Leonard Rinser is an entrepreneur in the health and life science space.
With the Venture Institute he runs an AI-first venture builder for health and life sciences, working with Europe’s leading research organizations, scientists and founders to commercialize breakthrough technologies, from first idea to market-ready company. The Institute combines strategic advisory, operational (co-)building and early-stage investment support in a systematic, research-based approach.

As the voice behind the media brand The Health Guy, he covers AI in health, prevention and longevity for a global audience of clinicians, founders and investors, work for which Favikon named him one of the World’s Leading Voices in Digital Health 2026.

Leonard collaborates with leading research institutions including the Fraunhofer Society, the Max Planck Society and teams from the Helmholtz ecosystem. As Global Health Executive of the Sigma Squared Society he supports over 200 founders across 30+ countries, serves as Venture Partner for several investment funds, and mentors at accelerators including Plug & Play, Start2 Group and the Life Science Factory.