Kernrechtsfrage
Whether the claim to invalidate the estate-division agreement was timely despite the one-year avoidance period.
Extrahierter Entscheid
The avoidance declaration was timely because the complainant learned of the relevant mistake no later than 21 February 2000 and declared avoidance on 16 January 2001.
Extrahierte Begründung
The limitation period under Art. 31 OR starts only when the mistaken party recognizes the contract's significance; the opposing arguments were merely appellatory.