Questione giuridica chiave
Whether the property gains tax assessment and later decisions were null because the appellant was allegedly not the taxable person.
Decisione estratta
No nullity: the appellant was not treated as the taxable person; at most he acted as the seller's representative and contractual debt-assumer.
Motivazione estratta
Nullity requires a particularly serious and obvious defect, such as lack of jurisdiction or grave procedural error. Here the authorities addressed the seller and, where necessary, corrected the record; the appellant's contractual assumption of the tax did not alter the legal tax debtor.