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                                                                     Exhibit 4.2

                            INFORMATION HOLDINGS INC.

                          REGISTRATION RIGHTS AGREEMENT

     REGISTRATION RIGHTS AGREEMENT, dated as of August 12, 1998, among the
investors listed on Schedule I hereto (the "Investors") and Information Holdings
Inc., a Delaware corporation (the "Company").

                              W I T N E S S E T H:

     WHEREAS, the Investors or their affiliates are party to a Registration
Rights Agreement, dated December 2, 1996, with respect to equity interests in
Information Ventures LLC, a Delaware limited liability company ("Interests");

     WHEREAS, pursuant to the terms of the Exchange Agreement, dated as June 10,
1998, among the Company and the Investors and other parties named therein (the
"Exchange Agreement"), the Investors agreed to exchange their Interests for
shares of common stock, par value $.01, of the Company ("Common Stock"); and

     WHEREAS, pursuant to Section 2.1 of the Exchange Agreement, the Company and
the Investors desire to define the registration rights of the Investors on the
terms and subject to the conditions herein set forth.

     NOW, THEREFORE, in consideration of the foregoing premises and for other
good and valuable consideration, the parties hereby agree as follows:

     1. DEFINITIONS

     As used in this Agreement, the following terms have the respective meaning
set forth below:

     COMMISSION: shall mean the Securities and Exchange Commission or any other
federal agency at the time administering the Securities Act;

     EXCHANGE ACT: shall mean the Securities Exchange Act of 1934, as amended;

     HOLDER: shall mean any holder of Registrable Securities;

     INITIATING HOLDER: shall mean any Holder or Holders who in the aggregate
are Holders of more than 50% of the then outstanding Registrable Securities;

     PERSON: shall mean an individual, partnership, joint-stock company,
corporation, trust or unincorporated organization, and a government or agency or
political subdivision thereof;

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     REGISTER, REGISTERED and REGISTRATION: shall mean to a registration
effected by preparing and filing a registration statement in compliance with the
Securities Act (and any post-effective amendments filed or required to be filed)
and the declaration or ordering of effectiveness of such registration statement;

     REGISTRABLE SECURITIES: shall mean (A) shares of Common Stock acquired
pursuant to the Exchange Agreement, (B) any additional shares of Common Stock
acquired by the Investors and (C) any capital stock of the Company (or any
successor to the Company) issued as a dividend or other distribution with
respect to, or in exchange for or in replacement of, the shares of Common Stock
referred to in clause (A), (B) or (C);

     REGISTRATION EXPENSES: shall mean all expenses incurred by the Company in
compliance with Sections 2(a) and (b) hereof, including, without limitation, all
registration and filing fees, printing expenses, fees and disbursements of
counsel for the Company, fees and expenses of one counsel for all the Holders in
an amount not to exceed $15,000, blue sky fees and expenses and the expense of
any special audits incident to or required by any such registration (but
excluding the compensation of regular employees of the Company, which shall be
paid in any event by the Company);

     SECURITY, SECURITIES: shall have the meaning set forth in Section 2(1) of
the Securities Act;

     SECURITIES ACT: shall mean the Securities Act of 1933, as amended; and

     SELLING EXPENSES: shall mean all underwriting discounts and selling
commissions applicable to the sale of Registrable Securities and all fees and
disbursements of counsel for each of the Holders other than fees and expenses of
one counsel for all the Holders in an amount not to exceed $15,000.

     2. REGISTRATION RIGHTS

     (a) Requested Registration.

          (i) REQUEST FOR REGISTRATION. If the Company shall receive from an
     Initiating Holder, at any time, a written request that the Company effect
     any registration with respect to all or a part of the Registrable
     Securities, the Company will:

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

               (B) as soon as practicable, use its diligent best efforts to
          effect such registration (including,

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          without limitation, the execution of an undertaking to file
          post-effective amendments, appropriate qualification under applicable
          blue sky or other state securities laws and appropriate compliance
          with applicable regulations issued under the Securities Act) as may be
          so requested and as would permit or facilitate the sale and
          distribution of all or such portion of such Registrable Securities as
          are specified in such request, together with all or such portion of
          the Registrable Securities of any Holder or Holders joining in such
          request as are specified in a written request received by the Company
          within 10 business days after written notice from the Company is given
          under Section 2(a)(i)(A) above; PROVIDED that the Company shall not be
          obligated to effect, or take any action to effect, any such
          registration pursuant to this Section 2(a):

