Updated

A company run by the former CEO of American International Group Inc. is suing the government for $25 billion in damages over its taxpayer bailout of the big insurer.

Former AIG CEO Maurice "Hank" Greenberg's current company -- Starr International -- filed lawsuits Monday in two federal courts against the Treasury Department and the Federal Reserve Bank of New York. The suits accuse the government of taking valuable assets from AIG's shareholders without their consent or fair compensation, in exchange for the government's 80 percent stake in the company. The suit says the government's actions violate parts of the Fifth Amendment.

Much of the $182 billion in rescue money that AIG got from the government went to pay the New York-based firm's obligations to big banks.

Starr International was the largest shareholder in AIG. It is suing on behalf of AIG and the AIG shareholders and says the $25 billion or more in damages it wants represents the market value of the 563 million shares the government received, as of last Jan. 14.

"The government is not empowered to trample shareholder and property rights even in the midst of a financial emergency," Starr International says in the suits. It contends that the government discriminated in its action against AIG, by refusing to provide loans or loan guarantees or access to the Fed's discount borrowing window as it had to other financial institutions such as Citigroup Inc.

The AIG shareholders didn't agree "to the proposed taking of their property rights," the lawsuits say. They were filed against the government in the U.S. Court of Federal Claims in Washington and against the New York Fed in U.S. District Court in Manhattan.

Tim Massad, Treasury's assistant secretary for financial stability, said "It is important to remember that the government provided assistance to AIG -- and stopped it from collapsing -- in order to prevent a meltdown of the entire global financial system.

"Our actions were necessary, legal and constitutional," Massad said in a statement. "We are reviewing the lawsuit and expect to defend our actions vigorously."

The New York Fed said the allegations were groundless. "AIG's board of directors had an alternative choice to borrowing from the Federal Reserve, and that choice was bankruptcy," said spokesman Jack Gutt. "Bankruptcy would have left all AIG shareholders with worthless stock. The Federal Reserve's actions with regard to AIG helped to restore financial stability in the United States during a period of intense volatility and vulnerability in the U.S. economy."

AIG's latest repayment to the Treasury, $972 million on Oct. 31, brought its outstanding balance from the bailout down to about $68 billion. The government now owns 77 percent of AIG's common stock, having sold shares to reduce its stake.

Treasury has recouped $18 billion of the $68 billion it provided to AIG through the government's so-called Troubled Asset Relief Program. The rest of the money came from the New York Fed, to meet AIG's obligations to its Wall Street trading partners on financial instruments called credit default swaps. AIG has repaid all but $17.5 billion of those loans.

After the subprime mortgage bubble burst in 2007, the credit default swaps -- which insured against default of the securities tied to the mortgages -- collapsed. That pushed AIG to the brink. The company got an initial $85 billion infusion from the government on Sept. 16, 2008. The aid ultimately grew to $182 billion.

Some of the biggest beneficiaries of the rescue money also received federal bailout infusions themselves. They included Goldman Sachs Group, Bank of America Corp. and Citigroup.