The purpose of copyright registration is to place on record a verifiable account of the date and content of the work in question, so that in the event of a legal claim, or case of infringement or plagiarism, the copyright owner can produce a copy of the work from an official government source.
Before 1978, in the United States, federal copyright was generally secured by the act of publication with notice of copyright or by registration of an unpublished work. This has now been largely superseded by international conventions, principally the Berne Convention, which provide rights harmonized at an international level without a requirement for national registration. However, the U.S. still provides legal advantages for registering works of U.S. origin.
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