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                                                                   EXHIBIT 10.29



                               INDEMNITY AGREEMENT

      THIS INDEMNITY AGREEMENT (the "Agreement"), made and entered into this 8th
day of March, 2002, by and between ASCENTIAL SOFTWARE CORPORATION, a Delaware
corporation (the "Company"), and the undersigned (the "Indemnitee").

                                   WITNESSETH:

      WHEREAS, competent and experienced persons are increasingly reluctant to
serve as directors, officers, employees and agents of corporations because of
increased exposure to litigation costs and risks and because the exposure
frequently bears no reasonable relationship to their compensation;

      WHEREAS, litigation against an officer, director, employee or agent often
involves the knowledge, motive and intent of the officer, director, employee or
agent and the long period of time vents giving rise to the litigation and its
final disposition often extends beyond the time the officer, director, employee
or agent can reasonably recall such matters, the retirement of the officer,
director, employee or agent or the death of the officer, director, employee or
agent with the result that he or, in the event of his death, his heirs,
executors or administrators, may be faced with limited ability and undue
hardship in maintaining an adequate defense, which may discourage such a
director, officer, employee or agent from serving in that position;

      WHEREAS, the Board of Directors of the Company has concluded that, to
retain and attract talented and experienced individuals to serve as officers,
directors, employees and agents of the Company and its subsidiaries and to
encourage such individuals to take the business risks necessary for the success
of the Company and its subsidiaries, it is necessary for the Company to
contractually indemnify the officers, directors, employees and agents of the
Company and of its subsidiaries, and to assume for itself maximum liability for
expenses and damages in connection with claims against such officers, directors,
employees and agents in connection with their service to the Company and its
subsidiaries;

      WHEREAS, Section 145 of the General Corporation Law of Delaware ("Section
145") empowers the Company to indemnify its officers, directors, employees and
agents by agreement and to indemnify persons who serve, at the request of the
Company, as the directors, officers, employees or agents of other corporations
or enterprises;

      WHEREAS, the stockholders of the Company have adopted or will adopt
by-laws (the "By-laws") providing for the indemnification of the officers,
directors, employees and agents of the Company;

      WHEREAS, such By-laws and Section 145 specifically provide that they are
not exclusive and contemplate that contracts may be entered into between the
Company and the directors, officers, employees and agents with respect to
indemnification of such directors, officers, employees and agents;

      WHEREAS, the Company desires and has requested the Indemnitee to serve or
continue to serve as a director and/or officer and/or employee and/or agent of
the Company and/or one or more subsidiaries of the Company; and

      WHEREAS, the Indemnitee is willing to serve, or to continue to serve, the
Company and/or one or more subsidiaries of the Company as a director and/or
officer and/or employee and/or agent, provided that he is furnished the
indemnity provided for herein.

      NOW, THEREFORE, for and in consideration of the foregoing and the mutual
promises contained herein, the parties hereto hereby agree as follows:


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1. Definitions. When used herein.

                  (a) "Agent" shall mean any person who is or was a director,
            officer, employee or other agent of the Company or a Subsidiary, as
            hereinafter defined: or is or was serving in a fiduciary capacity
            within the meaning of the Employee Retirement Income Security Act of
            1974, as amended ("ERISA"), in connection with an employee benefit
            plan, as that term is defined by ERISA, which is sponsored by the
            Company or any of its Subsidiaries; or is or was serving at the
            request of, for the convenience of, or to represent the interests of
            the Company or a Subsidiary as a director, officer, employee or
            agent of another foreign or domestic corporation, partnership, joint
            venture, trust or other enterprise; or was a director, officer,
            employee or agent of a foreign or domestic corporation which was a
            predecessor corporation of the Company or a Subsidiary, or was a
            director, officer, employee or agent of another enterprise at the
            request of, for the convenience of, or to represent the interests of
            such predecessor corporation.

                  (b) "D&O Insurance" shall mean directors' and officers'
            liability insurance.

