# EDGAR Filing Document

**Accession Number:** 0001534265
**File Stem:** 0000899243-23-004567
**Filing Date:** 2023-2
**Character Count:** 12243
**Document Hash:** 33fe1ea99751699716b8853229d079d5
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0000899243-23-004567.hdr.sgml**: 20230210

**ACCESSION NUMBER**: 0000899243-23-004567

**CONFORMED SUBMISSION TYPE**: 3

**PUBLIC DOCUMENT COUNT**: 2

**CONFORMED PERIOD OF REPORT**: 20230131

**FILED AS OF DATE**: 20230210

**DATE AS OF CHANGE**: 20230210

**REPORTING-OWNER**: 

**OWNER DATA:**
- **COMPANY CONFORMED NAME:** Casdin Partners GP, LLC
- **CENTRAL INDEX KEY:** 0001534260
- **STATE OF INCORPORATION:** DE
- **FISCAL YEAR END:** 1231

**FILING VALUES:**
- **FORM TYPE:** 3
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 001-39482
- **FILM NUMBER:** 23611762

**BUSINESS ADDRESS:**
- **STREET 1:** 1350 AVENUE OF THE AMERICAS
- **STREET 2:** SUITE 1140
- **CITY:** NEW YORK
- **STATE:** NY
- **ZIP:** 10019
- **BUSINESS PHONE:** 212.300.5575

**MAIL ADDRESS:**
- **STREET 1:** 1350 AVENUE OF THE AMERICAS
- **STREET 2:** SUITE 1140
- **CITY:** NEW YORK
- **STATE:** NY
- **ZIP:** 10019
**REPORTING-OWNER**: 

**OWNER DATA:**
- **COMPANY CONFORMED NAME:** Casdin Capital, LLC
- **CENTRAL INDEX KEY:** 0001534261
- **STATE OF INCORPORATION:** DE
- **FISCAL YEAR END:** 1231

**FILING VALUES:**
- **FORM TYPE:** 3
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 001-39482
- **FILM NUMBER:** 23611763

**BUSINESS ADDRESS:**
- **STREET 1:** 1350 AVENUE OF THE AMERICAS
- **STREET 2:** SUITE 2600
- **CITY:** NEW YORK
- **STATE:** NY
- **ZIP:** 10019
- **BUSINESS PHONE:** 212.300.5575

**MAIL ADDRESS:**
- **STREET 1:** 1350 AVENUE OF THE AMERICAS
- **STREET 2:** SUITE 2600
- **CITY:** NEW YORK
- **STATE:** NY
- **ZIP:** 10019
**REPORTING-OWNER**: 

**OWNER DATA:**
- **COMPANY CONFORMED NAME:** Casdin Partners FO1-MSV, LP
- **CENTRAL INDEX KEY:** 0001938709
- **STATE OF INCORPORATION:** DE
- **FISCAL YEAR END:** 1231

**FILING VALUES:**
- **FORM TYPE:** 3
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 001-39482
- **FILM NUMBER:** 23611760

**BUSINESS ADDRESS:**
- **STREET 1:** C/O CASDIN PARTNERS GP, LLC
- **STREET 2:** 1350 AVENUE OF THE AMERICAS, SUITE 2600
- **CITY:** NEW YORK
- **STATE:** NY
- **ZIP:** 10019
- **BUSINESS PHONE:** 212-897-5430

**MAIL ADDRESS:**
- **STREET 1:** C/O CASDIN PARTNERS GP, LLC
- **STREET 2:** 1350 AVENUE OF THE AMERICAS, SUITE 2600
- **CITY:** NEW YORK
- **STATE:** NY
- **ZIP:** 10019
**REPORTING-OWNER**: 

**OWNER DATA:**
- **COMPANY CONFORMED NAME:** Casdin Partners Master Fund, L.P.
- **CENTRAL INDEX KEY:** 0001534265
- **STATE OF INCORPORATION:** E9
- **FISCAL YEAR END:** 1231

**FILING VALUES:**
- **FORM TYPE:** 3
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 001-39482
- **FILM NUMBER:** 23611761

**BUSINESS ADDRESS:**
- **STREET 1:** WALKER HOUSE
- **STREET 2:** 87 MARY STREET
- **CITY:** GEORGE TOWN
- **STATE:** E9
- **ZIP:** KY1-9001
- **BUSINESS PHONE:** 212.300.5575

**MAIL ADDRESS:**
- **STREET 1:** WALKER HOUSE
- **STREET 2:** 87 MARY STREET
- **CITY:** GEORGE TOWN
- **STATE:** E9
- **ZIP:** KY1-9001
**ISSUER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** GeneDx Holdings Corp.
- **CENTRAL INDEX KEY:** 0001818331
- **STANDARD INDUSTRIAL CLASSIFICATION:** SERVICES-HEALTH SERVICES [8000]
- **IRS NUMBER:** 851966622
- **STATE OF INCORPORATION:** DE
- **FISCAL YEAR END:** 1231

