<PAGE>
                                                                    EXHIBIT 10.4

                            TAX ALLOCATION AGREEMENT

      This Tax Allocation Agreement (this "Agreement") is dated as of [______
__], 2000, by and between IMS Health Incorporated, a Delaware corporation
("IMS"), and Synavant Inc., a Delaware corporation ("ST") (each, individually a
"Party," and collectively, the "Parties").

      WHEREAS, IMS acting through its direct and indirect subsidiaries,
currently conducts a number of businesses, including, without limitation,
providing information solutions to the pharmaceutical industry;

      WHEREAS, ST acting through its direct and indirect subsidiaries, currently
conducts a number of businesses, including, without limitation, (i) providing
automated sale support technologies to the pharmaceutical industry, (ii)
providing direct marketing services, and (iii) providing direct mail marketing
services in Australia (all such businesses collectively, the "ST Business");

      WHEREAS, the Board of Directors of IMS has determined that it is
appropriate, desirable and in the best interests of IMS and its businesses as
well as of the holders of shares of common stock, par value $0.01 per share, of
IMS (the "IMS Common Stock"), to reorganize IMS to separate from IMS the ST
Business and to cause such businesses to be owned and conducted, directly or
indirectly, by ST;

      WHEREAS, in order to effect the separation, the Board of Directors of IMS
has determined that it is appropriate, desirable and in the best interests of
IMS and its businesses as well as of the holders of IMS Common Stock, for IMS to
take certain steps to reorganize IMS's Subsidiaries (as defined herein) and
businesses and upon the completion of such reorganization to distribute to the
holders of the IMS Common Stock all the outstanding shares of common stock, par
value $0.01 per share, of ST (the "ST Common Shares");

      WHEREAS, as of the date hereof, IMS is the common parent of an affiliated
group of domestic corporations within the meaning of Section 1504 of the Code
(as defined herein), including members of the ST Group (as defined herein), and
the members of the affiliated group have heretofore joined in filing
consolidated federal Income Tax Returns (as defined herein);

      WHEREAS, as a result of the Distribution, the ST Group will not be
included in the consolidated federal Income Tax Return of IMS for the portion of
the year following the Distribution and in future years; and

      WHEREAS, IMS and ST desire to allocate the Tax (as defined herein) burdens
and benefits of transactions which occurred on or prior to the Distribution Date
(as defined herein) and to provide for certain other Tax matters, including the
assignment of responsibility for the preparation and filing of Tax Returns (as
defined herein), the payment of Taxes, and the prosecution and defense of any
Tax controversies.

      NOW, THEREFORE, in consideration of the mutual agreements, provisions and
covenants contained in this Agreement, the Parties hereby agree as follows:

<PAGE>

                                    ARTICLE I
                                   DEFINITIONS

      SECTION 1.1. GENERAL. Capitalized terms used in this Agreement and not
defined herein shall have the meanings that such terms have in the Distribution
Agreement. As used in this Agreement, the following terms shall have the
following meanings:

            (a) "Code" shall mean the U.S. Internal Revenue Code of 1986, as
amended, and the Treasury regulations promulgated thereunder, including any
successor legislation.

            (b) "Combined Returns" shall mean all state Income Tax Returns with
respect to which IMS files on a combined or unitary basis with some or all of
its Subsidiaries for taxable periods beginning January 1, 1997, January 1, 1998,
January 1, 1999 and January 1, 2000.

            (c) "Consolidated Returns" shall mean all consolidated federal
Income Tax Returns of the affiliated group of which IMS is the common parent for
taxable periods beginning January 1, 1997, January 1, 1998, January 1, 1999 and
January 1, 2000.

            (d) "Controlled Entity" shall mean any corporation, partnership or
other entity of which another entity (i) owns, directly or indirectly, ownership
interests sufficient to elect a majority of the Board of Directors (or persons
performing similar functions) (irrespective of whether at the time any other
class or classes of ownership interests of such corporation, partnership or
other entity shall or might have such voting power upon the occurrence of any
contingency) or (ii) is a general partner or an entity performing similar
functions (e.g., a trustee).

            (e) "D&B Tax Allocation Agreement" shall mean the Tax Allocation
Agreement dated as of October 28, 1996 among The Dun & Bradstreet Corporation,
IMS and ACNielsen Corporation.

            (f) "IMS Tax Allocation Agreement" shall mean the Tax Allocation
Agreement dated as of June 30, 1998 between Cognizant Corporation and IMS Health
Incorporated.

            (g) "Distribution" shall mean the distribution on the Distribution
Date to holders of record of shares of IMS Common Stock as of the Distribution
Record Date of the ST Common Shares owned by IMS on the basis of one ST Common
Share for every 20 shares of IMS Common Stock.

            (h) "Distribution Agreement" shall mean the Distribution Agreement,
dated as of [____ __], 2000, by and between IMS and ST.

            (i) "Distribution Date" shall mean [____ __], 2000.

