How much time and money Continental has spent so far on its CEO's divorce case isn't clear, however.
A review of Securities and Exchange Commission filings shows the firm has not disclosed any such costs to shareholders.
Continental did not respond to questions for this article. The company hasn't said if Hamm will reimburse it for the costs incurred. Hamm's lawyer, Craig Box, didn't respond to requests for comment.
Raising the stakes
Hamm's appeal "raises the stakes for his ex-wife," said Carolyn Thompson, an Oklahoma family law specialist. As Arnall presses Hamm for billions more, the oilman will try to convince the state's high court that what he owes her "should be reduced or eliminated," Thompson said.
Arnall was awarded a total of about $1 billion, in cash and assets, to be paid over a period of years. In his appeal, Hamm is contesting most of that award, including the court's order that he split with Arnall $1.4 billion derived from the rise in his Continental shareholdings. He also lists 26 other investments or properties he says were wrongly split up as marital assets. These include the couple's former Oklahoma City home and a $17 million California ranch, both awarded to Arnall.
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Hamm's appeal comes after the value of his Continental shares has fallen by more than half, to $9.3 billion, down from as much as $19 billion during the trial in August.
Continental's market capitalization eroded amid a recent plunge in oil prices, which now trade near five-year lows of $57 a barrel. In response, Continental plans to sharply cut spending next year.
Hamm founded Continental in 1967. When he and Arnall wed in 1988, the company was worth less than $50 million, filings show.
A month after the November 10 divorce ruling, Hamm asked the court to consider new evidence: a chart showing that Continental shares dropped 22 percent as oil prices fell 16.5 percent earlier this month.
"The dramatic drop in oil price post-trial and the corresponding drop in the CLR stock price demonstrate the overriding impact of the oil price on the value of the stock," Hamm, 69, said in a court filing dated December 16.
Hamm's request is unusual, said family law specialist Thompson. In her view, she said, the courts should only consider evidence admitted during the trial, which ended in October.
Arnall, 58, believes she was short-changed when the court failed to take account of both spouses' contributions to Continental, according to a person familiar with her case.
As an attorney for the company in the 1980s and 1990s, Arnall was part of Continental's successful lawsuits against a string of industry competitors. The millions it won were reinvested in drilling. Between 1996 and 2008, she formed and often managed Continental's profitable oil and gas marketing divisions, the person said.