A letter of marque and reprisal (French: lettre de marque; lettre de course) was a government license in the Age of Sail that authorized a private person, known as a privateer or corsair, to attack and capture vessels of a nation at war with the issuer. Once captured, the privateers could bring the case of that prize before their own admiralty court for condemnation and transfer of ownership to the privateer. A letter of marque and reprisal would include permission to cross an international border to conduct a reprisal (take some action against an attack or injury) and was authorized by an issuing jurisdiction to conduct reprisal operations outside its borders.