Trio Petroleum Corp.’s co-founder and former board member Robin Ross has rejoined the California E&P’s board of directors, the company announced June 20.

Effective June 17, Ross is now chairman of the board. Other co-founder and current chairman Stan Eschner is stepping into the vice chairman role following former CEO Frank Ingriselli’s resignation as vice chairman and director.

“We are pleased to welcome Robin back to the board of Trio and have him assume this important leadership role with the company,” said Michael Peterson, CEO of Trio, in the company’s announcement of the changes. “His breadth of experience in finance, merchant banking and strategic development of emerging companies will add another tremendous resource for Trio and all of its stakeholders.”

Peterson continued, thanking Ingriselli’s contributions to the company, “from helping to form the company, leading our successful initial public offering and ultimately successfully launching Trio on the NYSE American. We wish Frank all of the continued success in his future endeavors.”