The U.S. Supreme Court case Christianson et al. v. Colt Industries Operating Corp., in 1987, revolved around a patent dispute between two companies over the design of gas-operated automatic firearms. The plaintiffs, Christianson and his company IPSCO Inc., alleged that Colt Industries had falsely marked its M16 rifles as patented to deter competition from other manufacturers like IPSCO who were producing similar products without infringing on any patents held by Colt. Initially, the District Court dismissed the claim stating it lacked subject-matter jurisdiction because no patent issue was actually involved in this case since none of Colts' patents covered their M16 rifle's design or parts thereof which were allegedly being infringed upon by IPSCO. On appeal, however, both Seventh Circuit and Federal Circuit courts disagreed with each other about whether they had jurisdiction over this matter due to conflicting interpretations of federal law regarding appeals involving 'patent issues'. Ultimately though, when appealed to the U.S Supreme court for resolution on these contradictory rulings below; it ruled that once a court has assumed jurisdiction over a case under federal law (28 USC §1338), another appellate court cannot take away that jurisdiction merely because it would have concluded differently about presence/absence of an underlying 'patent issue'. Thus affirming Seventh circuit's original dismissal based on lack-of-subject-matter-jurisdiction grounds.

In the dissenting opinion for Christianson et al. v. Colt Industries Operating Corp., Justice Stevens argued that the majority's decision to allow federal courts jurisdiction over state law claims, based on their connection to patent law issues, was incorrect and inconsistent with precedent. He contended that this ruling would unnecessarily complicate matters by allowing parties to manipulate litigation strategies in order to secure a more favorable forum or delay proceedings indefinitely. Furthermore, he expressed concern about the potential for increased workload on federal courts due to an influx of cases involving peripheral patent law issues but primarily grounded in state laws. In his view, such cases should be handled at the state level unless they present substantial questions of federal patent law which are necessary for resolution of the case.