Pipeline operator Tallgrass Energy LP said on Nov. 25 that CEO David Dehaemers would step down immediately and named Bill Moler as his successor.

Moler, who was appointed as the company’s president and COO in March, has previously served as the executive vice president and COO of Tallgrass Energy.

Dehaemers, who came under fire from investors over sales talks with private equity firm Blackstone Group Inc., would be stepping down from the position immediately and retire as a member of the board on Dec. 31.

In August, Blackstone Infrastructure Partners, its partners and affiliates, who together already owned about a 44.2% stake in Tallgrass including 23.7 million Class A shares, made a non-binding preliminary proposal to buy Tallgrass’ remaining Class A shares at $19.50 per unit.

In October, Dehaemers had defended management provisions in the deal and blamed selling shareholders for a 23% stock price drop. He called it “patently false” that managers would get a higher price for their shares than retail investors in the company's limited partnership.