; and (2) by inserting or after real-estate boards, . (b) Effective date The amendments made by this section shall apply to taxable years beginning after December 31, 2017. 4. Special rules relating to professional sports leagues (a) In general Section 501 of the Internal Revenue Code of 1986 is amended— (1) by redesignating subsection (s) as subsection (t); and (2) by inserting after subsection (r) the following new subsection: (s) Special rules relating to professional sports leagues No organization or entity shall be treated as described in subsection (c)(6) if such organization or entity— (1) is a professional sports league, organization, or association, a substantial activity of which is to foster national or international professional sports competitions (including by managing league business affairs, officiating or providing referees, coordinating schedules, managing sponsorships or broadcast sales, operating loan programs for competition facilities, or overseeing player conduct), and (2) has annual gross receipts in excess of $10,000,000. . (b) Effective date The amendments made by this section shall apply to taxable years beginning after December 31, 2017.