Compiled Laws, Chapter 750. Michigan Penal Code § 750.151

Sec. 151. All contracts, agreements, understandings, and combinations made, entered into, or knowingly assented to, by and between any parties capable of making a contract or agreement which would be valid at law or in equity, the purpose or object or intent of which shall be to limit, control, or in any manner to restrict or regulate the amount of production or the quantity of any article or commodity to be raised, or produced by mining, manufacture, agriculture, or any other branch of business or labor, or to enhance, control or regulate the market price thereof, or in any manner to prevent or restrict free competition in the production or sale of any such article or commodity, shall be illegal and void, and every such contract, agreement, understanding, and combination shall constitute a criminal conspiracy. And every person who, for himself or herself personally, or as a member, or in the name of a partnership, or as a member, agent, or officer of a corporation, or of any association for business purposes of any kind, who shall enter into or knowingly consent to any such void and illegal contract, agreement, understanding, or combination, shall be deemed a party to such conspiracy.

All parties so offending shall be guilty of a misdemeanor punishable by imprisonment in the county jail for not more than 6 months or a fine of not more than $750.00. And the prosecution for offenses under this section may be instituted and the trial had in any county where any of the conspirators become parties to such conspiracy, or in which any 1 of the conspirators shall reside.This section shall in no manner invalidate or affect contracts for what is known and recognized as common law and in equity as contracts for the “good will of a trade or business”; but all such contracts shall be left to stand upon the same terms and within the same limitations recognized at common law and in equity.