SEC Form 4

FORM 4		UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934 or Section 30(h) of the Investment Company Act of 1940	OMB APPROVAL OMB Number: 3235-0287 Estimated average burden hours per response: 0.5
	Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).
	Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan for the purchase or sale of equity securities of the issuer that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.

1. Name and Address of Reporting Person* Casdin Capital, LLC (Last) (First) (Middle) 1350 AVENUE OF THE AMERICAS SUITE 2600 (Street) NEW YORK NEW YORK 10019 (City) (State) (Zip) UNITED STATES (Country)	2. Issuer Name and Ticker or Trading Symbol GeneDx Holdings Corp. [ WGS ]	5. Relationship of Reporting Person(s) to Issuer (Check all applicable) X Director X 10% Owner Officer (give title below) Other (specify below)
	2a. Foreign Trading Symbol
	3. Date of Earliest Transaction (Month/Day/Year) 05/07/2026	6. Individual or Joint/Group Filing (Check Applicable Line) Form filed by One Reporting Person X Form filed by More than One Reporting Person
	4. If Amendment, Date of Original Filed (Month/Day/Year)

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	3. Transaction Code (Instr. 8)		4. Securities Acquired (A) or Disposed Of (D) (Instr. 3, 4 and 5)			5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4)	6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
			Code	V	Amount	(A) or (D)	Price

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	4. Transaction Code (Instr. 8)		5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)		6. Date Exercisable and Expiration Date (Month/Day/Year)		7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4)		8. Price of Derivative Security (Instr. 5)	9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)	10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares
Cash Settled Swap	(1)	05/07/2026		P/K		500,000		(1)	(1)	Class A Common Stock	500,000	(1)	500,000	I	See Footnote(2)
Cash Settled Swap	(3)	05/08/2026		P/K		300,000		(3)	(3)	Class A Common Stock	300,000	(3)	800,000	I	See Footnote(2)
Cash Settled Swap	(4)	05/11/2026		P/K		50,000		(4)	(4)	Class A Common Stock	50,000	(4)	850,000	I	See Footnote(2)

1. Name and Address of Reporting Person* Casdin Capital, LLC (Last) (First) (Middle) 1350 AVENUE OF THE AMERICAS SUITE 2600 (Street) NEW YORK NEW YORK 10019 (City) (State) (Zip) UNITED STATES (Country) Relationship of Reporting Person(s) to Issuer X Director X 10% Owner Officer (give title below) Other (specify below)

1. Name and Address of Reporting Person* Casdin Eli (Last) (First) (Middle) 1350 AVENUE OF THE AMERICAS SUITE 2600 (Street) NEW YORK NEW YORK 10019 (City) (State) (Zip) UNITED STATES (Country) Relationship of Reporting Person(s) to Issuer X Director X 10% Owner Officer (give title below) Other (specify below)

1. Name and Address of Reporting Person* Casdin Partners Master Fund, L.P. (Last) (First) (Middle) 1350 AVENUE OF THE AMERICAS SUITE 2600 (Street) NEW YORK NEW YORK 10019 (City) (State) (Zip) UNITED STATES (Country) Relationship of Reporting Person(s) to Issuer X Director X 10% Owner Officer (give title below) Other (specify below)

1. Name and Address of Reporting Person* Casdin Partners GP, LLC (Last) (First) (Middle) 1350 AVENUE OF THE AMERICAS SUITE 2600 (Street) NEW YORK NEW YORK 10019 (City) (State) (Zip) UNITED STATES (Country) Relationship of Reporting Person(s) to Issuer X Director X 10% Owner Officer (give title below) Other (specify below)

Explanation of Responses:

1. Casdin Partners Master Fund, L.P. (the "Master Fund") has entered into certain cash-settled swap agreements (the "Swap Agreements"), which represent economic exposure to an aggregate of 500,000 notional shares of the Issuer's Class A Common Stock, at a price of $38.1543 per share. The Swap Agreements provide the Master Fund with economic results that are comparable to the economic results of ownership but do not provide it with the power to vote or direct the voting or dispose of or direct the disposition of the securities that are referenced by the Swap Agreements.

2. The Swap Agreements are owned directly by the Master Fund and may be deemed to be indirectly beneficially owned by (i) Casdin Capital, LLC, the investment adviser to the Master Fund ("Casdin"), (ii) Casdin Partners GP, LLC, the general partner of the Master Fund (the "GP"), and (iii) Eli Casdin, the managing member of Casdin and the GP.

3. The Master Fund has entered into certain cash-settled swap agreements (the "Swap Agreements"), which represent economic exposure to an aggregate of 300,000 notional shares of the Issuer's Class A Common Stock, at a price of $41.0261 per share. The Swap Agreements provide the Master Fund with economic results that are comparable to the economic results of ownership but do not provide it with the power to vote or direct the voting or dispose of or direct the disposition of the securities that are referenced by the Swap Agreements.

4. The Master Fund has entered into certain cash-settled swap agreements (the "Swap Agreements"), which represent economic exposure to an aggregate of 50,000 notional shares of the Issuer's Class A Common Stock, at a price of $39.6602 per share. The Swap Agreements provide the Master Fund with economic results that are comparable to the economic results of ownership but do not provide it with the power to vote or direct the voting or dispose of or direct the disposition of the securities that are referenced by the Swap Agreements.

Remarks:

Each Reporting Person disclaims beneficial ownership in the securities reported on this Form 4 except to the extent of its pecuniary interest, if any, therein, and this report shall not be deemed to be an admission that such Reporting Person is the beneficial owner of such securities for purposes of Section 16 or for any other purpose.

	Casdin Capital LLC, By: /s/ Eli Casdin, Managing Member	05/11/2026
	/s/ Eli Casdin, Eli Casdin	05/11/2026
	Casdin Partners Master Fund, LP, By: Casdin Partners GP, LLC, its General Partner, By: /s/ Eli Casdin, Managing Member	05/11/2026
	Casdin Partners GP LLC, By: /s/ Eli Casdin, Managing Member, /s/ Eli Casdin, Eli Casdin	05/11/2026
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 4 (b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.
* Form 4: SEC 1474 (03-26)