Just how big of a mistake remains to be seen, even after JPMorgan disclosed that losses at the unit have grown to $5.8 billion in total, clouding the bank's 2012 earnings. The nation's largest bank by assets said on Friday that it would restate first quarter earnings by $459 million, according to a filing with the Securities and Exchange Commission, as a result of a what it characterized as an attempt to hide losses at its CIO unit. The decision to restate earnings was made on Thursday, said chief financial officer Douglas Braunstein, on a media call. "The firm has recently discovered information that raises questions about the integrity of the trader marks and suggests that certain individuals may have been seeking to avoid showing the full amount of the losses in the portfolio during the first quarter," JPMorgan said in its restatement filing on Friday.