Article 11 outlines mandatory administrative requirements for taxpayers in Oman. Taxpayers must apply for a tax card during incorporation or when obtaining professional licenses. The Executive Regulations govern the issuance, renewal, and data requirements of these cards. Additionally, taxpayers must notify the Commercial Register of their name, address, and responsible employee details. If registration in the Commercial Register is not required, the taxpayer must notify the Tax Authority directly within 60 days of incorporation or commencement, and provide updates on any data modifications within 30 days of the change.