The only place that would have come from is from Google. Google ads use 2 methods to deliver ads – 1) They will look at the context of the page, specifically the text and match ads to keywords or 2) They will match ads to your recent browsing history – which does of course bring up an interesting scenario 🙂
Anyway, I can block individual advertisers through our account with Google but only if I know which website that ad links too. If anyone sees it again can you hover over it with your cursor and see which website it wants to send you to? I’ll then be able to block it.
Cheers
Mark