Deemed shipping income rule: tax on non-resident ships' receipts for carriage from Indian ports must be returned and taxed. A fixed proportion of amounts paid or payable for carriage of passengers, livestock, mail or goods shipped at an Indian port by ships belonging to or chartered by non-residents is deemed income accruing in India; the ship's master must file a return before departure, the Assessing Officer assesses and determines tax payable (with power to call for documents), the master is liable for payment, and port clearance is withheld until tax is paid or arrangements made.