Deemed minimum taxable income based on book profit requires companies to treat taxable income as a proportion of book profit If a company's computed total income for the relevant previous year is less than thirty percent of its book profit, the taxable total income shall be deemed to equal thirty percent of that book profit; book profit is defined as net profit in the profit and loss account prepared under prescribed company law provisions, increased by specified items (including tax provisions, transfers to reserves, certain provisions and dividends, and expenditures related to Chapter III income) and reduced by specified withdrawals from reserves, Chapter III income credited, amounts attributable to businesses eligible for certain deductions, and allowable losses or depreciation as provided.