35 ILCS 190/1-20: Determining the location of a user-consumer.

(a) The location of a user-consumer shall be determined by the provider of targeted advertising services using the totality of the user-consumer contact information within the provider's possession or control, including both technical information and nontechnical information included in the contract for digital advertising services.

(b) There shall be a rebuttable presumption that a user-consumer is located in this State if the user-consumer contact information associated with a device or account on record with or available to a provider indicates an Illinois home address, an Illinois mailing address, or an Illinois internet protocol address or other user-consumer data showing "place of primary use" in Illinois as defined in the Mobile Telecommunications Sourcing Conformity Act. The burden of proving that a user-consumer is not located in this State is on the provider. For administrative ease, a provider may create reasonable categorization standards to use in analyzing user-consumer data to determine if a user-consumer is located in Illinois; however, its reliance on such standards does not alleviate the provider's burden of proof.

(c) Business entities that are part of a controlled group of corporations as defined in Section 1563(a) of the Internal Revenue Code shall be treated as a single entity for purposes of meeting the definition of a provider under this Act.