Section 215 ILCS 5/5 - Classes of companies(1) All Companies now or hereafter authorized to transact business in this State shall be classified according to their functions into one or more of the classes of insurance enumerated in section 4.(2) No company shall be authorized to transact any kind or kinds of business other than those enumerated in its respective class, or classes, except as otherwise specifically provided in this Code, but any company, upon complying with all applicable provisions of this Code, may be authorized to transact all or any part of its business on the basis of reinsurance, except that no certificate of authority shall be limited in whole or in part to reinsurance unless the restriction as to such reinsurance is expressed in the articles of incorporation of said company.