Tennr raised $101M to stop half of referred patients from falling through the cracks

Tennr is a New York health tech company whose document-understanding model automates the patient referral process between primary care and specialists.

$101 million Series C led by IVP with Google Ventures and Iconiq participating and existing investors Andreessen Horowitz and Lightspeed, at a $605 million valuation — less than a year after a $37 million Series B.

Diego Baugh met the problem as a college patient: hospitalized with stomach issues, told to see a specialist, and left waiting six weeks — twice. Co-founder Trey Holterman, a software engineer at Medicare platform Health IQ and Strava, had heard his mother, a family medicine practitioner, complain about referrals for years: "I probably should've just listened to my mom sooner." They founded Tennr in 2021 with Tyler Johnson.

The founders began building their own specialized model before ChatGPT arrived, trained on tens of millions of medical documents for referral use cases; Holterman says betting on open source plus a proprietary dataset "continues to totally smash benchmarks," and Tennr complies with HIPAA through de-identification. Zeya Yang invested at Series A at Andreessen Horowitz and followed the company to IVP to lead the Series C, seeing a strategic wedge to expand into new medical subverticals, referral-workflow tools like insurance verification, and a network feature giving primary care physicians and patients visibility into referral and payment status.

The referral paperwork layer is high-volume, high-friction and hyper-specific — perfect for a specialized model, unattractive for generalist AI labs.

The wedge expands: subverticals within medical specialties, new workflow tools like insurance verification, and a network feature for patients and referring physicians.

Follow-on capital from the same partner (Zeya Yang, a16z Series A to IVP Series C) signals durable conviction in the wedge.

Eight-figure revenue tripling year-over-year made it one of the fastest-growing health tech startups in an AI-dominated vertical.

In AI markets, the defensible model is trained on data too boring for generalists: referral paperwork is Tennr's moat precisely because OpenAI won't chase it.

As of the 18 June 2025 report, Tennr was expanding into new medical subverticals, building referral-workflow tools such as insurance verification, and rolling out a network feature giving primary care physicians and patients visibility into the referral and payment process.