A senior Maritime Affairs official in the Marshall Islands says the rig that exploded in the Gulf of Mexico met safety standards and was inspected regularly.
It has been suggested that the Marshalls be held responsible for the explosion, which killed 11 people and flooded the Gulf with crude oil, because the Deepwater Horizon rig was registered there.
The senior deputy commissioner of Maritime Affairs, Bill Gallagher, says the Marshalls is part of the investigation but the rig was owned by Transocean.
He says it was inspected regularly by the United States Coast Guard, Maritime Affairs and other agencies, and met international safety standards.
"The flag state has a responsibility to do inspections also, which we do," Mr Gallagher says.
"But irrespective of what flag you have, if you're operating under the US outer continental shelf, you are going to be regulated by the United States, the coastal states."
Mr Gallagher says Maritime Affairs officials will have the third of four meetings with investigators in Louisiana next month.