On July 14, 2006, Broadcom estimated it would have to subtract $750 million from earnings due to stock options irregularities. On September 8, 2006, the company announced the amount was at least $1.5 billion, "and could be substantially more." On December 18, 2006, the SEC opened a formal investigation of Broadcom's options practices. On January 24, 2007, Broadcom announced a restatement of its financial results from 1998 to 2005 to include a total of $2.24 billion-worth of expenses related to stock option-based compensation. The grants remained the subject of the formal inquiry by the SEC, and an informal inquiry by federal prosecutors.