Exhibit 10.2

Execution Version

SUBSIDIARY GUARANTEE AGREEMENT

This SUBSIDIARY GUARANTEE AGREEMENT (this “Agreement”), dated as of May 1, 2006,
is among ANSYS, INC., a Delaware corporation (the “Borrower”), each of the
Subsidiary Guarantors party hereto, any other Person (as defined in the Credit
Agreement referred to below) which may become a Subsidiary Guarantor hereunder
pursuant to a duly executed joinder agreement in the form attached as Exhibit A
hereto (each a “Subsidiary Guarantor” and, collectively, the “Subsidiary
Guarantors”) and Bank of America, N.A., as administrative agent (in such
capacity, the “Administrative Agent”) for the Lenders (as defined in the Credit
Agreement referred to below).

Reference is made to that certain Credit Agreement, dated as of May 1, 2006 (as
in effect from time to time, the “Credit Agreement”), among the Borrower, each
lender from time to time party thereto and Bank of America, N.A., as
Administrative Agent. Capitalized terms used and not defined herein (including,
without limitation, the term “Obligations”) are used with the meanings assigned
to such terms in the Credit Agreement.

The Lenders have agreed to make Loans to the Borrowers pursuant to, and upon the
terms and subject to the conditions specified in, the Credit Agreement. Each
Subsidiary Guarantor is a Subsidiary of the Borrower and acknowledges that it
has derived and will derive substantial benefit from the making of the Loans by
the Lenders to the Borrower. As consideration therefor, and in order to induce
the Lenders to make Loans, each Subsidiary Guarantor is willing to execute this
Agreement.

Accordingly, the parties hereto agree as follows:

Section 1. Guarantee. Each Subsidiary Guarantor unconditionally guarantees,
jointly with the other Loan Parties and any other guarantors of the Obligations
under the Credit Agreement and other Loan Documents, and severally, as a primary
obligor and not merely as a surety, the due and punctual payment and performance
of the Obligations. To the fullest extent permitted by applicable Law, each
Subsidiary Guarantor waives notice of, or any requirement for further assent to,
any agreements or arrangements whatsoever by the Administrative Agent, the
Lenders, and each other Indemnitee or other Persons to whom any part of the
Obligations may be owed (collectively, the “Guaranteed Parties”), with any other
Person pertaining to the Obligations, including agreements and arrangements for
payment, extension, renewal, subordination, composition, arrangement, discharge
or release of the whole or any part of the Obligations, or for the discharge or
surrender of any or all security, or for the compromise, whether by way of
acceptance of part payment or otherwise, and, to the fullest extent permitted by
applicable law, the same shall in no way impair each Subsidiary Guarantor’s
liability hereunder.

Section 2. Obligations Not Waived. To the fullest extent permitted by applicable
Law, each Subsidiary Guarantor waives presentment to, demand of payment from and
protest to the Borrower or any other Person of any of the Obligations, and also
waives

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notice of acceptance of its guarantee, notice of protest for nonpayment and all
other formalities. To the fullest extent permitted by applicable law, the
guarantee of each Subsidiary Guarantor hereunder shall not be affected by
(a) the failure of any Person to assert any claim or demand or to enforce or
exercise any right or remedy against the Borrower, any Subsidiary Guarantor or
any other Person under the provisions of the Credit Agreement, any other Loan
Document or otherwise in connection therewith; (b) any extension, renewal or
increase of or in any of the Obligations; (c) any rescission, waiver, amendment
or modification of, or any release from, any of the terms or provisions of this
Agreement, the Credit Agreement, any other Loan Document, any guarantee or any
other agreement or instrument, including with respect to any guarantor under the
Loan Documents; (d) the failure or delay of any Guaranteed Party to assert any
claim or demand, or exercise any right or remedy against any Loan Party, any
other guarantor of the Obligations or any other Person; or (e) any default,
failure or delay, willful or otherwise, in the performance of the Obligations,
or by any other act, omission or delay to do any other act that may or might in
any manner or to any extent vary the risk of any guarantor or that would
otherwise operate as a discharge of any Subsidiary Guarantor as a matter of law
or equity (other than the payment in full in cash of all the Obligations (other
than contingent indemnification obligations for which no claim has been
asserted) and the termination of all Commitments) or which would impair or
eliminate any right of any Subsidiary Guarantor to subrogation.

