Title II — TAX ON INCOME sustained during the year incurred in business, trade or exercise of a profession conducted within the Philippines, when such losses are not compensated for by insurance or other forms of indemnity. The Secretary of Finance, upon recommendation of the Commissioner, is hereby authorized to promulgate rules and regulations prescribing, among other things, the time and manner by which the taxpayer shall submit a declaration of loss sustained from casualty or from robbery, theft or embezzlement during the taxable year: Provided, That the time to be so prescribed in the rules and regulations shall not be less than thirty (30) days nor more than ninety (90) days from the date of discovery of the casualty or robbery, theft or embezzlement giving rise to the loss; and (3) Net Operating Loss Carry-over. — The net operating loss of the business or enterprise for any taxable year immediately preceding the current taxable year, which had not been previously offset as deduction from gross income shall be carried over as a deduction from gross income for the next three (3) consecutive taxable years immediately following the year of such loss: Provided, however, That any net loss incurred in a taxable year during which the taxpayer was exempt from income tax shall not be allowed as a deduction under this Subsection: Provided, further, That a net operating loss carryover shall be allowed only if there has been no substantial change in the ownership of the business or enterprise in that — (i) Not less than seventy-five percent (75%) in nominal value of outstanding issued shares, if the business is in the name of a corporation, is held by or on behalf of the same persons; or (ii) Not less than seventy-five percent (75%) of the paid up capital of the corporation, if the business is in the name of a corporation, is held by or on behalf of the same persons. For purposes of this Subsection, the term ‘net operating loss’ shall mean the excess of allowable deduction over gross income of the business in a taxable year: Provided, That for mines other than oil and gas wells, a net operating loss without the benefit of incentives provided for under Executive Order No. 226, as amended, otherwise known as the Omnibus Investments Code of 1987, incurred in any of the first ten (10) years of operation may be carried over as a deduction from taxable income for the next five (5) years immediately following the year of such loss. The entire amount of the loss shall be carried over to the first of the five (5) taxable years following the loss, and any portion of 50 Isla Lipana & Co., the Philippine member firm of the PwC network