Bio-Rad makes and sells instruments, reagents, and consumables for life science research and clinical diagnostics, operating through two segments. The Life Science segment (~40% of revenue) sells tools used by researchers to separate, purify, and quantify biological materials like proteins and nucleic acids. The flagship product is Droplet Digital PCR (ddPCR), a technology that precisely quantifies nucleic acids with applications in oncology, cell and gene therapy, and food safety. The Life Science segment also includes process chromatography resins used by biopharma manufacturers to purify therapeutic proteins and vaccines. The Clinical Diagnostics segment (~60% of revenue) sells integrated instrument-and-reagent systems to hospital and commercial labs; key products include quality controls (reagents that verify lab test accuracy), blood typing systems used in transfusion medicine, and diabetes testing. Bio-Rad's business model is built around an installed base: Bio-Rad sells instruments upfront, then generates recurring, higher-margin revenue from proprietary reagents and consumables that customers must continue buying to operate those instruments. In ddPCR, roughly two-thirds of revenue comes from assays and reagents. Bio-Rad sells primarily through a direct sales force globally. Separately, Bio-Rad holds a ~38% voting stake in Sartorius, a German bioprocess equipment company, with a combined fair value of ~$5.7B — well above Bio-Rad's own operating business value. This stake creates large swings in GAAP earnings tied to Sartorius's share price, so analysts focus on non-GAAP results.