Title 26 › Subtitle Subtitle A— Income Taxes › Chapter 6— CONSOLIDATED RETURNS › Subchapter B— Related Rules › Part II— CERTAIN CONTROLLED CORPORATIONS › § 1563
Defines when several companies are treated as one “controlled group” for tax purposes and explains who counts as a member, what stock counts, and how ownership is figured. A parent-subsidiary chain counts if the parent or other companies own at least 80% of voting power or value in the others. A brother‑sister group counts when five or fewer people, estates, or trusts own more than 50% of voting power or value in each company and the ownership is identical across them. A group can be a mix of those two types, and insurance companies taxed under section 801 that are in such a group may be treated as a separate controlled group. One-line definitions: Controlled group — companies linked by the 80% parent-subsidiary rule or the 5-or-fewer owner 50% rule, or both. Component member — a corporation treated as in the group on the December 31 of a tax year (with rules for additions and exclusions). Excluded member — a company that is left out for the year if it was in the group for less than half the year, is a 501(a) tax-exempt entity, is a foreign corporation taxed under section 881, is an insurance company under section 801 (with limits), or is a franchised company meeting special conditions. Stock — generally excludes nonvoting preferred limited stock, treasury stock, and certain “excluded” stock described in the law. Constructive ownership — options count as owned; partnership, trust, estate, corporate, spouse, and family ownership can be attributed to certain people (often using a 5% test, age limits for children, and other precise rules). Employee and franchised-corporation rules and some ordering rules explain how to apply these tests.
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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 5, 2026
Release point: 119-73not60