X0306 4 2017-05-16 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 2017-05-16 4 F 0 2246 21.75 D 42245 D Common Stock 2017-05-17 4 A 0 8750 0.00 A 50995 D Common Stock 2017-05-17 4 A 0 2917 0.00 A 53912 D These shares were withheld by the Company to cover the tax withholding obligations of the executive on the vesting of restricted stock units on May 16, 2017. Represents the closing price on May 16, 2017. Of the shares held as of May 16, 2017, 14,319 were issuable on vesting of restricted stock units granted to the executive under the 2012 Equity Incentive Plan and are subject to forfeiture. These shares are issuable on vesting of restricted stock units granted under the Company's 2012 Equity Incentive Plan. Assuming continuation of employment, 25% of these restricted stock units will vest on May 17, 2018, May 17, 2019, May 17, 2020 and May 17, 2021. The executive has agreed that a number of shares, having a value equal to the required tax withholding at vesting, will be withheld from the shares issued on each vest date. These shares are issuable on vesting of restricted stock units granted under the Company's 2012 Equity Incentive Plan. Assuming continuation of employment, some or all of these restricted stock units will vest on February 28, 2018 based on performance vesting criteria. Unvested restricted stock units will forfeit on that date. The executive has agreed that a number of shares, having a value equal to the required tax withholding at vesting, will be withheld from the shares issued on the vest date. Of the shares held as of May 17, 2017, 25,986 were issuable on vesting of restricted stock units granted to the executive under the 2012 Equity Incentive Plan and are subject to forfeiture. Lynnette C. Fallon 2017-05-17