Excise duty exemption based on value addition enables refunds or deemed cash credit for qualifying units in specified states. Exempts from central excise duty an amount equivalent to duty payable on value addition for goods of the First Schedule cleared from units in specified northeastern States, subject to Table rates, Annexure exclusions, eligibility for new or substantially expanded units within a time window, and a maximum ten-year period. Claimants must file monthly statements, receive verification and refund or may opt to credit the calculated amount to an account current as deemed cash payment; irregular or excess credits are recoverable. Manufacturers may apply for a special rate based on audited actual value addition, with procedures for provisional refunds, fixation, retrospective effect and adjustments.