Maurice “Hank” Greenberg transferred $2.2 billion of American International Group shares to his wife four days before an accounting probe forced his ouster as chief executive officer of the insurer.

Mr. Greenberg, who ran AIG for almost 40 years before stepping down last month, made the gift of 41.4 million AIG shares to Corinne P. Greenberg on March 11, according to a regulatory filing made Tuesday. The shares represented 96% of the former CEO’s direct ownership stake in the New York-based company, the world’s largest insurer.

The shift may be an attempt to guard the couple’s wealth from lawsuits that might stem from the investigation by New York Attorney General Eliot Spitzer and the Securities and Exchange Commission, said former federal prosecutor Christopher Bebel. AIG has lost more than $52 billion of market value since the company disclosed accounting subpoenas on February 14.

“He probably did it on the advice of counsel as a precautionary measure,” said Mr. Bebel, who now practices law in Houston. The transfer may help shelter assets against civil suits and “put these assets beyond the reach of prosecutors,” Mr. Bebel said.

Mr. Greenberg, 79, hasn’t been charged or accused of any wrongdoing, and he didn’t disclose the reasons for the transfer. He stepped down as AIG’s chief executive officer on March 14 and as chairman two weeks later as regulators widened their probe.

A spokesman for Mr. Greenberg’s attorneys, Howard Opinsky, declined to comment; as did an AIG spokesman, Chris Winans; a spokesman for Mr. Spitzer, Darren Dopp; and an SEC spokesman, John Nester.

Mr. Spitzer told ABC television on April 10 that he may pursue a criminal or civil case against Mr. Greenberg, “a CEO who did not tell the public the truth,” he said. California Treasurer Philip Angelides said yesterday the state’s two pension funds should sue AIG “or any executives that are responsible” for the tumble in AIG’s share price, which cost the funds $400 million.

Transferring shares to his spouse may help protect the assets because Corinne Greenberg, 76, probably wasn’t a co-conspirator in any potential wrongdoing and isn’t a subject of the investigation, Mr. Bebel said.

Regulators and prosecutors are studying whether AIG and Mr. Greenberg used improper reinsurance transactions to inflate the insurer’s net worth and smooth earnings. The company said March 30 that improper accounting may have inflated its worth by $1.7 billion over 14 years.

Mr. Greenberg on Tuesday invoked his Fifth Amendment right to avoid self-incrimination on virtually all questions asked during an hour-long deposition with examiners for Mr. Spitzer and the SEC, said another spokesman for Mr. Greenberg’s attorneys, Paul Jensen.

Mr. Greenberg’s refusal to testify may hurt his defense in potential civil cases in the future, Mr. Bebel said.

The share transfer may ultimately fail to insulate the couple’s wealth, said a professor at Stanford Law School, Robert Weisberg.

Mr. Greenberg has already been named a defendant in at least 12 shareholder lawsuits in the wake of Mr. Spitzer’s probe of bid-rigging among brokers and insurers. Four AIG employees have pleaded guilty to Mr. Spitzer’s price-fixing charges in the past six months.

“If it’s transparently a gift to his wife, it presumably wouldn’t work,” Mr. Weisberg said. “The courts are going to say, ‘Phony baloney – we’ll simply take the stock from the wife same as we’d take it from the husband.'”

Mr. Greenberg may be forced to forfeit assets if he’s convicted of a financial crime, Mr. Weisberg said. Prosecutors can also freeze assets before a trial gets under way, he said.