35 Ill. Adm. Code 105.400
Parties
Section 105
Section 105.400Â Parties
a)        Petitioner. The person who files a petition for review of the
Agency's final decision made under Title XVI of the Act [415 ILCS 5/57 through
57.19] (or under the former Section 22.18b(g) of the Act) must be named as
petitioner.
b)        Respondent. The Agency must be named as the respondent.