The rules of section 958(a) and this section provide a limited form of stock attribution primarily for use in determining the amount taxable to a United States shareholder under section 951(a). These rules also apply for purposes of other provisions of the Code and regulations which make express reference to section 958(a).
Example. Domestic corporation M owns 75 percent of the one class of stock in foreign corporation R, which in turn owns 80 percent of the one class of stock in foreign corporation S, which in turn owns 90 percent of the one class of stock in foreign corporation T. Under this paragraph, R Corporation is considered as owning 80 percent of the 90 percent of the stock which S Corporation owns in T Corporation, or 72 percent. Corporation M is considered as owning 75 percent of such 72 percent of the stock in T Corporation, or 54 percent. Since M Corporation is a domestic corporation, the attribution under this paragraph stops with M Corporation, even though, illustratively, such corporation is wholly owned by domestic corporation N.
26 C.F.R. §1.958-1