Section 3. Guarantee of Payment. Each Subsidiary Guarantor further agrees that
its guarantee constitutes a guarantee of payment when due and not of collection,
and, to the fullest extent permitted by applicable Law, waives any right to
require that any resort be had by the Administrative Agent or any other
Guaranteed Party to any security held for payment of the Obligations or to any
balance of any deposit account or credit on the books of the Administrative
Agent or any other Guaranteed Party in favor of the Borrower, any Subsidiary
Guarantor or any other Person.

Section 4. No Discharge or Diminishment of Guarantee; Payments. (a) To the
fullest extent permitted by applicable law and except as otherwise expressly
provided in this Agreement, the obligations of each Subsidiary Guarantor
hereunder shall not be subject to any reduction, limitation, impairment or
termination for any reason (other than the indefeasible payment in full in cash
of the Obligations (other than contingent indemnification obligations for which
no claim has been asserted) and the termination of all Commitments), and shall
not be subject to any defense (other than a defense of payment or performance)
or setoff, counterclaim, recoupment or termination whatsoever by reason of the
invalidity, illegality or unenforceability of the Obligations or otherwise.

(b) All payments hereunder shall be made without setoff or counterclaim and free
and clear of and without deduction for any taxes, levies, imposts, duties,
charges, fees, deductions, withholdings, compulsory loans, restrictions or
conditions of any nature now or hereafter imposed or levied by any jurisdiction
or any political subdivision thereof or taxing or other authority therein,
except to the extent expressly provided otherwise in Article III of the Credit
Agreement. If any Subsidiary Guarantor is compelled by law to make any such
deduction or withholding, it will make such deduction or withholding and comply
with Article III of the Credit Agreement as if the provisions of such article
applicable to the Borrower applied to such Subsidiary Guarantor. The obligations
of the Subsidiary Guarantor under this Section 4(b) shall survive the payment in
full of the Obligations and termination hereof.

 

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Section 5. Defenses Waived. To the fullest extent permitted by applicable Law,
each Subsidiary Guarantor waives any defense based on or arising out of the
unenforceability of the Obligations or any part thereof from any cause or the
cessation from any cause of the liability (other than the final and indefeasible
payment in full in cash of the Obligations (other than contingent
indemnification obligations for which no claim has been asserted) and the
termination of all Commitments) of the Borrower or any other Person. Subject to
the terms of the other Loan Documents, the Administrative Agent and the other
Indemnified Parties may, at their election, foreclose on any security held by
one or more of them by one or more judicial or nonjudicial sales, accept an
assignment of any such security in lieu of foreclosure, compromise or adjust any
part of the Obligations, make any other accommodation with any other Loan Party
or any other guarantor or exercise any other right or remedy available to them
against any other Loan Party or any other guarantor, without affecting or
impairing in any way the liability of each Subsidiary Guarantor hereunder except
to the extent the Obligations (other than contingent indemnification obligations
for which no claim has been asserted) have been fully, finally and indefeasibly
paid in cash. Pursuant to and to the fullest extent permitted by applicable Law,
each Subsidiary Guarantor waives any defense arising out of any such election
even though such election operates, pursuant to applicable Law, to impair or to
extinguish any right of reimbursement or subrogation or other right or remedy of
each Subsidiary Guarantor against any other Loan Party, any other guarantor or
any security.

Section 6. Agreement to Pay; Subordination; Waiver of Subrogation; Stay of
Acceleration.

