The lawsuits alleged that the bank's top executives, including Chief Executive Jamie Dimon, misled investors about the company's investment exposure and the potential risk of loss on those bets.
"These derivative bets went horribly wrong, resulting in billions of dollars in lost capital for the company and billions more in lost market capitalization for J.P. Morgan shareholders," one of the lawsuits said.
Last Thursday, the bank disclosed that it had suffered more than $2 billion in losses on complex bets tied to the value of corporate debt.
Mr. Dimon, on NBC's "Meet the Press" on Sunday, described the loss as a "terrible, egregious mistake." The bank announced Monday that its chief investment officer, whose office was responsible for overseeing the trades, will retire from the company.
One lawsuit, filed by Saratoga Advantage Trust on Tuesday, is seeking to represent a class of investors in J.P. Morgan stock between April 13 and May 10.
April 13 was the date of a conference call given by Mr. Dimon to discuss the company's first-quarter results. The Saratoga lawsuit alleges that Mr. Dimon and the company's chief financial officer, Douglas Braunstein, misrepresented the losses and potential risk to investors. Mr. Braunstein and Mr. Dimon are named as defendants in both lawsuits.
The other lawsuit, filed by James Baker, a J.P. Morgan investor, is a so-called derivative suit against the bank's top executives and board of directors. In a derivative lawsuit, shareholders typically seek to have any damages recovered returned to the company as opposed to being paid to individual shareholders.