View:
1 PROSPECTUS SUPPLEMENT NO. 4 FILED PURSUANT TO RULE 424(b)(3) TO PROSPECTUS DATED DECEMBER 10, REGISTRATION NO. 333-63439 $86,250,000 ASPEN TECHNOLOGY, INC. 5 1/4% CONVERTIBLE SUBORDINATED DEBENTURES DUE JUNE 15, 2005 This Prospectus Supplement supplements the information we provided in our December 10, 1998 Prospectus relating to our 5 1/4% Convertible Subordinated Debentures due June 15, 2005 and the shares of our common stock that we must issue upon conversion of those Debentures, and in our Prospectus Supplements No. 1, No. 2 and No. 3. This Prospectus Supplement is not complete without the supplemented Prospectus, and we have not authorized anyone to deliver or use this Prospectus Supplement without the supplemented Prospectus. In this Prospectus Supplement, we use capitalized terms that we defined in the Prospectus. You should read the Prospectus to understand those terms. Unless we indicate otherwise, the information in this Prospectus Supplement is as of April 20, 1999. We are providing this Prospectus Supplement to update the following information to the table in the Prospectus under the caption "Selling Securityholders": - ------------ * Less than one percent. (1) For purposes of this Prospectus Supplement only, we have calculated this percentage on the basis of $86,250,000 aggregate principal amount of Debentures outstanding on April 20, 1999. (2) This Selling Securityholder has indicated that it may offer all of the Debentures that it owns. As a result, no Debentures will be owned after the offering. (3) For purposes of this Prospectus Supplement only, we have calculated this number using the conversion rate described on the front cover page of the Prospectus. (4) For purposes of this Prospectus Supplement only, we have calculated this percentage on the basis of 24,941,642 shares of common stock outstanding on April 20, 1999. THE DATE OF THIS PROSPECTUS SUPPLEMENT IS APRIL 21, 1999.
Principal Amount of Shares of Common Stock Shares of Common Debentures Beneficially Beneficially Owned Stock Beneficially Owned Prior to the Prior to the Shares of Owned After the Offering Amount of Offering Common Offering ---------------------- Debentures ------------------------ Stock ------------------ Selling Securityholder Number Percent(1) Offered(2) Number(3) Percent(4) Offered(3) Number Percent(4) - ---------------------------------------------------------------------------------------------------------------------------- Goldman Sachs & Company $1,587,000 1.8% $1,587,000 29,961 * 29,961 -- --