(a) In furtherance of the foregoing and not in limitation of any other right
that the Administrative Agent or any other Indemnified Party has at law or in
equity against each Subsidiary Guarantor by virtue hereof, upon the failure of
the Borrower or any other Loan Party to pay any Obligation when and as the same
shall become due, whether at maturity, by acceleration, or otherwise, each
Subsidiary Guarantor hereby promises to and will forthwith pay, or cause to be
paid, to the Administrative Agent or such other Indemnified Party as designated
thereby in cash an amount equal to the unpaid principal amount of such
Obligations then due, together with any accrued and unpaid interest on such
Obligations.

(b) Upon payment by each Subsidiary Guarantor of any sums to the Administrative
Agent or any Indemnified Party as provided above, all rights of each Subsidiary
Guarantor against the Borrowers arising as a result thereof by way of right of
subrogation, contribution, reimbursement, indemnity or otherwise shall in all
respects be subordinate and junior in right of payment to the prior indefeasible
payment in full in cash of all the Obligations and no Subsidiary Guarantor shall
exercise any such rights with respect to any payments it makes hereunder until
all of the Obligations have been paid in full in cash and all Commitments have
been terminated. In addition, any indebtedness or other obligations of the
Borrower or any Subsidiary now or hereafter held by each Subsidiary Guarantor is
hereby subordinated in right of payment to the prior payment in full of the
Obligations. If any amount shall be paid to any Subsidiary Guarantor on account
of (i) such subrogation, contribution,

 

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reimbursement, indemnity or similar right or (ii) any such indebtedness or other
obligations at any time when any Obligation then due and owing has not been paid
in full in cash, such amount shall be held in trust for the benefit of the
Indemnified Parties and shall forthwith be paid to the Administrative Agent to
be credited against the payment of the Obligations, whether matured or
unmatured, in accordance with the terms of the Loan Documents.

(c) In the event that acceleration of the time for payment of any of the
Obligations is stayed, in connection with any case commenced by or against any
Loan Party or any other Person under any Debtor Relief Laws or otherwise, all
such amounts shall nonetheless be payable by the Subsidiary Guarantors
immediately upon demand.

Section 7. General Limitation on Guarantee Obligations. In any action or
proceeding involving any state corporate law, or any Debtor Relief Law, if the
obligations of any Subsidiary Guarantor under this Agreement would otherwise be
held or determined to be void, voidable, invalid or unenforceable, or
subordinated to the claims of any other creditors, on account of the amount of
its liability under this Agreement, then, notwithstanding any other provision to
the contrary, the amount of such liability shall, without any further action by
any Loan Party, any creditor or any other Person, be automatically limited and
reduced to the highest amount that is valid and enforceable and not subordinated
to the claims of other creditors as determined in such action or proceeding.

Section 8. Information. Each Subsidiary Guarantor assumes all responsibility for
being and keeping itself informed of the Borrower’s financial condition and
assets, all other circumstances bearing upon the risk of nonpayment of the
Obligations and the nature, scope and extent of the risks that such Subsidiary
Guarantor assumes and incurs hereunder and agrees that none of the
Administrative Agent or the other Guaranteed Parties will have any duty to
advise such Subsidiary Guarantor of information known to it or any of them
regarding such circumstances or risks.

Section 9. Covenant; Representations and Warranties. Each Subsidiary Guarantor
agrees and covenants to, and to cause each of its Subsidiaries to, take, or
refrain from taking, each action that is necessary to be taken or not taken, so
that no breach of the agreements and covenants contained in the Credit Agreement
pertaining to actions to be taken, or not taken, by such Subsidiary Guarantor or
such Subsidiary will result. Each Subsidiary Guarantor represents and warrants
as to itself that all representations and warranties relating to it contained in
the Credit Agreement are true and correct in all material respects (except to
the extent such representation and warranty is qualified as to materiality, in
which case each such representation and warranty is true and correct in all
respects, as so qualified).

