Using a legal history methodology, this paper examines existing marine renewable energy law and policy in Nova Scotia with a focus on its application in the Bay of Fundy. This paper critically assesses the current approach to coastal management in light of recent recommendations summarized in the Fournier report. This paper argues that, despite clear calls to develop integrated ocean management and marine spatial planning in policies and regulations, Canada and Nova Scotia have failed to do so because of unclear federal-provincial boundaries. Ambiguous domestic borders in the Bay of Fundy have been at the source of an overly cautious, issue-driven and jurisdictionally uncertain approach to ocean governance which has permeated marine renewable energy law. This approach is unsuited for today's environmental objectives and does not hold promise for goals to reconcile competing interests in increasingly industrialised waters. Through a historical account of shifting limits in the Bay of Fundy, this paper connects existing doubts and frictions associated with domestic offshore boundaries to ineffective coastal management in an attempt to renew interest in federal-provincial maritime delimitation.