California Code, Elections Code - ELEC § 2032

Except as provided in this article, if a person has more than one residence and that person has not physically resided at any one of the residences within the immediate preceding year, there shall be a rebuttable presumption that those residences in which he or she has not so resided within the immediate preceding year are merely residences as defined in subdivision (c) of Section 349 and not his or her domicile.