Photo: -Sasa-Delic-SD/Getty Images
OpenEvidence, an AI-enabled medical research aggregate platform for doctors, has closed a $250 million Series D funding round, bringing its total raise to nearly $700 million over the past 12 months and doubling its valuation to $12 billion.
Thrive Capital and DST Global led the round.
The company said previous investors include Sequoia, Google Ventures, NVIDIA, Kleiner Perkins, Blackstone, Henry Kravis, Coatue, Thrive Capital, Conviction, ICONIQ, Greycroft, Breyer Capital, BOND, Craft Ventures, Goanna, Meritech, Alkeon, Mayo Clinic and others, and many of those entities also followed on in the Series D round.
WHAT IT DOES
OpenEvidence is a free medical information platform that offers an AI-enabled medical copilot for doctors in the U.S. trained only on medical journals and medical data. It aggregates and synthesizes clinical information to help doctors make more evidence-based decisions.
The company's AI is trained on specialized content through strategic collaborations, including partnerships with the New England Journal of Medicine, the American Medical Association, the National Comprehensive Cancer Network and the American College of Cardiology.
OpenEvidence will use the funds to invest in research and development and compute costs associated with its multi-AI agentic architecture.
"If a doctor tried to stay current by reading only the new evidence in the top 10 medical journals and only the most recent changes to their specialty guidelines, it would take nine hours of their day, each day," Daniel Nadler, founder and CEO of OpenEvidence, said in a statement.
"Without a technology like OpenEvidence, doctors may miss critical new findings or guidelines simply because they lack the time to find them. Doctors want to provide the best care to patients. OpenEvidence is the tool that safely allows them to do that. Our mission is to help doctors save lives and improve patient care."
MARKET SNAPSHOT
In February 2025, OpenEvidence raised approximately $75 million in Series A funding at a $1 billion valuation, bringing it to unicorn status.
That same month, OpenEvidence filed a lawsuit in the United States District Court for the District of Massachusetts against Montreal-based Pathway Medical, a company that provides AI-driven clinical decision support.
The suit alleged that Pathway engaged in "brazen efforts, over a period of many months, to compromise OpenEvidence’s leading artificial intelligence (AI) medical information platform using stolen credentials and malicious inputs, steal OpenEvidence’s highly valuable trade secrets and utilizing this stolen information, develop a 'copycat' company and platform that directly competes with OpenEvidence."
Additionally, the complaint claimed the "defendants improperly and under false pretenses invaded the OpenEvidence AI platform repeatedly, executing dozens of 'prompt injection' attacks, a type of cyberattack that is uniquely harmful to AI systems in which hackers and other bad actors disguise malicious inputs as legitimate prompts, which are designed to bypass the restrictions implemented on a generative AI (genAI) system and manipulate that system into divulging sensitive and proprietary information or worse."
In June, OpenEvidence sued Doximity, a networking platform for healthcare professionals, for alleged "prompt-injection attacks," claiming that Doximity reps posed as doctors to manipulate its generative AI system into revealing proprietary code, allegedly "reverse-engineering" its AI.
Doximity filed a counterclaim in Massachusetts federal court, alleging that OpenEvidence was spreading false information to harm its reputation and lure away its employees.
In July, OpenEvidence raised $210 million in Series B funding at a valuation of $3.5 billion.
One month later, Doximity acquired Pathway Medical in a deal worth $63 million. Doximity said the transaction closed on July 29, for "cash consideration of $26 million and not exceeding $37 million in additional equity grants."
In September, Doximity filed a Motion to Dismiss the case with OpenEvidence, alleging "OpenEvidence’s complaint is based on speculative assertions that do not and cannot support a claim for misappropriation of trade secrets or any other violation of federal or state law. Because any amendment would be futile, the complaint should be dismissed with prejudice."
The litigation is ongoing.
In October, OpenEvidence scored $200 million in a Series C round, boosting its valuation to $6 billion.
