Ill. Admin. Code tit. 92, § 1207.10 – Designating Agents for Service of Process

a) Filing a completed copy of the Commission's Designation of Agent for Service of Process form; or
b) Filing a letter, signed by the person or an owner, partner, or officer of the legal entity making the filing, containing the information set forth in Section 1207.20 of this Part.

Any person subject to the jurisdiction of the Illinois Commerce Commission ("Commission") under the Illinois Commercial Transportation law (Ill. Rev. Stat. 1985, ch. 95½, pars. 18c-1101 et seq.) shall designate an agent for service of process by either: