Allseas Group S.A. is a Swiss-based offshore contractor specialising in pipelay, heavy lift and subsea construction.[2] The company, founded in 1985 by owner and president Edward Heerema, employs 4,000 people and operates worldwide.

Industryoffshore pipelaying
undersea construction
FounderEdward Heerema
Number of employees


Allseas is an international offshore contractor specialising in the execution of large and complex projects, covering pipeline installation, platform installation and removal, and the installation of subsea infrastructure. The company provides support to clients already in the conceptual design stage and offer services for project management, engineering, fabrication, procurement, installation and commissioning.

The Allseas Group is headquartered in Châtel-Saint-Denis, Switzerland. Allseas Engineering B.V. with offices in Delft, Eindhoven and Enschede, the Netherlands, provides project management and engineering services to the group. The company also operates project and engineering offices out of Australia, Brazil and the USA.[3]

Allseas operates a versatile fleet of specialised heavy-lift, pipelay and subsea installation vessels designed and developed in-house. The company has installed over 20,000 km of subsea pipeline worldwide using S-lay technology, with diameters ranging from 2” to 48”.[4] Allseas’ launched its first vessel Lorelay, the world's first pipelay vessel to operate on full dynamic positioning, in 1986.[5]

In 1998, Allseas added the 300-metre (980 ft) Solitaire to its fleet.[6] The vessel has a pipe carrying capacity of 22,000 t and has achieved pipelay speeds in excess of 9 kilometres per day (5.6 mi/d). In 2006, while working on the Atwater Valley and Independence Trail projects in the Gulf of Mexico, Solitaire set new depth records, laying 10-inch pipeline in 2775 m (9100 ft) water depth and 24-inch pipeline in 2550 m (8370 ft) water depth.[7]

Pioneering Spirit (Aug 2016)

Allseas’ Pioneering Spirit is the world's largest construction vessel, designed for the single-lift installation and removal of large oil and gas platforms and the installation of record-weight pipelines.

Designed entirely in-house, the 382 m long, 124 m wide vessel can lift platform topsides up to 48,000 t and steel jackets up to 20,000 t.[8] The vessel is also equipped with state-of-the-art pipelay equipment, and can install the heaviest offshore pipelines in waters more than 4 km deep.

Pioneering Spirit set a new offshore lift record with the single-lift removal of Shell’s 24,200 t Brent Delta topsides in April 2017.[9] For its first commercial job, the vessel removed the 13,500 t Yme mobile offshore production unit from Norwegian waters for Repsol in August 2016.[10] Pioneering Spirit’s started its first pipelay job, installation of the offshore section of the TurkStream pipeline in the Black Sea, in June 2017.[11]

Allseas has committed to building an even larger version of the same design, Amazing Grace, which is scheduled to be delivered in 2022.[12]


Allseas was founded in January 1985 by Edward Heerema, son of the late Pieter Schelte Heerema, founder of the Dutch offshore construction and installation company Heerema Marine Contractors. Offices subsequently opened in The Hague (the Netherlands) and Châtel-Saint-Denis (Switzerland).

The company spent its early days developing the concept of dynamically positioned (DP) subsea pipelay. Allseas acquired the former bulk carrier “Natalie Bolten” in 1985 and converted it for DP pipelay at the Boele shipyard in Bolnes, the Netherlands. The vessel was christened Lorelay in Rotterdam on 26 April 1986.[13] Lorelay immediately entered service and successfully executed her first pipelay contract, the 8-inch, 1.8-km Helder A-B pipeline, for Unocal in the Dutch sector of the North Sea.