                  (c) "Expenses" shall include all direct and indirect costs of
            any type or nature whatsoever (including, without limitation, all
            attorneys' fees and related disbursements, other out-of-pocket costs
            and reasonable compensation for time spent by the Indemnitee for
            which he is not otherwise compensated by the Company or any third
            party) actually and reasonably incurred by the Indemnitee in
            connection with either the investigation, defense or appeal of a
            Proceeding, as hereinafter defined, or establishing or enforcing a
            right to indemnification under this Agreement, Section 145 or
            otherwise; provided, however, that unless otherwise expressly
            provided below. Expenses shall not include any judgments, fines,
            ERISA excise taxes or penalties, or amounts paid in settlement of a
            Preceding.

                  (d) "Proceeding" shall mean any threatened, pending, or
            completed action, suit or other proceeding, whether civil, criminal,
            administrative, investigative, appellate, or any other type
            whatsoever.

                  (e) "Subsidiary" shall mean any corporation of which more than
            fifty percent (50%) of the outstanding voting securities is owned
            directly or indirectly by the Company and one or more other
            Subsidiaries, or by one or more other Subsidiaries.

2. Agreement to Serve. The Indemnitee agrees to serve and/or continue to serve
as an Agent, at the will of the Company (or under separate agreement, if such
agreement exists), in the capacity Indemnitee currently serves as an Agent, so
long as he is duly appointed or elected and qualified in accordance with the
applicable provisions of the by-laws of the Company or any Subsidiary or until
such time as he tenders his resignation in writing; provided, however, that
nothing contained in this Agreement is intended to create any right to continued
employment and/or service as a director by Indemnitee.

3. Maintenance of Liability Insurance.

                  (a) The Company hereby covenants and agrees that, so long as
            the Indemnitee shall continue to serve as an Agent and thereafter so
            long as the Indemnitee shall be subject to any possible Proceeding
            by reason of the fact that the Indemnitee was an Agent, the Company,
            subject to Section 3(c), shall promptly obtain and maintain in full
            force and effect D&O Insurance in reasonable amounts from
            established and reputable insurers.

                  (b) In all policies of D&O Insurance, the Indemnitee shall be
            named as an insured in such a manner as to provide the Indemnitee
            the same rights and benefits as are accorded to the most favorably
            insured of the Company's directors, if the Indemnitee is a director,
            or of the


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            Company's officers, if the Indemnitee is not a director of the
            Company but is an officer, or of the Company's employees, if the
            Indemnitee is not an officer or director of the Company but is an
            employee of the Company, or of the Company's agents, if the
            Indemnitee is not an officer, director or employee of the Company
            but is an agent.

                  (c) Notwithstanding the foregoing, the Company shall have no
            obligation to obtain or maintain D&O insurance if the Company
            determines in good faith that such insurance is not reasonably
            available, the premium costs for such insurance are disproportionate
            to the amount of coverage provided, the coverage provided by such
            insurance is so limited by exclusions that there is insufficient
            benefit from such insurance, or the Indemnitee is covered by similar
            insurance maintained by a Subsidiary.

4. Mandatory Indemnification

                  (a) To the fullest extent not prohibited by Section 145 as in
            effect on the date of this Agreement and as may hereafter be
            amended, or any other statutory provision permitting or authorizing
            such indemnification which is adopted subsequent to the execution of
            this Agreement (but only to the extent that any such amendment or
            other provision permits the Company to provide broader
            indemnification rights than Section 145 permits prior to any such
            amendment or the adoption of any such provision), the Company shall
            indemnify and hold harmless the Indemnitee if the Indemnitee is a
            person who was or is a party or is threatened to be made a party to
            any Proceeding (including, without limitation, an action by or in
            the right of the Company) by reason of the fact that he is or was an
            Agent, or by reason of anything done or not done by him in any such
            capacity, against any and all Expenses and liabilities of any type
            whatsoever (including, but not limited to, judgments, fines, ERISA
            excise taxes or penalties, and amounts paid in settlement) actually
            and reasonably incurred by him in connection with the investigation,
            defense, settlement or appeal of such Proceeding.

                  (b) In addition to the indemnity provided by Section 4(a)
            hereof, the Company shall, subject to Section 6, 7, 8 and 10 hereof,
            indemnify and hold harmless the Indemnitee if the Indemnitee is a
            person who was or is a party or is threatened to be made a party to
            any Proceeding (including, without limitation, an action by or in
            the right of the Company) by reason of the fact that he is or was an
            Agent, or by reason of anything done or not done by him in any such
            capacity, against any and all Expenses and liabilities of any type
            whatsoever (including, but not limited to, judgments, fines, ERISA
            excise taxes or penalties, and amounts paid in settlement) actually
            and reasonably incurred by him in connection with the investigation,
            defense, settlement or appeal of such Proceeding.

