Any clause providing for indexation based on the minimum growth wage, on the general level of prices or wages or on the prices of goods, products or services not directly related to the purpose of the statute or agreement or to the activity of one of the parties is prohibited in the provisions of the statutes or agreements. Any clause providing for indexation to the change in the national construction cost index published by the Institut national des statistiques et des études économiques or, for commercial or craft activities defined by decree, to the change in the quarterly index of commercial rents published under the conditions laid down by the same decree by the Institut national de la statistique et des études économiques, is deemed to have a direct relationship with the purpose of an agreement relating to built property.
Any clause providing, for activities other than those referred to in the first paragraph and for activities carried out by the liberal professions, for indexation to the variation in the quarterly index of rents for tertiary activities published by the Institut national de la statistique et des études économiques under conditions laid down by decree is also deemed to be directly related to the purpose of an agreement relating to a building.
The provisions of the preceding paragraphs do not apply to statutory or contractual provisions concerning maintenance debts.
Life annuities constituted between private individuals, in particular pursuant to the provisions of article 759 of the Civil Code, must be considered as maintenance debts.