California Code, Business and Professions Code - BPC § 10141

Within one month after the closing of a transaction in which title to real property or in the sale of a business when real or personal property is conveyed from a seller to a purchaser through a licensed real estate broker, such broker shall inform or cause the information to be given to the seller and purchaser in writing of the selling price thereof and in event an exchange of real property or a business opportunity is involved, such information shall include a description of said property and amount of added money consideration, if any.  If the transaction is closed through escrow and the escrow holder renders a closing statement which reveals such information, that shall be deemed compliance with this section on the part of the broker.