William Blair Capital Partners

William Blair Capital Partners was founded in 1982 to serve as the investment arm of the investment bank William Blair & Company. During the 1980s, the firm was an active investor in leveraged buyout transactions. The team raised and deployed six funds as a core group within the bank before raising a seventh fund, William Blair Capital Partners VII, which closed in 2001 with $403 million.

In 2004, the senior partners of the group completed a spin-out from William Blair & Company to form Chicago Growth Partners. The primary motivation for the spin-out was to gain access to a more diversified base of institutional investors, moving away from the limitations of being tied to the investment bank. This transition occurred during a broader trend where several major investment banks spun off their private equity units.

The successor firm, Chicago Growth Partners, continued to focus on middle-market companies across several key industries. In 2008, the firm successfully raised $500 million for its second independent fund. However, despite plans to raise a third fund starting in 2012, the firm reportedly abandoned those efforts in 2014 and effectively ceased new fund activity.