Despite some inherent risks, foreign direct investment (FDI) is for some the preferred method of investment. The rising number of bilateral investment treaties governing FDI is merely reflective of this investment vehicle’s popularity. Since the early-nineteenth century, developed countries have sought to gain protection for investors engaging in these investment opportunities. One such protection, the Hull Doctrine, requires national governments to fully compensate investors in cases of unlawful expropriation. Until World War II, when developing countries began applying their own domestic eminent domain law to foreign investors, the Hull Doctrine was considered binding, customary international law. This Note analyzes the effects of recent trade treaties, the Trans-Pacific Partnership and the Transatlantic Trade and Investment Partnership, and assesses whether these treaties’ inclusion of the Hull standard re-establishes the doctrine as a twenty-first century customary international norm.