Cal. Gov. Code § 25207.1
Any ordinance adopted by a board of supervisors requiring any person who represents a corporation, firm, association, organization, or person other than himself in attempting to influence any action to be taken on a county decision by a board of supervisors or any county board, commission, committee or officer, to register or to disclose any information concerning such representation including, but not limited to, compensation received or expenditures made in the course of, or incidental to, such representation, shall be enforceable within the incorporated as well as the unincorporated area of the county. The term "county decision" shall include any decision, or any recommendation as to a decision, concerning any matter, whether legislative, administrative, or quasi-judicial, which is pending before, or may be submitted to, the board of supervisors or any county board, commission, committee, or officer. Nothing in this section shall be construed to authorize a board of supervisors to require the registration of, or disclosure by, members of the State Bar of California in the performance of a service which lawfully can be performed only by an attorney licensed to practice law in the State of California.
Ca. Gov. Code § 25207.1