Release Details

CAMBRIDGE, Mass.--(BUSINESS WIRE)--Nov. 17, 2004-- Aspen Technology, Inc. (Nasdaq: AZPN) today announced that Bayer Technology Services (BTS), the engineering spin-off company of the Bayer Group, has extended its commitment to AspenTech's engineering solutions by signing a new multi-year software license agreement. BTS serves as the technological backbone of Bayer, a major global polymers, pharmaceutical and cropscience company. The new agreement provides BTS with worldwide access to key aspenONE Engineering and Innovation solutions including the modules for Simulation & Optimization, Conceptual Design, and Economic Evaluation. These solutions will help Bayer optimize process performance, reduce time-to-market and maximize returns from its manufacturing assets.

Bayer has been a long-time user of AspenTech's modeling solutions, which are established as the company's standard platform for the design and optimization of petrochemical, polymer and pharmaceutical plants. The solutions provide the company with an integrated suite to optimize the performance of processes through their entire lifecycle, from conceptual design, through operations, to de-bottlenecking and process improvement.

"AspenTech is a strategic supplier of software to Bayer and its engineering solutions play a key role in helping us to improve the returns from our plant assets," said Dr. Wolfram Wagner, Managing Director of Bayer Technology Services. "By adopting a 'lifecycle modeling' approach, we are able to extend the value of models beyond the design and engineering stages, and gain significant benefits in operations, where models can provide a vital tool to support decision-making. Using the solutions to capture process knowledge in a consistent set of models also enables us to drive internal collaboration and workflow efficiencies."

Bayer Technology Services provides Bayer's internal organization and external customers with a comprehensive range of technical services across the plant lifecycle. The new agreement is based on a token system, enabling BTS to improve its service delivery through flexible access to the full range of solutions. The agreement also makes provision for the forthcoming divestment of Bayer's chemical assets to a new company, Lanxess.

"Bayer and AspenTech share a similar vision of using process models to deliver value throughout the life of a manufacturing plant," said David McQuillin, President and CEO of AspenTech. "This new agreement will enable Bayer to extend its model-centric approach, applying AspenTech's integrated solutions to streamline internal processes, reduce capital investment costs and improve operational performance."

About Bayer Technology Services

Bayer Technology Services offers integral solutions for the entire life cycle of processes and plants: from product and process development, through unit engineering and construction, to plant and process automation and optimization. Established in the course of the reorganization of the Bayer Group the new Bayer company employs around 2,300 experts around the world, with headquarters in Leverkusen (Germany), and regional offices in Baytown (Texas, USA), Antwerp (Belgium), Mexico City (Mexico) and Shanghai (People's Republic of China). Including utilities procurement for all Bayer sites in Germany, Bayer Technology Services generated revenues in 2003 of EUR 720 million. For further details, visit www.bayertechnology.com.

Bayer is a research-based, growth-oriented global enterprise with core competencies in the fields of health care, nutrition and innovative materials. It is represented by some 350 companies employing 115,400 people on all continents (as of December 31, 2003), with major business activities in Europe, North America and the Far East. In its 2003 fiscal year Bayer had net sales of EUR 28.5 billion. For more information, visit www.bayer.com.

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. The first comprehensive offering to address the demands of the Enterprise Operations Management (EOM) market, 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.

Certain paragraphs of this press release contain forward-looking statements for purposes of the safe harbor provisions of the Private Securities Litigation Reform Act of 1995, particularly the first paragraph. For this purpose, any statement using the term "will," "should," "could," "anticipates," "believes" or a comparable term is a forward-looking statement. Actual results may vary significantly from AspenTech's expectations based on a number of risks and uncertainties, including: AspenTech's ability to make its revenue goals; AspenTech's lengthy sales cycle which makes it difficult to predict quarterly operating results; fluctuations in AspenTech's quarterly operating results; AspenTech's dependence on customers in cyclical industries; adverse global economic conditions; AspenTech's ability to raise additional capital as required; the FTC's investigation of the Hyprotech acquisition; the outcome of AspenTech's restructuring plans; intense competition; AspenTech's need to develop and market products successfully; and other risk factors described from time to time in AspenTech's periodic reports and registration statements filed with the Securities and Exchange Commission. AspenTech cannot guarantee any future results, levels of activity, performance, or achievements. Moreover, neither AspenTech nor anyone else assumes responsibility for the accuracy and completeness of any forward-looking statements. AspenTech undertakes no obligation to update any of the forward-looking statements after the date of this press release.

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

CONTACT:
For Media:
Aspen Technology, Inc.
Robin Swanger, 218-504 3256
robin.swanger@aspentech.com

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