Article L145-19 of the French Commercial code
To benefit from the priority right provided for in article L. 145-17, the tenant must, on vacating the premises or, at the latest within three months thereafter, notify the landlord of his wish to use the premises, by extrajudicial act or by registered letter with acknowledgement of receipt, informing the landlord of his new domicile; he must likewise notify, under penalty of forfeiture, any new change of domicile. A landlord…