(a) In addition to investments authorized under section 356A.06, subdivision 7, a teachers retirement fund association may receive, hold, and dispose of:
(1) real estate or personal property acquired by it, whether the acquisition was by purchase, or any other lawful means, as provided in this chapter or in the association's articles of incorporation; and
(2) domestic government and corporate debt obligations that are not rated in the top four quality categories by a nationally recognized rating agency, and comparable unrated securities if the percentage of these assets does not exceed five percent of the total assets of the pension plan or 15 percent of the pension plan's nonequity assets, whichever is less, if the pension plan's participation is limited to 50 percent of a single offering of the debt obligations, and if the pension plan's participation is limited to 25 percent of an issuer's debt obligations that are not rated in the top four quality categories.
(b) In addition to other authorized real estate investments, an association may also invest funds in Minnesota situs nonfarm real estate ownership interests or loans secured by mortgages or deeds of trust. The board may also certify assets for investment by the State Board of Investment as provided under section 11A.17.