Mainstream asset managers and investment bankers were first irritated, then became worried. Those pesky private equity firms have come in from the fringe and, in M&A and IPOs, are becoming not just influential but dominant.

This month, Blackstone has floated Celanese, a hastily rejigged German chemicals company, on the US equity market. There was some argy-bargy about initial overpricing but nevertheless Blackstone is pocketing $1.75bn in sale proceeds and special dividends, with much more to come from its remaining majority stake.