In order to preserve the diversity of the cinematographic offer, any practice is prohibited and any contractual clause is deemed to be unwritten which is likely to make either the choice of distribution or programming of cinematographic works in cinemas, or the determination of the rate of the contribution proportional to the box office receipts provided for in articles L. 213-9 to L. 213-11, dependent on the conditions of determination and payment of the contribution provided for in article L. 213-16 or the financing of the initial installation of digital projection equipment.