Kernrechtsfrage
Whether the sublease termination was invalid because the sublease rent was allegedly excessive compared with the head lease rent, or due to an alleged fundamental mistake.
Extrahierter Entscheid
No. A mere disparity between performance and counterperformance is not immorality under Art. 20 OR; the overreaching problem is governed by Art. 21 OR. A rent mismatch was not a decisive basis of the sublease contract, and even if a mistake affected only part of the agreement, the appellant failed to show the parties would have contracted on different terms.
Extrahierte Begründung
The court held that the argument of immorality failed as a matter of law. It further accepted that, at most, a partial invalidity rule could apply, but found no objective indication that the respondent would have entered the sublease at a lower rent. Therefore the appellant had no basis to remain in the premises.