Warren Buffett famously said that when he owns outstanding businesses with outstanding management teams, his favourite holding period is “forever”. Fix-and-flip private equity bosses have come round to his way of thinking.

Evergreen funds, which do not need to return money to investors within the decade or so of the traditional closed-end fund, are taking off. Their number has doubled over the past five years and they now account for $350bn of net asset value, according to Preqin. That is still small beer, and largely focused on real estate, private credit or buyout strategies that piggyback on existing traditional funds. But the industry hopes it will grow into a standalone asset class. 

It is not hard to see why. The time constraints of closed-end funds are increasingly onerous. Raising a fund and then looking for companies to buy means that a lot of cash is sitting on the sidelines, damping overall returns.