U.S. Well Services Holdings, LLC is the predecessor operating entity that combined with Matlin & Partners Acquisition Corporation (Nasdaq: MPAC), a blank-check company sponsored by MatlinPatterson Global Advisers LLC that completed its IPO in 2017. Focused on the energy sector, specifically electric-powered hydraulic fracturing services for oil and gas producers in North American unconventional basins, the company filed this 10-Q in August 2018 as part of the SEC registration process leading up to its de-SPAC transaction. The business combination closed in November 2018, with the resulting public company trading on Nasdaq under the ticker USWS. Sign up at SpacDesk for full filing histories, merger timelines, and deal analytics across thousands of SPAC transactions.