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                                                              Exhibit 10.15(b)


                             PAPEREXCHANGE.COM, INC.

                           2000 EQUITY INCENTIVE PLAN

                             STOCK OPTION AGREEMENT
                                OPTION NO: _____

      THIS AGREEMENT dated as of _________________ ___, 2000, between
PaperExchange.com, Inc., a corporation organized under the laws of the State of
Delaware (the "Company"), and the individual identified below, residing at the
address there set out (the "Optionee").

      1. Grant of Option. Pursuant and subject to the Company's 2000 Equity
Incentive Plan as attached hereto (the "Plan"), the Company grants to the
Optionee an option (the "Option") to purchase from the Company all or any part
of a total of ________________ shares (the "Optioned Shares") of the common
stock, par value $.001 per share, in the Company (the "Stock"), at a price, of
$ ______________ per share. This Option is granted(1) as of _______________ ___,
20__ (the "Grant Date").

      2. Character of Option. This Option ____________ (2) to be treated as an
"incentive stock option" within the meaning of Section 422 of the Internal
Revenue Code of 1986, as amended.

      3. Duration of Option. This Option shall expire at 5:00 p.m. on the
earlier of

            (a) the seventh(3) anniversary of the Grant Date, and

            (b) the applicable date below, determined based on the circumstances
in which the Optionee's employment or other association with the Company and its
Affiliates ends (the Optionee's "Termination of Service"):

                  (i) the date of the Optionee's Termination of Service, if by
      the Company or an Affiliate for cause;

                  (ii) the first anniversary of the Optionee's Termination of
      Service, if on account of death or, with the consent of the Company,

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      (1) Replacement options will substitute the word "issued" for the word
"granted" and include the following text: "in full substitution of an option
(the "Replaced Option") previously granted by PaperExchange.com, LLC, the
Company's predecessor, under the PaperExchange.com, LLC 1998 Equity Option
Plan (the "Prior Plan"),". The term "Grant Date" is used to establish the
initial exercise dates, and accordingly for replacement options the date
entered should be the Grant Date of the replaced option.

      (2) Insert "is" or "is not". All replacement options will be "is not".


      (3) Replacement options will expire on the fifth anniversary, rather than
seventh anniversary, to avoid any extension of the options they are intended to
replace. Such an extension may have adverse accounting effects.


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      permanent and total disability (within the meaning of Section 22(e)(3) of
      the Code); and

                  (iii) the 90th day after the Optionee's Termination of
      Service, in any other circumstances.

      4. Exercise of Option. Until its expiration and subject to the remainder
of this Section, this Option may be exercised, in the manner specified in
Section 7.1(f) of the Plan, in those installments of Optioned Shares identified
in the table below, in full or in part, from and after the initial exercise date
set opposite each such installment:

              Number of
        Shares in Installment               Initial Exercise Date
        ---------------------               ---------------------

        One-quarter of the           First anniversary of Grant Date
        Optioned Shares

        1/36th of the remaining      Cumulatively, on the first day of each
        three-quarters of the        month to begin after the first anniversary
        Optioned Shares              of the Grant Date

In the event of the Optionee's Termination of Service by the Company or an
Affiliate other than for cause within twelve (12) months after a change in
control, on such Termination and for the period thereafter the Option remains
exercisable, the Option shall be exercisable to the same extent as it would have
been exercisable had the Optionee remained employed by the Company and its
Affiliates until the first anniversary of the Optionee's Termination of Service
(that is, one additional year's vesting shall be allowed). For this purpose
"change of control" means any transaction, or the initial transaction in a
series of related transactions, occuring after the date hereof if immediately
after such transaction or series more than 50% of the Company's equity
securities have ceased to be owned, directly or indirectly, by persons which
beneficially owned the Company's equity securities, directly or indirectly,
immediately prior to such transaction or series.

         Notwithstanding anything contained herein to the contrary, if this
Option does not otherwise terminate immediately upon the Optionee's Termination
of Service, after such Termination of Service this Option shall, until its
expiration, be exercisable only to the extent exercisable immediately prior to
such Termination. Futhermore, this Option shall in no event be exercisable for a
fractional share, with an fractional share being carried forward to future
installments until a whole share results. Finally, this Option may not be
exercised to any extent unless and until the Optionee has become a party to, and
then only while the Optionee remains bound by the provisions of, the
Stockholders' Agreement.

      5. Transfer of Options. This Option may not be transferred except by will
or the laws of descent and distribution, and, during the lifetime of the
Optionee, may be exercised only by the Optionee.

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      6. Incorporation of Plan Terms. This Option is granted subject to all of
the applicable terms and provisions of the Plan, including but not limited to
the limitations on the Company's obligation to deliver Optioned Shares upon
exercise set forth in Section 9 (Settlement of Awards).

      7.(4) Relationship to Replaced Option; Optionee's Acknowledgement. The
Prior Plan provided that the Optionee would be entitled to exercise the Replaced
Option in full if the conversion of the Company from a limited liability company
into a corporation constituted a reorganization and the Company did not offer
the Optionee an option which substantially preserves the rights and benefits of
the Replaced Option. The Optionee acknowledges and agrees this Option does
substantially preserve the rights and benefits of the Replaced Option. The
Optionee accepts this Option in complete substitution and replacement for the
Replaced Option and all of his or her rights under the Replaced Option and the
Prior Plan, and further agrees upon request of the Company to surrender all
copies of the Replaced Option.

      8. Miscellaneous. This Agreement shall be construed and enforced in
accordance with the laws of the Commonwealth of Massachusetts, without regard to
the conflict of laws principles thereof and shall be binding upon and inure to
the benefit of any successor or assign of the Company and any executor,
administrator, trustee, guardian, or other legal representative of the Optionee.
This Agreement may be executed in two or more counterparts, each of which shall
be an original, but all of which together shall constitute one and the same
instrument. Capitalized terms used but not defined herein shall have the meaning
assigned under the Plan.

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      (4)   Included only in replacement options.

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

PAPEREXCHANGE.COM, INC.


By:   ___________________________    ___________________________________________
Title:___________________________    Signature of Optionee

                                     ___________________________________________
                                     Name of Optionee

                                     Optionee's Address:

                                     ___________________________________________

                                     ___________________________________________

                                     ___________________________________________

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