State Silence and Territorial Title and Boundaries

This chapter discusses the circumstances where silence contributes to the formation of territorial titles. Three scenarios contemplate silence: when territorial titles are interpreted according to subsequent practice; when effectivités are performed by State A contrary to a territorial title held by State B; and when effectivités of States A and B are opposed to each other. Silence must meet certain requirements to be relevant: State A must put forward a consistent claim, which must be implemented in the disputed territory and come to the knowledge of State B. Once the claim is known, State B is under an obligation to react. Failing an appropriate reaction—such as a protest—silence will lead to the transfer of the title on the disputed territory. Notwithstanding the shortcomings of courts’ analysis regarding the legal value of silence, case law is compatible with a line of reasoning where silence amounts to consent, acceptance, or acquiescence.