§ 70.18  UNLAWFUL POSSESSION OF HIGHWAY SIGN OR MARKER.
   The Department and local authorities, with reference to traffic-control signs, signals, or markers owned by the Department or local authority, are authorized to indicate the ownership of the signs, signals, or markers in letters not less than 3/8 inch, or more than 3/4 inch in height, by use of a metal stamp, etching, or other permanent means.  Except for employees of the Department or local authorities, police officers, contractors, and their employees engaged in a highway construction contract or work on the highway approved by the Department or local authority, it is unlawful for any person to possess a sign, signal, or a marker so identified.
(ILCS Ch. 625, Act 5, § 11-313)  Penalty, see § 70.99