Penalty immunity for disclosed net wealth available before penalty imposition, withdrawable for concealment or false evidence. The Commissioner may grant immunity from penalty to a person who, after settlement proceedings have abated and penalty proceedings are pending, applies before penalty imposition and, after abatement, has cooperated with the wealth-tax authority and made a full and true disclosure of net wealth and its derivation; such immunity may be conditional and is withdrawable for noncompliance or if the person concealed material particulars or gave false evidence, in which case penalties apply as if immunity had not been granted.