The Discoverer 534 was the sister ship of the famous world record breaker Discoverer Seven Seas. The Sonat Discovered class vessel was built in 1975 at Mitsui Osaka shipyard, Japan.
Upgraded in 1990 to a DP, deepwater drillship capable of operating in 6,000 ft of water. After the upgrade, the vessel commenced drilling in 3730 ft of water, followed by a well in 5900 ft of water during the first quarter of 1991. This was the world water depth record for a vessel with a 18-3/4 in. BOP stack and a 21 in. drilling riser. The Discoverer 534 operated continuously on DP since the upgrade, with excellent reliability and station keeping performance. The drillship set a new world water depth record of 7,500 ft.
In 1999 the Discoverer 534 drilled the Thunderhorse discovery well on Mississippi Canyon Block 778 in a water depth of 6,000 ft.
In 2007, a major life-enhancement and upgrade was performed at Singapore Sembawang shipyard to enable the rig to conduct more challenging operations offshore Pakistan and India.
The vessel was sold by Transocean in 2012 and stacked in Singapore.
Shortly after it was acquired by Houston based Helix Energy Solutions and renamed as Helix 534. The vessel was converted to an intervention vessel at Jurong Shipyard in Singapore and sailed to the Gulf of Mexico in 2013.
In December 2016 the Helix 534 was sold to a third party for $2.8 million after being stacked for more than a year in the Gulf of Mexico.