Billionaire Ken Griffin heads to divorce court

The divorce trial of billionaire hedge-funder Kenneth Griffin and Anne Dias began Monday in a Chicago courtroom. And while Griffin is likely to avoid a major financial hit, it's probable the public proceedings will spark more unwanted financial and personal scrutiny of the Citadel CEO.

Griffin filed for divorce in July 2014 after 11 years of marriage, and the two have been battling in court filings over the past year. For now, the case is moving forward in Cook County Circuit Court; barring a settlement, it could drag on for months.

But divorce attorneys say a settlement — rather than a full trial — is the most likely outcome.

"As the old saying goes: 'They settle on the courthouse steps,'" said the divorce lawyer William Zabel, who is not involved in the case. "A lot of these cases settle just before trial because both sides want to push as much as they can."

In court filings, Griffin argues that the couple's prenuptial agreement signed before their marriage in 2003 is binding and valid. While the details of the document haven't been disclosed, Dias has said in filings that it would only give her about 1 percent of his fortune. Forbes estimates Griffin's net worth at $6.9 billion.

Griffin has countered that he has already given Dias $40 million as part of their martial settlement, and that he is paying full child support for their children.

He has also argued that Dias' request for $1 million a month is an effort to fund her "opulent lifestyle," which includes 24/7 use of a private jet and office and professional staff $60,000 a month.

Dias argues that the $1 million a month in child support simply reflects the family's spending levels when the couple was still married.

She has also said that she signed the prenup under duress and coercion, and that when she refused to sign the agreement just before their wedding, Griffin become "violent" and threw a bedpost at her. She also says she didn't have adequate time to review the document and Griffin's financials at the time.

Dias is seeking sole custody of their three young children and wants to move to New York, while Griffin is seeking to keep the kids in Chicago with joint custody.

The trial will take place in three parts — the first dealing with the prenup, the second focusing on child support and other financial matters and the third on custody and visitation.

Beyond the legal issues, however, the trial is likely to make headlines for the personal details and jaw-dropping dollar numbers that will emerge during testimony.

In filings, Dias said Griffin earned an average $100 million a month in 2014 , or around $68 million after taxes. Court filings show that Griffin's driver, pilots and personal staff have all been called as possible witnesses in the case. Personal assistants to the couple have also been called as possible witnesses.

"By any standard, the numbers in this case are very, very large," said the divorce lawyer Seymour Reisman, who is also not involved in the case. "I can't think of many cases at all with numbers like this. It's going to get a lot of attention."

As part of her effort to get custody, Dias may call witnesses to testify about Griffin's parenting skills and his personal life.

"The kids are her wedge," Zabel said. "She will want to argue that he's not been a very good father and hasn't spent much time with the kids." At the same time, Griffin may call witnesses to testify about Dias' role as a mother.

Since the trial is public, many of those details could come out during the proceedings.

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