Article 21-13-1 of the French Civil Code
People aged at least sixty-five who have been lawfully and habitually resident in France for at least twenty-five years and who are the direct ascendants of a French national may claim French nationality by making a declaration pursuant to Articles 26 to 26-5. The conditions set out in the first paragraph of this article are assessed on the date on which the declaration referred to in the same first paragraph…