A court official said Thursday the two companies have 30 days to cease operations. The official did not provide further details. She spoke on condition of anonymity because she was not authorized to speak to the press.
Transocean said in a statement that it is "vigorously pursuing the overturn or suspension of the preliminary injunction."
Chevron did not immediately reply to a request for comment.
The injunctions were served two weeks after Brazil's top appeals court upheld an order for the two companies to suspend their petroleum drilling and transportation operations.