26 U.S.C. § 6806 (2024) — Occupational tax stamps

Every person engaged in any business, avocation, or employment, who is thereby made liable to a special tax (other than a special tax under subchapter B of chapter 35, under subchapter B of chapter 36, or under subtitle E) shall place and keep conspicuously in his establishment or place of business all stamps denoting payment of such special tax.