# EDGAR Filing Document

**Accession Number:** 0001818331
**File Stem:** 0001689575-26-000003
**Filing Date:** 2026-1
**Character Count:** 8404
**Document Hash:** cef5c5bce8cc01caac54a583f40be4ef
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001689575-26-000003.hdr.sgml**: 20260129

**ACCESSION NUMBER**: 0001689575-26-000003

**CONFORMED SUBMISSION TYPE**: 144

**PUBLIC DOCUMENT COUNT**: 1

**FILED AS OF DATE**: 20260129

**DATE AS OF CHANGE**: 20260129

**SUBJECT COMPANY**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** GeneDx Holdings Corp.
- **CENTRAL INDEX KEY:** 0001818331
- **STANDARD INDUSTRIAL CLASSIFICATION:** SERVICES-HEALTH SERVICES [8000]
- **ORGANIZATION NAME:** 08 Industrial Applications and Services
- **EIN:** 851966622
- **STATE OF INCORPORATION:** DE
- **FISCAL YEAR END:** 1231

**FILING VALUES:**
- **FORM TYPE:** 144
- **SEC ACT:** 1933 Act
- **SEC FILE NUMBER:** 001-39482
- **FILM NUMBER:** 26579879

**BUSINESS ADDRESS:**
- **STREET 1:** 333 LUDLOW STREET
- **STREET 2:** NORTH TOWER, 6TH FLOOR
- **CITY:** STAMFORD
- **STATE:** CT
- **ZIP:** 06902
- **BUSINESS PHONE:** 888-729-1206

**MAIL ADDRESS:**
- **STREET 1:** 333 LUDLOW STREET
- **STREET 2:** NORTH TOWER, 6TH 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
**REPORTING-OWNER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** Stueland Katherine
- **CENTRAL INDEX KEY:** 0001689575

**ORGANIZATION NAME:**

**FILING VALUES:**
- **FORM TYPE:** 144

**MAIL ADDRESS:**
- **STREET 1:** 458 BRANNAN STREET
- **CITY:** SAN FRANCISCO
- **STATE:** CA
- **ZIP:** 94107

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

## FORM 144

### NOTICE OF PROPOSED SALE OF SECURITIES
### PURSUANT TO RULE 144 UNDER THE SECURITIES ACT OF 1933

### 144: Filer Information

**Filer CIK:** 0001689575

**Is this a LIVE or TEST Filing?:** LIVE

### Submission Contact Information
_Not provided in this filing._

### 144: Issuer Information

**Name of Issuer:** GeneDx Holdings Corp.

**SEC File Number:** 001-39482

**Address of Issuer:** 333 Ludlow St, North Tower, Stamford, CT, 06902

**Phone:** 8887291206

**Name of Person for Whose Account the Securities are to Be Sold:** Katherine Stueland

**Relationship to Issuer:** Officer, Director

See the definition of "person" in paragraph (a) of Rule 144.
Information is to be given not only as to the person for whose account
the securities are to be sold but also as to all other persons
included in that definition. In addition, information shall be given
as to sales by all persons whose sales are required by paragraph (e)
of Rule 144 to be aggregated with sales for the account of the person
filing this notice.

### 144: Securities Information

|  |  |  |  |  |  |  |
|:---|:---|:---|:---|:---|:---|:---|
| Title of the Class of Securities To Be Sold | Name and Address of the Broker                                              | Number of Shares or Other Units To Be Sold | Aggregate Market Value | Number of Shares or Other Units Outstanding | Approximate Date of Sale | Name the Securities Exchange |
| Class A Common Stock                        | Morgan Stanley Smith Barney<br>2000 Westchester Avenue<br>Purchase NY 10577 | 94495                                      | 9268700                | 28904590                                    | 01/29/2026               | NASDAQ                       |

Furnish the following information with respect to the acquisition of
the securities to be sold and with respect to the payment of all or
any part of the purchase price or other consideration therefor:

