STOCK TITAN

Casdin-linked funds add 500K GeneDx (WGS) shares in open-market buys

Filing Impact
(Very High)
Filing Sentiment
(Very Positive)
Form Type
4

Rhea-AI Filing Summary

GeneDx Holdings Corp. reported that investment entities associated with Casdin Capital made open-market purchases of a total of 500,000 shares of Class A Common Stock. These buys occurred on May 18–20, 2026 at weighted average prices in the low-to-mid $40 range.

After these transactions, an investment fund managed by Casdin Capital reported holding 3,507,164 shares indirectly. Separate positions include 20,517 shares owned directly by Eli Casdin and other indirect holdings of 333,144 and 19,247 shares reported for related entities.

Positive

  • None.

Negative

  • None.
Insider Casdin Capital, LLC, Casdin Eli, Casdin Partners Master Fund, L.P., Casdin Partners GP, LLC
Role null | null | null | null
Bought 500,000 shs ($21.46M)
Type Security Shares Price Value
Purchase Class A Common Stock, par value $0.0001 per share 140,000 $43.8061 $6.13M
Purchase Class A Common Stock, par value $0.0001 per share 185,000 $42.5964 $7.88M
Purchase Class A Common Stock, par value $0.0001 per share 175,000 $42.5517 $7.45M
holding Class A Common Stock, par value $0.0001 per share -- -- --
holding Class A Common Stock, par value $0.0001 per share -- -- --
holding Class A Common Stock, par value $0.0001 per share -- -- --
Holdings After Transaction: Class A Common Stock, par value $0.0001 per share — 3,507,164 shares (Indirect, See footnote); Class A Common Stock, par value $0.0001 per share — 20,517 shares (Direct, null)
Footnotes (1)
  1. The price reported in Column 4 is a weighted average price. These shares were bought in multiple transactions within the range of $42.4573 to $42.9153. The Reporting Persons undertake to provide to the Issuer, any security holder of the Issuer or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares bought at each separate price within the range set forth in this footnote. The securities are owned directly by the Casdin Partners Master Fund, L.P. (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. The price reported in Column 4 is a weighted average price. These shares were bought in multiple transactions within the range of $42.1118 to $42.6898. The Reporting Persons undertake to provide to the Issuer, any security holder of the Issuer or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares bought at each separate price within the range set forth in this footnote. The price reported in Column 4 is a weighted average price. These shares were bought in multiple transactions within the range of $43.6287 to $44.3384. The Reporting Persons undertake to provide to the Issuer, any security holder of the Issuer or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares bought at each separate price within the range set forth in this footnote. The securities are owned directly by Eli Casdin. The securities are owned directly by the GP and may be deemed to be indirectly beneficially owned by Eli Casdin, the managing member of the GP. The securities are owned directly by CMLS Holdings LLC ("CMLS Holdings"). The Board of Managers of CMLS Holdings includes Eli Casdin, who, as a member of the Board of Managers of CMLS Holdings, shares voting and investment discretion with respect to the common stock held by CMLS Holdings.
Open-market purchase 1 175,000 shares at $42.5517 Class A Common Stock bought on May 18, 2026
Open-market purchase 2 185,000 shares at $42.5964 Class A Common Stock bought on May 19, 2026
Open-market purchase 3 140,000 shares at $43.8061 Class A Common Stock bought on May 20, 2026
Total shares bought 500,000 shares Net open-market purchases May 18–20, 2026
Indirect fund holdings 3,507,164 shares Class A Common Stock held indirectly after May 20, 2026
Direct Eli Casdin holdings 20,517 shares Class A Common Stock owned directly as referenced in footnote
Other indirect holdings 333,144 shares Indirect Class A Common Stock position as of May 18, 2026
Additional indirect holdings 19,247 shares Indirect Class A Common Stock position as of May 18, 2026
open-market purchase financial
"transaction_action": "open-market purchase""
An open-market purchase is when an investor or a company buys shares on a public stock exchange at the going market price, rather than through a private deal. It matters to investors because these purchases change how many shares are available, can push the stock price up or signal confidence from large buyers, and often affect per-share metrics like earnings—think of it like someone buying lots of apples off a grocery shelf, reducing supply and potentially raising the price.
weighted average price financial
"The price reported in Column 4 is a weighted average price."
Weighted average price is the average price of a security where each trade or component is counted according to its size, so bigger trades pull the average more than smaller ones. Think of it like calculating the average cost of a grocery haul where items you bought more of have greater influence on the final per-item cost. Investors use it to understand the true average price paid or received, judge execution quality, and compare trading performance against market movement.
indirectly beneficially owned financial
"may be deemed to be indirectly beneficially owned by (i) Casdin Capital, LLC"
Class A Common Stock financial
"Class A Common Stock, par value $0.0001 per share"
Class A common stock is a category of a company’s shares that carries a specific set of ownership rights—most commonly defined voting power and claims on dividends—set out in the company’s charter. For investors it matters because the class determines how much influence you have over corporate decisions, the share’s likely dividend and trading behavior, and how it compares in value to other share classes, like choosing a particular seat with different privileges at the company’s decision-making table.
ten percent owner financial
""is_ten_percent_owner": 1"
investment adviser financial
"Casdin Capital, LLC, the investment adviser to the Master Fund"
An investment adviser is a person or firm that professionally manages money and gives recommendations about buying, selling, or holding investments. Like a financial coach or guide, they have a legal duty to act in a client's best financial interest, so their advice, fees and potential conflicts can directly affect returns and risk — making their role important for investors who want informed, accountable help with portfolios.
SEC Form 4
FORM 4UNITED 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)
XDirectorX10% Owner
Officer (give title below)Other (specify below)
2a. Foreign Trading Symbol
3. Date of Earliest Transaction (Month/Day/Year)
05/18/2026
6. Individual or Joint/Group Filing (Check Applicable Line)
Form filed by One Reporting Person
XForm 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)
CodeVAmount(A) or (D)Price
Class A Common Stock, par value $0.0001 per share05/18/2026P175,000A$42.5517(1)3,182,164ISee footnote(2)
Class A Common Stock, par value $0.0001 per share05/19/2026P185,000A$42.5964(3)3,367,164ISee footnote(2)
Class A Common Stock, par value $0.0001 per share05/20/2026P140,000A$43.8061(4)3,507,164ISee footnote(2)
Class A Common Stock, par value $0.0001 per share20,517D(5)
Class A Common Stock, par value $0.0001 per share19,247ISee foonote(6)
Class A Common Stock, par value $0.0001 per share333,144ISee foonote(7)
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)
CodeV(A)(D)Date ExercisableExpiration DateTitleAmount or Number of Shares
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
XDirectorX10% 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
XDirectorX10% 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
XDirectorX10% 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
XDirectorX10% Owner
Officer (give title below)Other (specify below)
Explanation of Responses:
1. The price reported in Column 4 is a weighted average price. These shares were bought in multiple transactions within the range of $42.4573 to $42.9153. The Reporting Persons undertake to provide to the Issuer, any security holder of the Issuer or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares bought at each separate price within the range set forth in this footnote.
2. The securities are owned directly by the Casdin Partners Master Fund, L.P. (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 price reported in Column 4 is a weighted average price. These shares were bought in multiple transactions within the range of $42.1118 to $42.6898. The Reporting Persons undertake to provide to the Issuer, any security holder of the Issuer or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares bought at each separate price within the range set forth in this footnote.
4. The price reported in Column 4 is a weighted average price. These shares were bought in multiple transactions within the range of $43.6287 to $44.3384. The Reporting Persons undertake to provide to the Issuer, any security holder of the Issuer or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares bought at each separate price within the range set forth in this footnote.
5. The securities are owned directly by Eli Casdin.
6. The securities are owned directly by the GP and may be deemed to be indirectly beneficially owned by Eli Casdin, the managing member of the GP.
7. The securities are owned directly by CMLS Holdings LLC ("CMLS Holdings"). The Board of Managers of CMLS Holdings includes Eli Casdin, who, as a member of the Board of Managers of CMLS Holdings, shares voting and investment discretion with respect to the common stock held by CMLS Holdings.
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 Partners Master Fund, LP, By: Casdin Partners GP, LLC, its General Partner, By: /s/ Eli Casdin, Managing Member05/20/2026
Casdin Capital LLC, By: /s/ Eli Casdin, Managing Member05/20/2026
Casdin Partners GP LLC, By: /s/ Eli Casdin, Managing Member, /s/ Eli Casdin05/20/2026
/s/ Eli Casdin05/20/2026
** Signature of Reporting PersonDate
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)

