No insurer may invest any of its funds in or lend any of its funds upon the security of:

1. (a) Issued shares of its own capital stock except with the written permission of the director or his designee which may be granted, at his discretion, where the purpose of the acquisition is in connection with a lawful plan for mutualization of the insurer, or in furtherance of a retirement, pension, or incentive program for officers or employees of the insurer, which plan has been approved by the stockholders, or if otherwise the acquisition is shown to be for the benefit of all stockholders; but in no event may shares so acquired be admissible as an asset or shown as an asset in any financial statement of the insurer.
2. (b) Securities issued by a corporation which is insolvent at the time of the proposed investment except upon the written approval of the director or his designee.
3. (c) Securities which will subject the insurer to any assessment other than for taxes or wages.
4. (d) Any investment or security which is found by the director or his designee to be designed to evade any prohibition of this chapter.