US private equity group Blackstone is lining up a partial US stock market flotation. It is seeking to raise $4bn (£2bn), according to a filing yesterday with the Securities Exchange Commission

It said it would offer ‘limited partner interests’ as part of the initial public offering – its first move into the public arena for a company that has specialised in taking companies private. In February it undertook a $39bn (£20bn) take over of Equity Office Properties Trust.

Blackstone was founded with $400,000 (£200,000) in 1985 by Pete Peterson, a former White House aide and ex-chief executive of Lehman Brothers, and Stephen Schwarzman, a former Lehman Brothers mergers and acquisitions specialist.

The largest buy-out groups have considered the idea of going public for some time as a way of securing a permanent source of capital and allowing their ageing founders to cash in on the value of the firms they built. Peterson is 80 and Schwarzman is 60.

A recent McKinsey study for the Financial Times estimated that Blackstone would be worth around $60bn (£30bn), if it were to go public, less than its US rivals Kohlberg Kravis Roberts and Carlyle.