Waiver of penalty and immunity from prosecution depend on tax payment, prescribed additional tax, and no pending appeal. Waiver of penalty and immunity from prosecution may be granted on application to the Assessing Officer where the assessee has paid the assessed tax and interest within the notice period, paid the prescribed additional income-tax in cases of under-reported income, and has not filed an appeal. The application must be made within one month from the end of the month of receipt of the relevant order. The Assessing Officer must decide the application within three months, hear the assessee before rejection, and the order is final; no appeal or revision lies where the application is accepted.