Originally Posted by
helosc
The route I remember 100% is Copenhagen to Hamburg on a DB train, tickets always bought online at DB (self print). I have to show the credit card first on Danish soil where they merely look at it and check the last four digits. And then again on German soil where they actually scan the card.
As for the internal German routes, I seem to remember having to show my card but can't swear to it.
On the other hand I have two upcoming train trips: Berlin - Dresden and return.
On those it clearly says that the tickets are only valid for me personally together with the credit card. And that the ticket control will scan the card and the barcode of the tickets.
For the DB you can set up a identity document in the online profile. This can be a passport, drivers license, national ID card or some credit card (not necessarily the one you paid with). If you buy a ticket logged into the profile you have to produce that identity document.
If you just buy a ticket without being logged in they might want to see the card the ticket was paid with.
Anyway, traveling on the DB a couple of doZens time a year I had to show the card just once.