Cobalt International Energy Inc.'s (NYSE: CIE) James H. Painter, president of exploration and appraisal, has resigned, the Houston-based company said in regulatory filings on April 11.James H Painter Cobalt International Energy President Exploration Appraisal Resigns

Effective April 13, Tim Nicholson was appointed senior vice president of exploration and appraisal of Cobalt, the company said. Nicholson joined Cobalt in 2005 and has previously served as its vice president of exploration.

"Nicholson has been a key leader within the exploration team for the past decade and has been instrumental in the company’s exploration success in both West Africa and the Gulf of Mexico," Cobalt said in filings with the Securities and Exchange Commission (SEC).

Painter, whose resignation is effective April 30, had held his current position since January. He previously served as Cobalt's executive vice president of the Gulf of Mexico from the company's inception in 2005.

"The company extends its gratitude to Mr. Painter for his vision, leadership and many contributions and wishes him the best in his future endeavors," Cobalt said in SEC filings.

Painter has more than 35 years of experience in the oil and gas industry, according to Cobalt's website.