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Exhibit 10.42

ASPEN TECHNOLOGY, INC.

Terms and Conditions of Restricted Stock Unit Agreement
Granted Under 2010 Equity Incentive Plan

        1.    Grant of Award.    

        These terms and conditions, together with the notice of grant attached
hereto ("Notice"), evidence the grant by Aspen Technology, a Delaware
corporation (the "Company"), on the grant date set forth in the Notice (the
"Grant Date") to the individual named in the Notice (the "Participant") of
restricted stock units of the Company (individually, an "RSU" and collectively,
the "RSUs") on the terms provided herein and in the Company's 2010 Equity
Incentive Plan (the "Plan"). Each RSU represents the right to receive one share
of the common stock, $0.10 par value per share, of the Company ("Common Stock")
as provided in this Agreement. The shares of Common Stock that are issuable upon
vesting of the RSUs are referred to in this Agreement as "Shares."

        2.    Vesting; Forfeiture.    

        (a)   The RSUs shall vest according to the schedule set forth on the
Notice.

        (b)   Except as otherwise provided in the Plan, by the Board of
Directors or pursuant to agreement between the Company and the Participant, if
the Participant's employment with the Company terminates for any reason, any
portion of this award that is not vested as of the date of such termination
shall be forfeited. For purposes of this Agreement, employment with the Company
shall include employment with a parent or subsidiary of the Company.

        3.    Distribution of Shares.    

        (a)   The Company will distribute to the Participant (or to the
Participant's estate in the event that his or her death occurs after a vesting
date but before distribution of the corresponding Shares), as soon as
administratively practicable after each vesting date (each such date of
distribution hereinafter referred to as a "Settlement Date"), all of the vested
Shares of Common Stock represented by RSUs that vested before the Settlement
Date. If a Settlement Date occurs during a period during which the Participant
may not trade in securities of the Company because the Company's insider trading
policy imposes a trading blackout on the Participant, then the Settlement Date
shall be delayed until such trading blackout has ended, unless Company deducts
and retains from the Shares to be distributed upon the Settlement Date, such
number of Shares as is equal in value to the Company's statutory withholding
obligations with respect to the income recognized by Participant upon the lapse
of the forfeiture provisions set forth in the Agreement (based on statutory
withholding rates for Federal and state tax purposes, including payroll taxes,
that are applicable to such income), and to pay the required amounts to the
relevant taxing authorities.

        (b)   The Company shall not be obligated to issue to the Participant the
Shares upon the vesting of any RSU (or otherwise) unless the issuance and
delivery of such Shares shall comply with all relevant provisions of law and
other legal requirements including, without limitation, any applicable federal
or state securities laws and the requirements of any stock exchange upon which
shares of Common Stock may then be listed.

        4.    Restrictions on Transfer.    

        The Participant shall not sell, assign, transfer, pledge, hypothecate or
otherwise dispose of, by operation of law or otherwise (collectively "transfer")
any RSUs, or any interest therein, except by will or the laws of descent and
distribution.

        5.    Dividend and Other Shareholder Rights.    

        Except as set forth in the Plan, neither the Participant nor any person
claiming under or through the Participant shall be, or have any rights or
privileges of, a stockholder of the Company in respect of

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the Shares issuable pursuant to the RSUs granted hereunder until the Shares have
been delivered to the Participant.

        6.    Provisions of the Plan; Reorganization Event; Change in Control
Event.    

        This Agreement is subject to the provisions of the Plan, a copy of which
is furnished to the Participant with this Agreement.

        7.    Withholding Taxes; Section 83(b) Election.    

        (a)   No Shares will be delivered pursuant to the vesting of an RSU
unless and until the Participant pays to the Company, or makes provision
satisfactory to the Company for payment of, any federal, state or local
withholding taxes required by law to be withheld in respect of the vesting of
the RSU. To satisfy any such tax obligation, the Company may deduct and retain
from the Shares to be distributed upon the Settlement Date such number of Shares
as is equal in value to the Company's minimum statutory withholding obligations
with respect to the income recognized by the Participant upon the lapse of the
forfeiture provisions (based on minimum statutory withholding rates for federal
and state tax purposes, including payroll taxes, that are applicable to such
income), and pay the required amounts to the relevant taxing authorities.

