It is a legal maxim that patents, like any other intellectual property rights, are territorial rights. Patents are granted on a national basis and so patent holders seeking protection in multiple countries are invited to procure multiple national rights. Historically, courts, and most notably in the United States, have opted for a narrow understanding of the concept of territoriality of patents. This has more recently been reaffirmed by the United States Supreme Court in Deepsouth Packing Co. v. Laitram Corp, 406 U.S. 518 (1972) and Microsoft Corp. v. AT&T Corp, 550 U.S. 437 (2007) where the Court refused to extend the U.S. Patent Act extraterritorially based on the presumption that federal statutes, including patent statutes, shall not extend to acts occurring abroad. Importantly, if this was not the legal standard, then there would be a risk of encroaching upon the sovereignty of other states to regulate what could count as infringing activities in their respective territories. The traditional notion that patents are territorial rights is, however, under considerable stress. Just as commerce is becoming increasingly global, so do infringing activities coincide less neatly with national borders. Depending on the technical field, the subject-matter is also becoming increasingly prone to disseminate across borders. Because patent statutes differ between different jurisdictions, there is and will continue to be a tension between these economic and technological developments and the territorial limitation of patent rights. To illustrate this predicament, some courts in the United States have persisted, even if inconsistently, in refusing to find for infringement when infringing activities that fall under patent claims have been geographically divided. In NTP, Inc. v. Research in Motion, Ltd., 418 F.3d 1282 (Fed. Cir. 2005), the Federal Circuit made a distinction between system claims and method claims, and found that there was no infringement of the latter where not all steps were performed domestically. This outcome is akin to the approach taken earlier in Deepsouth, in that it presupposes that all constituent parts of the invention can and indeed must be localized to the country of protection. The argument seems to originate from what is more commonly known as the “all elements rule”, which makes it clear that for there to be direct patent infringement, an infringing product or service must include each and every element of the patent claim. But when that rule is enforced rigorously through a territorial lens in cross-border contexts, what is otherwise so basic and fundamental makes so little sense. It ignores that infringing parties can circumvent the exclusive patent rights by organizing the infringing activities, whether that is intentional or following the flow of modern business patterns, so that parts of them are completed in different countries. In contrast, courts in other countries such as Germany and the United Kingdom have considered more expansive readings of patent statutes and patent claims as a legal necessity to avoid legal loopholes for patent enforcement in cross-border contexts. In the German case Prepaid-Karten II, 2 U 51/08, the Court of Appeals of Düsseldorf found that there was direct infringement in Germany of a method claim, even if all steps but one were performed outside Germany. Instead of dissecting where each claim element was performed, the Court focused on whether there was nevertheless commercial intent to exercise the invention in Germany. In the United Kingdom, courts have instead adopted a claim-focused approach, where what counts as infringing use of an invention within the United Kingdom depends on a construction of what constitutes the “substance” of the invention. See Menashe Business Mercantile Ltd v. William Hill Org. Ltd, [2002] EWCA Civ 1702, and Research in Motion UK Ltd v. Motorola Inc, [2010] EWHC 118 (Pat). This is not too different from how the United States Court of Claims considered several decades earlier in Decca, Ltd. v. United States, 544 F.2d 1070 (Ct. Cl. 1976), that there was infringement in the United States where the invention was “controlled” by the defendant within the United States, where also the “patentees’ true contribution” was deemed to be located. Thus, while there is a growing trend in several jurisdictions towards engaging in what are more far-reaching practices of localizing infringements, these forms of extraterritorial application have been inconsistent. These tests have also remained largely unclear and unsubstantiated. For some inventions, such as problem inventions and combination inventions, it is not possible to attribute a particular essential part of the invention to a particular claim element. There is simply no single claim element to construe as the “substance” of the invention. Moreover, with patent infringement being a strict liability tort, there is no plausible legal basis in patent law for introducing a requirement that there must be commercial intent for there to be infringement, let alone in cross-border situations. The implications of this debate are far from hypothetical or theoretical, but very much real. Inventions that are susceptible to transnational practice, particularly in biotechnology, software, artificial intelligence and telecommunications, are becoming increasingly commonplace, yet it is at the same time becoming increasingly difficult for both right holders and users to predict in which jurisdictions these inventions are deemed to be carried out. With multiple jurisdictions implicated in the case of cross-border and divided patent conduct, and with different substantive settings, norms and interpretations, it is clear that finding common ground at best, or achieving clarity at least, is acute in avoiding a patent loophole. What is needed is a proper substantive framework, which links infringing use of the invention closer to its rightful technical lens, but while avoiding the dilemma of dissecting claim elements and not forgoing that it is necessary to balance competing sovereign interests. Whether conduct falls under a patent claim or not is a technical test, at the end of the day. This fundamental criteria for assessing patent infringement should not be abandoned merely because the conduct is now cross-border. Just as we examine when there is infringement from a technical standpoint, so should we evaluate where an infringement occurs from that same lens. This is certainly possible to do without dissecting claim elements, by instead focusing on where the technical contribution of the invention as a whole is achieved. This analysis is however still largely one-sided from a contacts point of view, as it is limited to contacts linked to the relevant country of protection, which is typically the forum. But sovereignty signifies not only the boundaries of a state’s own laws. The independence and equality of state sovereignty likewise denotes a duty to recognize the same territorial limits of other states. After defining the contacts to the relevant country of protection, it should therefore be deemed necessary to weigh these contacts with established contacts in other countries. The overwhelming purpose in this regard is to safeguard the efficacy of patent protection in cross-border cases when localizing the infringing conduct, while providing a reasonable degree of predictability and ensuring that sovereign, public and private interests are duly taken into account. With some effort to adopt a more uniform and balanced legal test, the patent loophole may indeed be closed across borders, without engaging in comprehensive and unfeasible harmonization and without sacrificing fundamental objectives in the process.