A peek inside billionaire Harold Hamm's closed divorce trial

Oil divorce war
Oil divorce war

The divorce of billionaire Harold Hamm has been filled with unusual arguments.

Hamm's wife, Sue Ann, says she has a right to divide his $17 billion fortune. Hamm, CEO and founder of energy giant Continental Resources, argues that his success and company are mainly the result of luck and factors beyond his control, so it shouldn't count as marital wealth.

Now, another strange wrinkle in the case has emerged—and it's one that some observers said could result in a new trial, or at least an appeal.

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Citing interviews with multiple people who had been at the Oklahoma trial, Reuters reported that Eric Eissenstat, general counsel, senior vice president, secretary and chief risk officer for Continental Resources, has been "one of the most important people in the courtroom." He reportedly interjected during proceedings, talked to the judge, and at one point stood in the jury box next to a witness, according to Reuters.

Harold Hamm and his wife Sue Ann Hamm, in April, 2012
Kevin Mazur | WireImage | Getty Images

In a statement, Continental told Reuters that Eissenstat's relationship with the judge is "professional and no different than the other individuals present in his courtroom."

The trial was largely closed to the public. Seymour J. Reisman, a veteran matrimonial and family law attorney not involved in the case, told CNBC: "It is mind boggling to learn that the general counsel of Continental Resources, the company founded and run by Mr. Hamm, was permitted to sit in the jury box and enter and exit the court as he pleased."

"The company attorney's behavior and the judge's decision to allow him to behave inappropriately all but guarantees that the verdict will be appealed and could be thrown out," Reisman said.

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There are also questions about how much shareholders are paying for Hamm's private dispute. Because Hamm founded and built the company, and his stake in it is the subject of the dispute, it's expected that Continental will incur some costs related to documents and subpoenas. Still, outside divorce attorneys say it's unusual for the corporate counsel to play such a large role during the divorce trial.

"If the attorney is there, he would normally be sitting in the spectator's area," Reisman said. "But if he's in the jury box or advising the CEO of the company in any way during the trial, then the shareholders shouldn't be paying for it."

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The trial ended in early October and the judge in the case, Special Judge Howard Haralson, is working through the testimony and documents before making a ruling in the coming weeks. Some say it could be the most expensive divorce in history.

Haralson didn't respond to Reuters when questioned. His bailiff told Reuters "the judge would not speak publicly about the case before ruling."

To read Reuters' full story, click here.