AI Search Startup Used by Two-thirds of U.S. Doctors Eyes $500M in Ads
WHO:
Ars Technica - OpenEvidence is an AI search startup used by doctors.
Techmeme - OpenEvidence’s founder said nearly two-thirds of approximately 1 million U.S. physicians use its AI search engine.
Techmeme - The user figures and advertising-revenue estimate were attributed to OpenEvidence and an unnamed source, respectively; the article was written by Rafe Rosner-Uddin of the Financial Times.
WHAT:
Fast Company - About one-third of Americans have used AI for health information, and one in four did so in the past month.
Fast Company - OpenEvidence consultations rose from about 3 million per month to about 18 million per month over a year, reaching that level in December 2025.
Fast Company - Across industries, 88% of AI pilots never reach production; a National Bureau of Economic Research working paper found only about one in 10 companies reported AI-related productivity gains over the preceding three years.
Fast Company - A Lancet journal study found experienced endoscopists’ detection rate without AI fell from 28.4% to 22.4% after they became accustomed to using AI, below their pre-AI rate.
Ars Technica - OpenEvidence was described as a $15 billion, ad-powered AI startup.
Ars Technica - The article said OpenEvidence was growing despite questions about its accuracy and advertising.
Techmeme - A source said OpenEvidence was on track to generate $400 million to $500 million in advertising revenue in 2026.
Techmeme - The article described debate over the ad-powered tool’s implications for patient care.
WHERE:
Fast Company - Researchers developed a breast-cancer prediction model using mammograms from multiple hospitals without the hospitals sharing patient data.
Techmeme - The reported physician users are in the United States.
WHEN:
Techmeme - The $400 million to $500 million advertising-revenue estimate is for 2026.
WHY:
Ars Technica - Questions about OpenEvidence’s accuracy and advertising were noted alongside its growth.
Techmeme - OpenEvidence’s use by physicians has prompted debate about patient care.
HOW:
Fast Company - The model detected which hospital an image came from by identifying scanner-related differences, a shortcut engineers removed during training. The resulting model became the first FDA-authorized AI to predict a woman’s five-year breast cancer risk from a mammogram alone.
Techmeme - OpenEvidence provides an AI search engine for physicians and is ad-powered.
(UPDATED October 21, 2026 20:22 UTC)
OpenEvidence, an ad-supported AI search engine for doctors, says nearly two-thirds of about 1 million U.S. physicians use its service. Its consultations grew from roughly 3 million a month to 18 million a month over a year, and the company is valued at $15 billion. An unnamed source estimates it could bring in $400 million to $500 million in advertising revenue in 2026, even as questions persist about accuracy and the effects of ads on patient care. Meanwhile, about one-third of Americans have used AI for health information, with one in four doing so in the past month. Research also highlights risks: a study found experienced endoscopists detected fewer abnormalities without AI after becoming accustomed to using it. In another development, researchers built a breast-cancer risk model using mammograms from multiple hospitals without sharing patient data.
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(UPDATED October 21, 2026 19:22 UTC)
OpenEvidence, an ad-powered AI search startup for doctors, is valued at $15 billion and is gaining widespread use among U.S. physicians. Its founder says nearly two-thirds of the country’s roughly 1 million doctors use the company’s search engine. OpenEvidence is on track to bring in between $400 million and $500 million in advertising revenue in 2026, according to an estimate attributed to an unnamed source. The company’s growth has drawn attention to questions about the accuracy of its answers and the role of advertising in a tool used for medical research. Its popularity has also prompted debate over what ad-powered AI search could mean for patient care. The user count is attributed to the company, while the revenue estimate comes from a source whose identity was not disclosed.