SABIC-Europe Successfully Implements AspenTech's Polymer Advanced Control Solution at Second Production Site.

CAMBRIDGE, Mass. -- Aspen Apollo(TM) non-linear controller and Aspen Transition Manager(TM) enable polyethylene plant to maximize throughput, improve quality and optimize product transitions

Aspen Technology, Inc. (Nasdaq: AZPN) today announced that SABIC-Europe has expanded its use of the Aspen Apollo advanced control solution for the polymer industry by implementing the solution at its low density polyethylene (LDPE) plant in Geleen, Netherlands. The company chose to apply Aspen Apollo after a successful implementation at SABIC's LD5 polyethylene plant in Gelsenkirchen, Germany, where the solution delivered increased throughput, improved product quality and optimized transitions.

"Our experiences in the LD5 plant, with its broad range of product types and specifications, convinced us that the AspenTech polymer advanced control solution would fulfill the needs of our plants," said Wil Ernes, plant manager LDPE, SABIC-Europe. "AspenTech's deep domain expertise and industry leading technology are essential contributory factors in the success of this project, and gave us confidence to extend our use of the solution."

The System 17 tubular high-pressure LDPE plant in Geleen is the largest such reactor in SABIC-Europe, and is based on SABIC's own patented technology. The plant produces over a dozen resin types, and supplies the majority of the company's LDPE product range with melt index between 0.3 and 65 dg/min. The Aspen Apollo non-linear control technology is integrated with Aspen Transition Manager which has already been implemented in the plant, and which successfully manages over 200 transitions a year.

"AspenTech's non-linear control solution brings faster control and greater stability to polymer processes," said Ruud Litjens, process control engineer, SABIC-Europe. "It provides the capabilities we require when exploring so many variations in process characteristic over the product range. The Aspen Apollo controller fits perfectly with the Aspen Transition Manager, giving us maximum flexibility in our operations. The robustness of the solution also results in high confidence of the operators, and demonstrates that maximization of plant output and stable, reliable production can go hand in hand."

The main drivers for SABIC-Europe to implement Aspen Apollo were to achieve a reduction of on-spec losses during in-grade control, to maximize throughput and minimize transition losses, and to successfully apply product gloss and melt index estimators so that high quality information is available for in-grade production as well as during transitions. The company also selected the solution for its flexibility in managing a broad range of polymer processes, and its ability to integrate with AspenTech's other manufacturing solutions.

"AspenTech's advanced control solution is capable of managing all types of non-linear polymer production processes," said Joep Bazelmans, process control engineer in the Manufacturing Competence Center, SABIC-Europe. "This enables us to export experiences and applications to other plants, helping us to achieve maximum site performance whilst guaranteeing low total cost of ownership. The polymer control solution also fits perfectly with AspenTech's suite of manufacturing products, allowing us to leverage a broad range of other applications including process databases, recipe management and production support tools, and interfaces to business ERP systems."

"AspenTech is proud of its ongoing relationship with SABIC, which is a leading global player in the field of petrochemicals," said Steve Pringle, Senior Vice President, AspenTech, "We are particularly excited that SABIC-Europe has implemented our non-linear control solution on yet another process technology, building further on the tremendous success that we have seen in the polymers market over the past three years."

License revenue from this project was recognized in a quarter prior to the current fiscal quarter ending December 31 2005.

About SABIC-Europe

SABIC-Europe is a SABIC subsidiary which includes all SABIC activities in Europe and employs around 2,300 people. The head office is located in Sittard (the Netherlands), and the company operates integrated world-scale production facilities for hydrocarbons and polyolefins in Geleen (the Netherlands) and polyolefins in Gelsenkirchen (Germany). Total annual polyolefin production is 2.5 million tons. For more information, visit www.sabic-europe.com.

About AspenTech

Aspen Technology, Inc. provides industry-leading software and professional services that help process companies improve efficiency and profitability by enabling them to model, manage and control their operations. AspenTech's integrated aspenONE(TM) solutions are aligned with the key industry business processes, providing manufacturers the capabilities they need to optimize operational performance, make real-time decisions and synchronize the plant and supply chain. Over 1,500 leading companies already rely on AspenTech's software, including Bayer, BASF, BP, Chevron Corporation, DuPont, ExxonMobil, Fluor, GlaxoSmithKline, Sanofi-Aventis, Shell, and Total. For more information, visit www.aspentech.com.

This press release may contain forward-looking statements for purposes of the safe harbor provisions of the Private Securities Litigation Reform Act of 1995. Actual results may vary significantly from AspenTech's expectations based on a number of risks and uncertainties, including, without limitation: AspenTech's plan to improve operational performance may not be implemented effectively; AspenTech has identified material weaknesses in its internal controls with respect to software license revenue recognition and other matters, that, if not remedied effectively, could result in material misstatements; risks around securities litigation and investigations; AspenTech's lengthy sales cycle makes it difficult to predict quarterly operating results; fluctuations in AspenTech's quarterly operating results; AspenTech's dependence on customers in the cyclical chemicals, petrochemicals and petroleum industries; the possibility of new accounting standards or the interpretation of existing accounting standards affecting our financial results; AspenTech's ability to raise additional capital as required; intense competition; AspenTech's need to develop and market products successfully; reliance on relationships with strategic partners; challenges associated with international operations; and other risk factors described from time to time in AspenTech's periodic reports filed with the Securities and Exchange Commission. AspenTech cannot guarantee any future results, levels of activity, performance, or achievements. AspenTech expressly disclaims any current intention to update forward-looking statements after the date of this press release.

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