Section 10. Termination. When all the Obligations (other than contingent
indemnity obligations for which no claim has been asserted) have been paid in
full and in cash and the Commitments of the Lenders shall have terminated, this
Agreement shall terminate with no action required by the parties hereto;
provided that this Agreement shall continue to be effective or be reinstated, as
the case may be, if at any time any payment, or any part thereof, on any
Obligation is rescinded or must otherwise be restored by any Indemnified Party
upon the bankruptcy or reorganization of any Borrower, any other Loan Party or
otherwise.

 

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Section 11. Binding Effect; Several Agreement; Assignments; Releases. Whenever
in this Agreement any of the parties hereto is referred to, such reference shall
be deemed to include the successors and assigns of such party; and all
covenants, promises and agreements by or on behalf of each Subsidiary Guarantor
that are contained in this Agreement shall bind and inure to the benefit of each
party hereto and their respective successors and assigns. This Agreement shall
become effective as to each Subsidiary Guarantor when a counterpart hereof
executed on behalf of each Subsidiary Guarantor shall have been delivered to the
Administrative Agent and a counterpart hereof shall have been executed on behalf
of the Administrative Agent, and thereafter shall be binding upon each
Subsidiary Guarantor and the Administrative Agent and their respective
successors and assigns, and shall inure to the benefit of each Subsidiary
Guarantor, the Administrative Agent and the other Guaranteed Parties, and their
respective successors and assigns, except that neither the Borrower nor any
Subsidiary Guarantor shall have the right to assign its rights or obligations
hereunder or any interest herein (and any such attempted assignment shall be
void) without the prior written consent of the Administrative Agent and the
Required Lenders. The Administrative Agent is hereby expressly authorized to,
and agrees upon request of the Borrower it will, release any Subsidiary
Guarantor from its obligations hereunder in the event that all the Equity
Interests of such Subsidiary Guarantor shall be sold, transferred or otherwise
disposed of, whether by merger, consolidation or otherwise, to a person other
than the Borrower or any of its Subsidiaries in a transaction permitted by the
Credit Agreement. The Administrative Agent will, at such Subsidiary Guarantor’s
expense, execute and deliver to such Subsidiary Guarantor such documents as such
Subsidiary Guarantor shall reasonably request to evidence the release of such
Subsidiary Guarantor pursuant to this Section 11.

Section 12. Waivers; Amendment. (a) No failure or delay of the Administrative
Agent in exercising any power or right hereunder shall operate as a waiver
thereof, nor shall any single or partial exercise of any such right or power, or
any abandonment or discontinuance of steps to enforce such a right or power,
preclude any other or further exercise thereof or the exercise of any other
right or power. The rights and remedies of the Administrative Agent hereunder
and of the other Guaranteed Parties under the other Loan Documents are
cumulative and are not exclusive of any rights or remedies that they would
otherwise have. No waiver of any provision of this Agreement or consent to any
departure by any Subsidiary Guarantor therefrom shall in any event be effective
unless the same shall be permitted by subsection (b) below, and then such waiver
or consent shall be effective only in the specific instance and for the purpose
for which given. No notice or demand on any Subsidiary Guarantor in any case
shall entitle such Subsidiary Guarantor to any other or further notice or demand
in similar or other circumstances.

(b) Neither this Agreement nor any provision hereof may be waived, amended or
modified except pursuant to a written agreement entered into between the
Borrower, any affected Subsidiary Guarantor and the Administrative Agent (with
the consent of the Lenders to the extent required under the Credit Agreement).

 

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Section 13. GOVERNING LAW. THIS AGREEMENT SHALL BE GOVERNED BY, AND CONSTRUED IN
ACCORDANCE WITH, THE LAWS OF THE STATE OF NEW YORK.

Section 14. Notices. All communications and notices hereunder shall be in
writing and given as provided in Section 10.02 of the Credit Agreement. All
communications and notices hereunder to each Subsidiary Guarantor shall be given
to it at its respective address set forth in Schedule I with a copy to the
Borrower.

