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                                                                   Exhibit 10.26

                               INDEMNITY AGREEMENT

         THIS INDEMNITY AGREEMENT (the "Agreement"), made and entered into this
20th day of August, 2001, 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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                               Scott N. Semel
                               54 Knobhill Street
                               Sharon, Massachusetts 02067

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/ Scott N. Semel
        Scott N. Semel

Approved by stockholders on February 8, 1988.



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