            (j) "Final Determination" shall mean the final resolution of
liability for any Tax for any taxable period, including any related interest or
penalties, by or as a result of: a final and unappealable decision, judgment,
decree or other order by any court of competent jurisdiction; (ii) a closing
agreement or accepted offer in compromise under Section 7121 or 7122 of the
Code, or comparable agreement under the laws of other jurisdictions which
resolves the entire Tax liability for any taxable period; (iii) any allowance of
a refund or credit in respect of an overpayment of Tax, but only after the
expiration of all periods during which such refund may be recovered by the
jurisdiction imposing the Tax; or (iv) any other final disposition, including by
reason of the expiration of the applicable statute of limitations.


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<PAGE>

            (k) "Foreign Tax Agreement" shall have the meaning as defined in
Section 6.2

            (l) "Franchise Tax Returns" shall mean all franchise Tax Returns of
the Pre-Distribution IMS Group or any member thereof for taxable periods
beginning January 1, 1997, January 1, 1998, January 1, 1999 and January 1, 2000.

            (m) "Governmental Authority" shall mean any federal, state, local,
foreign or international court, government, department, commission, board,
bureau, agency, official or other regulatory, administrative or governmental
authority.

            (n) "Included Party" shall have the meaning as defined in Section
2.3.

            (o) "Income Tax Return" shall mean any Tax Return relating to Income
Taxes.

            (p) "Income Taxes" shall mean any federal, state or local Taxes
determined by reference to income or imposed in lieu of income Taxes, such as
Taxes based on net worth or gross receipts.

            (q) "Indemnifying Party" shall have the meaning as defined in
Section 3.5.

            (r) "Indemnitee" shall have the meaning as defined in Section 3.5.

            (s) "IRS" shall mean the U.S. Internal Revenue Service.

            (t) "IMS" shall have the meaning set forth in the recitals hereto.

            (u) "IMS Assets" shall have the same meaning as such term has in the
Distribution Agreement.

            (v) "IMS Business" shall mean each and every business conducted at
any time by IMS or any subsidiary of IMS prior to the Effective Time, including,
without limitation, providing information solutions services to the
pharmaceutical and healthcare industries, the business of the members of the IMS
Group, any other business conducted by IMS or any Subsidiary of IMS primarily
through the use of IMS Assets, the businesses of any Business Entity acquired or
established by or for IMS or any of its Subsidiaries after the date of this
Agreement, and the business of IMS from and after the Effective Time, but
excluding the ST Business.

            (w) "IMS Group" shall mean IMS, each Business Entity which is
contemplated to remain or become a Subsidiary of IMS hereunder, which shall
include those identified as such on Schedule [1.1(au)] to the Distribution
Agreement, from and after the Effective Time.

            (x) "Non-Combined Returns" shall mean all state and local Income Tax
Returns (other than Combined Returns and any foreign Tax Returns), of the
Pre-Distribution IMS Group or any member thereof for taxable periods beginning
January 1, 1997, January 1, 1998, January 1, 1999 and January 1, 2000.

            (y) "Nonperforming Party" shall have the meaning as defined in
Section 5.2.

            (z) "Old IMS Group" shall mean IMS and all of its Subsidiaries
(direct and indirect, domestic and foreign) prior to Distribution.


                                      -3-
<PAGE>

            (aa) "Other Taxes" shall mean all Taxes other than Taxes covered by
a Consolidated Return, a Combined Return, a Non- Combined Return or a Franchise
Tax Return.

            (ab) "Party" or "Parties" shall have the meanings as defined in the
recitals hereto.

            (ac) "Person" shall mean any natural person, corporation, business
trust, joint venture, association, company, partnership or government, or any
agency or political subdivision thereof.

            (ad) "Pre-Distribution IMS Group" shall mean IMS and all of its
Subsidiaries (direct and indirect, domestic and foreign) prior to the
Distribution.

            (ae) "Preparing Party" shall have the meaning as defined in Section
2.3.

            (af) "Reorganization Tax Payment" shall mean the payment of any Tax
for which IMS is liable pursuant to Section 3.3 of this Agreement.

            (ag) "Reorganizations" shall mean the series of contributions and
distributions of Controlled Entities and assets, transfers and assumptions of
liabilities, and other transactions whereby the IMS Group and the ST Group are
formed and all other Controlled Entities of IMS prior to the Distribution are
placed under the control of the appropriate parent corporation(s) in preparation
for the Distribution.

            (ah) "ST Business" shall have the meaning set forth in the recitals
hereto.

            (ai) "ST Group" shall mean ST and each business entity which is
contemplated to remain or become a subsidiary of ST hereunder, which shall
include those identified on Schedule [__] to the Distribution Agreement. (other
than any member of the IMS Group) that is a Subsidiary of ST immediately prior
to the Effective Time, including, without limitation, Clark-O'Neill, Inc., a New
Jersey corporation, which will be merged with and into ST prior to the Effective
Time.