**BUSINESS ADDRESS:**
- **STREET 1:** 333 LUDLOW STREET
- **STREET 2:** NORTH TOWER, 8TH FLOOR
- **CITY:** STAMFORD
- **STATE:** CT
- **ZIP:** 06902
- **BUSINESS PHONE:** 617 780 8742

**MAIL ADDRESS:**
- **STREET 1:** 333 LUDLOW STREET
- **STREET 2:** NORTH TOWER, 8TH FLOOR
- **CITY:** STAMFORD
- **STATE:** CT
- **ZIP:** 06902

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** Sema4 Holdings Corp.
- **DATE OF NAME CHANGE:** 20210721

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** CM Life Sciences, Inc.
- **DATE OF NAME CHANGE:** 20200715

## Exhibit 99.1

```
<PRE>
                                                                    Exhibit 99.1

                         Form 3 Joint Filer Information

Name:                                        Casdin Partners GP, LLC

Address:                                     1350 Avenue of the Americas
                                             Suite 2600
                                             New York, NY 10019

Date of Event Requiring Statement:           01/31/2023

Name:                                        Casdin Partners Master Fund, LP

Address:                                     1350 Avenue of the Americas
                                             Suite 2600
                                             New York, NY 10019

Date of Event Requiring Statement:           01/31/2023

Name:                                        Casdin Partners FO1-MSV, LP

Address:                                     1350 Avenue of the Americas
                                             Suite 2600
                                             New York, NY 10019

Date of Event Requiring Statement:           01/31/2023

</PRE>
```

### UNITED STATES SECURITIES AND EXCHANGE COMMISSION
**Washington, D.C. 20549**

## FORM 3

### INITIAL STATEMENT OF BENEFICIAL OWNERSHIP OF SECURITIES

[ ] Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

---

| | | |
|:---|:---|:---|
| **1. Name and Address of Reporting Person**<sup>*</sup><br>Casdin Capital, LLC<br><sub>(Last) (First) (Middle)</sub><br>1350 AVENUE OF THE AMERICAS<br>SUITE 2600<br><sub>(Street)</sub><br>NEW YORK, NY 10019<br><sub>(City) (State) (Zip)</sub> | **3. Issuer Name and Ticker or Trading Symbol**<br>GeneDx Holdings Corp. [ WGS ] | **5. If Amendment, Date of Original Filed (Month/Day/Year)**<br>  |
| **2. Date of Event Requiring Statement (Month/Day/Year)**<br>2023-01-31 | **4. Relationship of Reporting Person(s) to Issuer**<br>(Check all applicable)<br>[X] Director   [X] 10% Owner<br>[ ] Officer (give title below)   [ ] Other (specify below)<br>_ _ | **6. Individual or Joint/Group Filing (Check Applicable Line)**<br>[ ] Form filed by One Reporting Person<br>[X] Form filed by More than One Reporting Person |

---

---

| | | |
|:---|:---|:---|
| **1. Name and Address of Reporting Person**<sup>*</sup><br>Casdin Partners GP, LLC<br><sub>(Last) (First) (Middle)</sub><br>1350 AVENUE OF THE AMERICAS<br>SUITE 2600<br><sub>(Street)</sub><br>NEW YORK, NY 10019<br><sub>(City) (State) (Zip)</sub> | **3. Issuer Name and Ticker or Trading Symbol**<br>GeneDx Holdings Corp. [ WGS ] | **5. If Amendment, Date of Original Filed (Month/Day/Year)**<br>  |
| **2. Date of Event Requiring Statement (Month/Day/Year)**<br>2023-01-31 | **4. Relationship of Reporting Person(s) to Issuer**<br>(Check all applicable)<br>[X] Director   [X] 10% Owner<br>[ ] Officer (give title below)   [ ] Other (specify below)<br>_ _ | **6. Individual or Joint/Group Filing (Check Applicable Line)**<br>[ ] Form filed by One Reporting Person<br>[X] Form filed by More than One Reporting Person |

---

---

| | | |
|:---|:---|:---|
| **1. Name and Address of Reporting Person**<sup>*</sup><br>Casdin Partners Master Fund, L.P.<br><sub>(Last) (First) (Middle)</sub><br>1350 AVENUE OF THE AMERICAS<br>SUITE 2600<br><sub>(Street)</sub><br>NEW YORK, NY 10019<br><sub>(City) (State) (Zip)</sub> | **3. Issuer Name and Ticker or Trading Symbol**<br>GeneDx Holdings Corp. [ WGS ] | **5. If Amendment, Date of Original Filed (Month/Day/Year)**<br>  |
| **2. Date of Event Requiring Statement (Month/Day/Year)**<br>2023-01-31 | **4. Relationship of Reporting Person(s) to Issuer**<br>(Check all applicable)<br>[X] Director   [X] 10% Owner<br>[ ] Officer (give title below)   [ ] Other (specify below)<br>_ _ | **6. Individual or Joint/Group Filing (Check Applicable Line)**<br>[ ] Form filed by One Reporting Person<br>[X] Form filed by More than One Reporting Person |

