Bloomberg reported that JPMorgan Chase’s efforts to hide trading losses, outlined in a Senate report yesterday, may ignite debate over whether the largest U.S. bank is too big to manage and ratchet up pressure on CEO Jamie Dimon to surrender his role as chairman.

Bloomberg said, according to the report, Dimon misled investors and dodged regulators as losses escalated on a “monstrous” derivatives bet.

Bloomberg notes that the bank “mischaracterized high-risk trading as hedging,” and withheld key information from its primary regulator, sometimes at Dimon’s behest, investigators found. Managers manipulated risk models and pressured traders to overvalue their positions in an effort to hide growing losses.

To read the entire Bloomberg story, click here.