Question juridique clé
Whether the respondent's counterclaim for CHF 1,020,000 in transfer taxes could be set off against his debt to the appellant
Solution extraite
The counterclaim could not be set off because the appellant's alleged obligation to consent to a partial debt assumption was not of the same kind as the respondent's monetary debt.
Motifs extraits
A duty to consent to debt assumption is not a money debt and therefore does not satisfy the mutuality requirement for set-off under Art. 120(1) CO.