Kernrechtsfrage
Whether, in the overinsurance calculation, the pension fund may offset the insured person's full IV pension or only the congruent part attributable to the somatic impairment for which the fund is liable.
Extrahierter Entscheid
Only the part of the IV pension that is congruent with the disability risk covered by the occupational pension may be offset; here that is the somatically based half pension.
Extrahierte Begründung
Under the congruence principle, only benefits with the same event, person, time and purpose may be set off. The pension fund was not liable for the later psychiatric disability, so it may not benefit from first-pillar benefits covering that non-covered impairment.