Under Art. 92 (United Convention on the Law of the Sea (UNCLOS), ships sailing the high seas are subject to the exclusive jurisdiction of their flag State. Despite being considered a pivotal rule in the international law of the sea, the scope of this provision is nonetheless still unclear: indeed, as Art. 92 does not characterise the term ‘jurisdiction’, it leaves open the question of whether it only encompasses enforcement jurisdiction or also prescriptive and adjudicative one. In the well-known ‘Lotus’ case, the Permanent Court of International Justice (PCIJ) ruled that exclusive flag-State jurisdiction only refers to enforcement jurisdiction. This understanding prevailed until two recent cases (M/V ‘Norstar’ and ‘Enrica Lexie’ Incident) ruled that States are prohibited from attaching legal consequences to the conduct of foreign ships and of the people on board altogether. Against this backdrop, the work discusses the extent of the exclusivity of flag-State jurisdiction over ships sailing the high seas. It contends that jurisdiction under Art. 92 UNCLOS only encompasses the faculty to impede or otherwise interfere with the actual movement of ships, hence the jurisdiction to enforce.