GeneDx Holdings Corp.

Rule 10b5-1 Plan Adoptions and Modifications

On August 27, 2025, a grantor annuity trust (the “GRAT”) of which Jason Ryan, ourchairman and a director, is the trustee, terminated a written plan for the potential transfer of up to an aggregate of 141,356 shares of our Class A common stock that had previously been entered into on November 7, 2024 (the “Ryan GRAT 10b5-1 Plan”). The Ryan GRAT 10b5-1 Plan was intended to satisfy the affirmative defense conditions of Rule 10b5-1(c) under the Exchange Act and had provided that it would be effective until March 5, 2027.

On September 11, 2025, Katherine Stueland, our Chief Executive Officer, entered into a written plan for the potential sale of up to an aggregate of 40,000 shares of our Class A common stock, including shares underlying Ms. Stueland’s restricted stock unit (“RSU”) awards (the “Stueland 10b5-1 Plan”). The Stueland 10b5-1 Plan is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c) under the Exchange Act and will be effective from April 10, 2026 to October 30, 2026.

On September 15, 2025, Bryan Dechairo, our Chief Operating Officer, entered into a written plan for the potential sale of up to an aggregate of 9,374 shares of our Class A common stock, including shares underlying Mr. Dechairo’s RSU awards (the “Dechairo 10b5-1 Plan” and, together with the Stueland 10b5-1 Plan, the “10b5-1 Plans”). The Dechairo 10b5-1 Plan is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c) under the Exchange Act and will be effective from February 4, 2026 to September 30, 2026.

Each 10b5-1 Plan included a representation from the applicable officer to the broker administering the 10b5-1 Plan that the officer was not in possession of any material nonpublic information regarding the Company or the securities subject to the 10b5-1 Plan. A similar representation was made to us in a certification from each officer provided to us in connection with the adoption of the applicable 10b5-1 Plan under our insider trading policy. Those representations were made as of the date of adoption of the applicable 10b5-1 Plan or the certification, as applicable, and speak only as of those dates. In making those representations, there is no assurance with respect to any material non-public information of which the officer was unaware, or with respect to any material non-public information acquired by the officer or us after the applicable date of the representation.

Other than as disclosed above, during the quarter ended September 30, 2025, none of our directors or officers adopted orterminated any “Rule 10b5-1 trading arrangements” or any “non-Rule 10b5-1 trading arrangements,” as each term is defined in Item 408 of Regulation S-K.

Supplemental Disclosure to our Annual Report on Form 10-K for the year ended December 31, 2024

The following updates Part I, Item 1. “Business—Intellectual Property—Patents”in our 2024 Form 10-K:

Patents

The fields of genomic and health information analysis present limited opportunities for patent protection, based on current legal precedents. Our patent protection strategy has focused on seeking protection for certain of our non-gene specific technology and our specific biomarkers. In this regard, we have one issued U.S. design patent, fourteen pending U.S. non-provisional utility patent applications, seven pending U.S. provisional patent applications, and three pending international PCT patent applications. The issued U.S. design patent relates to a display screen with a graphical user interface. The utility patent applications include an international PCT patent application and a U.S. patent application related to performing phenotypic fit analysis, an international PCT patent application and two U.S. patent applications related to analyzing genetic variations and phenotypes, a U.S. patent application related to modeling inference of mutation impact, two U.S. patent applications related to generating a cancer determination from electronic health records using a cancer determination analysis system, a U.S. patent application related to providing a homologous recombination DNA repair deficiency score for a cancer patient, a U.S. patent application related to therapeutic treatment for subjects having certain polymorphic markers associated with specific human leukocyte antigen alleles, two U.S. patent applications relating to analyzing phenotype-causing genomic variants, two U.S. patent applications relating to prioritizing phenotype-causing genomic variants in combination with biomedical ontologies, two U.S. patent applications relating to prioritizing phenotype-causing genomic variants in combination with clinical information, and an international PCT patent application relating to analyzing long biological sequence data. If patents are issued from the currently pending applications, the earliest patents will begin expiring in the early 2030s, subject to potential extensions of the patent term that will be calculated based on the length of the patent examination process. The claim scope of any potentially issued patents stemming from the present applications may be narrower than included in the initial filings due to any amendments that may arise throughout their prosecution.

