France ceded territorial claims to Newfoundland to Britain in the 1713 Treaty of Utrecht, but French fishermen retained rights to operate seasonal cod fisheries along a stretch of coastline known as the French Shore. The treaty was one of several laws formalizing the property regime based on the commons that emerged among European fishermen in the sixteenth and seventeenth centuries. Several demographic and geopolitical changes converged after the Seven Years’ War (1756–63) to raise the question of whether French fishing rights on the French Shore were exclusive or concurrent with British fishing rights on that coast. Treaty and customary law seemed at odds on this question, forcing fishermen, merchants, naval officers, and ministers to articulate what constituted property and how property should be conceived if an interimperial commons were to work. The conflicts that transpired highlighted how they answered these questions differently. Agents of the state tended to promote the commons while some British subjects tried to create a real property regime from below. Disputes over real property formation on the French Shore show another dimension of the early modern enclosure process, demonstrating both the role of the commons in empire and the challenges of resource management in an interimperial space.