Questione giuridica chiave
Whether the disability rate was correctly determined, especially the hypothetical valid income.
Decisione estratta
The canton court had not sufficiently clarified whether the insured had voluntarily accepted a low wage or was constrained by invalidity-unrelated factors.
Motivazione estratta
Because the record did not allow a sufficiently established factual basis for the valid income, the inquiry duty was violated. Further evidence was needed before applying objective burden-of-proof rules.