California makes possessing a suppressor a felony
“Any person, firm, or corporation who within this state possesses a silencer is guilty of a felony and upon conviction thereof shall be punished by imprisonment pursuant to subdivision (h) of Section 1170 or by a fine not to exceed ten thousand dollars ($10,000), or by both that fine and imprisonment.”
California makes possessing a silencer a felony with a fine of up to $10,000, and federal registration does not change that. Section 33415 exempts only the law enforcement agencies listed in section 830.1, the military, on duty peace officers, and NFA registered dealers or manufacturers selling to those agencies. No permit exists for a private owner.