Note 1. Company and Nature of Business

Personalis, Inc. (the "Company" or "Personalis") develops, markets, and sells advanced cancer genomic testing services. The testing services are used by physicians to detect residual or recurrent cancer in patients, monitor cancer response to therapy, and uncover insights for therapy selection. The testing services are also used by pharmaceutical companies for translational research, biomarker discovery, the development of personalized cancer therapies, and clinical trials. The Company also provides whole exome sequencing services for other diagnostic companies and whole genome sequencing services for population sequencing initiatives. The markets for the Company’s testing services are in the United States, Europe and Asia-Pacific.

The Company was incorporated in Delaware in February 2011 and began operations in September 2011. The Company formed a wholly owned subsidiary, Personalis (UK) Ltd., in August 2013. The Company operates and manages its business as one reportable operating segment, which is to provide advanced cancer genomic testing services for precision oncology applications, personalized testing, and other tests.

The Company has incurred losses to date and expects to incur additional losses for the foreseeable future. The Company continues to invest the majority of its resources in the development and growth of its business, including investments in research and development and sales and marketing efforts. The Company’s activities have been financed to date primarily through the sale of its equity securities and cash from operations.

Agreement and Plan of Merger

On July 20, 2026, the Company, Tempus AI, Inc. ("Tempus" or "Parent"), Aviary Development, Inc. (a wholly owned subsidiary of Tempus), and Toucan Development, LLC (a wholly owned subsidiary of Tempus) entered into a Merger Agreement. See Note 13 for further details.