Standing to challenge patent validity depends not only on factual assessments about the risk of patent enforcement, but also on legal judgments about the limits of judicial power under Article III of the Constitution, the specific causes of action granted by Congress through its Article I powers, and the degree of Article II executive branch power exercised in enforcing patents. Consumer suits show the importance of the legislative power, for Congress has created two causes of action that differ dramatically in their ability to provide consumers with an effective means for challenging patents. Competitor suits show the importance of Article II considerations. Because patents are enforced largely by private parties, courts should be more willing to grant standing to plaintiffs challenging the validity of patents than to plaintiffs challenging the validity of statutes or regulations that can be enforced only by governmental actors in the executive branch.

John F. Duffy, Standing to Challenge Patents, Enforcement Risk, and Separation of Powers, 83 George Washington Law Review, 628–646 (2015).