Rule of the shorter term

The rule of the shorter term, also called the comparison of terms, is a provision in international copyright treaties. The provision allows that signatory countries can limit the duration of copyright they grant to foreign works under national treatment, to at most the copyright term granted in the country of origin of the work.

International copyright treaties such as the Berne Convention (BC) or the Universal Copyright Convention (UCC) work through national treatment: signatory countries agree to grant copyright to foreign works under their local laws and by the same rules they grant copyright to domestic works. Whether a work is eligible to copyright, and if so, for how long that copyright exists, is governed by the laws of the country where copyright on the work is claimed. The Berne Convention and also the UCC define only the minimum requirements for copyrights that all signatory countries must meet, but any country is free to go beyond this minimal common denominator in its legislation. This is most noticeable in the duration for which copyrights are upheld. The Berne Convention lays down a minimal general copyright term of 50 years beyond the death of an author (50 years p.m.a.). But many countries have a longer term, such as 70 years p.m.a., or even 100 years p.m.a..

One and the same work may thus be copyrighted for different times in different countries (since, per lex loci protectionis, the copyright rules of each country apply within its jurisdiction, regardless of the work's country of origin). Its copyright may have expired already in countries with a minimum term, but at the same time, it may still be copyrighted in other countries that have longer copyright terms. National treatment may thus lead to an imbalance: while works originating from countries with minimal copyright terms are copyrighted longer in other countries that have longer copyright terms. In that situation, works from a country that goes beyond the minimum requirements of a treaty may already have entered the public domain in foreign countries with shorter copyright term while still being copyrighted at home.

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