Feb 27, 2023

February 27, 2023 HOUSTON–( BUSINESS WIRE )–RSI Holdings LLC, an affiliate of Post Oak Energy Capital, LP, acting in partnership with certain individual investors, has sold its equity interests in Refinery Specialties, Inc. to Imperative Chemical Partners LLC in an all-cash transaction. RSI, headquartered in Hempstead, Texas, is a vertically integrated chemicals provider and services firm focused on manufacturing and supplying proprietary and custom solutions to its customers across the major producing basins. Mickey Tucker and other members of the RSI management team founded the Company and commenced operations in 1989. In late 2012, Post Oak led a consortium of investors in acquiring a controlling interest in the Company through a recapitalization. Since this recapitalization, RSI, under the leadership of Curtis Bordelon and Garrett Tucker, has steadily built and focused its business organically through entry into new basins, expansion in existing basins and market share additions, capacity expansion and the addition of new products. This sale is the next logical progression for RSI and its growth trajectory as the industry further consolidates. This transaction has resulted in a successful outcome for all. About Post Oak Energy: Post Oak, which was established in 2006, is an energy-focused private investor based in Houston, Texas. Its management team has executive management experience and a broad network in the energy business as well as significant expertise in equity investments, operations, development, finance, acquisitions and divestitures. The firm pursues private investments primarily in the upstream sector of the oil and gas industry in North America and, to a lesser extent, in oilfield service and related infrastructure. Post Oak works in close partnership with operating management teams to build businesses, accelerate growth and enhance shareholder value. www.postoakenergy.com .