Raj Rajaratnam, the Sri Lankan-born founder of the $7 billion hedge fund Galleon Group, bought a 20 percent stake in broking firm Lanka Orix Securities Pvt.

Lanka Orix Leasing Company, which held 30 percent of the stock-broking firm, and Ishara Traders, which owned 40 percent, sold their stakes to Rajaratnam and other investors, said Tushan Wickramasighe, managing director at Lanka Orix Securities.