Iowa Code § 506.8: Liability to stockholders.

Any person, association, or corporation who sells or aids in selling or causes to be sold any stock, certificate of membership, or evidence of interest in any such corporation or association, in violation of law, shall be personally liable to any person to whom the person, association or certificate of membership or evidence of interest, in an amount equal to the price paid therefor by such person with legal interest, and suit to recover the same may be brought by such purchasers, jointly or severally, in any court of competent jurisdiction.