Kernrechtsfrage
Whether the creditor failed to continue enforcement without notable interruption under Art. 511 CO and thereby released the surety.
Extrahierter Entscheid
A delay of more than seven months after knowledge that the pledged property would not cover the debt was an undue lapse; the creditor did not act with the diligence required of a prudent businessperson.
Extrahierte Begründung
The court applied the good-faith standard and analogized to the four-week period in Art. 510(3) CO as a benchmark. Since the bank knew on 20 March 1997 that the claim would not be covered yet waited until 22 October 1997 to start ordinary proceedings, the cantonal court correctly found a notable interruption.