Transocean Ltd. is a Swiss offshore drilling company. It is the world's largest offshore drilling contractor based on revenue. The company has offices in 20 countries, including Canada, the United States, Norway, United Kingdom, India, Brazil, Singapore, Indonesia, and Malaysia.
The primary business of Transocean is contracts with other large companies in the oil and gas industry. In 2019, Royal Dutch Shell, Equinor and Chevron accounted for 26%, 21% and 17% of the company's revenues respectively.
In 2010, Transocean was found partially responsible (30% of total liability) for the Deepwater Horizon oil spill resulting from the explosion of its offshore drilling rig (which was named Deepwater Horizon) in the Gulf of Mexico.
The company's principle executive offices are located in Steinhausen, Switzerland.
Contents
History
Transocean was formed as a result of the merger of Southern Natural Gas Company, later Sonat, with many smaller drilling companies.
In 1953, the Birmingham, Alabama-based Southern Natural Gas Company created The Offshore Company after acquiring the joint drilling operation DeLong-McDermott from DeLong Engineering and J. Ray McDermott. In 1954, the company launched Rig 51, the first mobile jackup rig, in the Gulf of Mexico. In 1967, the Offshore Company went public. In 1978, SNG turned it into a wholly owned subsidiary. In 1982, it was changed to Sonat Offshore Drilling Inc., reflecting a change in its parent's name. William C. O'Malley, an executive at Sonat's headquarters in Birmingham, was named the company's first Chief Executive Officer in 1992. In 1993, Sonat spun off the majority of its ownership in the company. Sonat sold its remaining 40% stake in the company during a secondary public offering in late 1995.
In 1996, the company acquired Norwegian group Transocean ASA for US$1.5 billion. Transocean started in the 1970s as a whaling company and expanded through a series of mergers. The new company was called Transocean Offshore. The new company began building massive drilling operations with drills capable of going to 10,000 feet (as opposed to 3,000 feet at the time) and operating two drill operations on the same ship. Its first ship, Discoverer Enterprise, cost nearly US$430 million and was 834 ft (254 m). The Enterprise class drillship is the largest of the drilling ships.
In 1999, Transocean merged with Sedco Forex, the offshore drilling subsidiary of Schlumberger in a $3.2 billion stock transaction in which Schlumberger shareholders received shares of Transocean.
Sedco Forex had been formed from a merger of two drilling companies, the Southeastern Drilling Company (Sedco), founded in 1947 by Bill Clements and acquired by Schlumberger in 1985 for $1 billion and French drilling company Forages et Exploitations Pétrolières (Forex) founded in 1942 in German-occupied France for drilling in North Africa. Schlumberger first got a foothold in the company in 1959 and then assumed total control in 1964, and renamed it Forex Neptune Drilling Company.
In 2005, the company's Discoverer Spirit rig set a world record for the deepest offshore oil and gas well of 34,189 ft (10,421 m).
In 2007, the US Department of Justice and the Securities and Exchange Commission filed a case against Transocean, alleging violations of the Foreign Corrupt Practices Act. The case alleged that Transocean paid bribes through its freight forwarding agents to Nigerian customs officials. Transocean later admitted to approving the bribes and agreed to pay US$13,440,000 to settle the matter.
In 2007, the company merged with GlobalSantaFe Corporation in a transaction that created a company with an enterprise value of $53 billion. Shareholders of GlobalSantaFe Corporation received $15 billion of cash as well as stock in the new company for their shares. Robert E. Rose, who was non-executive chairman of GlobalSantaFe, was made Transocean's chairman. Rose had been chairman of Global Marine prior to its 2001 merger with Santa Fe International Corporation.
In September 2009, its Deepwater Horizon rig established a 35,050 ft (10,680 m) well, the deepest well in history – more than 5,000 feet deeper than its stated design specification.
In 2012, the company sold 38 shallow water rigs and narrowed its focus on high-specification deepwater rigs.
In October 2013, the company was added to the S&P 500 index, replacing Dell.
In February 2015, CEO Steven Newman stepped down following a $2.2 billion quarterly loss.
Effective on 30 March 2016, the company delisted its shares from the SIX Swiss Exchange, at which time its shares were removed from the Swiss Market Index.
In February 2025, Transocean's drilling rig, Mighty Barents, began drilling gas wells in one of the EU's largest gas project, Neptun Deep, with plans to begin gas production in 2027.
In April 2025, Keelan Adamson, former COO of Transocean, took over as CEO of the company.
Transocean sold four of its idle rigs to an undisclosed buyer in September 2025. Included in the sale was the Discoverer India, Discoverer Clear Leader, Discoverer Americas, and Deepwater Champion, all of which had been cold stacked for years prior to the sale.
In October 2025, Transocean extended two drilling rig contracts totaling $243 million with Petrobras and BP.
Acquisitions
In 2000, Transocean acquired R&B Falcon Corporation, owner of 115 drilling rigs, in a deal valued at $17.7 billion. With the acquisition, Transocean gained control of what at the time was the world's largest offshore operation. Among R&B Falcon's assets was the Deepwater Horizon.
In 2011, the company acquired Aker Drilling, which owned 4 harsh environment rigs used for drilling near Norway.
Effective on 30 January 2018, the company completed its acquisition of Songa Offshore. Later that year in December, the company acquired Ocean Rig for $2.7 billion.
Controversies
Accidents and incidents
Transocean was rated as a leader in its industry for many years. However, since the company's 2007 merger with GlobalSantaFe, Transocean's reputation has suffered considerably, according to EnergyPoint Research, an independent oil service industry rating firm. From 2004 to 2007, Transocean was the leader or near the top among deep-water drillers in "job quality" and "overall satisfaction." In 2008 and 2009, surveys ranked Transocean as last among deep-water drillers for "job quality" and next to last in "overall satisfaction." In 2008 and 2009, Transocean ranked first for in-house safety and environmental policies, and in the middle of the pack for perceived environmental and safety record. The Deepwater Horizon explosion and massive oil spill, starting in April 2010, further hurt its reputation. "Transocean is dominant, but the accident has definitely tarnished its reputation for worker safety and for being able to manage and deliver on extraordinarily complex deepwater projects," said Christopher Ruppel, an energy expert and managing director of capital markets at Execution Noble, an investment bank.
On 2 March 2002, a Scottish man was killed in an accident aboard the Transocean Leader drilling rig operated for BP, located about 138 kilometers (86 miles) west of Shetland, Scotland.
On 17 June 2003, one worker was killed, four others were hospitalised and 21 were evacuated after an explosion on a Transocean gas drilling rig in Galveston Bay, Texas.
On 24 August 2005, the UK Health and Safety Executive issued a notice to Transocean saying that, it had failed to maintain its "remote blowout preventor control panel … in an efficient state, efficient working order and in good repair." On 21 November 2005, Transocean was found to be in compliance for this matter.
On 12 April 2007, the Bourbon Dolphin supply boat sank off the coast of Scotland while servicing the Transocean Rather drilling rig, killing eight people. The Norwegian Ministry of Justice established a Commission of Inquiry to investigate the incident, and the commission's report found a series of "unfortunate circumstances" led to the accident "with many of them linked to Bourbon Offshore and Transocean."
In 2008, two Transocean workers were reportedly killed on the company's vessels.