The amount of basic income of a profit-seeking enterprise shall be the sum of the taxable income as calculated in accordance with the Income Tax Act and any income that falls under the following subparagraphs:
1. The amount of income for which income tax is suspended in accordance with Article 4-1 and Article 4-2 of the Income Tax Act.
2. The amount of income for which profit-seeking enterprise income tax is exempted in accordance with Article 9, Article 9-2, Article 10, Article 15 and Article 70-1 of the now-abolished Statute for Upgrading Industries before its repeal.
3. The amount of income for which profit-seeking enterprise income tax is exempted in accordance with Article 8-1 of the now-abolished Statute for Upgrading Industries before its amendment on December 31, 1999.
4. The amount of income exempted from profit-seeking enterprise income tax in accordance with Article 28 of the Statute for Encouragement of Private Participation in Transportation Infrastructure Projects.
5. The amount of income exempted from profit-seeking enterprise income tax in accordance with Article 36 of the Act for Promotion of Private Participation in Infrastructure Projects.
6. The amount of income exempted from profit-seeking enterprise income tax in accordance with Article 18 of the Act for Establishment and Administration of Science Parks.
7. The amount of income for which profit-seeking enterprise income tax is exempted in accordance with Article 15 of the Act for Establishment and Administration of Science Parks before its amendment on January 20, 2001.
8. The amount of income exempted from profit-seeking enterprise income tax in accordance with Article 37 of the Business Mergers and Acquisitions Act.
9. The amount of income exempted from profit-seeking enterprise income tax in accordance with Article 13 of the Offshore Banking Act. However, such amount of income does not include the total revenue derived from a credit extension that shall be taxed at the prescribed withholding rate in accordance with Article 73-1 of the Income Tax Act.
10. The amount of income that is entitled to reduction or exemption from profit-seeking enterprise income tax or that is excluded from the income tax base as may be provided for in such laws after the implementation of this Act and publicly announced by the Ministry of Finance (hereinafter referred to as the MOF).
In the case of an amount of income which is added back in accordance with Subparagraph 1 and Subparagraph 9 of the preceding paragraph, the loss incurred after this Act coming into force and assessed by the tax authority may be offset against the income of the same subparagraph within five years from the year after such losses are derived.
Where any profit-seeking enterprise sells, starting from the fiscal year 2013, the stocks referred to in Article 4-1 of the Income Tax Act that were held for a period of three years or more, such enterprise, when calculating the amount of income derived from such transactions in the current year, should deduct the losses incurred by selling the stocks referred to in Article 4-1 of the Income Tax Act that were held for a period of three years or more in the same year, and, if the result is a positive balance, only one-half of such balance should be added into the current year's income derived from such transactions; otherwise, the preceding paragraph governs.
If a loss is incurred in a type of transaction for which the income is added back in accordance with Subparagraph 10 of Paragraph 1, Paragraph 2 may apply mutatis mutandis if so publicly announced by the MOF.