            (aj) "Subsidiary" shall mean any entity of which another entity's
ownership satisfies the 80-percent voting and value test defined in Section
1504(2) of the Code, whether directly or indirectly.

            (ak) "Tax" or "Taxes" whether used in the form of a noun or
adjective, shall mean taxes on or measured by income, franchise, gross receipts,
sales, use, excise, payroll, personal property, real property, ad-valorem,
value-added, leasing, leasing use or other taxes, levies, imposts, duties,
charges or withholdings of any nature. Whenever the term "Tax" or "Taxes" is
used (including, without limitation, regarding any duty to reimburse another
Party for indemnified taxes or refunds or credits of taxes) it shall include
penalties, fines, additions to tax and interest thereon.

            (al) "Tax Item" shall mean any item of income, capital gain, net
operating loss, capital loss, deduction, credit or other Tax attribute relevant
to the calculation of a Tax liability.

            (am) "Tax Matters Partner" shall mean the tax matters partner as
defined in Section 6231(a)(7) of the Code.


                                      -4-
<PAGE>

            (an) "Tax Returns" shall mean all reports or returns (including
information returns) required to be filed or that may be filed for any period
with any taxing authority (whether domestic or foreign) in connection with any
Tax or Taxes (whether domestic or foreign).

      SECTION 1.2. REFERENCES; INTERPRETATION. References in this Agreement to
any gender include references to all genders, and references to the singular
include references to the plural and vice versa. The words "include", "includes"
and "including" when used in this Agreement shall be deemed to be followed by
the phrase "without limitation". Unless the context otherwise requires,
references in this Agreement to Articles, Sections, Exhibits and Schedules shall
be deemed references to Articles and Sections of, and Exhibits and Schedules to,
such Agreement. Unless the context otherwise requires, the words "hereof",
"hereby" and "herein" and words of similar meaning when used in this Agreement
refer to this Agreement in its entirety and not to any particular Article,
Section or provision of this Agreement.

                                   ARTICLE II
                      PREPARATION AND FILING OF TAX RETURNS

      SECTION 2.1. PREDISTRIBUTION TAX RETURNS. (a) IMS shall prepare, and IMS
shall file, (i) all Consolidated Returns, Combined Returns, Non-Combined
Returns, and Franchise Tax Returns that are not filed prior to the Distribution
Date and (ii) any Tax Returns of any partnership of which IMS or any Subsidiary
is the Tax Matters Partner if a distributive share of partnership income or loss
is included in any such Return.

            (b) All Tax Returns for Other Taxes for periods beginning prior to
the Distribution Date that are not subject to the D&B Tax Allocation Agreement
and the IMS Tax Allocation Agreement shall be prepared and filed by ST if they
relate to any ST Business, and otherwise, by IMS.

            (c) All foreign Tax Returns that are required to be filed by or
relating to any member of the Old IMS Group for periods beginning before the
Distribution Date shall be prepared and filed by the entity that filed the
corresponding Tax Return for the most recent period for which such a Tax Return
has been filed, or, if no such corresponding Tax Return has been filed, by the
appropriate entity in accordance with local law or custom.

      SECTION 2.2. POST-DISTRIBUTION TAX RETURNS. (a) The filing of all Tax
Returns for periods beginning on or after the Distribution Date shall be the
responsibility of IMS if they relate to the IMS Group or any member thereof and
shall be the responsibility of ST if they relate to the ST Group or any member
thereof.

            (b) In the case of any partnership in which a member of the
Pre-Distribution IMS Group is the designated Tax Matters Partner, such entity
shall continue to be responsible for the preparation and filing of such
partnership's Tax Returns.

      SECTION 2.3. MANNER OF PREPARATION. (a) To the extent any Tax Return
includes Taxes relating to a Party (or any of its Subsidiaries) other than the
Party preparing such Tax Return (the "Preparing Party"), the Party not
responsible for preparing the Tax Return (the "Included Party"), shall prepare
and deliver to the Preparing Party, at least 60 days prior to the due date
(including extensions) of such Tax Return, a true and correct accounting of all
relevant Tax Items relating to the Included Party (and any of its Subsidiaries)
for the taxable period.


                                      -5-
<PAGE>

            (b) All Tax Returns filed on or after the Distribution Date shall be
prepared on a basis that is consistent with the tax opinion obtained from
McDermott, Will & Emery in connection with the Reorganizations or Distribution
(in the absence of a controlling change in law or circumstances) and shall be
filed on a timely basis (including pursuant to extensions) by the Party
responsible for such filing under this Agreement. In the absence of a
controlling change in law or circumstances and unless deviation from past
practice would have no adverse effect on the other Party, all Tax Returns filed
within three years after the Distribution Date shall be prepared on a basis
consistent with the elections, accounting methods, conventions, assumptions and
principles of taxation used for the most recent taxable periods for which Tax
Returns involving similar Tax Items have been filed; provided, however, that a
Party preparing any Tax Return that does not conform to such past practices
shall not be liable for any additional Tax liability imposed, in whole or in
part, as a result of such deviation from past practice if: (i) 30 days prior to
the filing of such Tax Return, the Party preparing such Tax Return notifies the
other Party if such other Party may be adversely affected; and (ii) the Party
preparing such Tax Return establishes that conformity with past practice
involves a significant risk of the imposition of a penalty. Subject to the
provisions of this Agreement, all decisions relating to the preparation of Tax
Returns shall be made in the sole discretion of the Party responsible under this
Agreement for its preparation; provided, however, that the "Included Party"
shall have the right to review and comment on such Tax Return prior to the
filing thereof in the following manner:

