California Code, Civil Code - CIV § 1102.3

(a) In the case of a sale, as soon as practicable before transfer of title.

(b) In the case of sale by a real property sales contract, as defined in Section 2985, or by a lease together with an option to purchase, or a ground lease coupled with improvements, as soon as practicable before execution of the contract. For the purpose of this subdivision, “execution” means the making or acceptance of an offer.

(c) With respect to any sale subject to subdivision (a) or (b), the seller shall indicate compliance with this article on the real property sales contract, the lease, or any addendum attached thereto or on a separate document.

If any disclosure, or any material amendment of any disclosure, required to be made by this article, is delivered after the execution of an offer to purchase, the prospective buyer shall have three days after delivery in person, five days after delivery by deposit in the mail, or five days after delivery of an electronic record in transactions where the parties have agreed to conduct the transaction by electronic means, pursuant to provisions of the Uniform Electronic Transactions Act (Title 2.5 (commencing with Section 1633.1) of Part 2 of Division 3), to terminate the offer by delivery of a written notice of termination to the seller or the seller's agent. The period of time the prospective buyer has in which to terminate the offer commences when Sections Iand II, and, if the seller is represented by an agent in the transaction, then also Section III, in the form described in Section 1102.6, are completed and delivered to the buyer or buyer's agent. A real estate agent may complete their own portion of the required disclosure by providing all of the information on the agent's inspection disclosure set forth in Section 1102.6.