Google is showing adverts that you might not realise. You need to check these options, since Google have changed them without notice and have been charging advertisers for years for adverts the advertisers did not ask for.
Broad Match
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Originally, broad match meant all words had to be in the search term. In any order. Other words could be in the search string. Their example is "tennis shoes".
That meant a match against:
* buy tennis shoes
* tennis shoe photos
* running shoes
* tennis sneakers
Now it matches:
* tennis
* shoes
The difference between bidding on tennis and shoes as two different keywords and as one broad match? Seems to be no difference but they have sneaked this one in.
Broad match is now very dangerous. Use phrase and exact wherever possible.
[http://support.google.com/adwords/bin/answer.py?hl=en&answer=6100]
Targetting
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More important is targetting. They have changed the targetting from location to "search intent".
If you are a French company selling only to the French people, you have your adverts location targetting set to "France" and that should be fine, yes? No, it isn't.
Anyone searching for your search terms plus "france" or "french" in their search term may see your advert.
You think you targetted France, whereas you may be charged for clicks for people from Pakistan or Australia, even though there is no chance of a sale to that location!
This can be turned off:
* