Sources close to Arnall confirmed to ABC News that she deposited the check.
Continental Resources CEO Hamm wrote a check dated Jan. 5 for $974,790,317.77 to settle divorce proceedings with his second wife. The legal proceedings have spanned more than two years.
Arnall, an attorney who was married to Hamm for more than 25 years and was a former executive at her husband's company, first rejected the check, Hamm's attorneys told media outlets Tuesday.
Hamm, who is worth about $8 billion according to Forbes, and Arnall had both appealed the November divorce judgment that awarded her about $1 billion. Lawyers for Arnall said the check compromised her appeal.
But Hamm's attorney says Arnall may have had a change of heart.
"She changed her mind apparently and made arrangements to open an account and deposit it," Hamm's attorney Craig Box told ABC News today. "Yesterday early afternoon we received a call that she presented the check at a bank in Oklahoma City that, for lack of better words, could accommodate the account. So they notified Morgan Stanley that the check was withdrawn. And later we received confirmation of it."
Box said Arnall and her attorney will have to legally withdraw her appeal.
"I’m happy for my client," Box said when asked for his reaction. "He’s a tremendous man and it’s been almost a three-year process. I’m just happy for him so he can go on with his life."