Kernrechtsfrage
Whether the subtenant owed unjust enrichment for continued use of the premises after the main lease ended.
Extrahierter Entscheid
Yes. The continued occupation after 1 October 2002 was unauthorized; the enrichment equaled the objective rental value, reduced by amounts already paid.
Extrahierte Begründung
The sublease ended with the main lease, no statutory continuation under Art. 273b OR applied, and the landlord had clearly opposed the continued use by initiating eviction proceedings. The landlord's acceptance of CHF 1,000 monthly did not show consent to that amount as fair rent or waive the higher objective value.