      The Preparing Party shall submit any part of such Tax Return relating to
the Included Party (or any of its Subsidiaries) to the Included Party at least
14 days prior to the date on which such Tax Return is due (including
extensions). The Included Party shall submit its comments to the Preparing Party
within 7 days of receipt of the relevant portions of such Tax Return. The
Preparing Party shall alter such Tax Return to reflect the reasonable comments
of the Included Party unless the Preparing Party reasonably believes that such
alteration would have an adverse impact upon the Preparing Party.

            (c) Unless otherwise required by the IRS, any Governmental Authority
or a court, the Parties hereby agree to file all Tax Returns, and to take all
other actions, in a manner consistent with the position that the Distribution
Date is the last day on which any member of the ST Group was included in the
Pre-Distribution IMS Group. For any period that includes but does not end on the
Distribution Date, to the extent permitted by law or administrative practice,
the taxable year of each ST Group member of the Pre-Distribution IMS Group and
any group of such members shall be treated as ending on the Distribution Date.





                                  ARTICLE III
                                PAYMENT OF TAXES

      SECTION 3.1. PREDISTRIBUTION TAXES. (a) The Party responsible for the
filing of any Tax Return pursuant to Sections 2.1 and 2.2 shall pay to the
relevant taxing authority all Taxes due or payable in connection therewith;
provided, that if, pursuant to this Article III, one Party is liable for any
Taxes relating to a Tax Return filed by the other Party, such non-filing Party
shall pay the filing Party the amount of such Taxes at least 5 days prior to the
due date (including extensions) of such Tax Return.


                                      -6-
<PAGE>

            (b) With respect to any Consolidated Return, Combined Return,
Non-Combined Return or Franchise Tax Return for a taxable period ending before
January 1, 2000 that is not filed prior to the Distribution Date, IMS shall be
liable for all Taxes payable with such Return and shall be entitled to any
refund or credit for an overpayment of Taxes shown on such Return. With respect
to any Consolidated Return, Combined Return, Non-Combined Return or Franchise
Tax Return for a taxable period beginning on or after January 1, 2000, IMS shall
only be liable for Taxes payable with such Return that are attributable to the
portion of such taxable period up to and including the Distribution Date and
that exceed the amount of Taxes paid in respect of such taxable period (as
estimated Taxes or otherwise) on or prior to the Distribution Date and (ii)
shall be entitled to any refund or credit of Taxes to the extent Taxes paid in
respect of such taxable period (as estimated Taxes or otherwise) on or prior to
the Distribution Date exceed the amount of Taxes attributable to the portion of
the period up to and including the Distribution Date. The determination of the
amount of Taxes attributable to the portion of such taxable period up to and
including the Distribution Date shall be done on the basis of the books of IMS,
except that Tax Items calculated on an annual basis shall be apportioned on a
time basis.

            (c) In the event of any Final Determination adjusting the amount of
any Taxes that are the subject of a Consolidated Return, Combined Return,
Non-Combined Return or Franchise Tax Return, ST shall be liable for its share of
any increases in Taxes and shall be entitled to its share of any refunds or
credits of Taxes, and IMS shall be liable for all other increases in Taxes and
shall be entitled to all other refunds or credits of Taxes, all in accordance
with the principles of Sections 3.1(a) and (b) above.

            (d) IMS shall be liable for all Other Taxes that are attributable to
the IMS Business and ST shall be liable for all Other Taxes that are
attributable to the ST Business.

            (e) In the case of any Consolidated Return, Combined Return,
Non-Combined Return or Franchise Tax Return with respect to which IMS has
responsibility for any Taxes or is entitled to any refunds or credits of Taxes
pursuant to this Section 3.1, IMS shall have the right to prepare an amended Tax
Return. ST shall have the right to review any such amended Tax Return and shall
be required to sign and file any such amended Tax Return unless it reasonably
determines that the filing of such amended Tax Return would create a substantial
risk of a material increase in the Taxes payable by the ST Group or any member
thereof for any taxable period beginning on or after the Distribution Date. IMS
shall be entitled to any refunds or credits of Taxes relating to any such
amended Tax Return.

            (f) If IMS is liable for any Taxes or entitled to any refunds or
credits of Taxes pursuant to the D&B Tax Allocation Agreement or the IMS Tax
Allocation Agreement, such Taxes, refunds or credits shall be allocated between
IMS and ST in accordance with the principles of this Section 3.1.