Section 15. Survival of Agreement; Severability. (a) All covenants, agreements,
representations and warranties made by the Borrower and the Subsidiary
Guarantors herein and in the certificates or other instruments prepared or
delivered in connection with or pursuant to this Agreement or any other Loan
Document shall be considered to have been relied upon by the Administrative
Agent and the other Guaranteed Parties and shall survive the making by the
Lenders of the Loans regardless of any investigation made by the Indemnified
Parties or on their behalf, and shall continue in full force and effect until
this Subsidiary Guarantee is terminated pursuant to Section 10 hereof.

(b) In the event any one or more of the provisions contained in this Agreement
or in any other Loan Document 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 (it being understood that the invalidity of a particular
provision in a particular jurisdiction shall not in and of itself affect the
validity of such provision in any other jurisdiction). 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.

Section 16. Counterparts. This Agreement may be executed in counterparts, each
of which shall constitute an original, but all of which when taken together
shall constitute a single contract, and shall become effective as provided in
Section 11. Delivery of an executed signature page to this Agreement by
facsimile transmission shall be as effective as delivery of a manually executed
counterpart of this Agreement.

Section 17. Rules of Interpretation. The rules of interpretation specified in
Section 1.02 of the Credit Agreement shall be applicable to this Agreement.

Section 18. Jurisdiction; Consent to Service of Process. (a) Each party hereto
hereby irrevocably and unconditionally submits, for itself and its property, to
the nonexclusive jurisdiction of any New York State court or federal court of
the United States of America sitting in New York City, and any appellate court
from any thereof, in any action or proceeding arising out of or relating to this
Agreement or the other Loan Documents, or for recognition or enforcement of any
judgment, and each of the parties hereto hereby irrevocably and unconditionally
agrees that all claims in respect of any such action or proceeding may be heard
and determined in such New York State court or, to the extent permitted by law,
in such Federal court. Each of the parties hereto agrees that a final judgment
in any such action or

 

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proceeding shall be conclusive and may be enforced in other jurisdictions by
suit on the judgment or in any other manner provided by law. Nothing in this
Agreement shall affect any right that the Administrative Agent or any other
Indemnified Party may otherwise have to bring any action or proceeding relating
to this Agreement or the other Loan Documents against each Subsidiary Guarantor
or its properties in the courts of any jurisdiction.

(b) Each party hereto hereby irrevocably and unconditionally waives, to the
fullest extent it may legally and effectively do so, any objection that it may
now or hereafter have to the laying of venue of any suit, action or proceeding
arising out of or relating to this Agreement or the other Loan Documents in any
such New York State or federal court. Each of the parties hereto hereby
irrevocably waives, to the fullest extent permitted by law, the defense of an
inconvenient forum to the maintenance of such action or proceeding in any such
court.

(c) Each party to this Agreement irrevocably consents to service of process in
the manner provided for notices in Section 14. Nothing in this Agreement will
affect the right of any party to this Agreement to serve process in any other
manner permitted by law.

Section 19. Waiver of Jury Trial. EACH PARTY HERETO HEREBY WAIVES, TO THE
FULLEST EXTENT PERMITTED BY APPLICABLE LAW, ANY RIGHT IT MAY HAVE TO A TRIAL BY
JURY IN RESPECT OF ANY LITIGATION DIRECTLY OR INDIRECTLY ARISING OUT OF, UNDER
OR IN CONNECTION WITH THIS AGREEMENT OR THE OTHER LOAN DOCUMENTS. EACH PARTY
HERETO (A) CERTIFIES THAT NO REPRESENTATIVE, AGENT OR ATTORNEY OF ANY OTHER
PARTY HAS REPRESENTED, EXPRESSLY OR OTHERWISE, THAT SUCH OTHER PARTY WOULD NOT,
IN THE EVENT OF LITIGATION, SEEK TO ENFORCE THE FOREGOING WAIVER AND
(B) ACKNOWLEDGES THAT IT AND THE OTHER PARTIES HERETO HAVE BEEN INDUCED TO ENTER
INTO THIS AGREEMENT AND THE OTHER LOAN DOCUMENTS, AS APPLICABLE, BY, AMONG OTHER
THINGS, THE MUTUAL WAIVERS AND CERTIFICATIONS IN THIS SECTION 19.

