Article R522-7 of the French Code of civil enforcement procedures
A creditor who obtains a writ of execution recording the existence of his claim shall serve on the debtor a conversion deed containing, on pain of nullity : 1° A reference to the report of the protective attachment; 2° A statement of the writ of execution; 3° A separate statement of the sums to be paid in principal, costs and accrued interest, together with an indication of the interest rate;…