On August 13, 2008, the Federal Circuit held in Jacobsen v. Katzer, 535 F.3d 1373 (Fed. Cir. 2008) (Jacobsen I), that parties who distribute software under the terms of an open-source license may obtain copyright remedies, including a preliminary injunction, against defendants who breach the terms and conditions of their license. On January 5, 2009, on remand, the U.S. District Court for the Northern District of California denied for a second time the plaintiff's motion for a preliminary injunction to stop a defendant from violating the terms of an open-source license. Jacobsen v. Katzer, 609 F. Supp. 2d 925 (N.D. Cal. 2009) (Jacobsen II). In so doing, the district court rejected the prevailing rule in copyright cases that entitled plaintiffs to an automatic presumption of irreparable harm upon showing a reasonable likelihood of success on the merits.
The Jacobsen II court's interpretation of a higher standard of proof and the move by other courts away from the presumption of irreparable harm casts doubt on whether open-source plaintiffs can ever practically meet the preliminary injunction standard. Although economic considerations may exist in the open-source licensing context beyond that of traditional license royalties or lost profits, such damages are more difficult to prove. In practice and given the lack of available evidence, the further open-source plaintiffs deviate from a profit-based software model, the harder they will find it to obtain a preliminary injunction.