                    (x) In any particular jurisdiction in which the Company
               would be required to execute a general consent to service of
               process in effecting such registration, qualification or
               compliance, unless the Company is already subject to service in
               such jurisdiction and except as may be required by the Securities
               Act or applicable rules or regulations thereunder;

                    (y) After the Company has effected two (2) such
               registrations pursuant to this Section 2(a) and such
               registrations have been declared or ordered effective and the
               sales of such Registrable Securities shall have closed; or

                    (z) If the Registrable Securities requested by all Holders
               to be registered pursuant to such request do not have an
               anticipated aggregate public offering price (before any
               underwriting discounts and commissions) of not less than
               $15,000,000.

     The registration statement filed pursuant to the request of the Initiating
Holders may, subject to the provisions of Section 2(a)(ii) below, include other
securities of the Company which are held by Persons who, by virtue of agreements
with the Company, are entitled to include their securities in any such
registration ("Other Stockholders").

     The registration rights set forth in this Section 2 may be assigned, in
whole or in part, to any transferee of Registrable Securities (who shall be
bound by all obligations of this Agreement).

               (ii) UNDERWRITING. If the Initiating Holders intend to distribute
          the Registrable Securities covered by 


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          their request by means of an underwriting, they shall so advise the
          Company as a part of their request made pursuant to Section 2(a).

     If Other Stockholders request such inclusion, the Holders shall offer to
include the securities of such Other Stockholders in the underwriting and may
condition such offer on their acceptance of the further applicable provisions of
this Section 2. The Holders whose shares are to be included in such registration
and the Company shall (together with all Other Stockholders proposing to
distribute their securities through such underwriting) enter into an
underwriting agreement in customary form with the representative of the
underwriter or underwriters selected for such underwriting by the Initiating
Holders and reasonably acceptable to the Company. Notwithstanding any other
provision of this Section 2(a), if the representative advises the Holders in
writing that marketing factors require a limitation on the number of shares to
be underwritten, the securities of the Company held by Other Stockholders shall
be excluded from such registration to the extent so required by such limitation.
If, after the exclusion of such shares, further reductions are still required,
the number of shares included in the registration by each Holder shall be
reduced on a pro rata basis (based on the number of shares held by such Holder),
by such minimum number of shares as is necessary to comply with such request. No
Registrable Securities or any other securities excluded from the underwriting by
reason of the underwriter's marketing limitation shall be included in such
registration. If any Other Stockholder who has requested inclusion in such
registration as provided above disapproves of the terms of the underwriting,
such person may elect to withdraw therefrom by written notice to the Company,
the underwriter and the Initiating Holders. The securities so withdrawn shall
also be withdrawn from registration. If the underwriter has not limited the
number of Registrable Securities or other securities to be underwritten, the
Company and officers and directors of the Company may include its or their
securities for its or their own account in such registration if the
representative so agrees and if the number of Registrable Securities and other
securities which would otherwise have been included in such registration and
underwriting will not thereby be limited.

          (b) COMPANY REGISTRATION.

               (i) If the Company shall determine to register any of its equity
          securities either for its own account or for the account of Other
          Stockholders, other than a registration relating solely to employee
          benefit plans, or a registration relating solely to a Commission Rule
          145 transaction, or a registration on any registration form which does
          not permit secondary sales or does not include substantially the same
          information as would be required to be included in a registration
          statement covering the sale of Registrable Securities, the Company
          will:


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                    (A) promptly give to each of the Holders a written notice
               thereof (which shall include a list of the jurisdictions in which
               the Company intends to attempt to qualify such securities under
               the applicable blue sky or other state securities laws); and

                    (B) include in such registration (and any related
               qualification under blue sky laws or other compliance), and in
               any underwriting involved therein, all the Registrable Securities
               specified in a written request or requests, made by the Holders
               within fifteen (15) days after receipt of the written notice from
               the Company described in clause (i) above, except as set forth in
               Section 2(b)(ii) below. Such written request may specify all or a
               part of the Holders' Registrable Securities.

