Associated Companies

Ownership in vessel owning companies and technology based companies that provide services on a global basis

Siem Consub SA

"...offshore services and engineering of systems for integration..."

The Company’s subsidiary Siem Consub SA in Brazil is an owner and operator of supply vessels and crew boats in the Brazilian market. Siem Consub’s head office is located in Rio de Janeiro in addition to bases located along the Brazilian coast. With more than 26 years of experience in Brazil, Siem Consub is focused on offshore support operations, submarine cable maintenance and installation, engineering and systems integration for the defence market.

Siem Consub undertakes projects that comprise underwater and naval technology, high quality resources and qualified professionals. Unique solutions have been implemented but each new project brings new challenges to overcome. 



Siem WIS AS 

" that will enable safer and more efficient drilling services..."

Siem WIS AS is 60% owned by Siem Offshore, and develops technology and solutions for managed pressure drilling and increased oil recovery services.

Subject to a successful development, the products will enable safer and more efficient
drilling and well maintenance services, including riser-less subsea intervention services from vessels.

Siem WIS has obtained patent award for the main products under development, including the first product called the CircSub – a device to be installed on the drill floor, which will enable constant circulation of mud during drill pipe connections.

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Siem Offshore Contractors (SOC)

Siem Offshore Contractors (SOC) is an experienced submarine cable and umbilical installation, repair and maintenance contractor serving the worldwide offshore oil and gas as well as renewable energy industries. 

SOC, a German company with its head office situated in the City of Leer, was formed in 2003. SOC has gained great experience in providing its service to the demanding worldwide offshore oil and gas industry, meeting the highest industry standards for quality, health, safety and environmental protection.

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