X0306 4 2017-05-12 0 0001113232 AXCELIS TECHNOLOGIES INC ACLS 0001195654 FALLON LYNNETTE C C/O AXCELIS TECHNOLOGIES, INC. 108 CHERRY HILL DRIVE BEVERLY MA 01915 0 1 0 0 Executive VP, HR/Legal Common Stock 2017-05-12 4 M 0 5071 4.64 A 49562 D Common Stock 2017-05-12 4 S 0 5071 21.52 D 44491 D Common Stock 2017-05-15 4 M 0 26179 4.64 A 70670 D Common Stock 2017-05-15 4 S 0 26179 21.16 D 44491 D Stock option (right to buy) 4.64 2017-05-12 4 M 0 5071 0.00 D 2013-11-16 2019-11-16 Common Stock 5071 26179 D Stock option (right to buy) 4.64 2017-05-15 4 M 0 26179 0.00 D 2013-11-16 2019-11-16 Common Stock 26179 0 D The price reported in Column 4 is a weighted-average price. These shares were sold in multiple transactions at prices ranging from $21.50 to $21.55, inclusive. The reporting person undertakes to provide to Axcelis Technologies, Inc., any security holder of Axcelis Technologies, Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares purchased at each separate price. Of the shares held as of May 12 and 15, 2017, 19,091 were issuable on vesting of restricted stock units granted under the 2012 Equity Incentive Plan and are subject to forfeiture. The price reported in Column 4 is a weighted-average price. These shares were sold in multiple transactions at prices ranging from $21.15 to $21.25, inclusive. The reporting person undertakes to provide to Axcelis Technologies, Inc., any security holder of Axcelis Technologies, Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares purchased at each separate price. Lynnette C. Fallon 2017-05-15