The Philip Morris v. Uruguay case reaffirmed states' rights to regulate in the public interest, particularly for health measures. The ICSID tribunal ruled that Uruguay's tobacco regulations did not constitute expropriation or unfair treatment, setting a key precedent.

The Tecmed v. Mexico case (ICSID Case No. ARB(AF)/00/2) established that politically motivated regulatory actions can constitute expropriation. The tribunal ruled that Mexico’s refusal to renew a landfill permit violated investor protections, awarding $5.5M in damages.

The regulatory taking doctrine in international investment law mandates compensation when state regulations significantly impact investments, even without formal expropriation, balancing sovereign regulation and investor protection.

Fair and Equitable Treatment (FET) ensures stability, transparency, and non-discrimination in investment law. It protects investors' legitimate expectations and prevents arbitrary actions. Its evolving interpretation impacts global investment disputes and treaty practices.