Article 11

(1) The countries of the Union shall, in conformity with their domestic legislation, grant temporary protection to patentable inventions, utility models, industrial designs, and trademarks, in respect of goods exhibited at official or officially recognized international exhibitions held in the territory of any of them.

(2) Such temporary protection shall not extend the periods provided by Article 4. If, later, the right of priority is invoked, the authorities of any country may provide that the period shall start from the date of introduction of the goods into the exhibition.

(3) Each country may require, as proof of the identity of the article exhibited and of the date of its introduction, such documentary evidence as it considers necessary.