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                                                                     Exhibit 2.4

                                                                  EXECUTION COPY

                            TAX ALLOCATION AGREEMENT

         This Tax Allocation Agreement (this "Agreement") is dated as of August
31, 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:
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                                    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 August 31, 2000, by and between IMS and ST.

                  (i) "Distribution Date" shall mean August 31, 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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                  (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.


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                  (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 Schedules 1.1(rrr)(i) and (rrr)(ii) 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.


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                  (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.


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                  (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.


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                  (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


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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 any ST 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 ST Group or any member thereof; and


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                  (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
         3.6, 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 herein).
         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
         3.6, 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


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         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 3.6. 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 IV 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) 841-4115
         Attn: Chief Financial Officer


                                      -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: /s/ MATTHEW L. FRIEDMAN
                                              ---------------------------
                                          Name: Matthew L. Friedman
                                          Title: Vice President


                                          SYNAVANT INC.


                                          By: /s/ JAMES C. MALONE
                                              ---------------------------
                                          Name: James C. Malone
                                          Title: Vice President


                                      -15-