Reduced tax rate for mineral oil business of Indian companies with government participation and special mixed-income treatment Where the Central Government has an agreement for participation in an Indian company's mineral-oil business, profits solely from prospecting, extraction or production of mineral oils are taxed under a reduced single-rate regime with no Union surcharge; where total income includes both mineral-oil profits and other income, mineral-oil profits are taxed under the reduced regime and the remaining income is taxed under the normal provisions with applicable surcharge.