Tonnage tax scheme abuse: exclusion follows where transactions produce a tax advantage or affect non tonnage profits. Section 234 provides that the tonnage tax scheme does not apply where a tonnage tax company is party to a transaction or arrangement constituting an abuse of the scheme by yielding a tax advantage to others or to the company's non-tonnage activities. 'Tax advantage' includes adjustments to allowances, interest, costs or apportionments that reduce taxable income or increase losses for non-tonnage activities, or transactions producing more than ordinary profits from tonnage activities. The Assessing Officer may exclude the company from the scheme by written order after serving a show cause notice and obtaining prior approval of the Principal Chief Commissioner or Chief Commissioner; exclusion is effective from the first day of the tax year in which the transaction occurred. The section excludes bona fide commercial transactions not entered into for tax advantage.