Cal. Public Contract Code § 2204

(a) A public entity shall require a person that submits a bid or proposal to, or otherwise proposes to enter into or renew a contract with, a public entity with respect to a contract for goods or services of one million dollars ($1,000,000) or more to certify, at the time the bid is submitted or the contract is renewed, that the person is not identified on a list created pursuant to subdivision (b) of Section 2203 as a person engaging in investment activities in Iran described in subdivision (a) of Section 2202.5, or as a person described in subdivision (b) of Section 2202.5, as applicable. (b) A public entity shall not require a person that submits a bid or proposal to, or otherwise proposes to enter into a contract with, the public entity with respect to a contract for goods or services of one million dollars ($1,000,000) or more to certify that the person is not identified on a list created pursuant to subdivision (b) of Section 2203 as a person engaging in investment activities in Iran described in subdivision (a) of Section 2202.5, or as a person described in subdivision (b) of Section 2202.5, as applicable, if the person has been permitted to submit a bid or proposal to the public entity pursuant to subdivision (c) or (d) of Section 2203. (c) (1) Subject to paragraph (2), the certification requirement described in subdivision (a) applies on and after June 1, 2011. (2) A person that is a financial institution shall not be required to certify as provided in subdivision (a) until July 1, 2011. For any subsequent list created pursuant to subdivision (b) of Section 2203, a person that is a financial institution shall not be required to certify with respect to that subsequent list until 30 days after that list becomes available, but shall certify with respect to the immediately prior list for those 30 days.