                  (c) Notwithstanding the foregoing, the Company shall not be
            obligated to indemnify the Indemnitee for Expenses or liabilities of
            any type whatsoever (including, but not limited to, judgments,
            fines, ERISA excise taxes or penalties, and amounts paid in
            settlement) which have been paid directly to Indemnitee by D&O
            Insurance.

5. Partial Indemnification. If the Indemnitee is entitled under any provision of
this Agreement to indemnification by the Company for some or a portion of any
Expenses or liabilities of any type whatsoever (including, but not limited to,
judgments, fines, ERISA excise taxes or penalties, and amounts paid in
settlement) incurred by him in the investigation, defense, settlement or appeal
of a Proceeding but not entitled, however, to indemnification for all of the
total amount thereof, the Company shall indemnify the Indemnitee for such
portion thereof to which the Indemnitee is entitled.

6. Mandatory Advancement of Expenses. Subject to Section 10(a) below, the
Company shall advance all Expenses incurred by the Indemnitee in connection with
the investigation, defense, settlement or appeal or any Proceeding to which the
Indemnitee is a party or is threatened to be made a party by reason of the fact
that the Indemnitee is or was an Agent. Indemnitee hereby undertakes to repay
such amounts advanced only if, and to the extent that, it shall ultimately be
determined pursuant to Section 8 hereof that the Indemnitee is not entitled to
be


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indemnified by the Company as authorized hereby. The advances to be made
hereunder shall be paid by the Company to the Indemnitee within twenty (20) days
following delivery of a written request therefor by the Indemnitee to the
Company.

7. Notice and Other Indemnification Procedures.

                  (a) Promptly after receipt by the Indemnitee of notice of the
            commencement of or the threat of commencement of any Proceeding, the
            Indemnitee shall, if the Indemnitee believes that indemnification
            with respect thereto may be sought from the Company under this
            Agreement, notify the Company of the commencement or threat of
            commencement thereof.

                  (b) If, at the time of the receipt of a notice of the
            commencement of a Proceeding pursuant to Section 7(a) hereof, the
            Company has D&O Insurance in effect, the Company shall give prompt
            notice of the commencement of such proceeding to the insurers in
            accordance with the procedures set forth in the respective policies.
            The Company shall thereafter take all necessary or desirable action
            to cause such insurers to pay, on behalf of the Indemnitee, all
            amounts payable as a result of such Proceeding in accordance with
            the terms of such policies.

                  (c) In the event the Company shall be obligated to pay the
            Expenses of any Proceeding against the Indemnitee, the Company shall
            be entitled to assume the defense of such Proceeding, with counsel
            selected by the Company and subject to the reasonable approval of
            the Indemnitee, upon the delivery to the Indemnitee of written
            notice of its election so to do. After delivery of such notice,
            approval of such counsel by the Indemnitee and the retention of such
            counsel by the Company, the Company will not be liable to the
            Indemnitee under this Agreement for any fees of counsel subsequently
            incurred by the Indemnitee with respect to the same Proceeding,
            provided that (i) the Indemnitee shall have the right to employ his
            counsel in any such Proceeding at the Indemnitee's expense; and (ii)
            if (A) the employment of counsel by the Indemnitee has been
            previously authorized by the Company, or (B) the Indemnitee shall
            have reasonably concluded that there may be a conflict of interest
            between the Company and the Indemnitee in the conduct of any such
            defense, or (C) the Company shall not, in fact, have employed
            counsel to assume the defense of such Proceeding, the fees and
            expenses of Indemnitee's counsel shall be at the expense of the
            Company. The Company shall not be entitled to assume the defense of
            any action, suit, or proceeding by or on behalf of the Company or as
            to which the Indemnitee shall have made the conclusion provided for
            in (ii)B above.

8. Determination of Right to Indemnification.

                  (a) To the extent the Indemnitee has been successful on the
            merits or otherwise in defense of any Proceeding referred to in
            Section 4(a) or 4(b) of this Agreement or in the defense of any
            claim, issue or matter described therein, the Company shall
            indemnify the Indemnitee against Expenses actually and reasonably
            incurred by him in connection with the investigation, defense, or
            appeal of such Proceeding.

