49 CFR § 565.13 - General requirements.
(a) Each vehicle manufactured in one stage shall have a VIN that is assigned by the manufacturer. Each vehicle manufactured in more than one stage shall have a VIN assigned by the incomplete vehicle manufacturer. Vehicle alterers, as specified in 49 CFR 567.7, shall utilize the VIN assigned by the original manufacturer of the vehicle.
(b) Each VIN shall consist of seventeen (17) characters.
(c) A check digit shall be part of each VIN. The check digit shall appear in position nine (9) of the VIN, on the vehicle and on any transfer documents containing the VIN prepared by the manufacturer to be given to the first owner for purposes other than resale.
(e) The VIN of each vehicle shall appear clearly and indelibly upon either a part of the vehicle, other than the glazing, that is not designed to be removed except for repair or upon a separate plate or label that is permanently affixed to such a part.
(f) The VIN for passenger cars, multipurpose passenger vehicles, low speed vehicles, and trucks of 4536 kg or less GVWR shall be located inside the passenger compartment. It shall be readable, without moving any part of the vehicle, through the vehicle glazing under daylight lighting conditions by an observer having 20/20 vision (Snellen) whose eye-point is located outside the vehicle adjacent to the left windshield pillar. Each character in the VIN subject to this paragraph shall have a minimum height of 4 mm.
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