            (g) Notwithstanding any statement herein to the contrary, any Taxes
covered by Section [2.1(j)] of the Distribution Agreement shall be governed by
Schedule [2.1(j)(i)] to the Distribution Agreement.

            (h) The entity responsible for the filing of any foreign Tax Return
pursuant to Section 2.1 (c) shall pay to the relevant taxing authority all Taxes
due or payable (or receive all refunds) in connection therewith; PROVIDED,
HOWEVER, that each of the Parties shall be liable for all foreign Taxes (or be
entitled to receive all refunds) for all taxable periods beginning prior to the
Distribution Date, including audit adjustments thereto, relating to such Party's
businesses. To the extent any foreign Tax Return includes Taxes relating to a
business other than the Preparing


                                      -7-
<PAGE>

Party's business, the Included Party shall prepare and deliver to the Preparing
Party, at least 90 days prior to the due date (including extensions) of such
foreign Tax Return, a true and correct accounting of all relevant Tax Items and
corresponding Taxes relating to the Included Party's business for the taxable
period ("Separate Business Foreign Taxes") and shall pay the Preparing Party the
amount of any such Separate Business Foreign Taxes at that time. Separate
Business Foreign Taxes shall be calculated as if the Included Party's business
were a separate taxpayer for the relevant taxable period. All such calculations
shall be based upon the business's actual Tax attributes for the relevant
taxable period, including the use of the business's Tax attributes (such as
losses or credits) from prior periods that are not otherwise utilized and that
are carried over to the relevant taxable period under local law. Tax items that
relate to or arise out of the Tax planning of the group of entities or
businesses included in the relevant foreign Tax Return as a whole rather than
any separate entity or business shall not be included in the calculation of
Separate Business Foreign Taxes.

                  (i)   If the total liability for Taxes reported as due and
      payable on the relevant foreign Tax Return exceeds or is less than the
      total of the Separate Business Foreign Taxes for all businesses included
      in such foreign Tax Return, then the cost or benefit of any net difference
      shall be allocated to each business in proportion to the amount of taxable
      income generated by such business.

                  (ii)  Notwithstanding any statement to the contrary in this
      Section 3.1(h), the Separate Business Foreign Taxes of any entity shall
      not exceed the total liability for Taxes reported as due and payable on
      the relevant foreign Tax Return.

                  (iii) In the event of any Final Determination upholding an
      audit adjustment to the amount of foreign Taxes reported as due and
      payable on the relevant foreign Tax Return, Separate Business Foreign
      Taxes shall be recalculated to incorporate any such adjustment.

      SECTION 3.2. POST-DISTRIBUTION TAXES.  Unless otherwise provided in this
Agreement:

            (a) IMS shall pay all Taxes and shall be entitled to receive and
retain all refunds of Taxes:

                  (i)   with respect to a Consolidated Return, Combined
      Return, Non-Combined Return or Franchise Tax Return for a taxable period
      that begins prior to the Distribution Date and includes but does not end
      on the Distribution Date to the extent such Taxes or refunds are
      attributable to (y) the portion of such period after the Distribution Date
      and (z) the IMS Group or any member thereof; and

                  (ii)  with respect to periods beginning on or after the
      Distribution Date that are attributable to the IMS Group or any member
      thereof.

            (b) ST shall pay all Taxes and shall be entitled to receive and
retain all refunds of Taxes:

                  (i)   with respect to a taxable period that begins prior to
      the Distribution Date, and includes but does not end on the Distribution
      Date, to the extent such Taxes or refunds are attributable to (y) the
      portion of such period after the Distribution Date and (z) the ST Group or
      any member thereof; and


                                      -8-
<PAGE>

                  (ii)  with respect to periods beginning on or after the
      Distribution Date that are attributable to the ST Group or any member
      thereof.

      SECTION 3.3. REORGANIZATION TAXES. (a) Notwithstanding any statement to
the contrary in this Agreement and except as otherwise provided in the
Distribution Agreement, to the extent that any Taxes are found to arise out of
the Reorganizations, then any such Tax liability incurred by the Parties (or any
of their Subsidiaries) shall be the responsibility of IMS.

            (b) Notwithstanding any statement herein to the contrary, any Taxes
relating to or arising out of the Distribution shall be governed by Section
[2.11] of the Distribution Agreement.

      SECTION 3.4. GAIN RECOGNITION AGREEMENTS. In the event that the ST Group
transfers, liquidates or otherwise disposes of the stock or assets of any entity
listed on Schedule 3.4 and such transfer, liquidation or disposition results in
IMS recognizing gain pursuant to a gain recognition agreement under Section
367(a) of the Code, then ST shall be liable for any resulting Taxes, including
interest, that IMS is required to pay.

      SECTION 3.5. SUBPART F INCLUSIONS.