Section 20. Right of Setoff. If an Event of Default shall have occurred and be
continuing, each Guaranteed Party and each affiliate of each Guaranteed Party is
hereby authorized at any time and from time to time, to the fullest extent
permitted by law, to set off and apply any and all deposits (general or special,
time or demand, provisional or final and in whatever currency) at any time held
and other Indebtedness at any time owing by such Guaranteed Party to or for the
credit or the account of each Subsidiary Guarantor against any or all the
obligations of such Subsidiary Guarantor now or hereafter existing under this
Agreement and the other Loan Documents held by such Guaranteed Party,
irrespective of whether or not the Administrative Agent or any Guaranteed Party
shall have made any demand under this Agreement or any other Loan Document and
although such obligations may be contingent, unmatured or secured or are owed to
a branch or office of such Guaranteed Party different from the branch or office
holding such deposit or obligated on such Indebtedness. Each Guaranteed Party
agrees promptly to notify such Subsidiary Guarantor and the Administrative Agent
after any such setoff and application; provided that failure to give such notice
shall not affect the validity of such setoff and application. The rights of each
Guaranteed Party and each affiliate of each Guaranteed Party under this
Section 20 are in addition to other rights and remedies (including other rights
of setoff) which such Guaranteed Party or affiliate may have.

 

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Section 21. Currency. Payments under this Subsidiary Guarantee shall be in
Dollars. If any claim arising under or related to this Subsidiary Guarantee is
reduced to judgment denominated in a currency (the “Judgment Currency”) other
than the currencies in which the Obligations are denominated or the currencies
payable hereunder (collectively, the “Obligations Currency”), the judgment shall
be for the equivalent in the Judgment Currency of the amount of the claim
denominated in the Obligations Currency included in the judgment, determined as
of the date of judgment. The equivalent of any Obligations Currency amount in
any Judgment Currency shall be calculated at the spot rate for the purchase of
the Obligations Currency with the Judgment Currency quoted by Bank of America in
the place of Bank of America’s choice at or about 8:00 a.m. on the date for
determination specified above. The Subsidiary Guarantors shall jointly and
severally indemnify the Indemnified Parties and hold the Indemnified Parties
harmless from and against all loss or damage resulting from any change in
exchange rates between the date any claim is reduced to judgment and the date of
payment thereof by the Subsidiary Guarantors or any failure of the amount of any
such judgment to be calculated as provided in this paragraph.

[Signature Pages Follow]

 

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[Signature Page to Subsidiary Guarantee Agreement]

IN WITNESS WHEREOF, the parties hereto have duly executed this Guarantee
Agreement as of the day and year first above written.

 

BORROWER: ANSYS, INC. By:  

/s/ James E. Cashman III

  James E. Cashman III   President and Chief Executive Officer SUBSIDIARY
GUARANTORS: CENTURY DYNAMICS, INC. By:  

/s/ Naury Birnbaum

  Naury Birnbaum   Chief Executive Officer SAS IP, INC. By:  

/s/ Maria T. Shields

  Maria T. Shields   President AAVID THERMAL TECHNOLOGIES, INC. By:  

/s/ James E. Cashman III

  James E. Cashman III   President

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[Signature Page to Subsidiary Guarantee Agreement]

 

ANSYS XL, LLC By:  

/s/ James E. Cashman III

  James E. Cashman III   President FLUENT INC. By:  

/s/ H. Ferit Boysan

  H. Ferit Boysan   President

 

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[Signature Page to Subsidiary Guarantee Agreement]

 

ADMINISTRATIVE AGENT: BANK OF AMERICA, N.A., as Administrative Agent By:  

/s/ John B. Desmond

  John B. Desmond   Managing Director

 

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