FAQ

What insider transactions did Casdin Capital report for GeneDx Holdings (WGS)?

Investment entities associated with Casdin Capital reported open-market purchases of 500,000 GeneDx Holdings Class A shares on May 18–20, 2026. These transactions were reported as weighted-average price buys in the low-to-mid $40 range, increasing the fund’s indirect ownership stake.

What is the indirect GeneDx (WGS) stake held by the Casdin-managed fund after these trades?

Following the reported open-market purchases, an investment fund managed by Casdin Capital reported indirectly holding 3,507,164 GeneDx Class A shares. This indirect ownership reflects the fund’s position after the May 18–20, 2026 transactions disclosed in the Form 4 filing.

Does Eli Casdin personally own GeneDx Holdings (WGS) shares in addition to fund holdings?

Yes. The filing states that certain securities are owned directly by Eli Casdin, including 20,517 GeneDx Class A shares. Additional shares are held by related entities where he may share voting or investment discretion, as described in the footnotes.

Which entities associated with Casdin hold GeneDx (WGS) shares according to the filing?

The filing notes holdings by Casdin Partners Master Fund, L.P., Casdin Capital, LLC, Casdin Partners GP, LLC, Eli Casdin personally, and CMLS Holdings LLC. Some entities directly own shares, while others are described as advisers or general partners with indirect beneficial ownership.

Were the reported GeneDx (WGS) insider purchases made in the open market?

Yes. The transactions are coded as “P” and described as open-market or private purchases. Footnotes clarify that reported prices are weighted averages and that individual trades occurred within specified price ranges for each trading day.