Anne Griffin Seeks to Void Prenuptial Agreement With Ken Griffin

When the billionaire hedge fund manager Kenneth C. Griffin moved to divorce his wife of 11 years this summer, his action took many by surprise.

Now his wife, Anne Dias Griffin, is having her say.

In documents filed in Cook County, Ill., on Tuesday, Ms. Griffin responded to her husband's divorce petition with a formal request for sole custody of their three children and for permission to move them to New York.

Anne Dias-Griffin, founder and managing partner of Aragon Global Management, left, and Ken Griffin, chief executive officer and founder of Citadel Advisors
Amanda Gordon | Bloomberg | Getty Images
Anne Dias-Griffin, founder and managing partner of Aragon Global Management, left, and Ken Griffin, chief executive officer and founder of Citadel Advisors

Perhaps more surprisingly, she also argued that a prenuptial agreement that the two signed in 2003 was actually done under duress and should be voided.

The two filings suggest that the breakup of the Griffins, one of Chicago's richest and most prominent power couples, will move from domestic dispute into public brawl. Hints of an acrimonious fight emerged soon after Mr. Griffin filed for divorce in late July, with Ms. Griffin contending that she had been blindsided by the move.

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On one side of the fight is Mr. Griffin, the founder of the hedge fund Citadel, whose net worth is an estimated $5.5 billion, according to Forbes. On the other is Ms. Griffin, a Harvard Business School graduate who had run her own investment firm but now largely focuses on raising the couple's children.

Yet despite the trappings of domestic calm, with the couple regularly making joint appearances at social events, matters were more complicated. In one of the filings on Tuesday, Ms. Griffin disclosed that her husband left their home in February 2012 and spent little time alone with the children. A person close to Mr. Griffin disputed that contention, arguing that he has attended school functions and taken them out.

In one filing from Tuesday, Ms. Griffin reiterated that she was on her way to the airport with the children for a vacation when she learned of the divorce petition. While she was gone, she added, Mr. Griffin had movers take out furniture and pieces of art from their home in Chicago.

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But the thrust of her legal response appears to center on an effort to overturn the prenuptial agreement, signed the day before the couple's lavish wedding in Versailles in July 2003. According to one of the filings, Mr. Griffin did not present a draft of the document until "shortly" before the wedding, catching her off guard.

He then disclosed his financial details on July 16 of that year, three days before the wedding. That day, she wrote in the filing, the couple had an intense argument during which Mr. Griffin broke a piece of furniture.

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To try to resolve the matter, Mr. Griffin suggested that the couple see a psychologist, but he did not disclose that he was already a patient of the individual, according to the filing. During the session on July 17, Ms. Griffin wrote, the psychologist recommended that she accede to Mr. Griffin's demands and sign the prenuptial agreement.

"As a result of Kenneth's actions as described above, Anne was unduly influenced by Kenneth and the psychologist under the guise of a counseling session with a neutral psychologist," she wrote in the filing. "Upon information and belief, Kenneth's purpose for arranging the therapy session with Anne and the psychologist was to convince Anne to sign his agreement."

The stakes for voiding the pact are high. According to Ms Griffin, if the agreement remains in place, she will be entitled to assets worth roughly 1 percent of her husband's net worth — about $50 million, if the Forbes estimate is correct.

A lawyer for Mr. Griffin said in a statement that the allegations by his wife were "salacious and simply untrue" and that the hedge fund magnate intended to protect his relationship with his children.

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"It is 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," the statement said.

—By Michael J. de la Merced, The New York Times

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