This document contains final regulations under sections 250 and 951A addressing the calculation of qualified business asset investment ("QBAI") for qualified improvement property ("QIP") under the alternative depreciation system ("ADS"). This document also contains final regulations with transition rules relating to the impact on loss accounts of net operating loss (NOL) carrybacks allowed by reason of the Coronavirus Aid, Relief, and Economic Security Act (the "CARES Act"). The final regulations affect United States shareholders of controlled foreign corporations, domestic corporations eligible for the section 250 deduction, and taxpayers that claim credits or deductions for foreign income taxes.