Mo. Rev. Stat. § 149.051: Failure to affix stamps, penalty — presumption that unstamped cigarettes are intended for sale.

1. Any person who fails to affix the stamps within the time and manner required of him under the provisions of this chapter shall pay, as a part of the tax imposed hereunder, a penalty equal to one hundred percent of the initial tax liability, and the tax and penalty thereon shall bear interest at the annual adjusted prime rate of interest as determined by section 32.065.

2. No person, other than licensed wholesalers or other persons as specifically provided for in this chapter, shall possess for the purpose of sale any cigarettes to which the stamps or meter units required by this chapter are not affixed.

3. Mere possession of an unstamped package of cigarettes by any person, except under circumstances specifically prescribed by this chapter, shall be prima facie evidence that the cigarettes are intended for sale.