BillionToOne, Inc., a precision diagnostics company, quantifies biology to create molecular diagnostics. The company provides molecular counting platform, which is designed to detect and measure DNA molecules at the single-count level to help enhance disease detection. It also offers UNITY Complete, a non-invasive prenatal screen that assesses fetal risk for aneuploidies, recessive conditions, and fetal antigens from a maternal blood draw; Northstar Select, a liquid biopsy test that provides a list of mutations that are present in the tumor and types of mutations detected that include deletions, insertions, and point mutations; and Northstar Response, a methylation-based assay that quantifies the amount of cancer at the single molecule level without requiring a tissue biopsy, enabling real-time monitoring of patient response to therapy with unprecedented precision. BillionToOne, Inc. was incorporated in 2016 and is headquartered in Menlo Park, California.