510 ILCS 5/2.16
"Owner" means any person having a right of property in an animal, or who keeps or harbors an animal, or who has it in his care, or acts as its custodian, or who knowingly permits a dog to remain on any premises occupied by him or her. "Owner" does not include a feral cat caretaker participating in a trap, spay/neuter, vaccinate for rabies, and return program.
(from Ch. 8, par. 352.16)
(Source: P.A. 101-295, eff. 8-9-19.)