Carrizo Oil & Gas, Inc. is an energy company. The Company is engaged in the exploration, development and production of oil and gas from resource plays located in the United States. Its operations are focused in proven, producing oil and gas plays in the Eagle Ford Shale in South Texas, the Delaware Basin in West Texas, the Utica Shale in Ohio, the Niobrara Formation in Colorado, and the Marcellus Shale in Pennsylvania. As of December 31, 2016, the Company's proved reserves of 200 million barrels of oil equivalent (MMBoe) were 64% crude oil, 12% natural gas liquids (NGLs) and 24% natural gas. As of December 31, 2016, it operated approximately 94% of the wells in Eagle Ford in which it held an interest. As of December 31, 2016, it held an average interest of approximately 85% in these operated wells. As of December 31, 2016, it owned leases covering approximately 309,200 gross (179,179 net) acres in the Eagle Ford, Niobrara, Utica and the Delaware Basin areas.