AP Ackman: Bond insurers need another downgrade Wednesday June 11, 4:30 pm ET By Joe Bel Bruno, AP Business Writer Activist hedge fund manager Ackman says more downgrades are needed for MBIA, Ambac NEW YORK (AP) -- William Ackman, the billionaire activist hedge fund manager, said Wednesday that the recent downgrades of bond insurers and other financials might not have gone far enough. The founder of Pershing Square Capital Management, who is open about shorting bond insurers such as MBIA Inc., said rating agencies need to dig deeper into the companies to get a better idea of what is on...