Billionaire investor Bill Ackman is planning to take his firm, Pershing Square Capital Management, public on the stock market while launching a new investment fund, which aims to raise billions from everyday investors and major financial institutions. The new fund,Pershing Square USA, will be a closed-end fund that sells a fixed number of shares in an initial public offering, or IPO, then allows them to trade like regular stocks on exchanges. The fund will raise at least $5 billion total, including $2.8 billion from a private placement. Shares start at $50 each, with a minimum buy of 100, and any investor will cost $5,000 to get on board. The money raised will go towards the firm's goal of making big money bets on public companies.