Kernrechtsfrage
Whether loss carryforwards from prior years had to be accepted as definitively established.
Extrahierter Entscheid
The tax authorities could review the amount of prior-year losses when deciding the loss deduction under Art. 67 DBG; the earlier assessments did not bind them as to the loss amount.
Extrahierte Begründung
Only the dispositive part of a tax assessment is res judicata, not its reasons. A zero-profit assessment only establishes no taxable profit, not the amount of loss underlying it.