Ebb & Flow

Investors who have followed Mark Levin's lead have rarely been disappointed. Thus it's no surprise that his new venture fund, Third Rock Ventures, raised $378 million in only 10 weeks on the road.

Founded by former executives from Millennium (MLNM), Third Rock's selling point is hands-on company management, founding partner Kevin Starr told Ebb & Flow. What resonated with investors is "how we think about building great companies from an operating perspective."...