This article focuses on the applicability of bilateral investment treaties on the conduct of the occupying power towards foreign investments situated in the occupied territory. It examines the content of the obligation to respect the laws in force in the occupied territory as prescribed by Art. 43 of the Convention (IV) respecting the Laws and Customs of War on Land. Some authors proposed an idea that this obligation is a gateway provision for the applicability of international treaties which are in force in the occupied territory on the conduct of the occupier. They refer to the case-law dealing with the applicability of human rights treaties in occupied territories. However, after the interpretation of this provision and inquiry into the case-law, this paper reaches the conclusion that the obligation to respect the laws in force does not have this effect. Instead, it deals with the legislative powers of the occupying power.