Cal. Penal Code § 484i

(a) Every person who possesses an incomplete access card, with intent to complete it without the consent of the issuer, is guilty of a misdemeanor. (b) Every person who, with the intent to defraud, makes, alters, varies, changes, or modifies access card account information on any part of an access card, including information encoded in a magnetic stripe or other medium on the access card not directly readable by the human eye, or who authorizes or consents to alteration, variance, change, or modification of access card account information by another, in a manner that causes transactions initiated by that access card to be charged or billed to a person other than the cardholder to whom the access card was issued, is guilty of forgery. (c) Every person who designs, makes, possesses, or traffics in card making equipment or incomplete access cards with the intent that the equipment or cards be used to make counterfeit access cards, is punishable by imprisonment in a county jail for not more than one year, or by imprisonment pursuant to subdivision (h) of Section 1170.