Firms

Define Ventures

Define Ventures

San Francisco, California, United States

definevc.com

Define Ventures is a San Francisco venture capital firm focused on early-stage healthcare technology, including AI-enabled clinical and administrative tools, digital health, care delivery and patient engagement. Founded and led by Lynne Chou O’Keefe, it combines venture investing with healthcare operating experience and a published network of commercial, clinical, AI, technology and communications advisers. The legal adviser is Define Ventures Management, LLC, CRD299671, which reports to the SEC as an exempt reporting adviser (file802-114577), rather than an SEC-registered investment adviser. Its March2026 FormADV identifies six private fund vehicles. The firm’s website describes USD800M in assets under management, which is not a new closed fund. Its April18,2023 announcement reports USD460M raised across FundIII and an Opportunities fund combined; no individual fund split is inferred. Its portfolio includes healthcare AI companies and Readily, which names Define among its backers. This US healthcare investor is distinct from the Canadian DefinedVC firm.

Founded
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Type
Venture capital

Funds6

  • DEFINE VENTURES FUND III, L.P.—

    Exact Delaware legal private fund identified in the March27,2026 FormADV. FundIII and OpportunitiesII/III are joint issuers of the July15,2022 SEC FormD. Define announced USD460M raised across FundIII and an Opportunities fund combined onApril18,2023; the primary disclosures do not establish an individual final amount or an allocation between the vehicles. Fund III’s individual amount remains undisclosed; its joint close announcement is dated April 18, 2023. The combined total is preserved as qualified context rather than double counted.

  • DEFINE VENTURES FUND II, L.P.$200M

    Delaware FundII legal vehicle identified by current FormADV805-4687254223. January12,2021 SEC FormD/A discloses USD200M fully sold to37 investors, zero remaining, with first saleOctober16,2020. Filing disclosure date is not an inferred exact cash-close date.

  • DEFINE VENTURES FUND I, L.P.$87M

    Delaware FundI legal vehicle identified by current FormADV805-4678041852. January13,2020 SEC FormD/A discloses USD87,575,757 fully sold to23 investors, zero remaining; signature datedJanuary10, first saleOctober16,2018. The record uses filing disclosure date, not a guessed final cash-closing day.

  • DEFINE VENTURES OPPORTUNITIES I, L.P.—

    Exact Delaware private fund legal vehicle identified in the March27,2026 FormADV. Final closed commitments and exact closing/public-announcement date are not established. Current fund gross asset value, firm assets under management and management fees are not recorded as fund cash.

  • DEFINE VENTURES OPPORTUNITIES II/III, L.P.—

    Exact Delaware legal private fund identified in the March27,2026 FormADV. FundIII and OpportunitiesII/III are joint issuers of the July15,2022 SEC FormD. Define announced USD460M raised across FundIII and an Opportunities fund combined onApril18,2023; the primary disclosures do not establish an individual final amount or an allocation between the vehicles. Individual amount/date remainNULL; the combined total is preserved as qualified context rather than double counted.

  • DEFINE VENTURES SELECT I, L.P.—

    Exact Delaware private fund legal vehicle identified in the March27,2026 FormADV. Final closed commitments and exact closing/public-announcement date are not established. Current fund gross asset value, firm assets under management and management fees are not recorded as fund cash.

Team

Frank Williams
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Operations and support

A.G. BreitensteinA.G. BreitensteinHealthcare Advisor
Amanda DuckworthAmanda DuckworthCommunications Advisor
Ashley Yuki AlexanderAshley Yuki AlexanderFormer Consumer Advisor
Bangaly KabaBangaly KabaConsumer Advisor
Beth BierbowerBeth BierbowerHealthcare Advisor
Brook ByersBrook ByersFund Advisor
Bruce BroussardBruce BroussardVenture Partner
Carolyn MagillCarolyn MagillVenture Partner
Chirag ShahChirag ShahPartner
Chuka EsiobuChuka EsiobuPrincipal
Debby MeredithDebby MeredithTech Advisor
Erin HardyErin HardyAccounting & Operations Manager
Garrett HowardGarrett HowardPrincipal
Hong TruongHong TruongPrincipal
Jia LiJia LiAI Advisor
Jim PursleyJim PursleyCommercial Advisor
Karsten VagnerKarsten VagnerHead of People
Katharine MorrisKatharine MorrisAdministrative Assistant & Office Manager
Lauren O'MahonyLauren O'MahonyHead of Marketing
Lynne Chou O'KeefeLynne Chou O'KeefeFounder & Managing Partner
Michael WertMichael WertPartner
Nigam ShahNigam ShahAI Advisor
Peter FinePeter FineHealthcare Advisor
Seth CohenSeth CohenCommercial Advisor
Shannon KnousShannon KnousVP of Finance & Operations
Toby CosgroveToby CosgroveHealthcare Advisor

Co-investing

Flare Capital Partners
Deerfield
Longitude
Polaris Partners
Foundry Group
  • WHOOP$— · Unknown date

Investments