Illinois Code § 2

§ 2.

Employee rights to inventions - conditions). (1) A provision in an employment agreement which provides that an employee shall assign or offer to assign any of the employee's rights in an invention to the employer does not apply to an invention for which no equipment, supplies, facilities, or trade secret information of the employer was used and which was developed entirely on the employee's own time, unless (a) the invention relates (i) to the business of the employer, or (ii) to the employer's actual or demonstrably anticipated research or development, or (b) the invention results from any work performed by the employee for the employer. Any provision which purports to apply to such an invention is to that extent against the public policy of this State and is to that extent void and unenforceable. The employee shall bear the burden of proof in establishing that his invention qualifies under this subsection. (2) An employer shall not require a provision made void and unenforceable by subsection (1) of this Section as a condition of employment or continuing employment. This Act shall not preempt existing common law applicable to any shop rights of employers with respect to employees who have not signed an employment agreement. (3) If an employment agreement entered into after January 1, 1984, contains a provision requiring the employee to assign any of the employee's rights in any invention to the employer, the employer must also, at the time the agreement is made, provide a written notification to the employee that the agreement does not apply to an invention for which no equipment, supplies, facility, or trade secret information of the employer was used and which was developed entirely on the employee's own time, unless (a) the invention relates (i) to the business of the employer, or (ii) to the employer's actual or demonstrably anticipated research or development, or (b) the invention results from any work performed by the employee for the employer. (Source: P.A. 83-493.)