            (a) If income earned by any foreign member of the ST Group is
required to be included in the United States federal income tax return of any
member of the ST Group pursuant to Subpart F of the Code ("Subpart F Income"),
then IMS shall be liable for the Taxes attributable to the portion of such
income generated while such foreign member of the ST Group was a member of the
Old IMS Group. The portion of such income which shall be considered attributable
to the period in which such foreign member was a member of the Old IMS Group
shall be computed as if the foreign member's taxable year ended on July 31,
2000.

            (b) The amount payable by IMS pursuant to this Section 3.5 shall not
exceed the actual Taxes payable with respect to such Subpart F Income minus any
foreign Tax credits attributable to such Subpart F Income.

      SECTION 3.6. INDEMNIFICATION.

            (a) Indemnification by IMS. IMS shall indemnify, defend and hold
harmless ST (and its affiliates) from and against any and all Tax liabilities
allocated to IMS by this Agreement.

            (b) Indemnification by ST. ST shall indemnify, defend and hold
harmless IMS (and its affiliates) from and against any and all Tax liabilities
allocated to ST by this Agreement.

            (c) Indemnity Payments.

                  (i)   To the extent that one Party (the "Indemnifying Party")
      owes money to another Party (the "Indemnitee") pursuant to this Section
      3.5, the Party (the "Notifying Party") having knowledge of such obligation
      shall notify the other Party and shall provide such other Party with its
      calculations of such obligation (as specified in I and Article III). The
      other Party, within 14 days after receiving the Notifying Party's
      calculations, shall submit to the Notifying Party such other Party's
      calculations of the amount required to be paid pursuant to this Section
      3.5, showing such calculations in sufficient detail so as to permit the
      Notifying Party to understand the calculations. The Indemnifying Party
      shall pay the Indemnitee, no later than the later of 5 days prior to the


                                      -9-
<PAGE>

      due date (including extensions) of the relevant Tax Returns and 14 days
      after the Notifying Party receives the other Party's calculations, the
      amount for which the Indemnifying Party is required to pay or indemnify
      the Indemnitee under this Section 3.5. The Indemnifying Party shall have
      the right to disagree with the Indemnitee's calculations. Any dispute
      regarding such calculations shall be resolved in accordance with Section
      5.4 of this Agreement.

                  (ii)  All indemnity payments shall be calculated on a pre-Tax
      basis and shall be treated as contributions to capital and/or dividends
      immediately prior to the Distribution.


                                   ARTICLE IV
                 TAX ATTRIBUTES AND REORGANIZATION TAX PAYMENTS

      SECTION 4.1. CARRYBACKS. In the event of the realization of any deduction,
loss or credit by a Party for any taxable period beginning on or after the
Distribution Date, the Party realizing such deduction, loss or credit may, in
its sole discretion, and to the extent permitted under applicable Tax law, elect
to either carry back or carry forward such deduction, loss or credit. Any refund
attributable to such carryback shall be allocable to such Party. In the event
both Parties elect to carry back an amount to the same taxable period beginning
prior to the Distribution Date, any refund shall be apportioned between the
Parties based on the relative carryback amounts.

      SECTION 4.2. COMPETENT AUTHORITY RELIEF. If as a result of any audit of a
taxable period beginning prior to the Distribution Date, a Party (or Subsidiary)
is required to adjust its income, deductions, credits or allowances under
Section 482 of the Code or under similar principles in a foreign jurisdiction,
and the payment of additional Taxes in accordance with such a determination
allows the other Party (or Subsidiary) to obtain competent authority relief as a
result thereof, then the Party eligible to obtain such relief shall (a) execute
or cause to be executed any powers of attorney or other documents necessary to
enable the other Party to pursue such relief at its own expense; and (b)
cooperate with the other Party and the competent authorities in seeking such
relief.


                                   ARTICLE V
                   TAX AUDITS, TRANSACTIONS AND OTHER MATTERS

      SECTION 5.1. TAX AUDITS AND CONTROVERSIES. In the case of any audit,
examination or other proceeding ("Proceeding") brought against a Party (or
Subsidiary) with respect to Taxes for which the other Party is or may be liable
pursuant to this Agreement, the Party subject to such Proceeding shall promptly
inform such other Party and shall execute or cause to be executed any powers of
attorney or other documents necessary to enable the other Party to take all
actions desired with respect to such Proceeding to the extent such Proceeding
may affect the amount of Taxes for which the other Party is liable pursuant to
this Agreement. Each Party shall have the right to control, at its own expense,
the portion of any such Proceeding that relates to Taxes for which such Party is
or may be liable pursuant to this Agreement; provided, however, that such Party
shall consult with the other Party with respect to any issue that may affect the
other Party (or Subsidiary). The Party in control of such Proceeding or any part
thereof shall not enter into any final settlement or closing agreement that may
adversely affect the other Party (or Subsidiary) without the consent of such
other Party, which consent may not unreasonably be withheld. Where consent to
any final settlement or closing agreement is withheld, the Party withholding
consent


                                      -10-
<PAGE>

shall continue or initiate further proceedings, at its own expense, and the
liability of the Party in control of such Proceeding shall not exceed the
liability that would have resulted from the proposed closing agreement or final
settlement (including interest, additions to Tax and penalties which have
accrued at that time).

