Worlds First DP Class 3 Crew Boats

Transocean Ltd.  today announced that its ultra-deepwater semisubmersible rig Deepwater Horizon
recently drilled the deepest oil and gas well ever while working for BP and its
co-owners on the Tiber well in the U.S. Gulf of Mexico. Working with BP, the
Transocean crews on the Deepwater Horizon drilled the well to 35,050 vertical
depth and 35,055 feet measured depth (MD), or more than six miles, while
operating in 4,130 feet of water.

These achievements are the latest in Transocean’s history of world and other
records dating back to the 1950s. In 2005, the ultra-deepwater drillship
Discoverer Spirit set the record for the longest Gulf of Mexico oil and gas well
at 34,189 feet, MD. Most recently, the Transocean jackup GSF Rig 127 drilled the
industry’s longest extended-reach well in 2008 while working for Maersk Oil
Qatar AS at 40,320 feet MD with a 35,770-foot horizontal section. The well was
drilled offshore Qatar in 36 days and was incident-free.

Transocean also holds the current world water-depth record of operating in
10,011 feet of water set while working for Chevron in the U.S. Gulf of Mexico.

The Deepwater Horizon, placed into service in 2001, is a dynamically positioned
ultra-deepwater semisubmersible rig capable of working in water depths of up to
10,000 feet.