. Under 17 USC 505, a federal district court may, in its discretion, award attorney fees to the prevailing party. This decision holds that in exercising that discretion, the district court should give significant, but not necessarily controlling, weight to whether the losing party advanced a reasonable claim or defense. The Court rejects Kirtsaeng’s proposal that the court give weight to whether the case resolved a close and important legal question meaningfully clarifying copyright law. But the Court emphasizes that the reasonableness of a party’s claim or defense is only one factor and the court must take other circumstances into consideration such a party’s litigation misconduct or the need to deter repeated infringements or overaggressive assertion of copyright claims.