Condominium / Owned flat
A condominium is a specified part of an apartment building, which is typically an individually owned flat.
Every flat has its own registered “sub-number” under the apartment buildings main cadastral number. This means that each flat can have individually registered ownership.
The owner of the flat owns the apartment itself, while the plot, stairways, main entrance etc. is owned by all of the owners combined. The common ownership is administered through an owners association, which all owners have to be members of.