Claims of regulatory expropriation have been raised in diverse venues adjudicating international investment disputes Although a basic consensus position has emerged on a state's power to affect private property rights without compensation to investors, the legality of such actions will and should depend on the specific regime and institutional context in which they are appraised. A uniform doctrinal answer is thus impossible and undesirable, and many worries about fragmentation of international law are misplaced.
Ratner, Steven R. "Regulatory Takings in Institutional Context: Beyond the Fear of Fragmented International Law." Am J. Int'l L. 102, no. 3 (2008): 475-528.