Serial numbers and PIX on the Montblanc pens
The Issue of Serial Numbers and the PIX Trademark on the Montblanc pens
Montblanc introduced serial numbers in 1991 in some sort of attempt to counter the replica/counterfeit market. This has not been particularly effective.
In general, all Montblanc pens made after 1991 should have a serial number, but remember that there are still a considerable number of used pens that date from before that, so lack of a serial number may mean only that it is an older pen.
The font of the serial number has changed at least once; the early ones (such as a 1991 146 fountain pen) is block-lettered, while current ones use a font that resembles the computer-readable numbers in a personal check. I am not sure when the switch occurred.
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| Initial serial number font type |
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| Current serial number font type |
To make matters more complicated, Montblanc does reuse serial numbers (they are issued randomly with no discernable pattern), so two pens with the same serial number could still be genuine. It is likely that they would be different models and separated by many years in time, though.
Also, they do not keep any database of serial numbers except for the limited edition pens.
Around 1997, Montblanc introduced the "Pix" mark as a further anti-counterfeiting feature. Often you will find this on the cap band as well as a much less obvious place: the underside of the clip. However, the presence or absence of this mark does not mean the pen is a fake or a genuine product; many modern counterfeits dutifully include the Pix mark as well, including on the underside of the clip (for the higher-quality fakes).
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| PIX mark on the underside of the clip |
Placing the PIX mark on the underside of the clip is the more common option in these pens; placing it on the cap band is a more recent thing (apparently some time in the mid 2000s) and only applicable to some pen models.
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| PIX mark on the cap band |