How do you recognise the authenticity of a Montblanc Starwalker Rubber ballpoint, and what does the position of the serial number say about the model year?

On the Starwalker Rubber two variants of serial-number placement exist: on older models the number is on the clip at the height of the clip ring; on newer ones directly on the clip ring. Both variants are original-typical and no counterfeit indicator. A discrepancy between the serial number on the pen and in the Service Guide is mostly due to an accidental enclosure of the wrong guide by the seller and should be enquired with the seller. A systematic attribution of the serial number (e.g. starting with XD) to a concrete production year is not known; only Montblanc customer service can give information.