When Swedish private equity firm EQT Partners was raising its latest flagship private equity fund, it decided not to invite Ontario Teachers’ Pension Plan to join in. Many private equity firms would love to receive backing from one of the largest institutional investors in the world. But there was a problem.

Ontario Teachers' Pension Plan is one of a band of investors increasingly looking to buy the same sort of companies the EQT likes to acquire. Having been unable to invest in EQT's new fund, which closed at its upper limit of €6.75 billion in August 2015, OTPP then decided to end its relationship with EQT by selling its interests in the firm's prior funds on the market for second-hand fund stakes.