How do they authenticate a "Banksey"?

Question: How do they authenticate a "Banksey"!?
Best Answer - Chosen by Asker:

it would be on his website

http://www!.banksy!.co!.ukWww@QuestionHome@Com

That's a good question i suppose if he has a signature next to his graffiti art then you know its the original, heck i could be Bansky now you never know!Www@QuestionHome@Com

i dunno!. all i do know is "Banksey" is a group, not a single man!.Www@QuestionHome@Com

It'll be easily recognizable as crap!.Www@QuestionHome@Com

His manager claims it!.
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