OpenEvidence is an American artificial intelligence company founded in 2021 by Daniel Nadler and Zachary Ziegler that develops a medical search and clinical decision support engine for physicians. The platform is designed to give clinicians fast, evidence-grounded answers to medical questions at the point of care, drawing on peer-reviewed literature and trusted clinical sources.
The core product is a question-answering system that synthesizes the medical literature and returns concise, citation-backed responses. The emphasis on linking answers to underlying sources is central to its positioning, since clinical trust depends on traceability to evidence rather than unattributed model output. The company has pursued partnerships with major medical publishers to ground its answers in authoritative content.
OpenEvidence targets practicing physicians and other clinicians as its primary users, with adoption reported across a substantial share of US physicians. Its value proposition is reducing the time required to find and synthesize relevant evidence during clinical workflows, where speed and reliability are critical.
The company has attracted significant investor attention and a high valuation, reflecting both the size of the clinical information market and the strategic value of trusted, evidence-linked medical AI. Daniel Nadler, who previously founded Kensho, brings prior experience scaling an AI company acquired by S&P Global.
OpenEvidence operates in a high-stakes domain where accuracy, citation integrity, and regulatory and liability considerations are paramount. It is best understood as a clinician-facing decision-support tool rather than a patient-facing diagnostic product, and its responsible use depends on professional clinical judgment.