                  (b) In the event that Section 8(a) is inapplicable, the
            Company shall also indemnify the Indemnitee unless, and only to the
            extent that, the Company shall prove by clear and convincing
            evidence to a forum listed in Section 8(c) below that
            indemnification is not required pursuant to Sections 4 and 10
            hereof.

                  (c) The Indemnitee shall be entitled to select the forum in
            which the validity of the Company's claim under Section 8(b) hereof
            that the Indemnitee is not entitled to indemnification will be heard
            from among the following:

                        (1) A quorum of the Board consisting of directors who
                  are not parties to the proceeding for which indemnification is
                  being sought;


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                        (2) The stockholders of the Company;

                        (3) Legal counsel selected by the Indemnitee, and
                  reasonably approved by the Board, which counsel shall make
                  such determination in a written opinion; or

                        (4) A panel of three (3) arbitrators, one (1) of whom is
                  selected by the Company, another of whom is selected by the
                  Indemnitee and the last of whom is selected by the first two
                  (2) arbitrators so selected.

                  (d) As soon as practicable, and in no event later than thirty
            (30) days after written notice of the Indemnitee's choice of forum
            pursuant to Section 8(c) above, there shall be submitted to such
            forum as the Indemnitee or the Indemnitee's counsel may reasonably
            request, its claim that the Indemnitee is not entitled to
            indemnification, and the Company shall act in the utmost good faith
            to assure the Indemnitee a complete opportunity to defend against
            such claim.

                  (e) Notwithstanding a determination by any forum listed in
            Section 8(c) hereof that Indemnitee is not entitled to
            indemnification with respect to a specific Proceeding, the
            Indemnitee shall have the right, subject to the provisions of
            Section 18 hereof, to apply to the Court of Chancery of Delaware,
            the court in which that Proceeding is or was pending, or any other
            court of competent jurisdiction, for the purpose of enforcing the
            Indemnitee's right to indemnification pursuant to this Agreement.

                  (f) Notwithstanding any other provision in this Agreement to
            the contrary, the Company shall indemnify the Indemnitee against all
            Expenses incurred by the Indemnitee in connection with any hearing
            or Proceeding under this Section 8 involving the Indemnitee and
            against all Expenses incurred by the Indemnitee in connection with
            any other Proceeding between the Company and the Indemnitee
            involving the interpretation or enforcement of the rights of the
            Indemnitee under this Agreement unless a court of competent
            jurisdiction finds that each of the claims and/or defenses of the
            Indemnitee in any such Proceeding was frivolous or made in bad
            faith.

9. Share Ratification. Unless this Agreement in substantially the form set forth
herein has been approved by the shareholders of the Company, this Agreement
shall be expressly subject to ratification by such stockholders. If this
Agreement in substantially the form set forth herein is not so ratified and/or
approved by such stockholders within one (1) year after the effective date
hereof, this Agreement shall be void.

10. Exceptions. Any other provision herein to the contrary notwithstanding, the
Company shall not be obligated pursuant to the terms of this Agreement:

                  (a) To indemnify or advance Expenses to the Indemnitee with
            respect to Proceedings or claims initiated or brought voluntarily by
            the Indemnitee and not by way of defense, except with respect to
            Proceedings brought to establish or enforce a right to
            indemnification under this Agreement or any other statute or law or
            otherwise as required under Section 145, but such indemnification or
            advancement of Expenses may be provided by the Company in specific
            cases if the Board of Directors finds it to be appropriate; or

                  (b) To indemnify the Indemnitee for any Expenses incurred by
            the Indemnitee with respect to any Proceeding instituted by the
            Indemnitee to enforce or interpret this Agreement, if a court of
            competent jurisdiction determines that each of the material
            assertions made by the Indemnitee in such proceeding was not made in
            good faith or was frivolous; or

                  (c) To indemnify the Indemnitee under this Agreement for any
            amounts paid in settlement of a Proceeding unless the Company
            consents to such settlement, which consent shall not be unreasonably
            withheld; or


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                  (d) on account of any Proceeding in which judgment is rendered
            against Indemnitee for an accounting of profits made from the
            purchase or sale by Indemnitee of securities of the Company pursuant
            to the provisions of Section 16(b) of the Securities Exchange Act of
            1934, as amended; or

                  (e) on account of Indemnitee's conduct which is finally
            adjudged by a court to have been knowingly fraudulent, deliberately
            dishonest or willful misconduct; or

                  (f) if a final adjudication by a court having jurisdiction in
            the matter shall determine that such indemnification is not lawful.

