An amicus curiae or amicus brief is when someone who is not a party in a lawsuit offers information that bears on the case but that has not been solicited by any of the parties. It’s used mostly as a way to make sure that various issues that wouldn’t otherwise come up are heard in court, in hopes against an overly broad legal ruling that might have widespread repercussions. Amicus curiae means “friend of the court.”
Got all that? Good. Maybe now you can understand Apple’s issue with Google trying to issue an amicus brief urging the U.S. Federal Court of Appeals to overrule Apple’s request for a sales ban on Samsung devices. Friend of the court? More like co-defendant.