Title 26 › Subtitle Subtitle A— Income Taxes › Chapter 6— CONSOLIDATED RETURNS › Subchapter B— Related Rules › Part II— CERTAIN CONTROLLED CORPORATIONS › § 1563
When several corporations are owned by the same people, the tax law can treat them as one "controlled group" instead of separate companies. A group forms in a few ways. In a parent-subsidiary group, a parent company owns at least 80 percent of the voting power or value of one or more other corporations, which can be linked in a chain. In a brother-sister group, five or fewer individuals, estates, or trusts together own more than 50 percent of each corporation, counting only ownership that is identical across the companies. A combined group mixes both. Certain insurance companies in a group are treated as their own separate controlled group. A corporation counts as a member based on whether it belongs to the group on December 31 of the year. Some are excluded, such as tax-exempt organizations, certain foreign corporations, certain insurance companies, and companies that were in the group less than half the year. Some stock doesn't count at all, like nonvoting preferred stock and treasury stock. The rules also count stock you don't hold directly: stock you have an option to buy, stock held through a partnership, estate, trust, or corporation you own 5 percent or more of, and in many cases stock owned by your spouse, your children under 21, and, if you own more than 50 percent of a company, your parents, grandparents, grandchildren, and adult children. For some other laws that borrow this definition, the brother-sister test is stricter: the five or fewer owners must hold at least 80 percent, plus the identical-ownership 50 percent.
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Internal Revenue Code — Source: USLM XML via OLRC
Legislative History
Reference
Citation
26 U.S.C. § 1563
Title 26 — Internal Revenue Code
Last Updated
Apr 6, 2026
Release point: 119-73