Healthcare platform Arbiter has raised US$52m in seed funding from family offices, valuing the New York company at about US$400m.
The start-up, which aims to reduce fragmentation in healthcare systems, secured backing from specialist healthcare investors including TriEdge, MFO Ventures and WindRose Health Investors rather than traditional venture capital firms.
The investors bring operational experience from companies including Cigna, UnitedHealth, Kaiser Permanente, One Medical and VillageMD, while their technical teams have backgrounds at Meta, Apple, Google and Amazon.
“Arbiter’s mission is nothing less than to rebuild the operating spine of US healthcare,” said co-founder and chief executive officer Michelle Carnahan, who previously spent decades at Eli Lilly.
“By aligning payers and providers around the needs of patients, we’re transforming healthcare from a fragmented set of parts into a connected system that works for everyone.”
The company accelerated its development by acquiring a data platform, customers and some staff from SecondWave Delivery Systems.
The acquisition provided a functioning data layer that consolidates patient records from different systems and evaluates risk, reportedly saving 18 months of development time whilst bringing contracted multi-year revenue.
The acquired platform already handled clinical factors and risk adjustment, which involves calculating patient complexity to ensure fair healthcare payments.
This foundation enables Arbiter to deploy AI agents that can act on insights rather than simply flagging issues.
The company’s AI tools are currently in use with more than 1,000 clinicians.
Its first application uses AI agents to contact patients, book appointments and run follow-up communications after visits.
The backing comes from three family offices specialising in healthcare investment: Simcha Hyman’s TriEdge, Eric, Elliot and Jeremy Moskow’s MFO Ventures based in Delray Beach, Florida, and WindRose Health Investors.
Family office backing can provide specialised knowledge and distribution relationships that typically take years for venture-funded start-ups to build.
In healthcare, where partnerships with payers and provider networks develop through slow, trust-led processes, these investors can help with introductions to pilot partners and structuring contracts.
However, family offices may expect tighter commercial timelines or specific strategic moves than traditional venture capital.
For founders like Carnahan, this route offered both speed and market access for a mission-focused product.
The platform aims to create what it calls an “operational spine” that could reduce handoffs between systems and save clinician time.
Success will depend on whether the automation proves safe, explainable and integrates smoothly into clinical workflows.
Key considerations for clinics include whether the AI agents sound natural, handle patient data securely, and reduce appointment no-shows.
Providers will assess whether automation reduces workload or merely shifts it, whilst patients will judge whether outreach feels helpful or intrusive.
