Release Details

CAMBRIDGE, Mass., Sep 8, 2003 (BUSINESS WIRE) -- Aspen Technology, Inc. (Nasdaq: AZPN) today announced that Mitsubishi Rayon Co., Ltd, a leading producer of acrylic products, is expanding its use of Aspen Engineering Suite (AES)(TM) solutions with a new multi-year license agreement. Under the terms of the agreement, Mitsubishi Rayon is adopting AspenTech's tools for economic evaluation to help identify optimal process designs and to make better capital investment decisions.

Mitsubishi Rayon will use the economic evaluation solutions, based on Aspen Icarus Process Evaluator(TM), to provide accurate estimates of the capital investment and operational costs associated with new or updated manufacturing processes. According to the company, the solution could shorten process cost estimation time from one month to one day, enabling its process engineers to study a much greater number of alternatives processes, and to select the process design with the lowest overall lifecycle costs.

"AspenTech's process simulation and optimization solutions are established as a clear technology leader in the chemicals industry," said Mr. Tajiri, Director of Mitsubishi Rayon. "Over the past nine years, Mitsubishi Rayon has realized significant benefits from using the Aspen Engineering Suite as a standard tool within our process development group. This new agreement will enable our process engineers to generate even greater value using a broader range of AES technologies."

Mitsubishi Rayon has used AspenTech's engineering solutions since 1994, and has used AES simulation and optimization technologies to improve the quality and efficiency of its manufacturing processes producing a range of chemicals and plastics, fibers and high-performance materials. In addition to optimizing existing processes, the company has also applied AES tools to support new process start-ups such as its methyl methacrylate (MMA) plant in Thailand and for new facilities under construction in China.

"Making the right process design and investment decisions is critical for process manufacturers," said David McQuillin, President and CEO of AspenTech. "AspenTech's economic evaluation solutions allow process engineers to develop full conceptual cost estimates quickly and accurately. This enables companies to achieve significant cost savings by ensuring the design they select provides the greatest returns on their capital investment."

About Mitsubishi Rayon

Mitsubishi Rayon Co., Ltd is a major chemicals and plastics company that is focused on two core acrylic-related businesses - the MMA Business Complex (methyl methacrylate-related products) and the AN Business Complex (acrylonitrile-related products). The company is also a major producer of acrylic fibers and textiles, including a range of products based on semi-synthetic acetate fibers. Established in 1933, the company has headquarters in Tokyo, Japan, and employs around 8,900 people worldwide. Mitsubishi Rayon operates four major production sites in Japan, and also has offices in America, Hong Kong, and Thailand. For more information, visit www.mrc.co.jp.

About AspenTech

Aspen Technology, Inc. provides industry-leading software and implementation services that enable process companies to increase efficiency and profitability. AspenTech's engineering product line is used to design and improve plants and processes, maximizing returns throughout an asset's operating life. Its manufacturing/supply chain product line allows companies to increase margins in their plants and supply chains, by managing customer demand, optimizing production, and streamlining the delivery of finished products. These two offerings are combined to create solutions for enterprise operations management (EOM), integrated enterprise-wide systems that provide process manufacturers with the capability to dramatically improve their operating performance. Over 1,500 leading companies already rely on AspenTech's software, including Aventis, Bayer, BASF, BP, ChevronTexaco, Dow Chemical, DuPont, ExxonMobil, Fluor, Foster Wheeler, 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. 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 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, Aspen Engineering Suite, Aspen Icarus Process Evaluator and the aspen leaf logo are trademarks of Aspen Technology, Inc., Cambridge, Mass.

Aspen Technology, Inc.
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