ASPEN TECHNOLOGY, INC. Restricted Stock Unit Agreement Granted Under 2005 Stock Incentive Plan

Exhibit 10.9

ASPEN TECHNOLOGY, INC.

Restricted Stock Unit Agreement
Granted Under 2005 Stock Incentive Plan

1.   Grant of Award.

This Agreement evidences the grant by Aspen Technology, a Delaware corporation (the “Company”) on ___________, 200  (the “Grant Date”) to ____________  (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 2005 Stock 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)    This award shall not begin to vest unless the Company is profitable for its fiscal year ending on June 30, 2007; if the Company is not profitable for such period, this award shall be null and void. This award shall vest as to 25% of the original number of RSUs on the date upon which the earnings for such fiscal year are announced (the “First Vesting Date”) and as to an additional 6.25% of the original number of RSUs on the 20th business day of each fiscal quarter thereafter until this award is fully vested on the third anniversary of the First Vesting Date (the “Final Vesting Date”).

(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.

(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.

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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 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.