Article R613-45 of the French Intellectual Property Code
The request for renunciation or limitation shall be made by a written declaration. Subject to its admissibility, it may be presented by the proprietor of the patent at any time, even when the effects of the patent have ceased. The request must, in order to be admissible: 1° Emanate from the proprietor of the patent entered, on the day of the request, in the National Patent Register, or from his…