In 2002, Bill Ackman, a hedge fund manager, began research which concentrated on challenging MBIA's AAA rating, despite an ongoing probe of his trading by New York State and federal authorities. He was charged copying fees for copying 725,000 pages of statements regarding the financial services company, in his law firm's compliance with a subpoena. Ackman has called for a division between MBIA's bond insurers' structured finance business and their municipal bond insurance side, despite statements from the insurance companies that this would not be a viable option.