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                                                                    EXHIBIT 10.2

                                    Exhibit A

                                LOCK-UP AGREEMENT


                                 March ___, 2000


eGroups, Inc.
350 Brannan Street
San Francisco, CA 94107

Donaldson, Lufkin & Jenrette Securities Corporation
Chase Securities Inc.
FleetBoston Robertson Stephens Inc.
         c/o Donaldson, Lufkin & Jenrette Securities Corporation
         277 Park Avenue
         New York, New York  10172


Ladies and Gentlemen:

The undersigned understands that Donaldson, Lufkin & Jenrette Securities
Corporation, Chase Securities, Inc. and FleetBoston Robertson Stephens Inc., as
Representatives of the several underwriters (the "UNDERWRITERS"), propose to
enter into an Underwriting Agreement with eGroups, Inc. (the "COMPANY"),
providing for the initial public offering (the "INITIAL PUBLIC OFFERING") of
common stock, par value $.001 per share (the "COMMON STOCK"), of the Company.

To induce the Underwriters that may participate in the Initial Public Offering
to continue their efforts in connection with the Initial Public Offering, the
undersigned, form the date hereof and through the end of the 180-day period
after the date of the final prospectus relating to the Initial Public Offering
(the "FINAL PROSPECTUS"):

        (i)   agrees not to (x) offer , pledge, sell, contract to sell, sell any
              option or contract to purchase, purchase any option or contract to
              sell, grant any option, right or warrant to purchase, other wise
              transfer or dispose of, directly or indirectly, any shares of
              Common Stock (other than shares of common stock purchased in the
              open market by the undersigned on or after the closing of the
              Initial Public Offering) or any securities convertible into or
              exercisable or exchangeable for Common Stock (including, without
              limitation, shares of Common Stock or securities convertible into
              or exercisable or exchangeable for Common Stock which may be
              deemed to be beneficially owned by the undersigned in accordance
              with the rules and regulations of the Securities and Exchange

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              Commission) (collectively, "COMPANY SECURITIES") or (y) enter into
              any swap or other arrangement that transfers all or a portion of
              the economic consequences associated with the ownership of any
              Company Securities (regardless of whether any of the transactions
              described in clause (x) or (y) is to be settled by the delivery of
              Company Securities, in cash or otherwise), without the prior
              written consent of Donaldson, Lufkin & Jenrette Securities
              Corporation;

        (ii)  agrees not to make any demand for, or exercise any right with
              respect to, the registration of any Company Securities, without
              the prior written consent of Donaldson, Lufkin & Jenrette
              Securities Corporation; and

        (iii) authorizes the Company to cause the transfer agent to decline to
              transfer and/or to note stop transfer restrictions on the transfer
              books and records of the Company with respect to any Company
              Securities for which the undersigned is the record holder and, in
              the case of any such shares or securities for which the
              undersigned is the beneficial but not the record holder, agrees to
              cause the record holder to cause the transfer agent to decline to
              transfer and/or to note stop transfer restrictions on such books
              and records with respect to such shares or securities;

provided further, that the restrictions in clause (i) above shall cease to apply
to (A) 25% of the Company Securities beneficially owned by the undersigned on
the date of the Final Prospectus upon the later to occur of (I) the end of the
90-day period after the date of the Final Prospectus or (II) the second trading
day following the first public release of the Company's quarterly results after
the date of the Final Prospectus, and (B) an additional 25% of the Company
Securities beneficially owned by the undersigned on the date of the Final
Prospectus, upon the end of the 135-day period after the date of the Final
Prospectus if, in the case of both clauses (A) and (B), (X) the reported last
sale price of the Common Stock on the Nasdaq National Market is at least twice
the price per share in the Initial Public Offering for 20 of the 30 trading days
ending on (a) in the case of clause (A) above, the later of (1) the last trading
day of the 90-day period after the date of the Final Prospectus or (2) the
second trading day following the first public release of the Company's quarterly
results after the date of the Final Prospectus and (b) in the case of clause (B)
above, the last trading day of the 135-day period after the date of the Final
Prospectus and (Y) the undersigned is not, and has not been since the date of
the Final Prospectus, an officer of the Company; provided further , that the
undersigned agrees to give Donaldson, Lufkin & Jenrette Securities Corporation
and the Company written notice three business days prior to taking any of the
actions set forth in clause (i) above pursuant to the preceding proviso and to
execute any such action only through Donaldson, Lufkin & Jenrette Securities
Corporation or any of its affiliates acting as broker, unless otherwise agreed
in writing by of Donaldson, Lufkin & Jenrette Securities Corporation.

The undersigned hereby represents and warrants that the undersigned has full
power and authority to enter into the agreements set forth herein, and that,
upon request, the undersigned will execute any additional documents necessary or
desirable in connection with the enforcement

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hereof. All authority herein conferred or agreed to be conferred shall survive
the death or incapacity of the undersigned and any obligations of the
undersigned shall be binding upon the heirs, personal representatives,
successors, and assigns of the undersigned.

                                            Very truly yours,



                                            ------------------------------------
                                            Name: (Please Print or type)
                                                  Address:


Social Security or Taxpayer Identification No.:

Number of shares of Common Stock owned:




Number and name of securities that are convertible into, or exercisable or
exchangeable for, Common Stock:







Number of shares of Common Stock issuable upon conversion, exercise or exchange
of such securities: