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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