Service tax exemption for services under MEIS scrip permits service tax debit validation and entitlement to drawback or credit. Taxable services provided against an MEIS duty credit scrip are exempt from service tax provided the scrip is registered with the Customs Authority and presented with prescribed invoice documentation; Customs shall debit the notional service tax on the reverse of the scrip and notify the Central Excise Officer, whose validation on the scrip and record of payment enables the holder to claim drawback or CENVAT credit. Short-paid tax or interest arising from point-of-taxation or rate differences must be paid by the scrip holder, and debited scrips must be presented to the Central Excise Officer within thirty days with an undertaking.