Used Canon 70-200 F/2.8 IS II, no date code, please help

I am looking at a used Canon 70-200 F/2.8 IS II and did not see the date code, is this normal? Is there any way to tell if it is a grey market lens over US? I was told it was bought at a US shop in Portland, OR. I don't really need the lens but the price is so tempting that even if I don't like the lens I can resell and make money, what do you think? I have looked at the lens and it is in perfect condition, no scratches anywhere.

This might help you: http://www.the-digital-picture.com …ses/Canon-Lens-Aging.aspx

Thanks, that helped. I ended up buying the lens, a no lose situation. I will resell if I do not want to keep it.

If the lens is perfect why does the date code matter to you?

If i was keeping this lens for a long time it personally would not matter to me, I tend to switch up my lenses often. For resale it seems that newer the lens the better value it has to others.