Our History

Transocean traces its roots to onshore drilling operations, where T.S. "Stoney" Stoneman began his career as a draftsman and then a landman before joining the Danciger Oil & Refining Company of Fort Worth, Texas in 1926.

Mr. Stoneman bought the company's first drilling rig, paying for it with a personal check and putting it on his expense report. He would later play key leadership roles in pioneering offshore drilling with The Offshore Company.

While the first tentative steps to developing the marine drilling industry were being taken in the 1930s, drilling engineers were advancing onshore drilling methods and equipment.

While Danciger's T.S. Stoneman, shown in the photo above, continued his successful land career in the United States, Raymond Godet, an engineer who would later be a leader in another legacy company, Forex, was busy in France. Mr. Godet bought a German drilling rig in Paris and hooked it up to a boiler from a steam engine, enabling the rig to drill land wells at Saint Marcet.

Several legacy Transocean entities emerged in the 1940s when the following companies were formed. 

• 1942 - Forex was established in France
• 1946
  • Santa Fe Drilling Company was established. Joe Robinson, a Union Oil Company drilling superintendent, and 61 drilling department employees put up $250,000 of their own money and borrowed $600,000 to buy the business from Union Oil. Santa Fe began drilling wells onshore in California in 1947. In less than two years, the loan was paid in full.
  • The CUSS group was formed. This consortium of Continental Oil Company, Union Oil Company of California, Superior Oil Company and Shell Oil Company established the feasibility of drilling offshore. The CUSS group later evolved into Global Marine. 
• 1947 - Southeastern Drilling Company (Sedco) began operations. Led by Bill Clements, who would one day become a two-term Texas governor, Sedco began operations with two diesel-powered land rigs.

An important decade of innovation including the introduction of the world's first mobile jackup drilling rig and the first drillship ushered in new operations. 

• 1950 - Southern Production Co., a subsidiary of Southern National Gas, purchased Danciger and later began work to form The Offshore Company.
• 1953 - The Offshore Company was created to design and build Rig 51 (shown in photo), the world's first mobile jackup drilling rig.
• 1954 - The Offshore Company launched Rig 51. A new pneumatic jacking system raised the unit's legs at one drilling location so that the rig could be moved to the next where the legs were lowered to the seafloor. At that point, the rig's deck was elevated above the sea surface.
• 1955 - Sedco began operations with two, shallow-water semisubmersible barges in South Texas and built Rig 21, the first "post-type" swamp barge.
• 1956
  • Global Marine Drilling Company commissioned the CUSS I, the first drillship. This rig pioneered early versions of deepwater drilling methods and technology used by today’s offshore drilling fleet.
  • Santa Fe entered the offshore drilling business with a contract in Trinidad using a land rig adapted to a jackup barge and provided crews for a drillship offshore California.
• 1959 – Global Marine obtained its first multi-well drilling contract. Its crews drilled the first subsea production wells, which were completed with subsea trees and flow lines to the shore from Texaco’s “Jade” lease in about 300 feet of water offshore Santa Barbara, California.

Oil and gas discoveries continued to drive growing demand for offshore drilling services during the 1960s, requiring extensive capital investments for new rigs and equipment. 

