Company leader
Zachary Ziegler
Co-founder and CTO
OpenEvidence
Zachary Ziegler is co-founder and chief technology officer of OpenEvidence, whose AI search engine gives doctors answers drawn from medical research, with a citation for each claim. He leads the technical work behind its search product and DeepConsult, a feature that researches a clinical question across many studies.
Machine Learning Research at Harvard
He was working on a PhD in machine learning at Harvard, in Alexander Rush's natural language processing lab, with a National Science Foundation Graduate Research Fellowship, when he teamed up with Daniel Nadler in 2021.
Co-founding OpenEvidence
He has said the idea came partly from watching his brother-in-law, then 22, go through treatment for leukemia, and seeing that doctors still found answers by leafing through textbooks. His brother-in-law is now in remission. He and Nadler founded OpenEvidence in November 2021.
In July 2025 OpenEvidence launched DeepConsult, which uses reasoning models to connect findings across different studies. He described it as giving a physician a team of MD-PhDs who research a topic while the physician does other work.