We do not presently have any patents directed to the sequences of specific genes or variants of such genes, nor do we currently rely on any in-licensed gene patent rights of any third party. We may, in time, seek additional patent protection to protect technology that is not gene-specific and that provides us with a potential competitive advantage as we focus on making comprehensive genetic information less expensive and more broadly available to our customers.

The following updates Part I, Item 1.“Business—Government Regulation—Diagnostic Products and FDA Oversight of Laboratory Developed Tests” in our 2024 Form 10-K:

FDA Oversight of Laboratory Developed Tests

We currently offer an LDT version of certain tests. Historically, the FDA has exercised a policy of enforcement discretion with respect to most LDTs, whereby the FDA did not actively enforce its medical device regulatory requirements for such tests. However, at various points in recent years, the FDA has indicated that it intends to end enforcement discretion for many tests offered as LDTs, and to require such tests to comply with certain FDA regulatory requirements. Agency officials have previously expressed significant concerns regarding performance disparities between some LDTs and in vitro diagnostics that have been reviewed, cleared, authorized or approved by the FDA.

On April 29, 2024, the FDA published a final rule on LDTs, in which the FDA outlined its plans to end enforcement discretion for many LDTs in five stages over a four-year period.

In response, multiple lawsuits were filed challenging the FDA’s authority to regulate LDTs as medical devices under the Federal Food, Drug, and Cosmetic Act (FDCA). On March 31, 2025, the U.S. District Court for the Eastern District of Texas struck down the 2024 final rule on the grounds that the FDA exceeded its authority under the FDCA. The FDA did not appeal the court’s ruling. As a result, clinical laboratories offering LDTs are not required to comply with any of the phases of the final rule.

Legislative proposals addressing the FDA’s oversight of LDTs have also been introduced in previous Congresses, and we expect that new legislative proposals will be introduced from time-to-time. For example, versions of the Verifying Accurate Leading-edge IVCT Development Act (the “VALID Act”) have been introduced in Congress several times in recent years, but the VALID Act has not been enacted. The VALID Act, as most recently proposed, would create a new category of medical products separate from medical devices called “in vitro clinical tests,” or IVCTs. As most recently proposed, the VALID Act would modify the FDCA and establish a risk-based approach to imposing requirements related to premarket review, quality systems, and labeling requirements on all IVCTs, including LDTs, but a grandfathering provision would create exemptions from certain requirements for certain LDTs (e.g., LDTs first offered for clinical use not later than May 6, 2024). The likelihood that Congress will pass such legislation is difficult to predict at this time.

If the FDA ultimately regulates certain LDTs, our tests may be subject to certain additional regulatory requirements. Complying with the FDA’s requirements can be expensive, time-consuming, and subject us to significant or unanticipated delays. Insofar as we may be required to obtain premarket clearance or approval to perform or continue performing an LDT, we cannot be sure that we will be able to obtain such authorization. Even if we obtain regulatory clearance or approval where required, such authorization may not be for the intended uses that we believe are commercially attractive or are critical to the commercial success of our tests. As a result, the application of the FDA’s oversight to our tests could materially and adversely affect our business, financial condition, and results of operations.

We will continue to monitor changes to all LDT regulatory policy so as to ensure compliance with the current regulatory scheme. The FDA in the course of enforcing the FDCA may subject a company to various sanctions for violating FDA regulations or provisions of the FDCA, including requiring recalls, issuing Warning Letters, seeking to impose civil money penalties, seizing devices that the agency believes are non-compliant, seeking to enjoin distribution of a specific device, seeking to revoke a clearance or approval, seeking disgorgement of profits and/or seeking to criminally prosecute a company and its officers and other responsible parties.

Additionally, certain of our diagnostic products in development may be subject to regulation by the FDA and similar international health authorities. For these products, we would have an obligation to comply with applicable premarket review requirements, and adhere to the FDA’s current Good Manufacturing Practices and diagnostic product regulations, including providing for an establishment and product listing with the FDA. Additionally, we would be subject to periodic FDA inspections, quality control procedures, and other detailed validation procedures. If the FDA finds deficiencies in the validation of our manufacturing and/or our quality control practices, it may impose restrictions on marketing specific products until corrected. Regulation by governmental authorities in the United States and other countries may be a significant factor in how we develop, test, produce and market our diagnostic test products.

