AS 21.40.020 does not apply to a purchase and sale, or sale and purchase, and AS 21.40.030 does not apply to a sale, of an equity security of a domestic stock insurance company not then or theretofore held in an investment account, by a dealer in the ordinary course of business and incident to the establishment or maintenance of a primary or secondary market, otherwise than on an exchange as defined in the Securities Exchange Act of 1934, as amended, for the security. The department may, by regulations that it considers necessary or appropriate in the public interest, define and prescribe terms and conditions regarding securities held in an investment account and transactions made in the ordinary course of business and incident to the establishment or maintenance of a primary or secondary market.