A municipality exercising its urban pre-emption right must show that it has a genuine project for the pre-empted property, even where the aim is to build up land reserves (1st case).

A public authority exercising its urban pre-emption right may simply refer to its resolution delimiting an area in which it intends to improve urban quality (1st case) or adopting a local housing programme (2nd case), provided that the resolution makes it possible to identify the nature of the project concerning the pre-empted property.