California Elections Code Section 342

Proponent or proponents of an initiative or referendum measure means, for statewide initiative and referendum measures, the person or persons who submit a draft of a petition proposing the measure to the Attorney General with a request that he or she prepare a title and summary of the chief purpose and points of the proposed measure; or for other initiative and referendum measures, the person or persons who publish a notice or intention to circulate petitions, or, where publication is not required, who file petitions with the elections official or legislative body.