EFF

EFF is one of the three-letter codes that follow the place of birth in the nominative extract published in the Journal Officiel. As with the other codes, no official source publishes their meaning, so all we do is count the people carrying each code in the decrees analysed.

The term “effet collectif” does describe a documented mechanism: according to service-public.gouv.fr, the minor children of a naturalized person also become French if their name is mentioned in the naturalization decree, minority being assessed on the date the decree is signed.

In practice that means a child's name can appear in a decree without having filed an application of their own. For families it also means the date that counts is the date the decree was signed, not the date it was published in the Journal Officiel.