• 1960 - Santa Fe became a public company with shares sold through the OTC Market. It expanded drilling operations from the U.S. to Australia and the Pacific.
• 1962 -
  • Glomar II (shown in photo) began operations as the first ship-shaped barge rig constructed as a newbuild unit. She was also the first self-propelled drillship to drill in Alaska's Cook Inlet and was later used in the Pacific in studies to evaluate mining of manganese nodules as part of the Deep Ocean Mining Project. The Cuss-class drillships names were changed this year from Cuss to Glomar.
  • Neptune Offshore was founded with capital from Forex and Languedocienne-Forenco.
• 1963 -
  • Santa Fe became listed on the New York Stock Exchange.
  • The world's first turret-moored drillship, Discoverer I, began operations.
  • The Offshore Company acquired International Drilling Co. Ltd. of London, marking the beginning of operations in the United Kingdom.
• 1964 -
  • Mr. Cap, a LeTourneau jackup rig charted by Global Marine, became the first rig to drill offshore The Netherlands in the North Sea.
  • Global Marine placed the first public offerings of debenture and common stock as a Delaware company, providing it independence from Union Oil.
• 1965 - The Offshore Company’s Hustler entered service as the first movable cantilevered drilling rig on a jackup barge.
• 1966 - Orion, became the first jackup designed for year-round operations in the North Sea.
• 1968 -
  • Santa Fe was renamed Santa Fe International Corporation and purchased its first jackup rig.
  • The Glomar Challenger began collecting seabed sediment cores around the world, a role that extended into 1983. Data collected allowed major advances in the theories of plate tectonics and continental drift.
  • Schlumberger acquired a majority interest in Forex.
• 1969 -
  • Offshore Mercury, began operations as the first self-propelled jackup.
  • Pentagone 81 was commissioned as the first semisubmersible rig built by Neptune of Forex, the French Petroleum Institute and the Hydrocarbon Support fund.

During this decade, Transocean legacy companies continued to pioneer dynamic positioning (DP) and other marine technology, enabling rigs to move between wells and stay on drilling locations using thrusters.

• 1971 - The Sedco 445 became the first modern self-propelled drillship. The rig later was called the Deepwater Navigator.
• 1973 - Global Marine designed and built the Hughes Glomar Explorer (shown in photo). The unit was contracted to the CIA for a secret mission, reported in the news media to be the recovery of a sunken Soviet submarine. It was retrofitted later as the Glomar Explorer and ultimately as the ultra-deepwater drillship GSF Explorer.
• 1977 - The Glomar Pacific drillship was placed into service, utilizing even more advanced DP technology along with the most up-to-date naval architecture and marine engineering.
• 1979 - The first DP semisubmersible, Sedco 709, made its debut.

Innovative drilling technology during this period led to new operations in offshore frontier areas, while mergers and acquisitions integrated some of the most experienced offshore drilling teams in the business.

• 1981 - The Kuwait Petroleum Corporation (KPC) acquired Santa Fe.
• 1982 - The Offshore Company became Sonat Offshore Drilling Inc.
• 1984 - Schlumberger purchased Sedco.
• 1985 -
  • Sedco and Forex Neptune were combined into the Sedco Forex drilling division of Schlumberger.
  • The world’s initial fourth-generation semisubmersible rig, Polar Pioneer (shown in photo), made its debut in Norway.
• 1986 – The Transocean Arctic in Norway became the first rig to drill year-round in the Barents Sea.
• 1987 -
  • Santa Fe purchased the first Monarch-Class heavy-duty, harsh-environment jackup, the Monarch.
  • Sonat Offshore Drilling, Inc. acquired the offshore drilling fleet of Dixilyn-Field (a PanHandle Eastern Company.)

Transocean's legacy companies achieved milestones that included the introduction of the latest generations of drilling rigs, a major safety achievement and integration through various transactions.

• 1993 - In May, Sonat, Inc. spun-off Sonat Offshore Drilling Inc., at which time Sonat Offshore Drilling Inc. (RIG) became its own entity and began trading on the New York Stock Exchange.
• 1996 -
  • In September, Sonat Offshore Deepwater Drilling Inc. acquired Transocean ASA. At this time the company name was changed to Transocean Offshore Deepwater Drilling Inc. and the logo was changed.
  • In December, Falcon Drilling Company became a publicly-traded company.
  • Santa Fe celebrated its 50th anniversary.
  • The Transocean Leader became the world’s first fourth-generation semisubmersible capable of year-round operations west of the Shetland Islands in more than 4,000 feet of water.
• 1997 -
  • In June, KPC divested 40 million Santa Fe shares and Santa Fe began trading on the New York Stock Exchange under the symbol "SDC."
  • In December, Reading & Bates and Falcon Drilling merged to become R&B Falcon Drilling.
• 1998 -
  • In December, R&B Falcon acquired Cliffs Drilling Company.
  • From March 1998 to February 1999, Global Marine’s entire nine-rig Gulf of Mexico jackup fleet recorded zero lost-time accidents, setting an industry first, reflecting the company’s ongoing commitment to safety.
• 1999 -
  • The Discoverer Enterprise (shown in photo) became the first ultra-deepwater, dual-activity drillship, the first of many rigs worldwide that today utilize Transocean’s patented dual-activity technology.
  • Schlumberger spun off Sedco Forex, which merged with Transocean Offshore Inc. to become the world’s largest offshore drilling contractor: Transocean Sedco Forex.

