Payments to specified persons: non-deductibility where payments exceed limits or are not via prescribed banking modes. Section 36 disallows deductions for expenditures to a specified person that the Assessing Officer finds excessive relative to fair market value, business needs, or benefit to the assessee. It defines specified persons by familial, management, ownership and substantial-interest relationships, and ties substantial interest to beneficial ownership or profit entitlement thresholds. The section further disallows deductions for payments in excess of prescribed single-day amounts unless made through specified banking or online modes, converts certain late payments into taxable income where earlier deductions were claimed, provides higher thresholds for goods carriage payments, and limits mark-to-market loss deductions except as otherwise permitted.