Where a bilateral investment treaty (BIT) or multilateral treaties - such as the World Trade Organization (WTO) trade rules or the North American Free Trade Agreement (NAFTA) - protect foreign investors from expropriations, they may seek claims in response to climate-related law and policy. Although this has not yet happened with respect to domestic climate laws, it has occurred with respect to other environmental laws10 despite the exemptions for environmental policy in most trade agreements, including the General Agreement on Tariffs and Trade of 1994 (GATT) Article XX11. These rules limit the ability of states to impose regulations of an internationally traded good on the basis of the process and production method (PPM) used to manufacture such good. This issue has already seen a challenge directly bearing on a country's ability to implement their NDCs.