               (ii) UNDERWRITING. If the registration of which the Company gives
          notice is for a registered public offering involving an underwriting,
          the Company shall so advise each of the Holders as a part of the
          written notice given pursuant to Section 2(b)(i)(A). In such event,
          the right of each of the Holders to registration pursuant to this
          Section 2(b) shall be conditioned upon such Holders' participation in
          such underwriting and the inclusion of such Holders' Registrable
          Securities in the underwriting to the extent provided herein. The
          Holders whose shares are to be included in such registration shall
          (together with the Company and the Other Stockholders distributing
          their securities through such underwriting) enter into an underwriting
          agreement in customary form with the representative of the underwriter
          or underwriters selected for underwriting by the Company.
          Notwithstanding any other provision of this Section 2(b), if the
          representative determines that marketing factors require a limitation
          on the number of shares to be underwritten, the representative may
          (subject to the allocation priority set forth below) limit the number
          of Registrable Securities to be included in the registration and
          underwriting to not less than twenty five percent (25%) of the shares
          included therein (based on the number of shares). The Company shall so
          advise all holders of securities requesting registration, and the
          number of shares of securities that are entitled to be included in the
          registration and underwriting shall be allocated in the following
          manner: The securities of the Company held by officers, directors and
          Other Stockholders of the Company (other than Registrable Securities
          and other than securities held by holders who by contractual right
          demanded such registration ("Demanding Holders")) shall be excluded
          from such registration and underwriting to the extent required by such
          limitation, and, if a limitation on the number of shares is still
          required, the number of shares that may be included in the
          registration and underwriting by each of the Holders and Demanding
          Holders shall be reduced, 


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          on a pro rata basis (based on the number of shares held by such
          Holder), by such minimum number of shares as is necessary to comply
          with such limitation. If any of the Holders or any officer, director
          or Other Stockholder disapproves of the terms of any such
          underwriting, he may elect to withdraw therefrom by written notice to
          the Company and the underwriter. Any Registrable Securities or other
          securities excluded or withdrawn from such underwriting shall be
          withdrawn from such registration.

          (c) FORM S-3. The Company shall use its best efforts to qualify for
     registration on Form S-3 for secondary sales. After the Company has
     qualified for the use of Form S-3, the Investors shall have the right to
     request an unlimited number of registrations on Form S-3 (such requests
     shall be in writing and shall state the number of shares of Registrable
     Securities to be disposed of and the intended method of disposition of
     shares by such holders), subject only to the following: 

               (i) The Company shall not be required to effect a registration
          pursuant to this Section 2(c) unless the Holder or Holders requesting
          registration propose to dispose of shares of Registrable Securities
          having an aggregate price to the public (before deduction of
          underwriting discounts and expenses of sale) of more than $5,000,000.

               (ii) The Company shall not be required to effect a registration
          pursuant to this Section 2(c) within 180 days of the effective date of
          the most recent registration pursuant to this Section 2 in which
          securities held by the requesting Holder could have been included for
          sale or distribution.

               (iii) The Company shall not be obligated to effect any
          registration pursuant to this Section 2(c) in any particular
          jurisdiction in which the Company would be required to execute a
          general consent to service of process in effecting such registration,
          qualification or compliance, unless the Company is already subject to
          service in such jurisdiction and except as may be required by the
          Securities Act or applicable rules or regulations thereunder.

     The Company shall give written notice to all Holders of the receipt of a
request for registration pursuant to this Section 2(c) and shall provide a
reasonable opportunity for other Holders to participate in the registration,
provided that if the registration is for an underwritten offering, the terms of
Section 2(a)(ii) shall apply to all participants in such offering. Subject to
the foregoing, the Company will use its best efforts to effect promptly the
registration of all shares of Registrable Securities on Form S-3 to the extent
requested by the Holder or Holders thereof for purposes of disposition.


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          (d) EXPENSES OF REGISTRATION. All Registration Expenses incurred in
     connection with any registration, qualification or compliance pursuant to
     this Section 2 shall be borne by the Company, and all Selling Expenses
     shall be borne by the Holders of the securities so registered pro rata on
     the basis of the number of their shares so registered.

