Biocept, Inc., established in 1997 and based in San Diego, California, was a molecular oncology diagnostics firm. Its primary business involved the development and commercialization of exclusive clinical laboratory assays within the United States. These advanced tests were engineered to detect elusive tumor cells and cell-free tumor DNA (ctDNA) from both blood and cerebrospinal fluid (CSF) samples. The insights provided by Biocept's cancer assays were instrumental for healthcare professionals, allowing them to pinpoint specific cancer-causing genetic mutations. This capability helped identify suitable cancer patients for targeted therapies, whether at the point of initial diagnosis, during disease progression, or for continuous monitoring to uncover resistance mechanisms. The company offered diagnostic solutions for a variety of solid tumor cancers, such as breast, non-small cell lung (NSCLC), gastric, colorectal, prostate, pancreaticobiliary, and ovarian cancers. Furthermore, Biocept extended specialized testing services for CSF tumor cells, ctDNA, and ctRNA to a diverse group of medical specialists, including medical oncologists, neuro-oncologists, surgical oncologists, radiation oncologists, urologists, pulmonologists, and pathologists. It also supplied clinical trial and research assistance to pharmaceutical and biopharmaceutical companies, along with clinical research organizations. Biocept participated in collaborations, notably with CLEARED4 to create a system for overseeing COVID-19 testing requirements and results for its clientele. Another partnership with Protean BioDiagnostics, Inc. aimed to evaluate the proficiency of its Target Selector molecular assay in ascertaining EGFR status in NSCLC patients. However, Biocept, Inc. voluntarily initiated liquidation proceedings by filing for Chapter 7 bankruptcy in the U.S. Bankruptcy Court for the District of Delaware on October 13, 2023.