Land registry map (cadastre) of the town of Valbrume: click a plot, or search for an address or a plot number. When the owner is a legal entity (company, town, association…), its name is public; a private individual's is not.

In real life: cadastre.gouv.fr and Géoportail for the map, and the « legal-entity plot files » published by the French tax authority (DGFiP) on data.gouv.fr for the owners. A property holding company (SCI) often acts as a screen: you then have to trace its officers in the company register.