What is Foreign Sovereign Immunities Act?

Legal Definition
The Foreign Sovereign Immunities Act (FSIA) of 1976 is a United States law, codified at Title 28, §§ 1330, 1332, 1391(f), 1441(d), and 1602–1611 of the United States Code, that establishes the limitations as to whether a foreign sovereign nation (or its political subdivisions, agencies, or instrumentalities) may be sued in U.S. courts—federal or state. (In international law, government protection against lawsuits in foreign courts is known as state immunity; government immunity in domestic courts is known as sovereign immunity.) It also establishes specific procedures for service of process, attachment of property and execution of judgment in proceedings against a foreign state. The FSIA provides the exclusive basis and means to bring a lawsuit against a foreign sovereign in the United States. It was signed into law by President Gerald Ford on October 21, 1976.

Since the passage of the FSIA in 1976, numerous legal issues have arisen in regards to the manifold interpretations of the Act, leading to the formation of an American Bar Association working group that seeks to reform FSIA.
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