Patents and Designs Act 1907

41 Provision as to anticipation

(1) An invention, covered by any patent applied for on or after the first day of January one thousand nine hundred and five, shall not be deemed to have been anticipated by reason only of its publication in a specification left pursuant to an application made in the United Kingdom not less than fifty years before the date of the application for the patent, or of its publication in a provisional specification of any date not followed by a complete specification.

(2) A patent shall not be held to be invalid by reason only of the invention in respect of which the patent was granted, or any part thereof, having been published prior to the date of the patent, if the patentee proves to the satisfaction of the court that the publication was made without his knowledge and consent, and that the matter published was derived or obtained from him, and, if he learnt of the publication before the date of his application for the patent, that he applied for and obtained protection for his invention with all reasonable diligence after learning of the publication.