X0306 4 2021-03-01 0 0001124140 EXACT SCIENCES CORP EXAS 0001689757 Elliott Jeffrey Thomas C/O EXACT SCIENCES CORP. 5505 ENDEAVOR LANE MADISON WI 53719 0 1 0 0 Chief Financial Officer Common Stock 2021-03-01 4 M 0 5025 0.00 A 45223 D Common Stock 2021-03-02 4 S 0 2393 138.42 D 42830 D Common Stock 2021-03-02 4 S 0 1837 140.31 D 40993 D Common Stock 1146 I Held in 401(k) Plan Restricted Stock Units 2021-03-01 4 M 0 5025 0.00 D Common Stock 5025 5025 D Represents shares of common stock received upon vesting of a restricted stock unit award. 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 March 1, 2021. The sale reported in this field was effected pursuant to a Rule 10b5-1 trading plan. In addition to the shares of Common Stock reported on this Form 4, which total 42,139 shares, Mr. Elliott also holds, in the aggregate, an additional 135,562 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. Each restricted stock unit represents a contingent right to receive one share of common stock. Represents a restricted stock unit award granted on February 27, 2018 that partially vested on March 1, 2021. The restricted stock units vest in four equal annual installments beginning on February 27, 2019. /s/ Jeffrey T. Elliott by Mark R. Busch, attorney-in-fact 2021-03-03