Voluntary disclosure limits settlement-based penalty relief; disclosures after search are not voluntary and cannot justify penalty reduction. Application of penalties under section 271(4A) requires genuine voluntary disclosure; penalties and assessments must not be reduced or framed as part of private settlements that grant unlawful concessions to the assessee. Disclosures following search or seizure of unaccounted cash or incriminating documents are not voluntary for penalty mitigation. The Board instructs strict adherence to prior guidance on the meaning of 'voluntary' and 'disclosure' to prevent unlawful settlement practices.