Three of the largest mergers in the company's history occurred in the 2000s. The company's ultra-deepwater and harsh environment floaters also made their mark with a string of world records.

• 2001 - Transocean Sedco Forex Inc. and R&B Falcon Corporation combined to form the world's largest offshore drilling contractor.
• 2001 - Global Marine and Santa Fe International merged to become GlobalSantaFe Corporation, the second largest drilling contractor.
• 2007 - Transocean and GlobalSantaFe merged as the world's largest offshore drilling contractor.

In addition, the company's ultra-deepwater drilling rigs made their mark in the 2000s with a string of world records, including:

• 2001 -
  • Discoverer Spirit – 7,209 feet of water, subsea completion record.
  • Deepwater Expedition – 9,144 feet, water depth record.
  • Deepwater Millennium – 9,200 feet, water depth record.
  • Discoverer Spirit – 9,687 feet, water depth record.
  • Discoverer Spirit – 9,727 feet, water depth record.
• 2003 -
  • Deepwater Nautilus – 7,570 feet of water, subsea completion record.
  • Polar Pioneer – 23,000 feet horizontal well record.
  • Discoverer Deep Seas (shown in photo) – 10,011 feet, water depth.
• 2004 -
  • Deepwater Nautilus – 8,951 feet, water depth, record for a moored rig.
• 2005 -
  • Deepwater Nautilus – 32,613 feet, true vertical depth, deepest offshore oil and gas well record.
  • Deepwater Spirit – 34,189 feet, measured depth, deepest offshore oil and gas well record.
• 2006 -
  • Deepwater Millennium – 9,000 feet of water, subsea completion record.
• 2009 -
  • Deepwater Horizon – 35,050 feet, vertical depth record and 35,055 feet, measured depth, deepest offshore oil and gas well record.

During the current decade, Transocean has continued to set world deepwater drilling records while upgrading our high-specification fleet.

• 2010 - A reminder of the over-arching importance of safety: the Macondo tragedy brought the loss of 11 crewmembers on the Deepwater Horizon on April 20 in the U.S. Gulf of Mexico. We will never forget our lost colleagues.
• 2011
  • The Dhirubhai Deepwater KG2 set the world water-depth record at 10,194 feet of water (3,107 meters) while working for Reliance in India.
  • In October, Transocean acquired Aker Drilling ASA
• 2012
  • Transocean announced plans to construct four, high-specification, ultra-deepwater drillships, backed by drilling contracts for the four rigs, each with a 10-year term. The 40 rig years represented the largest contracted period signed at one time in the history of the industry. The new drillships, two of which began operations in 2016, provide the most advanced offshore drilling technology available.
  • The company closed on the sale of 38 shallow-water drilling rigs to Shelf Drilling Holdings Ltd., further repositioning the company as a more focused operator of high-specification drilling rigs.
• 2013 - In July, India was the scene of another world record as the Dhirubhai Deepwater KG1 ultra-deepwater drillship (shown in photo) set the world water-depth record at 10,411 feet (3,174 meters) off the East Coast of the country while working for ONGC. That mark surpassed the prior record of 10,385 feet (3,165 meters) of water also achieved by the KG1 in February 2013.
• 2018
  • In May, Transocean Ltd. acquired Songa Offshore SE. The acquisition added seven floaters, four of which were high specification harsh environment.
  • In December, Transocean Ltd. acquired Ocean Rig UDW. The acquisition added 11 floaters, including four 7^th gen UDW drillships.
• 2019 - In October, Transocean Ltd. successfully deployed the world's first hybrid energy storage system aboard a floating unit, the Transocean Spitsbergen.