Income Tax Act: Sections 44B & 172 govern profit computation for non-resident shipping businesses, with a 7.5% presumptive income rate.

Sections 44B and 172 of the Income Tax Act provide special provisions for computing profits and gains from shipping businesses of non-residents. Section 44B applies to non-residents with regular shipping operations in India, deeming 7.5% of freight received as income, without allowing the assessee to show income lower than this presumptive rate. Section 172 pertains to non-residents with irregular shipping activities, requiring a return before a ship departs from India, with tax assessed on 7.5% of the carriage amount. Tax must be paid before port clearance is granted. Chapter VI-A deductions are available, but depreciation set-off is not allowed under Section 44B.