Development Driller III is a fifth generation, Vanuatu-flagged dynamic positioning semi-submersible ultra-deepwater drilling rig owned by Transocean and operated under lease agreements by various petroleum exploration and production companies worldwide.

The vessel is capable of drilling in water depths up to 7,500 feet (2,300 m) with drilling depth of 35,000 feet (11,000 m), upgradeable to 37,500 feet (11,400 m).

[3] On 2 May 2010, Development Driller III started drilling a relief well on Macondo Prospect to stop massive oil spill caused by the explosion and subsequent loss of the Deepwater Horizon.

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