Totally an aside, but if you're in the US and there's a collections agency after you for a bogus debt, it's easy to make them go away: Send them a formal dispute letter under the Fair Debt Collections Practices Act and advise them not to contact you further. If they do anyway, you can sue them for punitive damages.
It's actually a pretty nice, common sense law. Note that if you intend to dispute the charge, you should move quickly: there's a 30 day limit from first notice.
This is an interesting piece of information, thanks! Up in Canada I have heard of stories where debt collectors will call a "John Smith", ask them for their DOB, and SIN, type that information into their debt file (which does not have this information) and make them pay. I wonder if there's similar legislation in Canada.
Good point. Though sending a certified letter disputing a debt to a first-party collections department isn't going to hurt you even if it isn't binding.
I doubt that there's a EU-wide norm for that yet, but in Germany, what you do is completely ignore anything the collection agency does by itself after you first tell them you think the claim is invalid. What you must not by any means ignore is the Mahnbescheid (a court notice of the claim) - reply to that immediately that you contest the claim. In most cases that will be the last thing you hear, since they'll then have to actually sue you and prove the validity of the claim to a court.