### 144: Securities To Be Sold

|  |  |  |  |  |  |  |  |
|:---|:---|:---|:---|:---|:---|:---|:---|
| Title of the Class   | Date you Acquired | Nature of Acquisition Transaction                                   | Name of Person from Whom Acquired | Is this a Gift? | Amount of Securities Acquired | Date of Payment | Nature of Payment * |
| Class A Common Stock | 05/02/2022        | Acquired as compensation - Restricted Stock Units                   | Issuer                            | No              | 1653                          | 05/02/2022      | Compensation        |
| Class A Common Stock | 03/15/2025        | Acquired as compensation - Performance-based Restricted Stock Units | Issuer                            | No              | 26847                         | 03/15/2025      | Compensation        |
| Class A Common Stock | 12/09/2022        | Acquired as compensation - Restricted Stock Units                   | Issuer                            | No              | 3686                          | 12/09/2022      | Compensation        |
| Class A Common Stock | 03/15/2025        | Acquired as compensation - Restricted Stock Units                   | Issuer                            | No              | 6712                          | 03/15/2025      | Compensation        |
| Class A Common Stock | 04/26/2023        | Acquired as compensation - Restricted Stock Units                   | Issuer                            | No              | 10557                         | 04/26/2023      | Compensation        |
| Class A Common Stock | 03/26/2024        | Acquired as compensation - Restricted Stock Units                   | Issuer                            | No              | 45040                         | 03/26/2024      | Compensation        |

* If the securities were purchased and full payment therefor was not
made in cash at the time of purchase, explain in the table or in a
note thereto the nature of the consideration given. If the
consideration consisted of any note or other obligation, or if payment
was made in installments describe the arrangement and state when the
note or other obligation was discharged in full or the last
installment paid.

Furnish the following information as to all securities of the issuer
sold during the past 3 months by the person for whose account the
securities are to be sold.

### 144: Securities Sold During The Past 3 Months

|  |  |  |  |  |
|:---|:---|:---|:---|:---|
| Name and Address of Seller                                                         | Title of Securities Sold | Date of Sale | Amount of Securities Sold | Gross Proceeds |
| Katherine Stueland<br>333 Ludlow St, North Tower<br>6th Floor<br>Stamford CT 06902 | Class A Common Stock     | 10/29/2025   | 2158                      | 294654         |
| Katherine Stueland<br>333 Ludlow St, North Tower<br>6th Floor<br>Stamford CT 06902 | Class A Common Stock     | 12/09/2025   | 3639                      | 579620         |
| Katherine Stueland<br>333 Ludlow St, North Tower<br>6th Floor<br>Stamford CT 06902 | Class A Common Stock     | 12/16/2025   | 10857                     | 1562217        |

### 144: Remarks and Signature

**Remarks:** Represents approximately 94,495 shares to be sold on behalf of the
Reporting Person, including 1) 1,653 shares to be sold in connection
with vesting of RSUs on January 29, 2026; 2) approximately 26,847
shares to be sold in connection with anticipated vesting of PRSUs on
or around March 3, 2026; 3) approximately 3,686 shares to be sold in
connection with anticipated vesting of RSUs on March 9, 2026; 4)
approximately 6,712 shares to be sold in connection with anticipated
vesting of RSUs on March 15, 2026; 5) approximately 10,557 shares to
be sold in connection with anticipated vesting of RSUs on March 16,
2026; and 6) approximately 45,040 shares to be sold in connection with
anticipated vesting of RSUs on March 26, 2026. Shares sold in the past
3 months by the Reporting Person include 16,654 shares sold to cover
tax withholding obligations in connection with vesting and settlement
of RSUs.

**Date of Notice:** 01/29/2026

ATTENTION:

The person for whose account the securities to which this notice
relates are to be sold hereby represents by signing this notice that
he does not know any material adverse information in regard to the
current and prospective operations of the Issuer of the securities to
be sold which has not been publicly disclosed. If such person has
adopted a written trading plan or given trading instructions to
satisfy Rule 10b5-1 under the Exchange Act, by signing the form and
indicating the date that the plan was adopted or the instruction
given, that person makes such representation as of the plan adoption
or instruction date.

**Signature:** /s/ Katherine Stueland