Zach Weinberg

Zach Weinberg co-founded Flatiron Health (sold to Roche for $1.9B) and Invite Health, then started Operator Partners. He is one of the more credible health tech operator-angels working today and is openly active on Twitter as a sparring partner for founders. His angel checks lean into digital health, tech-enabled care delivery, and healthcare software, the categories he knows from Flatiron, with a strong preference for companies that have to navigate real provider workflows or payer contracts, not just consumer wellness. AI focus is not flagged as primary; he is a software/data person more than a model person. $100k-$250k at pre-seed through Series A, often as a smaller but very high-signal check on a round. New York-based, US-focused. Best fit: founders building real provider, oncology, or specialty care infrastructure, RCM, clinical data, or anything where Flatiron-style data and workflow chops are useful, especially if you have a credible clinical or operator co-founder. Pure consumer brand, biotech, or hardware founders should look elsewhere. Entry path: he reads Twitter DMs and the public threads make his preferences clear; LinkedIn works too. He will reject bad ideas crisply and quickly, which is itself useful. Bring him a product diagram, a contract structure, and a real customer, not a vision deck.