A Practice Note discussing petitions for writs of mandamus filed at the US Court of Appeals for the Federal Circuit in patent litigation. This Note addresses the Federal Circuit's authority to issue writs of mandamus, the types of issues that the Federal Circuit frequently considers on mandamus review in patent litigation, pre-filing considerations, preparing and submitting mandamus petitions, responses, and replies in the Federal Circuit, and amicus curiae briefs and rehearing petitions in mandamus proceedings.