01 April 2026 Real Estate: 20 Years of Regularization of Building Permits

The firm is pleased to announce the publication in RDI of an article by Xavier de Lesquen on 20 years of the regularization of building permits.

Indeed, twenty years have passed since the 2006 law that introduced Article L. 600-5 of the French Urban Planning Code, the starting point of a step-by-step transformation in urban planning litigation practice. That transformation builds on the earlier Central Park case law of 1995, later brought to prominence by the Fontaine de Villiers decision of 2004.

The article examines the 52 reported or published decisions of the Conseil d’État up to the end of 2025 on the application of Articles L. 600-5 and later L. 600-5-1. This overview reveals the striking consistency of the court’s role across the three existing avenues for regularizing a building permit: spontaneous regularization through application of the Central Park / Fontaine de Villiers line of case law; the stay of proceedings under Article L. 600-5-1; and partial annulment under Article L. 600-5.

The article’s central argument — since every article needs one — is that seeking a unified approach to the court’s role helps ensure coherence, simplicity, and neutrality in the procedural rules governing the regularization process.

By a happy coincidence of timing, the Conseil d’État today delivered its much-anticipated Section decision on whether a permit may still be regularized even where the project site has been reclassified as non-buildable since the stay of proceedings under Article L. 600-5-1 was ordered (decision no. 494252 et al., 31 March 2026). The ruling provides an excellent illustration of the benefits of a unified conception of the court’s role in the regularization process.