      SECTION 5.2. COOPERATION. IMS and ST shall cooperate with each other in
the filing of any Tax Returns and the conduct of any audit or other proceeding
and each shall execute and deliver such powers of attorney and other documents
and make available such information, personnel and documents as are necessary to
carry out the intent of this Agreement. To the extent such cooperation involves
the services of officers, directors, employees, or agents of a Party, such
services shall be made available in accordance with Section 2.9 of the
Distribution Agreement. Each Party agrees to notify the other Party of any audit
adjustment that does not result in Tax liability but can reasonably be expected
to affect Tax Returns of the other Party or any of its Subsidiaries.
Notwithstanding any other provision of this Agreement, if a Party (the
"Nonperforming Party") fails to give its full cooperation and use its best
efforts in the conduct of an audit or other proceeding as provided by this
Section 5.2, and such failure results in the imposition of additional Taxes for
the period or periods involved in the audit or other proceeding, the
Nonperforming Party shall be liable in full for such additional Taxes.

      SECTION 5.3. RETENTION OF RECORDS; ACCESS. Beginning on the Distribution
Date, IMS and ST shall, and shall cause each of their Controlled Entities to:

            (a) retain adequate records, documents, accounting data and other
information (including computer data) necessary for the preparation and filing
of all Tax Returns required to be filed by any member of the Pre-Distribution
IMS Group or any combination of such members and for any audits and litigation
relating to such Tax Returns or to any Taxes payable by any member of the
Pre-Distribution IMS Group or any combination of such members; and

            (b) give to the other Party reasonable access to such records,
documents, accounting data and other information (including computer data) and
to its personnel and premises, for the purpose of the review or audit of such
reports or returns to the extent relevant to an obligation or liability of a
Party under this Agreement and in accordance with the procedures provided in
Article [__] of the Distribution Agreement. The obligations set forth in these
paragraphs 5.3(a) and 5.3(b) shall continue until the final conclusion of any
litigation to which the records and information relate or until expiration of
all applicable statutes of limitations, whichever is longer.

      SECTION 5.4. DISPUTE RESOLUTION. Any dispute or claim arising out of, in
connection with, or in relation to the interpretation, performance,
nonperformance, validity or breach of this Agreement or otherwise arising out
of, or in any way related to this Agreement, shall be resolved in the manner set
forth in Article VI of the Distribution Agreement.

      SECTION 5.5. CONFIDENTIALITY; OWNERSHIP OF INFORMATION; PRIVILEGED
INFORMATION. The provisions of Article IV of the Distribution Agreement relating
to confidentiality of information, ownership of information, privileged
information and related matters shall apply with equal force to any records and
information prepared and/or shared by and between the Parties in carrying out
the intent of this Agreement.

                                   ARTICLE VI
                                  MISCELLANEOUS


                                      -11-
<PAGE>

      SECTION 6.1. COMPLETE AGREEMENT; CONSTRUCTION. This Agreement, including
the Exhibits and Schedules, shall constitute the entire agreement between the
Parties with respect to the subject matter hereof and shall supersede all
previous negotiations, commitments and writings with respect to such subject
matter. In the event of any inconsistency between this Agreement and any
Schedule hereto, the Schedule shall prevail.

      SECTION 6.2. MASTER TAX ALLOCATION AGREEMENT. This Agreement, including
the Exhibits and Schedules, shall take precedence over any and all agreements
with respect to foreign Taxes among members of the IMS Group and the ST Group (a
"Foreign Tax Agreement"). In the event that any payment is made or other action
taken by a member of the IMS Group or the ST Group pursuant to any Foreign Tax
Agreement and contrary to the terms of this Agreement, then an offsetting
indemnity payment shall be made by the appropriate Party to the injured Party to
conform with the provisions of this Agreement.

      SECTION 6.3. COUNTERPARTS. This Agreement may be executed in one or more
counterparts, all of which shall be considered one and the same agreement, and
shall become effective when one or more such counterparts have been signed by
each of the Parties and delivered to the other Party.

      SECTION 6.4. SURVIVAL OF AGREEMENTS. Except as otherwise provided by this
Agreement, all covenants and agreements of the Parties contained in this
Agreement shall survive the Distribution Date.

      SECTION 6.5. EXPENSES. Except as otherwise set forth in this Agreement,
all costs and expenses in connection with the preparation, execution, delivery
and required implementation of this Agreement shall be charged to and paid by
the Parties in accordance with Section [8.5] of the Distribution Agreement.

