ownership rules used in determining related party In determining whether persons are related within the meaning of section 267(b) or 707(b), the constructive ownership rules of section 318 shall apply in lieu of the constructive ownership rules which would otherwise apply, except that in applying such rules the term stock shall include capital, profits, or other beneficial interests in persons other than corporations. (2) Control (A) Corporations In the case of a corporation, the term control has the meaning given such term by section 304(c) (without regard to paragraph (3)(B) thereof). (B) Other entities In the case of a person other than a corporation, such term means the ownership, directly or indirectly, of at least 50 percent of the capital, profits, or other beneficial interests in the person. (e) Regulations The Secretary shall prescribe such regulations or other guidance as may be necessary or appropriate to carry out the provisions of this section, including regulations— (1) providing for such adjustments to the application of this section as are necessary to prevent the avoidance of the purposes of this section, including through the use of unrelated persons, or conduit transactions, and (2) modifying the constructive ownership rules under section 318 to the extent necessary to apply such rules to capital, profits, or other beneficial interests as well as stock. . (b) Disallowance of credits against tax Subparagraph (B) of section 26(b)(2) of the Internal Revenue Code of 1986 is amended by inserting or section 59B (relating to surtax on certain amounts received by investment firms from controlled target firms) after anti-abuse tax) . (c) Conforming amendments (1) The table of parts for subchapter A of chapter 1 of the Internal Revenue Code of 1986 is amended by adding after the item relating to part VII the following new item: Part VIII. Surtax on certain amounts received by investment firms . (2) Section 871(b)(1) of such Code is amended by inserting and shall be taxable as provided in section 59B on