Blackstone, the world's largest buy-out firm, is planning to list up to eight companies it owns and sell at least five others, marking a reversal of its pessimistic view of the global economy and financial markets.

Steve Schwarzman, Blackstone's founder, told investors in a letter sent on Friday: “We see the world changing once again. At least for private equity, the worst is behind the industry.”

Mr Schwarzman's stance is noteworthy because no other leading buy-out firm anticipated the economic downturn to the extent that Blackstone did, nor turned as bearish as early.

Blackstone was among the most active private equity buyers in 2005 and 2006 but grew cautious after leading the investment group that bought Freescale Semiconductor in September 2006.

As prices and debt levels for buy-out transactions continued to soar, Mr Schwarzman and Tony James, Blackstone's president, stayed largely on the sidelines the following year, committing money to only one of the 20 biggest deals. Blackstone also eschewed the diversification strategies of many competitors, such as the ill-fated foray by a Carlyle affiliate into complicated mortgage securities.

As recently as its August earnings call, Blackstone remained cautious, saying it did not expect to list or sell many of the companies in which it had invested. Because it held back, investors have received almost no cash proceeds from its private equity investments.

In his letter, Mr Schwarzman expressed some qualifications about the recovery, saying it was the product of fiscal stimulus and inventory rebuilding, both one-off events.

He made clear Blackstone was acting to capitalise on improved conditions. “We are seeing the beginning of realisations through strategic sales and public equity offers,” he said.