Minn. Stat. § 48.23: BANK NOT TO LEND ON ITS OWN STOCK OR PURCHASE SAME.

Any such bank shall make no loan or discount on the security of its own capital stock, nor be the purchaser or holder thereof, unless necessary to prevent loss upon a debt previously contracted in good faith, and all stock so acquired shall be disposed of, at public or private sale, within six months after it is so acquired.