In Contentious Divorce Case, Multibillionaire’s Wife Asks Judge to Void Prenup

— -- The wife of multibillionaire hedge fund manager Ken Griffin is asking a judge to throw out the prenuptial agreement that she says was signed under duress. If her request is granted, it could lead to one of the biggest divorce settlements in America.

Griffin, 45, filed for divorce this summer from his wife of 11 years, claiming irreconcilable differences.

Anne Griffin, 43, told a judge Tuesday that she was forced to sign their prenuptial agreement and asked that it be scrapped.

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The Griffins were married in 2003 in a lavish ceremony held at the Palace of Versailles in France. They live in Chicago and have three children.

In court papers filed in Cook County, Ill., Anne Griffin says the couple “argued intensely” in the days before the wedding about their prenuptial agreement. She alleges that her then soon-to-be-husband became violent and asked her to go a psychologist, whom she says convinced her to sign the prenup. Anne Griffin said she signed the agreement three hours before the couple's rehearsal dinner.

She also alleges that her husband failed to disclose that he’d had a prior professional relationship with the psychologist who counseled her then.

In legal filings, Anne, once a successful money manager herself, says the prenup would leave her with 1 percent of her husband’s estimated $5 billion-plus fortune, or around $50 million.

“This could be one of the biggest divorces we’ve seen in this country,” Vikki Ziegler, a celebrity divorce attorney not involved with this case, told ABC News. “[Anne] Griffin could get up to half of Kenneth Griffin’s net worth, and that could be over two and a half billion dollars.”

Anne Griffin is asking the judge to set aside the prenup based on a number of things, Ziegler said.

“Number one: She was saying she was forced and coerced into signing the prenup agreement twenty-four hours before wedding. Number two: she is saying the document is unconscionable and should not be upheld. And the third … is that Anne didn’t have enough time to consider all the assets,” Ziegler said.

Ken Griffin's lawyers deny his wife’s allegations, characterizing them as salacious and untrue.

Ken Griffin’s attorney said in a statement that it was “sad that Anne continues to make inflammatory statements purely for her own gain, and in an effort to attract publicity to what should be a private matter.”

Ken Griffin is the founder of the Chicago-based Citadel LLC.

Nathan Vardi, associated editor at Forbes magazine, said Griffin is a notably prominent player in the business.

"He's as big as they come," Vardi told ABC News. "He’s the guy people in the financial industry want to be, and also the guy that they fear."