A preliminary injunction is appropriate if the moving party demonstrates either (1) a probability of success on the merits and a possibility of irreparable injury, or (2) serious questions going to the merits and the balance of hardships tipping sharply in his favor. Chalk v. United States Dist. Ct., 840 F.2d 701, 704 (9th Cir. 1988). These are not discrete tests, but are instead "outer reaches 'of a single continuum.' " Id. (citations omitted).
"The grant or denial of a motion for a preliminary injunction lies within the discretion of the district court, and its order will be reversed only if the court relied on an erroneous legal premise or otherwise abused its discretion." Id. An "abuse of discretion" occurs if the district court misapprehends the applicable legal issues or rests its conclusions on clearly erroneous findings of fact. Id.