	investor firms have pct of symbion symb a group of affiliated firms led by warburg pincus capital co l p a new york venture capital and investment partnership said it has uired shares of symbion inc or pct of the total outstanding in a filing with the securities and exchange commission the warburg pincus group said it bought the stake for investment purposes although the group said it is considering buying more shares of symbion it said it has no plans to seek control of the company reuter 
