Patterson-UTI Energy Inc, a Delaware corporation was formed in 1978. It is a provider of contract services to the North American oil and natural gas industry. The Company owns and operates large fleets of land-based drilling rigs in the United States. As of December 31, 2012, it had a drilling fleet that consisted of 314 marketable land-based drilling rigs. The Company operates in three industry segments namely contract drilling services, pressure pumping services and oil and natural gas exploration and production. Its contract drilling operations are carried out in the continental United States, Alaska, and western and northern Canada. It provides pressure pumping services to oil and natural gas operators primarily in Texas and the Appalachian Basin. Pressure pumping services consist primarily of well stimulation and cementing for completion of new wells and remedial work on existing wells. The Company owns and invests in oil and natural gas assets as a non-operating working interest owner. Its oil and natural gas working interests are located primarily in Texas and New Mexico. The Company's customer base includes both major and independent oil and natural gas operators. It faces competition from companies which are providers of land-based drilling services which include Helmerich & Payne, Inc., Nabors Industries, Ltd., Pioneer Energy Services Corp. and Precision Drilling Corp. All of its operations and facilities are subject to numerous Federal, state, foreign, and local laws, rules and regulations related to various aspects of its business.