X0306 4 2019-02-28 0 0001124140 EXACT SCIENCES CORP EXAS 0001689757 Elliott Jeffrey Thomas C/O EXACT SCIENCES CORP. 441 CHARMANY DRIVE MADISON WI 53719 0 1 0 0 Chief Financial Officer Common Stock 2019-02-28 4 S 0 2447 93.204 D 40644 D Common Stock 960 I Held in 401(K) Plan Represents shares sold pursuant to a Sell-to-Cover Rule 10b5-1 Plan to pay withholding taxes due in connection with the vesting of certain restricted stock units on February 27, 2019. In addition to the shares of Common Stock reported on this Form 4, which total 41,604 shares, Mr. Elliott also holds, in the aggregate, an additional 177,983 vested and unvested options to purchase shares of Common Stock and restricted stock units, with each restricted stock unit representing a contingent right to receive one share of Common Stock. /s/ Jeffrey T. Elliott by Mark R. Busch, attorney-in-fact 2019-03-01