Guardant Health is a precision oncology diagnostics company that develops and sells blood-based and tissue-based tests to help oncologists select therapies and monitor cancer patients across the disease continuum. Guardant's flagship product, Guardant360 Liquid, is a comprehensive genomic profiling test run from a blood draw that analyzes cancer-associated genes to identify actionable mutations in advanced solid tumor patients, helping oncologists choose targeted therapies without invasive tissue biopsies. Shield is Guardant's FDA-approved blood test for colorectal cancer screening in average-risk adults, currently reimbursed by Medicare at ~$1,495 per test. Guardant Reveal is a tissue-free blood test for minimal residual disease detection and recurrence monitoring in early-stage cancer patients, and is Guardant's fastest-growing product. Guardant also offers Guardant360 Tissue, a multiomics tissue test. Guardant sells its tests directly to oncologists and primary care physicians through a U.S. sales force and provides testing services to biopharma companies for clinical research and companion diagnostic development. Revenue is driven by test volume and average selling price, which is heavily influenced by Medicare and commercial insurer reimbursement rates. The biopharma segment provides testing services, companion diagnostic development, and data licensing to pharmaceutical companies. Guardant's growth strategy centers on expanding clinical use cases per patient in oncology, scaling Shield's commercial footprint through partnerships with Quest Diagnostics and PathGroup, and expanding Shield toward multi-cancer detection. The core oncology business turned free cash flow positive in the second half of 2025; Guardant targets company-wide free cash flow breakeven by end of 2027.