      SECTION 6.6. NOTICES. All notices and other communications hereunder shall
be in writing and hand delivered or mailed by registered or certified mail
(return receipt requested) or sent by any means of electronic message
transmission with delivery confirmed (by voice or otherwise) to the Parties at
the following addresses (or at such other addresses for a Party as shall be
specified by like notice) and will be deemed given on the date on which such
notice is received:

      To IMS:

      200 Nyala Farms
      Westport, CT 06880
      Telecopy: (203) 222-4313
      Attn: General Counsel
            and Vice President - Taxes

      To ST:

      3445 Peachtree Rd., NE, Suite 1400
      Atlanta, GA  30326
      Telecopy:  (404) 841-[_____]
      Attn: General Counsel


                                      -12-
<PAGE>

      SECTION 6.7. WAIVERS. The failure of any Party to require strict
performance by any other Party of any provision in this Agreement will not waive
or diminish that Party's right to demand strict performance thereafter of that
or any other provision hereof.

      SECTION 6.8. AMENDMENTS. This Agreement may not be modified or amended
except by an agreement in writing signed by each of the Parties hereto.

      SECTION 6.9. ASSIGNMENT. This Agreement shall not be assignable, in whole
or in part, directly or indirectly, by any Party hereto without the prior
written consent of the other Party hereto, and any attempt to assign any rights
or obligations arising under this Agreement without such consent shall be void.

      SECTION 6.10. SUCCESSORS AND ASSIGNS. The provisions to this Agreement
shall be binding upon, inure to the benefit of and be enforceable by the Parties
and their respective successors and permitted assigns.

      SECTION 6.11. TERMINATION. This Agreement may be terminated, amended,
modified or abandoned at any time prior to the Distribution by and in the sole
discretion of IMS without the approval of ST or the stockholders of IMS. In the
event of such termination, neither Party shall have any liability of any kind to
the Party or any other person. After the Distribution, this Agreement may not be
terminated except by an agreement in writing signed by the Parties.

      SECTION 6.12. CONTROLLED ENTITIES. Each of the Parties hereto shall cause
to be performed, and hereby guarantees the performance of, all actions,
agreements and obligations set forth herein to be performed by any Controlled
Entity of such Party or by any entity that is contemplated to be a Controlled
Entity of such Party on and after the Distribution Date.

      SECTION 6.13. THIRD PARTY BENEFICIARIES. This Agreement is solely for the
benefit of the Parties hereto and their respective Subsidiaries and should not
be deemed to confer upon third parties any remedy, claim, liability,
reimbursement, claim of action or other right in excess of those existing
without reference to this Agreement.

      SECTION 6.14. TITLE AND HEADINGS. Titles and headings to sections herein
are inserted for the convenience of reference only and are not intended to be a
part of or to affect the meaning or interpretation of this Agreement.

      SECTION 6.15. EXHIBITS AND SCHEDULES. The Exhibits and Schedules shall be
construed with and as an integral part of this Agreement to the same extent as
if the same had been set forth verbatim herein.

      SECTION 6.16. 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 IN THE STATE OF NEW YORK.

      SECTION 6.17. CONSENT TO JURISDICTION. Without limiting the provisions of
Section 5.4 hereof, each of the Parties irrevocably submits to the exclusive
jurisdiction of the Supreme Court of the State of New York, New York County, and
(b) the United States District Court for the Southern District of New York, for
the purposes of any suit, action or other proceeding arising out of this
Agreement or any transaction contemplated hereby. Each of the Parties agrees to
commence any action, suit or proceeding relating hereto either in the United
States District Court


                                      -13-
<PAGE>

for the Southern District of New York or if such suit, action or other
proceeding may not be brought in such court for jurisdictional reasons, in the
Supreme Court of the State of New York, New York County. Each of the Parties
further agrees that service of any process, summons, notice or document by U.S.
registered mail to such Party's respective address set forth above shall be
effective service of process for any action, suit or proceeding in New York with
respect to any matters to which it has submitted to jurisdiction in this Section
6.17. Each of the Parties irrevocably and unconditionally waives any objection
to the laying of venue of any action, suit or proceeding arising out of this
Agreement or the transactions contemplated hereby in the Supreme Court of the
State of New York, New York County, or (ii) the United States District Court for
the Southern District of New York, and hereby further irrevocably and
unconditionally waives and agrees not to plead or claim in any such court that
any such action, suit or proceeding brought in any such court has been brought
in an inconvenient forum.

      SECTION 6.18. SEVERABILITY. In the event any one or more of the provisions
contained in this Agreement should be held invalid, illegal or unenforceable in
any respect, the validity, legality and enforceability of the remaining
provisions contained herein and therein shall not in any way be affected or
impaired thereby. The Parties shall endeavor in good-faith negotiations to
replace the invalid, illegal or unenforceable provisions with valid provisions,
the economic effect of which comes as close as possible to that of the invalid,
illegal or unenforceable provisions.



                                      -14-
<PAGE>

      IN WITNESS WHEREOF, the Parties have caused this Agreement to be duly
executed as of the day and year first above written.

                                    IMS HEALTH INCORPORATED


                                       By:_________________________
                                       Name:
                                       Title:


                                    SYNAVANT INC.


                                       By:_________________________
                                       Name:
                                       Title:




                                      -15-