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-- Google AdWords
---- When Does Google Consider a Click Invalid?
Seb7 - 1:17 am on Mar 12, 2009 (gmt 0)Thread source:: http://www.webmasterworld.com/google_adwords/3867488.htm
I believe if the user had clicked 'back' to the same page it would not double charge you. If the user Searched again using the same keywords you would get charged.
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