11. Non-exclusivity. The provisions for indemnification and advancement of
Expenses set forth in this Agreement shall not be deemed exclusive of any other
rights which the Indemnitee may have under any provision of law, the Company's
certificate of incorporation or By-laws, the vote of the Company's stockholders
or disinterested directors, other agreements, or otherwise, both as to action in
his official capacity and to action in another capacity while occupying his
position as an Agent, and the Indemnitee's rights hereunder shall continue after
the Indemnitee has ceased acting as an Agent and shall inure to the benefit of
the heirs, executors and administrators of the Indemnitee or his estate.

12. Interpretation of Agreement. It is understood that the parties hereto intend
this Agreement to be interpreted and enforced so as to provide indemnification
to the Indemnitee to the fullest extent now or hereafter permitted by law.

13. Severability. If any provision or provisions of this Agreement shall be held
to be invalid, illegal or unenforceable for any reason whatsoever, (i) the
validity, legality and enforceability of the remaining provisions of the
Agreement (including without limitation, all portions of any paragraphs of this
Agreement containing any such provision held to be invalid, illegal or
unenforceable, that are not themselves invalid, illegal or unenforceable) shall
not in any way be affected or impaired thereby, and (ii) to the fullest extent
possible, the provisions of this Agreement (including, without limitation, all
portions of any paragraph of this Agreement containing any such provision held
to be invalid, illegal or unenforceable, that are not themselves invalid,
illegal or unenforceable) shall be construed so as to give effect to the intent
manifested by the provision held invalid, illegal or unenforceable and to give
effect to Section 12 hereof.

14. Modification and Waiver. No waiver, supplement, modification or amendment of
this Agreement shall be binding unless executed in writing by both of the
parties hereto. No waiver of any of the provisions of this Agreement shall be
deemed, or shall constitute, a waiver of any other provision hereof (whether or
not similar), nor shall such waiver constitute a continuing waiver.

15. Successors and Assigns. The terms of this agreement shall bind, and shall
inure to the benefit of, the successors and assigns of the Company and the
successors, assigns, heirs, executors and administrators of the Indemnitee or
his estate.

16. Notice. All notices, requests, demands and other communications under this
Agreement shall be in writing and shall be deemed duly given (i) if delivered by
hand and receipted for by the party addressee or (ii) if mailed by certified or
registered mail with postage prepaid, on the third business day after the
mailing date. Addresses for notice to either party are as follows:

      to the Company:      Ascential Software Corporation
                           50 Washington Street
                           Westboro, Massachusetts 01581
                           Attn:  Vice President, Legal, and
                           General Counsel

      to the Indemnitee:


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                           Thomas Mackiewicz
                           79 Brookdale Road
                           Sudbury, Massachusetts 01776

or subsequently modified by written notice given in accordance with this
section.

17. Governing Law. This Agreement shall be governed exclusively by and construed
according to the laws of the State of Delaware, as applied to contracts between
Delaware residents entered into and to be performed entirely within Delaware.

18. Consent to Jurisdiction. Subject to Indemnitee's right to select a
nonjudicial forum under Section 8(c) hereof, the Company and the Indemnitee each
hereby irrevocably consent to the jurisdiction of the courts of the State of
Delaware for all purposes in connection with any action or proceeding which
arises out of or relates to this Agreement and agree that any action instituted
under this Agreement shall be brought only in the state courts of the State of
Delaware.

      IN WITNESS WHEREOF, the parties hereto have entered into this Agreement
as of the date first above written,

ASCENTIAL SOFTWARE CORPORATION
a Delaware Corporation

"COMPANY"

By:   /s/ Peter Gyenes
      Peter Gyenes
      Chief Executive Officer and
      Chairman of the Board

"INDEMNITEE"

      /s/ Thomas Mackiewicz
      Thomas Mackiewicz

Approved by stockholders on February 8, 1988.


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