Simon, the seller can keep a record of what they have sold simply by recording the serial number somewhere, they don't need to keep the warranty card.
Carl - Certainly with Nikon lenses, you get an international warranty from Nikon - it matters not where in the world you purchased the lens, Nikon will deal with warranty claims for 1 year. In fact Nikon will 'make adjustments' (e.g AF calibration) under their warranty, whereas HDEW cover only manufacturer defects, therefore they are providing less of a warranty.
I just don't understand why they remove the warranty cards from lenses......
The explanation from HDEW was :
'For the warranty on the lens it does not come with a Nikon warranty card as they are country specific. We import the stock from outside of the UK so the Nikon card would be invalid. For the 1 year warranty on the lens you just need to keep hold of your invoice which is your proof of UK purchase.'
This is patently wrong - Nikon lens warranties are international - the warranty is NOT invalid......
The following is from the Nikon UK website :
International Warranty
This applies to conventional equipment (lenses, film based cameras, Speedlights)
• Your Nikon equipment is guaranteed against any manufacturing defects for one year from the date of purchase.
• The warranty card is issued only at the time of original purchase; it is non-transferable.
• The warranty card must be presented to the Nikon Service Facility before any repair can be made under warranty.
• Establishing the original purchase date should be made by the original consumer purchase via the sales slips, or other evidence.
Here is a link to the page :
http://www.europe-nikon.com/en_GB/service_support/Support_2_Warranty.page?lang=
This is very different to what they say about the Warranty on 'Digital Imaging Products' - which is a local warranty and ONLY valid in the listed countries.