The court upheld a ruling from the lower U.S. District Court for Alaska. The appeals court said Shell had shown "a likelihood of success on the merits of its claim that Greenpeace USA would commit tortuous or illegal acts against Shell's arctic drilling operations in the absence of an injunction," reports energy news site Rigzone.
Shell charged that Greenpeace activists used illegal means to interfere with their arctic drilling campaign.
Greenpeace campaigners in 2010 boarded Shell's rig Harvey Explorer in the Gulf of Mexico. It was slated for later arctic work. In February 2012, the group employed similar tactics with the Noble Explorer drillship as it prepared to leave New Zealand for Alaskan waters.
Shell's drilling program in the Beaufort and Chukchi seas last year was hampered by equipment failures and weather-related delays. Its drillship Kulluk struck ground off the coast of Alaska in January.
U.S. Greenpeace Executive Director Phil Radford said Shell's decision to delay work offshore Alaska amounts to an admission that those echoing concerns about oil and natural gas exploration in arctic waters were right.
There was no public response Thursday from Greenpeace on the court ruling.