The Securities and Exchange Commission (SEC) on Thursday charged Citigroup Inc. with misleading investors about the company’s exposure to subprime mortgage-related assets.

The SEC also charged former CFO Gary Crittenden and Arthur Tildesley, Jr., formerly head of investor relations and currently the head of cross marketing at Citigroup, for their roles in causing the company to make the misleading statements in an SEC filing.

Citigroup and the two executives agreed to settle the SEC’s charges. Citi agreed to pay a $75 million penalty. Crittenden will pay $100,000, and Tildesley will pay $80,000.

The SEC alleges that in response to intense investor interest, Citigroup repeatedly made misleading statements in earnings calls and public filings about the extent of its holdings of assets backed by subprime mortgages.

According to a statement from the federal regulator, between July and mid-October 2007, Citigroup represented that subprime exposure in its investment banking unit was $13 billion or less, when in fact it was more than $50 billion.

“Even as late as fall 2007, as the mortgage market was rapidly deteriorating, Citigroup boasted of superior risk management skills in reducing its subprime exposure to approximately $13 billion,” Robert Khuzami, director of the SEC’s division of enforcement. “In fact, billions more in CDO [collateralized debt obligation] and other subprime exposure sat on its books undisclosed to investors.”

Scott W. Friestad, the enforcement division’s associate director, said Citigroup’s improper disclosures came at a critical time when investors were clamoring for details about Wall Street firms’ exposure to subprime securities.

“Instead of providing clear and accurate information to the market, Citigroup dropped the ball and made a bad situation worse,” Friestad said.

The SEC says Citigroup and the two executives charged consented to the settlement and fines without either admitting or denying the allegations.