---

---

| | | |
|:---|:---|:---|
| **1. Name and Address of Reporting Person**<sup>*</sup><br>Casdin Partners FO1-MSV, LP<br><sub>(Last) (First) (Middle)</sub><br>1350 AVENUE OF THE AMERICAS<br>SUITE 2600<br><sub>(Street)</sub><br>NEW YORK, NY 10019<br><sub>(City) (State) (Zip)</sub> | **3. Issuer Name and Ticker or Trading Symbol**<br>GeneDx Holdings Corp. [ WGS ] | **5. If Amendment, Date of Original Filed (Month/Day/Year)**<br>  |
| **2. Date of Event Requiring Statement (Month/Day/Year)**<br>2023-01-31 | **4. Relationship of Reporting Person(s) to Issuer**<br>(Check all applicable)<br>[X] Director   [X] 10% Owner<br>[ ] Officer (give title below)   [ ] Other (specify below)<br>_ _ | **6. Individual or Joint/Group Filing (Check Applicable Line)**<br>[ ] Form filed by One Reporting Person<br>[X] Form filed by More than One Reporting Person |

---

## Table I - Non-Derivative Securities Beneficially Owned

---

|  |  |  |  |
| --- | --- | --- | --- |
| 1. Title of Security | 2. Amount of Securities Beneficially Owned | 3. Ownership Form | 4. Nature of Indirect Beneficial Ownership |
| Class A Common Stock | 87866042 | I | See Footnote<sup>(1)</sup> |
| Class A Common Stock | 14285743 | I | See Footnote<sup>(2)</sup> |

---

## Table II - Derivative Securities Beneficially Owned

---

|  |  |  |  |  |  |  |  |
| --- | --- | --- | --- | --- | --- | --- | --- |
| 1. Title of Derivative Security | 2. Date Exercisable and Expiration Date (Month/Day/Year) | 2. Date Exercisable and Expiration Date (Month/Day/Year) | 3. Title and Amount of Underlying Securities | 3. Title and Amount of Underlying Securities | 4. Conversion or Exercise Price | 5. Ownership Form | 6. Nature of Indirect Beneficial Ownership |
| 1. Title of Derivative Security | Date Exercisable | Expiration Date | Title | Amount or Number of Shares | 4. Conversion or Exercise Price | 5. Ownership Form | 6. Nature of Indirect Beneficial Ownership |
|  |  |  |  |  |  |  |  |

---

### Footnotes:

(1) The 87,866,042 shares of Class A common stock reported in the table above are owned directly by Casdin Partners Master Fund, LP and may be deemed to be indirectly beneficially owned by (i) Casdin Capital, LLC, the investment adviser to Casdin Partners Master Fund, LP, (ii) Casdin Partners GP, LLC, the general partner of Casdin Partners Master Fund LP, and (iii) Mr. Casdin, the managing member of Casdin Capital, LLC and Casdin Partners GP, LLC. Each of Casdin Capital, LLC, Casdin Partners GP, LLC and Mr. Casdin disclaims beneficial ownership of such securities except to the extent of its or his respective pecuniary interest therein.

(2) The 14,285,743 shares of Class A common stock reported in the table above are owned directly by Casdin Partners FO1-MSV, LP and may be deemed to be indirectly beneficially owned by (i) Casdin Capital, LLC, the investment adviser to Casdin Partners FO1-MSV, LP, (ii) Casdin Partners GP, LLC, the general partner of Casdin Partners FO1-MSV, LP, and (iii) Mr. Casdin, the managing member of Casdin Capital, LLC and Casdin Partners GP, LLC. Each of Casdin Capital, LLC, Casdin Partners GP, LLC and Mr. Casdin disclaims beneficial ownership of such securities except to the extent of its or his respective pecuniary interest therein.

**Signature:** CASDIN CAPITAL, LLC, Name: /s/ Eli Casdin, Title: Managing Member  
**Date:** 2023-02-10

**Signature:** CASDIN PARTNERS GP, LLC, Name: /s/ Eli Casdin, Title: Managing Member  
**Date:** 2023-02-10

**Signature:** CASDIN PARTNERS MASTER FUND, LP, By: Casdin Partners GP, LLC, Its: General Partner, Name: /s/ Eli Casdin, Title: Managing Member  
**Date:** 2023-02-10

**Signature:** CASDIN PARTNERS FO1-MSV, LP, By: Casdin Partners GP, LLC, Its: General Partner, Name: /s/ Eli Casdin, Title: Managing Member  
**Date:** 2023-02-10

### Remarks:

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.**