BY MARK MAREMONT AND JOANN S. LUBLIN

It's the $100 million payday that didn't happen.

Eugene Isenberg agreed to waive a $100 million termination payment triggered when Nabors Industries Ltd. replaced him as chief executive while keeping him on as chairman.

The agreement followed "ongoing discussions" between Mr. Isenberg and fellow directors over the payment, said Dennis Smith, a spokesman for the oil-drilling contractor. Mr. Isenberg "certainly didn't need the money," was planning to donate the funds to charity and decided "this was in the best interest of shareholders," Mr. Smith said.

Mr. Isenberg, 82 years old, didn't return a message seeking comment. Reached at their home ...