Minn. Stat. § 342.58

A health care practitioner who knowingly refers patients to a medical cannabis business or to a designated caregiver, who advertises as a retailer or producer of medical cannabis flower or medical cannabinoid products, or who issues certifications while holding a financial interest in a cannabis retailer or medical cannabis business is guilty of a misdemeanor and may be sentenced to imprisonment for not more than 90 days or to payment of not more than $1,000, or both.