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 Siemens v. Argentina case reaffirmed investor protections under BITs, ruling Argentina’s termination of Siemens’ contract as unlawful expropriation. The ICSID tribunal awarded Siemens over $217 million, reinforcing fair treatment and state obligations in investment disputes.

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.

In Saipem S.p.A. v. Bangladesh, ICSID ruled that judicial interference leading to loss of contractual rights is indirect expropriation. This case broadened protection for foreign investors under international investment law.

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.

Most-Favoured-Nation (MFN) treatment ensures foreign investors receive treatment no less favorable than investors from other nations. While promoting non-discrimination, its application in dispute resolution and substantive protections remains debated in investment law.