who are members of such group in such manner as the Secretary or their delegate shall by regulations prescribe. For purposes of the preceding sentence, the term controlled group has the meaning assigned to it by subsection (a) of section 1563, except that for such purposes the phrase more than 50 percent shall be substituted for the phrase at least 80 percent in each place it appears in such subsection. Under regulations prescribed by the Secretary, principles similar to the principles of the preceding two sentences shall be applied to a group of brewers under common control where one or more of the brewers is not a corporation. (B) Foreign manufacturers and importers For purposes of paragraph (4), in the case of a controlled group, the 6,000,000 barrel quantity specified in paragraph (1)(C)(i) shall be applied to the controlled group and apportioned among the members of such group in such manner as the Secretary shall by regulations prescribe. For purposes of the preceding sentence, the term controlled group has the meaning given such term under subparagraph (A). Under regulations prescribed by the Secretary, principles similar to the principles of the preceding two sentences shall be applied to a group of brewers under common control where one or more of the brewers is not a corporation. (C) Single taxpayer Pursuant to rules issued by the Secretary, two or more entities (whether or not under common control) that produce beer marketed under a similar brand, license, franchise, or other arrangement shall be treated as a single taxpayer for purposes of the application of this subsection. . (e) Effective date The amendments made by this section shall apply to beer removed after December 31, 2017. 13804. Simplification of rules regarding records, statements, and returns (a) In general Subsection (a) of section 5555 is amended by adding at the end the following: For calendar quarters beginning after December 31, 2017, and before January 1, 2020, the Secretary shall permit a person to employ a unified system for any