Ind. Code § 8-4-7-5

Sec. 5. The interest of each proprietary company in the union company in its capital stock and in its property and effects of every kind shall be deemed an appurtenance to the railroad of such proprietary company, and shall not be transferable or alienable otherwise than with and as a part of the railroad of such proprietary company. The union company shall issue to each proprietary company a certificate or certificates setting forth the interest or stock of such proprietary company in such union company, but such certificate shall express upon its face that it is not transferable, except as appurtenant to the railroad of such proprietary company.