          (e) REGISTRATION PROCEDURES. In the case of each registration effected
     by the Company pursuant to this Section 2, the Company will keep the
     Holders, as applicable, advised in writing as to the initiation of each
     registration and as to the completion thereof. At its expense, the Company
     will:

               (i) keep such registration effective for a period of one hundred
          twenty (120) days or until the Holders, as applicable, have completed
          the distribution described in the registration statement relating
          thereto, whichever first occurs; provided, however, that (A) such
          120-day period shall be extended for a period of time equal to the
          period during which the Holders, as applicable, refrain from selling
          any securities included in such registration in accordance with
          provisions in Section 2(i) hereof; and (B) in the case of any
          registration of Registrable Securities on Form S-3 which are intended
          to be offered on a continuous or delayed basis, such 120-day period
          shall be extended until all such Registrable Securities are sold,
          provided that Rule 415, or any successor rule under the Securities
          Act, permits an offering on a continuous or delayed basis, and
          provided further that applicable rules under the Securities Act
          governing the obligation to file a post-effective amendment permit, in
          lieu of filing a post-effective amendment which (y) includes any
          prospectus required by Section 10(a) of the Securities Act or (z)
          reflects facts or events representing a material or fundamental change
          in the information set forth in the registration statement, the
          incorporation by reference of information required to be included in
          (y) and (z) above to be contained in periodic reports filed pursuant
          to Section 12 or 15(d) of the Exchange Act in the registration
          statement;

               (ii) furnish such number of prospectuses and other documents
          incident thereto as each of the Holders, as applicable, from time to
          time may reasonably request;

               (iii) notify each Holder of Registrable Securities covered by
          such registration at any time when 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

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          statements therein not misleading in the light of the circumstances
          then existing; and

               (iv) furnish, on the date that such Registrable Securities are
          delivered to the underwriters for sale, 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, (1) an opinion, dated as
          of 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 and reasonably
          satisfactory to a majority in interest of the Holders participating in
          such registration, addressed to the underwriters, if any, and to the
          Holders participating in such registration and (2) a letter, dated as
          of 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 and reasonably satisfactory to a majority in interest of the
          Holders participating in such registration, addressed to the
          underwriters, if any, and if permitted by applicable accounting
          standards, to the Holders participating in such registration.

          (f) INDEMNIFICATION.

               (i) The Company will indemnify each of the Holders, as
          applicable, each of its officers, directors and partners, and each
          person controlling each of the Holders, with respect to each
          registration which has been effected pursuant to this Section 2, and
          each underwriter, if any, and each person who controls any
          underwriter, against all claims, losses, damages and liabilities (or
          actions in respect thereof) arising out of or based on any untrue
          statement (or alleged untrue statement) of a material fact contained
          in any prospectus, offering circular or other document (including any
          related registration statement, notification or the like) incident to
          any such registration, qualification or compliance, or based on any
          omission (or alleged omission) to state therein a material fact
          required to be stated therein or necessary to make the statements
          therein not misleading, or any violation by the Company of the
          Securities Act or the Exchange Act or any rule or regulation
          thereunder applicable to the Company and relating to action or
          inaction required of the Company in connection with any such
          registration, qualification or compliance, and will reimburse each of
          the Holders, each of its officers, directors and partners, and each
          person controlling each of the Holders, each such underwriter and each
          person who controls any such underwriter, for any legal and any other
          expenses reasonably incurred in connection with investigating and
          defending any such claim, loss, damage,


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          liability or action, provided that the Company will not be liable in
          any such case to the extent that any such claim, loss, damage,
          liability or expense arises out of or is based on any untrue statement
          or omission based upon written information furnished to the Company by
          the Holders or underwriter and stated to be specifically for use
          therein.

               (ii) Each of the Holders will, if Registrable Securities held by
          it are included in the securities as to which such registration,
          qualification or compliance is being effected, indemnify the Company,
          each of its directors and officers and each underwriter, if any, of
          the Company's securities covered by such a registration statement,
          each person who controls the Company or such underwriter, each Other
          Stockholder and each of their officers, directors, and partners, and
          each person controlling such Other Stockholder against all claims,
          losses, damages and liabilities (or actions in respect thereof)
          arising out of or based on any untrue statement (or alleged untrue
          statement) of a material fact contained in any such registration
          statement, prospectus, offering circular or other document made by
          such Holder, or any omission (or alleged omission) to state therein a
          material fact required to be stated therein or necessary to make the
          statements by such Holder therein not misleading, and will reimburse
          the Company and such Other Stockholders, directors, officers,
          partners, persons, underwriters or control persons for any legal or
          any other expenses reasonably incurred in connection with
          investigating or defending any such claim, loss, damage, liability or
          action, in each case to the extent, but only to the extent, that such
          untrue statement (or alleged untrue statement) or omission (or alleged
          omission) is made in such registration statement, prospectus, offering
          circular or other document in reliance upon and in conformity with
          written information furnished to the Company by such Holder and stated
          to be specifically for use therein; provided, however, that the
          obligations of each of the Holders hereunder shall be limited to an
          amount equal to the net proceeds to such Holder of securities sold as
          contemplated herein.

