Ab initio exemption for specified services requires SEZ units to declare exclusive use and maintain accounts, or repay with interest. Ab initio exemption is claimed via Form A 1 by a SEZ Unit/Developer supplying identification and service registration details, declaring accuracy and maintenance of accounts, and affirming that specified services are used for authorised SEZ operations. The form requires listing specified services and providers, disclosure of any DTA business, and an undertaking to repay exempted amounts with applicable interest if services are not exclusively used for authorised operations. The declaration must be signed by an authorised person and verified by the Specified Officer.