British business information group Informa Plc said it had agreed to buy U.S.-based information services company Penton for 1.18 billion pounds to expand in the United States and grow its global exhibitions business. Informa will buy Penton from private equity firms MidOcean Partners and Wasserstein & Co, who will receive 1.11 billion pounds in cash and 76 million pounds in new Informa equity. The deal, part of Informa's growth acceleration plan, would help the company generate nearly half of its annual pro-forma revenues from the U.S. and make its global exhibitions division one of the three largest in the country,