               (iii) Each party entitled to indemnification under this Section
          2(f) (the "Indemnified Party") shall give notice to the party required
          to provide indemnification (the "Indemnifying Party") promptly after
          such Indemnified Party has actual knowledge of any claim as to which
          indemnity may be sought, and shall permit the Indemnifying Party to
          assume the defense of any such claim or any litigation resulting
          therefrom; provided that counsel for the Indemnifying Party, who shall
          conduct the defense of such claim or any litigation resulting
          therefrom, shall be approved by the Indemnified Party (whose approval
          shall not unreasonably be withheld) and the Indemnified Party may
          participate in such defense at such party's expense (unless the
          Indemnified


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          Party shall have reasonably concluded that there may be a conflict of
          interest between the Indemnifying Party and the Indemnified Party in
          such action, in which case the fees and expenses of counsel shall be
          at the expense of the Indemnifying Party), and provided further that
          the failure of any Indemnified Party to give notice as provided herein
          shall not relieve the Indemnifying Party of its obligations under this
          Section 2 unless the Indemnifying Party is materially prejudiced
          thereby. No Indemnifying Party, in the defense of any such claim or
          litigation shall, except with the consent of each Indemnified Party,
          consent to entry of any judgment or enter into any settlement which
          does not include as an unconditional term thereof the giving by the
          claimant or plaintiff to such Indemnified Party of a release from all
          liability in respect to such claim or litigation. Each Indemnified
          Party shall furnish such information regarding itself or the claim in
          question as an Indemnifying Party may reasonably request in writing
          and as shall be reasonably required in connection with the defense of
          such claim and litigation resulting therefrom.

               (iv) If the indemnification provided for in this Section 2(f) 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 herein, 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 which resulted in such loss,
          liability, claim, damage or expense, as well as any other relevant
          equitable considerations. 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 (or alleged 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.

               (v) Notwithstanding the foregoing, to the extent that the
          provisions on indemnification and contribution contained in the
          underwriting agreement entered into in connection with any
          underwritten public offering contemplated by this Agreement are in
          conflict with the foregoing provisions, the provisions in such
          underwriting agreement shall be controlling.

               (vi) The foregoing indemnity agreement of the Company and Holders
          is subject to the condition that,


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          insofar as they relate to any loss, claim, liability or damage made in
          a preliminary prospectus but eliminated or remedied in the amended
          prospectus on file with the Commission at the time the registration
          statement in question becomes effective or the amended prospectus
          filed with the Commission pursuant to Commission Rule 424(b) (the
          "Final Prospectus"), such indemnity or contribution agreement shall
          not inure to the benefit of any underwriter or Holder if a copy of the
          Final Prospectus was furnished to the underwriter and was not
          furnished to the person asserting the loss, liability, claim or damage
          at or prior to the time such action is required by the Securities Act.

          (g) INFORMATION BY THE HOLDERS. Each of the Holders holding securities
     included in any registration shall furnish to the Company such information
     regarding such Holder and the distribution proposed by such Holder as the
     Company may reasonably request in writing and as shall be reasonably
     required in connection with any registration, qualification or compliance
     referred to in this Section 2.

          (h) RULE 144 REPORTING.

          With a view to making available the benefits of certain rules and
     regulations of the Commission which may permit the sale of restricted
     securities to the public without registration, the Company agrees to:

               (i) make and keep public information available as those terms are
          understood and defined in Rule 144 under the Securities Act ("Rule
          144"), at all times from and after ninety (90) days following the
          effective date of the first registration under the Securities Act
          filed by the Company for an offering of its securities to the general
          public;

               (ii) use its best efforts to file with the Commission in a timely
          manner all reports and other documents required of the Company under
          the Securities Act and the Exchange Act at any time after it has
          become subject to such reporting requirements; and

               (iii) so long as the Holder owns any Registrable Securities,
          furnish to the Holder upon request, a written statement by the Company
          as to its compliance with the reporting requirements of Rule 144 (at
          any time from and after ninety (90) days following the effective date
          of the first registration statement filed by the Company for an
          offering of its securities to the general public), and of the
          Securities Act and the Exchange Act (at any time after it has become
          subject to such reporting requirements), a copy of the most recent
          annual or quarterly report of the Company, and such other reports and
          documents so filed as the Holder may reasonably request in availing
          itself of any


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          rule or regulation of the Commission allowing the Holder to sell any
          such securities without registration.

