Aspen Technology Announces Webcast of Annual Shareholder Meeting; Shareholder meeting will be held on Thursday, May 26, 2005 at 3:00 p.m. ET

April 25, 2005

CAMBRIDGE, Mass.--(BUSINESS WIRE)--April 25, 2005--Aspen Technology, Inc. (Nasdaq:AZPN) today announced that the Company will webcast its annual shareholder meeting, which will be held on Thursday, May 26, 2005 in Boston, Massachusetts. Mark Fusco, President & CEO of AspenTech, will provide an overview of the Company's operational and financial performance and discuss AspenTech's strategic direction. Additional information about the Company's annual meeting can be found in the proxy statement filed on April 18, 2005 with the Securities and Exchange Commission. The webcast will be open to interested parties by accessing the Investor Relations section of the company's website at http://www.aspentech.com and clicking on the webcast hyperlink.

What: Aspen Technology's Annual Shareholder Meeting

When: Thursday, May 26, 2005, 3:00 p.m. ET

Where: http://www.aspentech.com; or in person at 60 State Street, Boston, MA

How: Live over the Internet - Access the call through the AspenTech homepage

Contact: Joshua Young, Director of Investor Relations, Aspen Technology, Inc.

If you are unable to listen to the live Webcast, the call will be archived on the Investor Relations section of AspenTech's website at the conclusion of the meeting.

About AspenTech

Aspen Technology, Inc. provides industry-leading software and implementation services that enable process companies to use simulation models to increase efficiency and profitability.

aspenONE, a new generation of software solutions from AspenTech, represents a major step forward in helping process manufacturers achieve their strategic operational excellence initiatives. aspenONE provides companies with integrated systems that enable them to manage and optimize their operational performance. Over 1,500 leading companies already rely on AspenTech's software, including Aventis, Bayer, BASF, BP, ChevronTexaco, Dow Chemical, DuPont, ExxonMobil, Fluor, GlaxoSmithKline, Shell, and Total. For more information, visit www.aspentech.com.

AspenTech, aspenONE, and the aspen leaf logo are trademarks of Aspen Technology, Inc., Cambridge, Mass.

CONTACT:
Aspen Technology, Inc.
Joshua Young, 617-949-1274
joshua.young@aspentech.com