Approval conditions for tax exemption tightened: prescribed applications, timelines and compliance checks now required for charitable and institutional exemptions. Section 10 amendments condition tax exemption under clause (23C) on prescribed applications to the Principal Commissioner/Commissioner within specified timelines, require inquiries into genuineness and legal compliance, and provide approvals generally for five years (provisional three years). The amendments clarify that voluntary contributions directed to corpus are excluded from income for the proviso, provide transitional treatment for pending applications, and introduce a new clause (23FE) excluding specified persons' investment income subject to investment window, holding period and eligible investment conditions, with taxability restored if conditions later fail.