Transocean Ltd., together with its subsidiaries, provides offshore contract drilling services for oil and gas wells in Switzerland and internationally. The company contracts mobile offshore drilling rigs, related equipment, and work crews to drill oil and gas wells. It also operates a fleet of mobile offshore drilling units, consisting of ultra-deepwater floaters and harsh environment semisubmersibles. It serves integrated energy companies and their affiliates, government-owned or government-controlled energy companies, and other independent energy companies. Transocean Ltd. was founded in 1926 and is based in Zug, Switzerland.