The dynamically positioned unit, idled since June, was hired by the Japanese player for more than two years at a variable dayrate ranging between the low $150,000s and low $210,000s depending on the work scope.

The Ensco 8505 will start work in December 2015 following shipyard time to install the mooring option. The deal runs through January 2018.

The rig player said it had also installed the technology on its semi-submersible Ensco 8503 for a contract with Stone Energy to offer "significant drilling efficiency and flexibility," the company said.

Analysts