ECR

Eclipse Resources Corporation

An independent oil and natural gas company that drilled for shale gas and oil in the Appalachian Basin, focused on Ohio's Utica Shale and the Marcellus Shale. Founded in 2011 in State College, Pennsylvania, by two brothers who had previously led another energy company, it made its name drilling "super laterals"—extra-long horizontal wells, one of which was touted as the longest onshore lateral ever drilled in the US at the time. In 2018 it merged with Blue Ridge Mountain Resources and rebranded as Montage Resources.