California Code, Business and Professions Code - BPC § 22395

(a) Information which at the time of disclosure is in the public domain.

(b) Information which, after disclosure, becomes part of the public domain by publication or otherwise, independently of any act or omission by the invention developer.

(c) Information which the invention developer can establish by competent proof was in its possession at the time of disclosure by the customer, and was not acquired, directly or indirectly, from the customer.

(d) Information which the invention developer receives from a third party; provided, however, that such information was not obtained in confidence by said third party, directly or indirectly, from the customer.

This duty of confidentiality includes the taking of reasonable steps by the invention developer to prevent disclosure of confidential information to third parties. This confidential relationship cannot be waived by a customer without an express written waiver by the customer of the invention developer's obligation of confidentiality, and no waiver shall be entered into until after the disclosures described in Section 22381 have been made.