X0306 4/A 2022-05-02 2022-05-04 0 0001818331 Sema4 Holdings Corp. SMFR 0001753655 Leproust Emily M. C/O SEMA4 HOLDINGS CORP. 333 LUDLOW STREET, NORTH TOWER, 8TH FL. STAMFORD CT 06902 1 0 0 0 Stock Option 2.20 2022-05-02 4 A 0 78914 0.00 A 2032-05-01 Class A Common Stock 78914 78914 D This Form 4 amendment has been filed solely to correct the exercise price of a previously issued stock option to purchase shares of Class A Common Stock of the Issuer reported in a Form 4 filed on May 4, 2022 (the "Form 4"). The exercise price was inadvertently stated as $2.155 in the Form 4. The exercise price should have been stated as $2.20 in the Form 4. The underlying shares shall vest the earlier of (a) the date of the next annual meeting of the Issuer's shareholders following the grant date, and (b) the first anniversary of the grant date, subject to the Reporting Person continuing to provide services to the Issuer through each vesting date. /s/ Daniel Clark, Attorney-in-Fact 2022-05-06