X0306 4 2019-05-01 0000929940 ASPEN TECHNOLOGY INC /DE/ AZPN 0001286687 GANN SIMON OREBI C/O ASPEN TECHNOLOGY, INC. 20 CROSBY DRIVE BEDFORD MA 01730 1 Common Stock 2019-05-01 4 M 0 9500 15.37 A 28645 D Common Stock 2019-05-01 4 S 0 9500 121.21 D 19145 D Director Stock Option (Right to Buy) 15.37 2019-05-01 4 M 0 9500 0 D 2011-06-30 2021-02-14 Common Stock 9500 14500 D The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $120.805 to $121.76, inclusive. The reporting person undertakes to provide to Aspen Technology, Inc., any security holder of Aspen Technology, Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote. The option granted at the exercise price of $15.37 vests in 12 equal consecutive quarterly installments on the last business day of each quarter, beginning June 30, 2011. /s/ F.G. Hammond, attorney-in-fact for Dr. Orebi Gann 2019-05-03