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15 U.S. Code § 2086 - Prohibition on industry-sponsored travel

Notwithstanding section 1353 of title 31 and section 2076(b)(6) of this title, no Commissioner or employee of the Commission shall accept travel, subsistence, or related expenses with respect to attendance by a Commissioner or employee at any meeting or similar function relating to official duties of a Commissioner or an employee, from a person—
seeking official action from, doing business with, or conducting activities regulated by, the Commission; or
whose interests may be substantially affected by the performance or nonperformance of the Commissioner’s or employee’s official duties.