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With backgrounds in investment & finance,  technology & product development, and human resources & business processes the VC23 team covers the complete spectrum of the new business start-up experience.   Get in touch with us if you are looking for venture funding or investment opportunities.

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Nat Brinn

General Partner

Nat Brinn has a successful track record over 30 years of private investments, acquisitions and business management. He has been a partner of Vital Venture Capital since founding the firm in 2007. Vital invested in 22 early-stage biotechnology and software companies and he served on the boards of many of these companies. 

Prior to his venture capital career, Nat was CEO of HSA Bank, a division of Webster Bank. He led the acquisition of HSA Bank for Webster and grew the operation starting from $95 million in deposits. HSA Bank now has over $6 billion of deposits and is the largest specialty bank in the United States focused on health savings accounts. While he was Executive Vice President of Corporate Development at Webster Bank, Nat was responsible for mergers and acquisitions as well as strategic initiatives. Prior to his tenure at Webster Bank, Nat held various positions in M&A and private placement institutional investments.

Nat has an MBA in finance and accounting from Duke University and did his undergraduate work at University of Delaware in Economics and Mathematics. His volunteer work includes the National Federation for Teaching Entrepreneurship, mission projects and other activities. Nat and his college sweetheart wife Kim enjoy visiting their adult daughters in Boston. Nat stays outdoors as much as possible sailing, skiing and gardening. He also plays bass and keyboards in several bands. While awaiting musical stardom he continues to work his “day gig” as a venture capitalist.


Ron Evans

General Partner

Ron Evans has been actively assessing and advising entrepreneurial organizations for more than 30 years. He has been an active angel investor and advisor to early stage technology companies for the past 15 years. Prior to VC23 he worked with numerous private equity and venture capital investors providing management assessment and executive selection. His earlier career includes extensive HR consulting with Fortune 500 and privately-owned companies while serving as Managing Director and Chairman of SIMA International, Partner with Ward Howell International, and Senior Manager with Ernst & Young.


Ron is internationally known for his behavioral and motivational assessment and his ability to deeply understand business leaders and their teams. He is passionate about helping senior executives and entrepreneurs discover their innate strengths and leverage them to maximize business results.


A graduate of the University of Connecticut, Ron has been featured in the Wall Street Journal online edition (see and is author of the popular executive guidebook “Kiss Your Resume Goodbye”. He is active in several urban ministries serving under resourced people in Connecticut and Texas. Ron has been married to the love of his life, Cindy, for more than 30 years. They have three adult sons.​

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Tim Sullivan

Venture Partner

Tim Sullivan has 35 years of experience in drug development across a variety of therapeutic areas such as autoimmune diseases, immuno-oncology, and infectious disease. His responsibilities at the VP level have included strategy and execution of development programs, management of collaborative alliance relationships, regulatory affairs, clinical pharmacology, manufacturing, and nonclinical development. He has led Investigative New Drug interactions with the US FDA divisions of Pulmonary, Allergy and Rheumatology Products; Dermatology and Dental Products; Oncology Products; Hematology Products; Antiviral Products and comparable international regulators. He also has experience with orphan drugs and companion diagnostics.


Tim has a Ph.D. from Purdue University and a B.S. from Michigan State. Tim has been contributing to the VC23 team due diligence of investment opportunities and continuing his involvement with drug development strategies through selected consulting arrangements. Tim and wife Lori are happy to be geographically between their son in Boston and their daughter’s family in Philadelphia.


Alan Mendelson

Venture Partner

Alan was the founder in 1994 and Managing General Partner of Axiom Venture Partners. In its 21 year history, Axiom managed 3 funds with an aggregate of $200 million under management. The funds generated a net IRR of 16% and returned about 2.1x capital. Alan was responsible for investing $70 million of that amount which generated $180 million of proceeds for a 2.6x return.

Prior to founding Axiom, Mr. Mendelson had a 24-year career in investments at Aetna Life & Casualty in Hartford, Connecticut where he was involved in over $3.0 billion of private placement debt financing with estimated combined losses of under $10 million. For the last 10 years at Aetna, he was responsible for building its $135 million venture capital portfolio of direct and partnership investments. In his last six years at Aetna, he focused its venture investing on the medical/healthcare area, where he made a number of successful investments, including GMIS, Geron, Human Genome Sciences and SyStemix. In several of these companies, he was a founding investor, and in the case of SyStemix also its de facto CEO. Overall the $65.0 million portfolio of direct investments generated approximately $265 million of proceeds.


In addition, he was a co-founder of Thermoscan, Inc., which became a $100 million subsidiary of Gillette. Mr. Mendelson is presently on the Investment Committee of Connecticut Innovations, Inc., the State of Connecticut’s venture fund with a portfolio in excess of $60 million. He also serves on the Boards of the Connecticut Technology Council and the MIT Enterprise Forum. Mr. Mendelson is on the Keck Institute Advisory Board and was on the Advisory Board of Battery Ventures and Syncom, two well-known venture capital firms.


Previously, he was the President and CEO of Aetna, Jacobs, and Ramo, where under his direction, ES Jacobs and Company realized approximately $200 million on $40 million of invested capital. He has also done extensive consulting on the entrepreneurial activities of several large companies including Glaxo, Texas Instrument, DuPont and IBM. Mr. Mendelson concentrates on the biopharmaceutical sector, particularly therapeutics. Mr. Mendelson has an undergraduate degree in economics and a law degree.


Parag Jhaveri

Venture Partner

Parag Jhaveri has 18+ years of experience in corporate strategy, M&A, commercialization, and venture capital investing for Life Sciences, Tools & Diagnostics, and working with PE clients and early-stage venture-backed companies. 


Prior to his venture capital career, Parag was an Associate Partner with Accenture's Strategy & Consulting practice focused on strategy consulting and M&A. Before Accenture, he was with McKesson’s Specialty Health Business unit as a Director of Corporate Strategy and Business Development where he focused on operating model changes, strategic planning, and M&A. He also worked for KPMG’s Healthcare Deals Advisory practice focused on due diligence, strategy, and data analytics for corporate and PE companies. He has strong operational and commercialization experience from Life Technologies' (acquired by ThermoFisher Scientific for $14B) NGS business unit and Becton, Dickinson, and Company's Cancer Diagnostics business unit.


Parag holds an MBA from Haas School of Business, UC Berkeley, after receiving a Masters in Industrial Engineering from Louisiana Tech University and Bachelors in Mechanical Engineering from the University of Mumbai. He volunteers as a Medtech Selection committee member for EvoNexus, a non-profit technology incubator, and serves as a mentor for UCSF Health Hub.


Ralph Vossmeyer

Venture Partner

Ralph Vossmeyer - As an independent consultant, investor and prior executive leader for Teradata, a San Diego Analytics company, Ralph creates success by enabling idea-based cultures that challenge the status quo. His inclusive leadership style is focused on innovation and based on analytical foundations. This has led to developing investing models based on market disruption that he uses in the venture capital markets as well as in managing investments in public markets. He is a lifelong learner and currently in the middle of a Stanford Genomics program. His background spans P&L, general management, business operations, sales, marketing, consulting/professional services, and R&D. Through his leadership approach, the companies he has served have captured hundreds of millions of dollars in new revenue and cost savings. 


Ralph is also deeply invested at Walters’s Walk, a non-profit organization that promotes psychological and emotional wellness through a team of dedicated professionals. 


Ralph holds an Executive MBA from Washington University and a BS degree in Computer Science from the University of Missouri.

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