Exhibit 99.1 SECURITIES PURCHASE AGREEMENT by and among ASPEN TECHNOLOGY, INC. and THE SEVERAL PURCHASERS NAMED ON SCHEDULE 2.01 Dated June 1, 2003 TABLE OF CONTENTSSecurities Purchase Agreement • June 2nd, 2003 • Aspen Technology Inc /De/ • Services-computer programming services • Delaware
EXHIBIT 99.4 INVESTOR RIGHTS AGREEMENT BY AND AMONG ASPEN TECHNOLOGY, INC. AND THE STOCKHOLDERS NAMED HEREIN DATED , 2003 TABLE OF CONTENTSInvestor Rights Agreement • June 2nd, 2003 • Aspen Technology Inc /De/ • Services-computer programming services • Delaware
EXHIBIT 99.3Voting Agreement • June 2nd, 2003 • Aspen Technology Inc /De/ • Services-computer programming services • Delaware
Exhibit 99.7 SENIOR SUBORDINATED PROMISSORY NOTESenior Subordinated Promissory Note • June 2nd, 2003 • Aspen Technology Inc /De/ • Services-computer programming services • New York
PAGE ARTICLE I DEFINITIONS; PRINCIPLES OF INTERPRETATION ................ 1 Section 1.01 Definitions ....................................... 1 Section 1.02 Interpretation and Rules of Construction .......... 1 ARTICLE II CLOSING...Repurchase and Exchange Agreement • June 2nd, 2003 • Aspen Technology Inc /De/ • Services-computer programming services • Delaware
