blowout preventer

BP said Friday that the Deepwater Horizon rig's blowout preventer, which failed to prevent oil from the Macondo well from flowing into the Gulf of Mexico, has been removed from atop the well.

Though BP has taken the brunt of the blame for the Gulf oil spill, the Deepwater Horizon rig was owned by Transocean, and as investigators delve deeper into what happened on April 20, they're focusing more on Transocean's maintenance practices.

BP has been ordered to retrieve the section of pipe that has the blowout preventer, the part that failed and helped to cause the explosion that wrecked the Deepwater Horizon rig, which of course triggered the largest oil leak in U.S. history.