X0407 4 2023-05-02 0 0001818331 GeneDx Holdings Corp. WGS 0001307631 Meister Keith A. C/O CORVEX MANAGEMENT LP 667 MADISON AVENUE NEW YORK NY 10065 1 0 1 0 0 Class A Common Stock 2023-05-02 4 M 0 45454 0.00 A 45454 D Class A Common Stock 120141890 I See footnotes Restricted Stock Unit 2023-05-02 4 M 0 45454 0.00 D Class A Common Stock 45454 0 D 109,148,140 shares of Class A Common Stock of the Issuer are held for the accounts of the Corvex Funds for which Corvex Management LP ("Corvex") acts as investment adviser. The general partner of Corvex is controlled by Mr. Meister. CMLS Holdings LLC ("CMLS Holdings") is the record holder of 10,993,750 shares of the Class A Common Stock reported herein. Mr. Meister is one of two members of the Board of Managers of CMLS Holdings, and Mr. Meister shares voting and investment discretion with respect to the securities held by CMLS Holdings Stock reported herein. Corvex is not an investment adviser to CMLS Holdings. Each restricted stock unit represents a contingent right to receive 1 share of the Issuer's Class A Common Stock upon settlement for no consideration. The underlying shares shall vest on the earlier of the (a) date of the 2023 annual meeting of the Issuer's stockholders, and (b) first anniversary of the grant date, subject to the Reporting Person continuing to provide services to the Issuer on the applicable vesting date. For avoidance of doubt, all numbers above are presented before giving effect to the 33:1 reverse stock split the Issuer's stockholders approved on April 14, 2023, which was previously disclosed in the Current Reports on Form 8-K filed by the Issuer on April 17, 2023 and April 28, 2023, and which shall become effective on May 4, 2023. /s/ Eunkyung Lee, Attorney-in-Fact 2023-05-04