Define Ventures Research
Executive Summary
Define Ventures is one of the largest venture capital firms exclusively focused on early-stage digital health companies. Founded by Lynne Chou O'Keefe, the firm manages $800 million in assets under management across six funds and has established itself as a category-defining investor in healthcare technology. The firm combines deep healthcare expertise with a technology-driven mindset, creating a powerful partnership model for healthcare entrepreneurs.
Investment Thesis
Define Ventures operates on a foundational belief that the future of healthcare will be fundamentally transformed by the convergence of rapid technology innovation, evolving consumer preferences, and seismic shifts within the healthcare industry itself. The firm explicitly aims to partner with entrepreneurs who can bridge the gap between deep understanding of healthcare ecosystem complexities and modern technology solutions.
The firm's philosophy emphasizes that healthcare innovation requires more than just capital—it demands operational expertise, access to healthcare decision-makers, and strategic guidance from leaders who have built category-defining companies at scale. Define Ventures positions itself as a true operating partner committed to driving measurable shareholder value through network leverage, strategic relationships, and hands-on support.
Sector and Stage Focus
Primary Sector: Digital Health / Healthcare Technology
Define Ventures invests exclusively in the healthcare sector, with particular emphasis on:
- Digital health platforms - Direct-to-consumer and B2B2C health technology
- Value-based care enablement - Technology for healthcare providers and payers
- Healthcare infrastructure - Clinical operations, data, and workflow optimization
- AI/ML in healthcare - Emerging applications transforming clinical and administrative functions
- Population health - Employer, payer, and provider solutions for managing health outcomes
Investment Stages
Define Ventures invests across the full spectrum:
- Pre-seed / Incubation (through in-house incubator)
- Seed stage ($1M-$5M typical)
- Series A ($5M-$15M typical)
- Selective Series B follow-ons
The firm operates a structured incubation program and runs an AI Fellows program that identifies and trains next-generation healthcare AI founders.
Portfolio Highlights
Public Companies:
- Hims & Hers (NYSE: HIMS) - Direct-to-consumer health and wellness platform, primary success
Category-Defining Companies:
- Unite Us - Community health platform connecting individuals to services
- Cohere Health - AI/ML for clinical approval and administrative automation
- FOLX Health - LGBTQIA+ specialized digital health platform
- Centivo - Self-funded employer health plans
- Blackbird Health - Mental healthcare for young people
- Tia - Women's health clinic model
- Found - Weight care and metabolic health platform
- Story Health - Home-based health coaching with AI clinical support
AI/Automation Focus:
- Layer Health - Clinical data extraction and understanding
- Hyro - Healthcare conversational AI
- Solara Health - AI-driven clinical workforce automation
- Luminai - Business process automation for healthcare
- Laudio - Healthcare workforce retention through AI
Clinical Trial & Life Science:
- Crescendo Health - Real-world data for clinical trials
- Lightship - Hybrid clinical trial operations
- Double Blind Bio - Clinical trial site automation
- Verana Health - Real-world clinical data insights
Enterprise/Payer Solutions:
- Dexcare - Patient access optimization
- Fair Square Medicare - Medicare sales automation
- Marit Health - Clinician compensation transparency
Team and Leadership
Define Ventures is led by Lynne Chou O'Keefe (Founder & Managing Partner) with support from Venture Partners Bruce Broussard, Frank Williams, and Carolyn Magill. The firm maintains a best-in-class advisory board including healthcare titans (Toby Cosgrove - Cleveland Clinic, Peter Fine - Banner Health, Beth Bierbower - Humana) and technology leaders (Jia Li - Google AI/ML, Ashley Yuki Alexander - OpenAI Healthcare Head).
Geographic Focus
Based in San Francisco, California, with US-wide investment scope.
Lead Tendency
Define Ventures is a lead investor that actively drives governance and strategic decisions. The firm takes board seats and provides direct access to healthcare system relationships (72% of portfolio companies have customers within Define's coalition of healthcare organizations). Portfolio support includes talent recruitment (2 in 3 companies have senior talent placements) and capital raising support ($1.6B raised by portfolio companies in follow-on funding).
Recent Activity
Define Ventures maintains active deployment with recent investments in 2025 including Hyro (October 2025) and Layer Health (December 2025). The fund has established itself as thought leader on healthcare AI with market research publications through their AI + Healthcare Summit.
Fund Performance
- AUM: $800 million across 6 funds
- Exit Value: $23 billion cumulatively
- Portfolio Companies: 60+ active investments plus stealth/incubation
- IPO Success: Hims & Hers (NYSE: HIMS) represents major public company success
Conclusion
Define Ventures combines singular healthcare sector focus, substantial capital scale, proven returns, and operational leverage through direct healthcare system relationships. The firm represents the gold standard for early-stage healthcare venture capital and serves as strategic operating partner for healthcare entrepreneurs with technical excellence and domain expertise.