Tax exemption phase-in for development finance company mandates staged inclusion and procedural audit and notification rules. The amendment creates a staged exemption for the North-Eastern Development Finance Corporation Limited by requiring progressive inclusion of proportions of its total income in taxable income over successive assessment years until full inclusion. It also modifies clause (23C) to limit the retrospective effect of certain notifications, mandates that notifications, approvals or rejection orders for applications made after assent be issued within twelve months of receipt, and requires entities whose income (before exemptions) exceeds the non-taxable maximum to obtain an accountant's audit and file the prescribed audit report with the return.