Questione giuridica chiave
Whether the federal complaint was admissible despite non-payment of the advance costs within the grace period.
Decisione estratta
The complaint could not be entertained because the advance costs were not paid nor duly proven within the prescribed non-extendable period.
Motivazione estratta
After warning under Art. 62(3) BGG, the appellant neither paid the CHF 1,000 advance costs in time nor provided the required proof of timely payment by debit confirmation; therefore non-entry followed under Art. 108(1)(a) BGG.