### Question
How is the term brother-sister controlled group defined?


### Answer
The term **brother-sister controlled group** is defined in *26 CFR § 1.1563-1* as the following:

> two or more corporations if the same five or fewer persons who are individuals, estates, or trusts own (directly and with the application of the rules contained in § 1.1563-3(b)) stock possessing—

(A) At least 80 percent of the total combined voting power of all classes of stock entitled to vote or at least 80 percent of the total value of shares of all classes of stock of each corporation (the 80 percent requirement);

#### Citation:
  - *26 CFR § 1.1563-1*
