action. The court may even hear the action if the patentee has not filed a cease and desist letter. The standard for an actual controversy was most recently addressed by the Supreme Court in MedImmune, Inc. v. Genentech, Inc., 549 U.S. 118 (2007). But even if an actual controversy exists, the declaratory-judgment statute is permissive—a district court, in its discretion, may decline to hear a declaratory-judgment action. Usually the claimant is actually making, using, selling, offering to sell, or importing, or is prepared to actually make, use or sell, offer to sell or import an allegedly infringing device or method, and usually the patent owner has claimed that such activities by claimant will result in patent infringement. An express threat of litigation is not needed, nor is it a guarantee that jurisdiction will be granted. Some factors courts have considered in this analysis are whether a patent owner has asserted its rights against an alleged infringer in a royalty dispute, whether the owner has sued a customer of an alleged infringer, or whether an owner has made statements regarding its patents in trade magazines. If a patent owner does suggest that there is patent coverage of what an alleged infringer is doing or planning to do, the alleged infringer may bring suit. The alleged infringer, as the plaintiff in the suit, can choose the venue subject to constitutional restrictions and the state long-arm statute of the forum in question. The suit can be brought in any forum if the local federal district court can properly obtain personal jurisdiction over the alleged infringer. Defendants in infringement cases can ask for declaratory judgment as a counterclaim. A counterclaim of infringement is a compulsory counterclaim to a claim for declaratory judgment of non-infringement. If a patent owner fails to assert an infringement counterclaim in a declaratory-judgment non-infringement suit, the patent infringement claim will be deemed waived. See also Arrow declaration References External links 28 U.S.C. 2201-2 – Declaratory judgment Federal Rules of Civil Procedure, Rule 57 Judgment (law) Civil procedure Equity (law)