VEH § 10753

(a) Any person who removes, alters, or obfuscates any vehicle identification number or other unique marking that has been added to a catalytic converter is guilty of a misdemeanor.

(b) Any person who knowingly possesses three or more catalytic converters that have the vehicle identification number or other unique marking removed, altered, or obfuscated is guilty of a misdemeanor.

(c) This subdivision does not apply to either of the following:

(1) Any person who is removing, altering, or obfuscating a vehicle identification number or other unique marking in order to apply a new vehicle identification number or unique marking because the catalytic converter is being lawfully installed on a different vehicle.

(2) Any person that is disassembling, smelting, or otherwise permanently destroying a catalytic converter lawfully in their possession.