Sentinel Energy Services Inc. (Nasdaq: STNL) was a special purpose acquisition company that completed its initial public offering in 2017, targeting acquisition opportunities in the energy and oilfield services industry. The vehicle was sponsored by Sentinel Energy Services Holdings LLC. Sentinel completed its business combination with Rockwater Energy Solutions, Inc., a provider of water management and chemical technologies to oil and gas producers, converting the blank check company into an operating oilfield services firm. The quarterly report filed in May 2018 reflects the company's post-combination operating status in the energy services sector. For complete SPAC filing history, sponsor profiles, and deal analytics on Sentinel and the broader market, create a free account at SpacDesk.