          (i) TERMINATION. The registration rights set forth in this Section 2
     shall not be available to any Holder if, in the opinion of counsel to the
     Company, all of the Registrable Securities then owned by such Holder could
     be sold in any 90-day period pursuant to Rule 144 (without giving effect to
     the provisions of Rule 144(k)).

     3. INTERPRETATION OF THIS AGREEMENT

          (a) DIRECTLY OR INDIRECTLY. Where any provision in this Agreement
     refers to action to be taken by any Person, or which such Person is
     prohibited from taking, such provision shall be applicable whether such
     action is taken directly or indirectly by such Person.

          (b) GOVERNING LAW. This Agreement shall be governed by and construed
     in accordance with the laws of the State of New York applicable to
     contracts made and to be performed entirely within such State.

          (c) SECTION HEADINGS. The headings of the sections and subsections of
     this Agreement are inserted for convenience only and shall not be deemed to
     constitute a part thereof.

     4. MISCELLANEOUS

          (a) NOTICES.

               (i) All communications under this Agreement shall be in writing
          and shall be delivered by hand or mailed by overnight courier or by
          registered or certified mail, postage prepaid:

                    (A) if to the Company, to Information Holdings Inc., 250
               Dodge Avenue, East Haven, Connecticut 06512, Attention: Mason P.
               Slaine, or at such other address as it may have furnished in
               writing to the Investors;

                    (B) if to the Investors, at the address listed on Schedule I
               hereto, or at such other address as may have been furnished the
               Company in writing.

               (ii) Any notice so addressed shall be deemed to be given: if
          delivered by hand, on the date of such delivery; if mailed by courier,
          on the first business day following the date of such mailing; and if
          mailed by registered or certified mail, on the third business day
          after the date of such mailing.

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          (b) REPRODUCTION OF DOCUMENTS. This Agreement and all documents
     relating thereto, including, without limitation, any consents, waivers and
     modifications which may hereafter be executed may be reproduced by the
     Investor by any photographic, photostatic, microfilm, microcard, miniature
     photographic or other similar process and the Investors may destroy any
     original document so reproduced. The parties hereto agree and stipulate
     that any such reproduction shall be admissible in evidence as the original
     itself in any judicial or administrative proceeding (whether or not the
     original is in existence and whether or not such reproduction was made by
     the Investors in the regular course of business) and that any enlargement,
     facsimile or further reproduction of such reproduction shall likewise be
     admissible in evidence.

          (c) SUCCESSORS AND ASSIGNS. This Agreement shall inure to the benefit
     of and be binding upon the successors and assigns of each of the parties.

          (d) ENTIRE AGREEMENT; AMENDMENT AND WAIVER. This Agreement constitutes
     the entire understanding of the parties hereto and supersedes all prior
     understanding among such parties. This Agreement may be amended, and the
     observance of any term of this Agreement may be waived, with (and only
     with) the written consent of the Company and the Investors holding a
     majority of the then outstanding Registrable Securities.

          (e) COUNTERPARTS. This Agreement may be executed in one or more
     counterparts, each of which shall be deemed an original and all of which
     together shall be considered one and the same agreement.



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     IN WITNESS WHEREOF, the undersigned have executed this Agreement as of the
date first set forth above.

                                       INFORMATION HOLDINGS INC.


                                       By: /s/ Mason P. Slaine
                                          ----------------------------

                                       INVESTORS:


                                       WARBURG, PINCUS VENTURES, L.P.


                                       By Warburg, Pincus & Co.
                                          Its General Partner


                                       By: /s/ David E. Libowitz
                                          ----------------------------
                                          David E. Libowitz
                                          General Partner



                                       /s/ Mason P. Slaine
                                       ----------------------------
                                       Mason P. Slaine




                                     - 14 -
<PAGE>


                                   SCHEDULE I




Name and Address
OF INVESTOR

Warburg, Pincus Ventures, L.P.
466 Lexington Avenue
New York, New York  10017
Attn:  David E. Libowitz

Mason P. Slaine
c/o Information Holdings Inc.
280 Dodge Avenue
East Haven, Connecticut  06512