MI HB4455

Prohibits knowingly altering, removing, or obliterating firearm identification marks or serial numbers on firearms.

Requires all firearms and firearm frames or receivers manufactured, assembled, sold, or transferred in Michigan to contain valid firearm serial numbers.

Prohibits importing, purchasing, selling, or transferring firearm precursors unless they are classified as firearms under federal law and contain valid serial numbers.

Requires all firearm owners to possess firearms with serial numbers on the frame or receiver, effective 1 year after the bill's enactment, with penalties ranging from misdemeanor (first violation: up to 90 days imprisonment or $100 fine) to felony (subsequent violations: up to 2 years imprisonment or $1,000 fine).

Provides exemptions for antique firearms, law enforcement, federally licensed dealers and gunsmiths, military personnel, individuals turning in firearms to authorities, nonresidents traveling through the state, and new residents with a 90-day compliance period.