Warburg Pincus-backed Citizen Energy, an oil and natural gas exploration company, agreed to acquire Blue Mountain Midstream, an oil and gas producer, from Riviera Resources, a natural gas liquids company, for $111m. "This transaction is the culmination of our extensive review of strategic alternatives for Blue Mountain. Over the past twelve months, the company has spent extraordinary time and effort engaging with several counterparties in an effort to maximize the sale value of Blue Mountain. Given the challenging macro-environment, we are pleased with this result. Consistent with past decisions, we expect to find ways to use the proceeds to return capital to shareholders," David Rottino, Riviera President and CEO.