provision in good faith. In the event that the parties cannot reach a
mutually agreeable and enforceable replacement for such provision, then (a) such
provision shall be excluded from this Agreement, (b) the balance of the
Agreement shall be interpreted as if such provision were so excluded and (c) the
balance of the Agreement shall be enforceable in accordance with its terms.

               5.5 GOVERNING LAW. This Agreement and all acts and transactions
pursuant hereto shall be governed, construed and interpreted in accordance with
the laws of the State of California, without giving effect to principles of
conflicts of laws.

               5.6 COUNTERPARTS. This Agreement may be executed in two or more
counterparts, each of which shall be deemed an original, but all of which
together shall constitute one and the same instrument.

               5.7 TITLES AND SUBTITLES. The titles and subtitles used in this
Agreement are used for convenience only and are not to be considered in
construing or interpreting this Agreement.

               5.8 AGGREGATION OF STOCK. All shares of the Preferred Stock held
or acquired by affiliated entities or persons shall be aggregated together for
the purpose of determining the availability of any rights under this Agreement.

               5.9 EXPENSES. If any action at law or in equity is necessary to
enforce or interpret the terms of this Agreement, the prevailing party shall be
entitled to reasonable attorneys' fees, costs and necessary disbursements in
addition to any other relief to which such party may be entitled.

               5.10 WAIVERS.

                    (a) WAIVER OF RIGHT OF FIRST OFFER IN PRIOR RIGHTS
AGREEMENT. By executing this Agreement, the undersigned agrees that it hereby
waives on behalf of itself and all other Investors (as defined in the Prior
Rights Agreement) the right of first offer contained in Section 2.3 of the Prior
Rights Agreement to purchase the Series C Shares to which such Investors would
otherwise be entitled.

                    (b) WAIVER OF NOTICE AND PIGGYBACK REGISTRATION RIGHTS AND
RIGHT OF FIRST OFFER. By executing this Agreement, Amazon.com and the
undersigned entities affiliated with Hummer Winblad Venture Partners and Bowman
Capital agree that each hereby waives its respective rights: (i) to receive
notice of the Company's initial public offering ("IPO") pursuant to section 1.3
herein above and (ii) to request inclusion of its Registrable Securities for
registration and sale in such IPO, provided that the Company's registration
statement on Form S-1 in connection with the IPO shall have been declared
effective by the SEC not later than March 31, 2000. The undersigned entities
affiliated with Hummer Winblad Venture Partners and Bowman Capital agree that
the Waiver of Rights Under Amended and Restated Invetors' Rights Agreement
executed by each of them as of November 1999 shall remain in full force and
effect




                                      -26-
<PAGE>   27

and that the reference therein to the Amended and Restated Investors' Rights
Agreement dated as of November 5, 1999 shall refer instead to this Agreement and
any amendments to this Agreement. For clarification, the undersigned entities
affiliated with Bowman Capital further agree that the effect of such waiver is
to prevent such entities from exercising their Right of First Offer under
Section 2.3 to purchase shares in the Company's IPO, provided the Company's IPO
Registration Statement shall have been declared effective by the SEC not later
than March 31, 2000. The undersigned entitled affiliates with Hummer Winblad
Venture Partners and Bowman Capital agree that the failure of any of them to
sign the above referenced waivers shall not invalidate the enforceability of
such waivers by the Company against any of them who has signed the waiver.

               5.11 CONVERSION OF PREFERRED STOCK. The Founders and Investors
agree that within five (5) business days from receipt of written notice by the
Company of its desire to obtain the written consent of holders of Preferred
Stock to convert the shares of Preferred Stock held by them to Common Stock in
connection with an initial offering of the Company's Common Stock, each of the
Founders and Investors shall consent or withhold its consent and inform the
Company of such decision.

               5.12 TERMINATION OF PRIOR RIGHTS AGREEMENT. Upon the execution of
this Agreement by the Company, the Founders and the Investors, the Prior Rights
Agreement shall be amended and restated in its entirety as set forth herein, and
the terms of the Prior Rights Agreement shall be of no further force or effect.

                            [Signature Page Follows]




                                      -27-
<PAGE>   28

        The parties have executed this Amended and Restated Investors' Rights
Agreement as of the date first above written.

                                        COMPANY:

                                        PETS.COM, INC.


                                        By: /s/ Julie Wainwright
                                           -------------------------------------
                                        Name:
                                        Title:
                                        Address: 435 Brannan Street
                                                 San Francisco, CA  94107
                                        Fax:     415-222-9999



                                        FOUNDER:



                                        /s/ Greg McLemore
                                        ----------------------------------------
                                        Greg McLemore
                                        Address: 87 N. Raymond Avenue, Suite 850
                                                 Pasadena, CA  91103
                                        Fax:     626-794-8500

                         SIGNATURE PAGE TO AMENDED AND
                      RESTATED INVESTORS' RIGHTS AGREEMENT


<PAGE>   29

                                        INVESTORS:

                                        CATALYST INVESTMENTS, L.L.C.


                                        By: The Walt Disney Company,
                                            its sole member


                                        By: /s/ Thomas Staggs
                                           -------------------------------------
                                           Thomas O. Staggs
                                           Senior Executive Vice President and
                                           Chief Financial Officer

                                       Address: 500 South Buena Vista Street
                                                Burbank, CA 91521


                                             *
                                        ----------------------------------------
                                        (Investor)

                                        By: /s/ Eric Moore
                                           -------------------------------------
                                        Name:   Eric Moore
                                             -----------------------------------
                                                          (print)
                                        Title:  Controller
                                              ----------------------------------
                                        *
                                        SPINNAKER TECHNOLOGY FUND LP SPINNAKER
                                        TECHNOLOGY
                                             OFFSHORE FUND LTD.
                                        SPINNAKER FOUNDERS FUND, LP
                                        SPINNAKER OFFSHORE FOUNDERS
                                              FUND LTD
                                        SPINNAKER CLIPPER FUND, LP




                                        AMAZON.COM, INC.
                                        ----------------------------------------
                                        (Investor)

                                        By: /s/ Mark Britto

                                        Name: Mark Britto
                                             -----------------------------------
                                                          (print)
                                        Title: VP
                                              ----------------------------------

                         SIGNATURE PAGE TO AMENDED AND
                      RESTATED INVESTORS' RIGHTS AGREEMENT
<PAGE>   30

                                       HUMMER WINBLAD VENTURE PARTNERS III, L.P.
                                       HUMMER WINBLAD TECHNOLOGY FUND III, L.P.
                                       HUMMER WINBLAD VENTURE PARTNERS IV, L.P.

                                       By: /s/ John Hummer
                                          -------------------------------------
                                       Name: John Hummer
                                            -----------------------------------
                                                         (print)
                                       Title: Member
                                             ----------------------------------


                                      -2-