26 U.S.C. § 6046: Returns as to organization or reorganization of foreign corporations and as to acquisitions of their stock

each United States citizen or resident who becomes an officer or director of a foreign corporation if a United States person (as defined in section 7701(a)(30)) meets the stock ownership requirements of paragraph (2) with respect to such corporation, who acquires stock which, when added to any stock owned on the date of such acquisition, meets the stock ownership requirements of paragraph (2) with respect to a foreign corporation, or who acquires stock which, without regard to stock owned on the date of such acquisition, meets the stock ownership requirements of paragraph (2) with respect to a foreign corporation, each person (not described in subparagraph (B)) who is treated as a United States shareholder under section 953(c) with respect to a foreign corporation, and each person who becomes a United States person while meeting the stock ownership requirements of paragraph (2) with respect to stock of a foreign corporation. the total combined voting power of all classes of stock of such corporation entitled to vote, or the total value of the stock of such corporation. The returns required by subsection (a) shall be in such form and shall set forth, in respect of the foreign corporation, such information as the Secretary prescribes by forms or regulations as necessary for carrying out the provisions of the income tax laws, except that in the case of persons described only in subsection (a)(1)(A) the information required shall be limited to the names and addresses of persons described in subparagraph (B) or (C) of subsection (a)(1). For purposes of subsection (a), stock owned directly or indirectly by a person (including, in the case of an individual, stock owned by members of his family) shall be taken into account. For purposes of the preceding sentence, the family of an individual shall be considered as including only his brothers and sisters (whether by the whole or half blood), spouse, ancestors, and lineal descendants. Any return required by subsection (a) shall be filed on or before the 90th day after the day on which, under any provision of subsection (a), the United States citizen, resident, or person becomes liable to file such return (or on or before such later day as the Secretary may by forms or regulations prescribe). No information shall be required to be furnished under this section with respect to any foreign corporation unless such information was required to be furnished under regulations which have been in effect for at least 90 days before the date on which the United States citizen, resident, or person becomes liable to file a return required under subsection (a). For provisions relating to penalties for violations of this section, sections 6679 and 7203.