In 1987, the company declared its intention to build a vessel capable of lifting entire offshore platforms. The initial idea featured two rigidly connected, self-propelled supertankers, with a large slot at the bows to install platform topsides in one piece.[14]

During the late 1980s and early 1990s, the company established itself a major player in the North Sea and Gulf of Mexico. In 1992, the company acquired the former bulkhead carrier “Trenchwood” for conversion to Solitaire, the world’s largest pipelay vessel. Allseas awarded the conversion contract to Sembawang Shipyards in Singapore on a lump sum basis; however, due to ongoing problems the contract was terminated in 1995. The ship was subsequently converted at the Swan Hunter yard on Tyneside, England.[15] Solitaire laid her first pipe on Statoil’s Europipe project in 1999.[16] Allseas and Sembcorp reached a settlement for the Solitaire arbitration in 2006.[17]

Allseas added the shallow water pipelay and construction barge Tog Mor to its fleet in 2002. Solitaire’s S-lay capacity was increased to a holding force of 1,050 t in 2005, enabling her to lay the heaviest pipelines in unprecedented water depths.[18] The same year Allseas launched the dynamically positioned support vessel Calamity Jane. The 225 m long dynamically positioned pipelay vessel Audacia became operational two years later.[19]


In 2007 Allseas announced plans to build “Pieter Schelte”, a twin-hulled platform installation / decommissioning and pipelay vessel, named after the offshore pioneer Pieter Schelte Heerema, father of Allseas’ owner and founder Edward Heerema. At 382 m long and 124 m wide the vessel would be the largest ever built.

However, the original name created a controversy due to Pieter Schelte Heerema's service in the Waffen-SS during World War II.[20] After the war, Pieter Schelte Heerema was arrested and sentenced to jail for three years for his ties with the Nazi war effort, according to the Dutch National Institute for War Documentation.

The choice to name the ship after a Nazi SS member provoked an outcry from some politicians and Jewish groups around the world.[21] The Dutch government gave Allseas' Netherlands subsidiary a $1 million tax break for its part in designing the ship, which added to the controversy. In February 2015, Allseas stated that the name would change to "Pioneering Spirit".[22]

Victims of £73 m fraud
A criminal trial in the UK in 2016 revealed that Allseas were victims of a £73 m fraud. In 2011, they invested £73 m with investors led by Luis Nobre claiming to have links to the Vatican and Spanish nobility.[23][24]


In April 2016 Edward Heerema was made a Fellow Chartered Engineer by the Royal Netherlands Society of Engineers (KIVI) for his pioneering and innovative contributions to the offshore and marine industry.[25] It is the first time that this title has been awarded in the Netherlands.


  1. ^ Allseas website: About company, visited 21 December, 2019
  2. ^ "Allseas company".
  3. ^ "Allseas offices and yards".
  4. ^ "Pipeline installation".
  5. ^ "Converted DP Lorelay to install deepwater lines". Offshore Magazine. 1 January 1996.
  6. ^ "Major deepwater pipelay vessel starts work in North Sea".
  7. ^ "World's deepest floating production facility nears completion".
  8. ^ "World's largest ship so big it can lift an OIL RIG takes to the seas".
  9. ^ "Pioneering Spirit sets lifting record with Shell Brent Delta topsides removal" (PDF).
  10. ^ "Pioneering Spirit completes maiden heavy lift project" (PDF).
  11. ^ "TurkStream project".
  12. ^ "Allseas to build a single lift vessel larger than Pieter Schelte" (PDF).
  13. ^ "Swan revival means 1,200 jobs".
  14. ^ "Major deepwater pipelay vessel starts work in North Sea".
  15. ^ "SembCorp and Allseas reach full and final settlement for Solitaire arbitration" (PDF).
  16. ^ "Solitaire undergoes preparatory re-vamp as GoM developments head deeper".
  17. ^ "Audacia asset for summer 2007 launch".
  18. ^ "Allseas to change the name of the vessel Pieter Schelte" (PDF).
  19. ^ "Dutch outcry over naming giant ship after Nazi".
  20. ^ "New name for Allseas' single-lift vessel" (PDF).
  21. ^ "Dutch outcry over naming giant ship after Nazi".
  22. ^ "New name for Allseas' single-lift vessel" (PDF).
  23. ^ "City trader posed as a multi-millionaire with links to the Vatican in £73m fraud".
  24. ^ "Conman faces jail for posing as the Pope's banker in £73m fraud".
  25. ^ "Edward Heerema geïnstalleerd als Fellow Chartered Engineer" (PDF).