<PAGE>

                                                          CONFIDENTIAL TREATMENT
                                                       REQUESTED UNDER 17 C.F.R.
                                                     SECTIONS 200.83 AND 230.496



                  AMENDMENT TO STRATEGIC RELATIONSHIP AGREEMENT

         This Amendment (the "Amendment") effective as of April 17, 2001, is
made between Hoover's, Inc., a Delaware corporation ("Hoover's") and
Knowledge Net Holdings, L.L.C., a Delaware corporation ("KU"). The parties
entered into the Strategic Relationship Agreement effective as of June 11,
1999 (the "Strategic Relationship Agreement"). [Capitalized terms not otherwise
defined herein shall be defined as in the Strategic Relationship Agreement]
 . Upon execution by both parties of this Amendment, this Amendment will
constitute the binding agreement of Hoover's and KU. Hoover's and KU agree as
follows:

1.       BACKGROUND

         In connection with the purchase of common stock of Hoover's by KU, the
         parties entered into the Strategic Relationship Agreement to provide
         for the purchase from Hoover's by KU and its Affiliates of Services
         totaling $2.0 million through September 30, 2001. To date, KU has made
         payments totaling [*] under the Strategic Relationship Agreement, with
         remaining obligations of [*]. The parties desire to amend the Agreement
         to provide that, in addition to the purchase of services by KU and its
         Affiliates, KU may: (i) satisfy the Spending Requirement through the
         Referral of business opportunities to Hoover's; (ii) extend the period
         for satisfaction of the Spending Requirement through [*] and (iii)
         establish procedures to document KU's good faith efforts to satisfy the
         Spending Requirement.

2.       AMENDMENTS

         The Strategic Relationship Agreement is hereby amended as follows:

         (a)  Section 1(a) is hereby amended to provide that KU will satisfy the
              remaining Spending Requirement of [*] prior to [*] through the
              purchase of Services or through Referrals. KU will use its good
              faith efforts to satisfy the Spending Requirements in equal
              increments over the remaining [*] of the term of the Strategic
              Relationship Agreement. KU will appoint a liaison for coordinating
              KU's efforts to satisfy its Spending Requirement obligations and
              communicating these efforts to Hoover's. KU will provide a written
              report detailing these efforts no later than fifteen (15) days
              following the end of each calendar quarter during the term,
              beginning on July 15, 2001. [*].

         (b)  Section 1(g) is hereby added as follows:

              "For the purposes of this Agreement, `Referrals' shall mean all
         revenue generated by Hoover's from the sale of its services, including
         without limitation subscription-based products or advertising, on an
         arms-length basis that result directly from contacts referred to
         Hoover's by KU or its Affiliates, as documented on the quarterly
         reports provided by KU as described in Section 1(a). In the event that
         Hoover's completes an arms-length sale to an entity for which KU
         believes it is entitled to credit that has not been documented on a
         previous quarterly report, KU may provide evidence of its or an
         Affiliate's contact with such customer and Hoover's will consider such
         evidence and credit KU for such sale against the Spending Requirements
         as warranted. For purposes of this provision, all revenue generated by
         Hoover's from [*] and [*] shall be deemed to have resulted from direct
         referral by KU."

         (c)  Section 4 is hereby amended to provide that the term of the
              Strategic Relationship Agreement shall continue through [*], or as
              further extended in accordance with Section 1(a) of the Strategic
              Relationship Agreement and Section 2(a) above.

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[*] Indicates that material has been omitted and confidential treatment
requested therefor. All such material has been filed separately with the
Commission pursuant to Rule 406.

<PAGE>
                                                          CONFIDENTIAL TREATMENT
                                                       REQUESTED UNDER 17 C.F.R.
                                                     SECTIONS 200.83 AND 230.496

         (d)  Section 21 is hereby added as follows:

              "21. INDEMNIFICATION. KU hereby indemnifies Hoover's against any
              liabilities, losses, claims or damages (including reasonable legal
              costs) which may be awarded or agreed to be paid to any KU
              Affiliate in respect of any claim alleging that the Services
              provided through the date of this Amendment by Hoover's to KU and
              its Affiliates, for which KU and its Affiliates have paid a total
              of [*], did not conform to specifications or violated any express
              or implied warranty of Hoover's with respect thereto, provided
              that:

                  (a)      Hoover's gives written notice to KU of any claim
                           immediately on becoming aware thereof and does not at
                           any time admit liability or otherwise attempt to
                           settle or compromise such claim except on the express
                           written instructions of KU;

                  (b)      KU shall have sole conduct of the defense or
                           compromise of any claim; and

                  (c)      Hoover's acts in accordance with the reasonable
                           instructions of KU and gives KU such assistance as it
                           shall reasonably require in respect of the conduct of
                           such defense or compromise (and KU shall reimburse
                           Hoover's its reasonable costs incurred in complying
                           with the provisions of this Section 21(c))."

 3.      EFFECT

         This Amendment will become effective as of April 17, 2001. The
         provisions of this Amendment will control over any inconsistent
         provisions of the Strategic Relationship Agreement. Except as
         specifically amended hereby, the terms of the Strategic Relationship
         Agreement shall remain in full force and effect. The provisions of this
         Amendment constitute confidential information of the parties and may
         not be disclosed without prior written consent of the parties hereto
         (except to the extent required by applicable law). The parties will not
         be bound by any modifications made to this Amendment unless
         specifically consented to in a writing signed by both parties.


         By signature below, the parties agree to the terms and conditions of
         this Amendment as of the date written below.

                                             HOOVER'S, INC.

                                             By:     ___________________________

                                             Title:  ___________________________

                                             Date:  ____________________________

                                             KNOWLEDGE NET HOLDINGS, L.L.C.

                                             By:     ___________________________

                                             Title:  ___________________________

                                             Date:  ____________________________


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[*] Indicates that material has been omitted and confidential treatment
requested therefor. All such material has been filed separately with the
Commission pursuant to Rule 406.