Indiana Code Title 8. Utilities and Transportation § 8-23-9-48

Sec. 48. (a) A state highway may not be torn up or otherwise disturbed for any purpose without the written permit of the commissioner and then only in accordance with the regulations prescribed by the commissioner.  All work shall be done under the department's supervision, and all the cost of replacing the highway in as good condition as before the highway was disturbed, shall be paid by the person to whom or in whose behalf the permit was given.  The department shall mark with proper markers, showing the number of the highway, all state highways, including the routes of the highways through cities and towns, together with the caution and direction signs that the department considers advisable.

(b) It is a Class C infraction for a person to put, place, or maintain within twenty (20) feet of the right-of-way limits of a state highway, outside the limits of a city or town a sign or other device containing the words “stop”, “caution”, “slow”, or any other word or device that also might be construed as a warning to persons using the highway.

(c) It is a Class C infraction for a person to construct or maintain a sign or advertising device within one hundred (100) feet of the right-of-way of such a highway that obstructs the view of the highway of a person traveling the highway for a distance of five hundred (500) feet or less from the sign or device as the person approaches the sign or device.  The department may remove unlawful signs, markers, and devices.