iSpecimen operates an online marketplace that connects life science researchers with human biospecimens — blood, tissue, cells, and other biological samples — sourced from a network of healthcare providers. Customers, primarily biopharma companies, in vitro diagnostic firms, and academic and government institutions, use the platform to search for specimens matching specific study criteria, request quotes, place orders, and track fulfillment. iSpecimen handles contracting, compliance, and logistics on both sides of each transaction. The core value proposition is aggregating specimen inventory from dozens of healthcare organizations into a single searchable platform, replacing a fragmented, manual procurement process. iSpecimen offers two broad specimen categories: remnant specimens, which are leftover clinical samples no longer needed for patient care, and research use only (RUO) specimens, which are collected specifically for research with patient consent. RUO biofluids represent the largest share of revenue, followed by remnant biofluids and RUO tissue. iSpecimen makes money by selling specimens to researchers and sharing a portion of revenue back with the supplying healthcare organization. The company operates on a just-in-time model, procuring specimens only after receiving an order rather than building inventory speculatively. Customer demand is episodic and project-based, and revenue is concentrated — the top customer has represented roughly 20–29% of total revenue in recent years. iSpecimen's supplier network spans 73 organizations across 14 countries. The company is also exploring data monetization, leveraging de-identified clinical data aggregated across its network, with its NGS tissue product — which pairs sequenced tumor tissue with clinical annotation — as an early example of this approach.