ASPEN TECHNOLOGY TO ACQUIRE INDUSTRIAL SYSTEMS, INC., A LEADING SUPPLIER OF OPEN SYSTEMS PROCESS INFORMATION MANAGEMENT SOFTWARE; Acquisition Enhances AspenTech's Suite of Products.

CAMBRIDGE, Mass.--(BUSINESS WIRE)--April 25, 1995 -- Aspen Technology, Inc. (NASDAQ: AZPN) today announced that it has signed a definitive agreement to acquire Industrial Systems, Inc. (ISI), a leading supplier of open systems Process Information Management (PIM) software for large-scale process manufacturing environments.

PIM solutions enable manufacturing enterprises to collect, store and distribute real-time and historical process information for reporting, analysis and supervisory control. AspenTech intends both to continue to market ISI's products on a stand-alone basis and to integrate ISI's PIM software with AspenTech's modeling tools in order to provide a new class of value-added applications.

"We are very excited about the opportunities this acquisition presents," commented Larry Evans, AspenTech chairman and chief executive officer. "ISI's technology, products and expertise will significantly enhance our presence in the emerging and important online market within the process manufacturing industries."

Evans continued, "With this combination, engineers will be able to model optimal process designs, while plant managers also will be able to measure how closely actual plants are performing to these theoretical benchmarks. This is of tremendous value to our customers and will provide an important new source of competitive distinction. We believe ISI technology will be of benefit to nearly all of our customers. In addition, ISI's strong customer base will bolster AspenTech's penetration of the petroleum, food, and pulp and paper segments."

ISI's flagship product, CIM/21, has been installed in more than 130 industrial customer sites and is the leading UNIX-based open systems solution for the PIM market. ISI's customers include BASF, Boeing, Chevron, General Mills, Monsanto and Weyerhauser.

"ISI historically has focused most of its sales and marketing efforts in North America and has had sufficient resources only to react to evaluations in progress," commented Max Morgan, ISI President. "We will be able to benefit immediately from AspenTech's broad set of customer relationships and its extensive international presence. In addition, we look forward to taking advantage of technical synergies in providing a joint suite of integrated products on top of CIM/21 technology."

Evans concluded, "We anticipate that the effect on earnings per share for fiscal 1996 will be non-dilutive. Given ISI's historical revenue growth and profitability, as well as their momentum in the marketplace, we are enthusiastic about the immediate and long-term potential of this merger."

AspenTech expects to issue approximately 660,000 new shares of common stock to ISI's shareholders, and the transaction is expected to be accounted for as a pooling of interests. The transaction is subject to a final financial audit and is anticipated to close within 30 days. Privately held and based in Bothell, Washington, ISI posted revenue for the 12 months ended March 31, 1995, of approximately $8 million and was profitable.

ISI will operate as a wholly owned subsidiary of AspenTech and will continue to be located in Bothell. ISI's founders, Max Morgan and Wayne Martin, will assume positions of vice president at AspenTech, reporting to AspenTech Senior Vice President of Marketing and New Businesses, Joel Rosen.

Separately, AspenTech today reported net income for the third fiscal quarter ended March 31, 1995, of $1.6 million, an increase of 37 percent over net income of $1.1 million in the comparable quarter in fiscal 1994. Earnings per share was $0.20 in the third quarter fiscal 1995, versus $0.19 for the third quarter of last year. Weighted average shares outstanding for the quarter were 7.7 million, 29 percent greater than the 5.9 million shares outstanding for the comparable period a year ago. Revenues for the third quarter of fiscal 1995 increased 24 percent to $12.5 million from $10.1 million in the third quarter of fiscal 1994.

Aspen Technology, Inc. is a leading supplier of computer-aided chemical engineering (CACHE) software for the process manufacturing industries such as chemical, petroleum, pharmaceutical, electric power and metals/minerals. The company provides a suite of products which enable chemical engineers to model, simulate and optimize their production processes. This type of comprehensive simulation enables customers to reduce raw material, energy and capital expenses, to meet environmental and safety regulations, to improve product quality and to shorten the time required to get new production processes on stream, thus enhancing the effectiveness of chemical engineers in designing and improving process manufacturing facilities. Aspen Technology, Inc. is headquartered in Cambridge, Massachusetts.

CONTACT: Mary A. Dean

Aspen Technology, Inc.

[phone]