In October 2025, the FDA granted Breakthrough Device Designation from the FDA for the Breakthrough Device Designation Indications using our ExomeDx TM and GenomeDx TM tests. We believe this designation highlights the tests’ potential to identify the causes of life-threatening diseases or genetic disorders to aid in the diagnosis of symptomatic patients. The Breakthrough Devices Program is a voluntary program intended to give patients more timely access to medical devices that provide for more effective diagnosis or treatment of life-threatening or irreversibly debilitating diseases by expediting their development, assessment, and review. We expect these designations to help us accelerate the future review and potential authorization of our exome and genomes tests.

The following updates Part I, Item 1.“Business—Government Regulation—Corporate Practice of Medicine” in our 2024 Form 10-K:

Corporate Practice of Medicine

Numerous states prohibit business organizations from practicing medicine or employing or engaging physicians to practice medicine, which prohibitions are generally referred to as the prohibition against the corporate practice of medicine. These laws are intended to prevent interference in the medical decision-making process by anyone who is not a licensed physician. For example, California law establishes that determining what diagnostic tests are appropriate for a particular condition and taking responsibility for the ultimate overall care of the patient, including providing treatment options available to the patient, would constitute the unlicensed practice of medicine if performed by an unlicensed person. Violation of these corporate practice of medicine prohibitions may result in civil or criminal fines, as well as sanctions imposed against us and/or the professional through licensure proceedings.

The following updates Part I, Item 1.“Business—Government Regulation—Other Data Protection Laws” in our 2024 Form 10-K:

Other Data Protection Laws

There are a growing number of jurisdictions around the globe that have privacy and data protection laws that may apply to us as we enter or expand our business in jurisdictions outside of the United States. These laws are typically triggered by a company’s establishment or physical location in the jurisdiction, data processing activities that take place in the jurisdiction, and/or the processing of personal information about individuals located in that jurisdiction that are targeted, for example, by an offer of goods or services or by monitoring their activities. Certain data protection laws, such as those in the European Union, (the “EU”) and United Kingdom (the “UK”), are comprehensive in nature and include significant requirements around the processing of personal information, while other jurisdictions may have no privacy and data protection laws or privacy and data protection laws less restrictive or prescriptive than those in the United States. Enforcement of these laws varies from jurisdiction to jurisdiction, with a variety of consequences, including civil or criminal penalties or the loss of a license to operate in the jurisdiction, individual litigation rights, or damage to our reputation.

For example, the EU’s General Data Protection Regulation (“GDPR”), including as implemented and amended through the UK Data Protection Act 2018 (“UK GDPR”), applies to any data collection, use and sharing in the context of an establishment in the EU or UK as well as extraterritorially to any entity outside the EU and UK when they process personal information related to an offer of goods or services to, or monitoring the behavior of, individuals who are located in the EU or UK, respectively. The GDPR and UK GDPR impose requirements on controllers and processors of personal data, including when personal information is transferred outside of the EU or the UK to another country and enhanced protections for “special categories” of personal data, which include sensitive information such as health and genetic information of data subjects. The GDPR and UK GDPR also grant individuals various rights in relation to their personal data including the rights of access, rectification, objection to certain processing and deletion. The GDPR and UK GDPR provide individuals with an express right to seek legal remedies if the individual believes his or her rights have been violated. Failure to comply with the requirements of the GDPR or the related national data protection laws of the member states of the EU, which may deviate from or be more restrictive than the GDPR, or a failure to comply with the UK GDPR may also result in significant administrative fines and restrictions on our business operations issued by EU or UK regulators.

Recent Accounting Pronouncements

Additional information on recent accounting pronouncements can be found in Note 2, “Summary of Significant Accounting Policies” to our consolidated financial statements included within our 2024 Form 10-K, and Note 2, “Summary of Significant Accounting Policies” to our condensed consolidated financial statements included in this Quarterly Report.