We’ve built healthcare unicorns. Now we’re building the system they all should’ve run on.

Our Mission

We didn’t set out to build another point solution.

We’ve lived the problem - as operators, investors, clinicians, and technologists across some of the most complex corners of healthcare. We’ve built and backed billion-dollar health companies. We’ve run national provider networks, health plans, MSOs, and pharmacies. We’ve architected systems that scaled to hundreds of millions of users. And through all of it, we saw the same thing: fragmentation, friction, and guesswork.

Arbiter was born from that frustration.

Not another widget, but the intelligent system healthcare should have had all along - modular, AI-native, and built to unify data, technology, and players to power better care.

This isn’t a consulting spinout or a VC experiment. Arbiter is purpose-built by the buyers - and deployed through the very payers and providers who demanded it.

Leadership

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Michelle Carnahan

Co-Founder, board member, CEO

Commercial strategist with the bias for execution healthcare has lacked. Previously Thirty Madison, Eli Lilly, Sanofi

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Anjali Jameson

Chief Product Officer

Product leader who turns messy workflows into tools people love. Previously One Medical, UnitedHealth, Apple

Julian Nagler

head of Strategy & Ops

Systems thinker who finds signal in the chaos and builds around it. Previously Meta, TriEdge Investments

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Peter Schaefer

Chief Architect

Technical leader who builds systems that make health data work in the real world. Previously MFO Ventures, Loblaw Digital

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Tyler Crane

Head of Commercial Partnerships

Growth operator who sees the white space and turns it into distribution. Previously Thirty Madison, Strategy&

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Hannah Heider

Chief of staff

Force multiplier who keeps vision, people, and priorities perfectly in sync. Previously W, GoHealth

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Eric Moskow, MD

Co-Founder, Board Member

Physician and investor with deep experience founding and scaling payer, provider, and pharmacy platforms. CEO of MFO Ventures

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Simcha Hyman

co-founder, Board Member

Founder and operator of leading post-acute, pharmacy, and value-based care companies. CEO of TriEdge Investments

Board

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Bren Hall, CFA

Partner, WindRose Health investors

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Bob Wachter, MD

Chair, UCSF Dept of Medicine

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Clive Fields, MD

Co-founder, VillageMD

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The Hon. David Shulkin, MD

9th VA Secretary

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Elliot Moskow

Repeat Startup Founder

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Everett Neville

EVP of Strategy, Cigna

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Joe Brunink

CEO, OI Infusion

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Mary Beth Lang

CPO, Kaiser Permanente (Former)

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Richard Becker, MD

NY Deputy Secretary of Health (former)

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Vincent Tammaro

CFO, Mount Sinai

Advisors

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Ainsley MacLean, MD, FACR

Chief Ai Officer, Kaiser Permanente (former)

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Jen Clair

CFO, village Medical (former)

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Aran Ron, MD

Chief Medical Officer, Oscar Health (former)

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Winston Esposito

Product Leader, Ai Startup CEO

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Alex Chen, MD

Primary Care Doc, Engineer

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DeLyle Manwaring

President, Millennium Physicians