The dissertation focuses on the problems of regulation of the concept of indirect expropriation in international law and how the interests of a foreign investors could be protected in case of in- direct expropriation. It seeks to assess the concept of indirect expropriation and identify the issues related to its application in practice. The dissertation also focuses on the development of protection against indirect expropriation in international treaties with the special emphasis on the policy and protection to investor granted by the international investment protection treaties by the Republic of Lithuania. Also, the research deals with the procedural questions related to the actual protection of investors’ rights in international investment law. One of the main problems which has emerged recently – what are the possible ways of settlement of State and investor disputes after the Achmea judgement in the EU. The uncertainties left after this judgment are assessed in this research. Finally, the practical issues related to indirect expropriation with regards to the situation of protection of investors in Crimea and patents of COVID vaccines are analysed in this dissertation.