when you look at the destination url of adwords ads (via view source in a serp listing) many (but not all) of the urls for ppc listings have the query string '&usg=' appended, e.g.: &usg=AFQjCNHRaqqCpfsy9tzz_lJUqlqnc283cg Can anyone let me know what this relates to? I am guesing it is an adwords account setting of some description or even analytics related. It is just puzzling beacuse I see the majority of dest urls with it but some without. Thanks