Missouri Revised Statutes Title XXVI. Trade and Commerce § 413.135. Prohibited actions

(1) Sell, offer for sale or install for use as a commercial device any incorrect weight or measure;

(2) Remove from any weight or measure any tag, seal or mark placed thereon by the director, without written authorization from the director;

(3) Dispose of any rejected or condemned weight or measure in a manner contrary to law or regulation;

(4) Obstruct, hinder, impair or prevent the performance of a governmental function by a weights and measures official by the use or threat of violence, force or other physical interference or obstacle;

(5) Use, or have in possession for current use as a commercial device, any weight or measure that has not been inspected and sealed by the director within the time specified by this act or regulation promulgated hereunder, except that this subdivision does not apply if the director has been notified that a device is available for inspection or reinspection and the director grants or has granted authorization for its temporary commercial use pending an official inspection;

(6) Use in retail trade a weight or measure that is not positioned so that its indications may be accurately read and the weighing or measuring operation observed from some position which may be reasonably assumed by the customer and operator. Devices used for medical prescription and those used exclusively to prepare packages in advance of retail sale are exempt from this requirement;

(7) Keep for the purpose of sale, advertise, offer or expose for sale or sell any commodity, thing or service in a condition or manner contrary to law or regulation.