Tax on patent royalties: option for fixed low rate taxation with no deductions and five-year compliance lockout; applies to patentees Resident patentees may elect taxation of patent-related royalty income under a special regime whereby such royalty is subject to a fixed low rate while the assessee's remaining income is computed after excluding that royalty; no deductions or allowances are permissible in computing the royalty income. The option must be exercised by the prescribed due date. If, after electing, the assessee fails to offer the royalty income in accordance with the regime in any of the five succeeding assessment years, the assessee loses eligibility to claim the regime's benefit for a subsequent five-assessment-year period. 'Eligible assessee' and localisation and royalty definitions are specified.