        (b)   The Participant acknowledges that no election under Section 83(b)
of the Internal Revenue Code of 1986 may be filed with respect to this award.

        8.    Miscellaneous.    

        (a)    No Rights to Employment.    The Participant acknowledges and
agrees that the vesting of the RSUs shall be in accordance with the vesting
schedule set forth in the Notice, and is contingent upon status as an employee
at the time of vesting at the will of the Company (not through the act of being
hired). The Participant further acknowledges and agrees that the transactions
contemplated hereunder and the vesting schedule set forth in the Notice do not
constitute an express or implied promise of continued engagement as an employee
or consultant for the vesting period, for any period, or at all.

        (b)    Severability.    The invalidity or unenforceability of any
provision of this Agreement shall not affect the validity or enforceability of
any other provision of this Agreement, and each other provision of this
Agreement shall be severable and enforceable to the extent permitted by law.

        (c)    Waiver.    Any provision for the benefit of the Company contained
in this Agreement may be waived, either generally or in any particular instance,
by the Board of Directors of the Company.

        (d)    Binding Effect.    This Agreement shall be binding upon and inure
to the benefit of the Company and the Participant and their respective heirs,
executors, administrators, legal representatives, successors and assigns,
subject to the restrictions on transfer set forth in Section 4 of this
Agreement.

        (e)    Notice.    All notices required or permitted hereunder shall be
in writing and deemed effectively given upon personal delivery or five days
after deposit in the United States Post Office, by registered or certified mail,
postage prepaid, addressed to the other party hereto at the address shown
beneath his or its respective signature to this Agreement, or at such other
address or addresses as either party shall designate to the other in accordance
with this Section 8(e).

        (f)    Pronouns.    Whenever the context may require, any pronouns used
in this Agreement shall include the corresponding masculine, feminine or neuter
forms, and the singular form of nouns and pronouns shall include the plural, and
vice versa.

        (g)    Entire Agreement.    This Agreement and the Plan constitute the
entire agreement between the parties, and this Agreement supersedes all prior
agreements and understandings, relating to the subject matter of this Agreement.

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        (h)    Amendment.    This Agreement may be amended or modified only by a
written instrument executed by both the Company and the Participant.

        (i)    Governing Law.    This Agreement shall be construed, interpreted
and enforced in accordance with the internal laws of the State of Delaware, USA
without regard to any applicable conflicts of laws principles.

        (j)    Participant's Acknowledgments.    The Participant acknowledges
that he or she: (i) has read this Agreement; (ii) understands the terms and
consequences of this Agreement; and (iii) is fully aware of the legal and
binding effect of this Agreement.

        (k)    Unfunded Rights.    The right of the Participant to receive
Common Stock pursuant to this Agreement is an unfunded and unsecured obligation
of the Company. The Participant shall have no rights under this Agreement other
than those of an unsecured general creditor of the Company.

        (l)    Section 409A.    Payments under this Agreement are intended to be
exempt from, or comply with, the provisions of Section 409A of the Internal
Revenue Code of 1986 ("Section 409A") and this Agreement shall be administered
and construed accordingly. If any payment, compensation or other benefit
provided to the Participant in connection with a termination of his employment
is determined, in whole or in part, to constitute "nonqualified deferred
compensation" within the meaning of Section 409A and the Participant is a
specified employee as defined in Section 409A(2)(B)(i), no part of such payments
shall be paid before the day that is six (6) months plus one (1) day after the
date of termination (the "New Payment Date"). The aggregate of any payments that
otherwise would have been paid to the Participant during the period between the
date of termination and the New Payment Date shall be paid to the Participant in
a lump sum on such New Payment Date.

  ASPEN TECHNOLOGY, INC.

 

By:

 

 

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Mark E. Fusco
President and CEO

By accepting this grant online, I hereby acknowledge that I have read these
Terms and Conditions, the 2010 Equity Incentive Plan and related prospectus, and
agree to all terms and conditions set forth therein.

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Exhibit 10.42

ASPEN TECHNOLOGY, INC. Terms and Conditions of Restricted Stock Unit Agreement
Granted Under 2010 Equity Incentive Plan