An investor group co-chaired by two former Securities and Exchange Commission chairmen has added its voice to those calling for private equity firms and hedge funds to register with the market watchdog, just as the US Treasury steps up its efforts to bring more transparency to the country's alternatives industry.

A report released by the Investors' Working Group, presented yesterday by former SEC chairmen William Donaldson and Arthur Levitt, supported the registration of all investment managers of funds, including hedge funds and private equity funds.