California Code, Elections Code - ELEC § 9265

The petition shall be filed with the elections official by the proponents, or by any person or persons authorized in writing by the proponents.  All sections of the petition shall be filed at one time, and a petition section submitted subsequently may not be accepted by the elections official.  The petition shall be filed (1) within 180 days from the date of receipt of the title and summary, or (2) after termination of any action for a writ of mandate pursuant to Section 9204, and, if applicable, receipt of an amended title or summary, or both, whichever comes later.