Transocean Ltd. had its "best year in safety performance" despite the explosion of its Deepwater Horizon rig that left 11 dead and oil gushing into the Gulf of Mexico, the world's largest offshore-rig company said in a securities filing Friday.

Accordingly, Transocean's executives received two-thirds of their target safety bonus. Safety accounts for 25% of the equation that determines the yearly cash bonuses, along with financial factors including new rig contracts.

The...