Article 9 mandates that if the owner of an establishment or permanent establishment is outside Oman during any tax year, they must designate a Principal Officer to discharge tax obligations in their absence. The appointed Principal Officer must be physically present in Oman to perform these duties. Furthermore, the Law restricts the Principal Officer from being absent from the country for more than ninety days during any tax year. This ensures that there is always a locally available responsible party to interact with the Tax Authority and manage the entity's tax affairs.