When a corporation subject to the regulation of the Public Service Commission, prior to April 2, 1915, was authorized by its charter or otherwise to hold stock in another corporation, such public service corporation may petition the Public Utility Commission for authority to increase the amount of stock of such other corporation which may be owned by the petitioning corporation. If the Commission finds and adjudges that such increase will promote the general good of the State, it may issue its certificate and order authorizing the same, and thereupon the charter or articles of incorporation shall be amended to conform to such order. (Amended 1959, No. 329 (Adj. Sess.), § 39(b), eff. March 1, 1961; 1985, No. 224 (Adj. Sess.), § 3.)