carte grise(registration certificate)
The French registration certificate (certificat d'immatriculation) is mandatory for French and foreign drivers domiciled in France wishing to travel on public roads in France or resell their vehicle.
Any holder of a car must be registered, regardless of the type of car and whatever the place where it was purchased.
In case of loss or theft of a French registration certificate (gray card), you can no longer drive on the public road with your vehicle or sell it. You must declare the loss or theft of the certificate to the French authorities and then request a duplicate. If the theft of your registration certificate occurs abroad, you can declare it to the local police, but you must declare it when you return to France to the French police or gendarmerie.
The owner of a vehicle must declare, within one month, his change of residence or head office, under penalty of incurring a fine of 4th class.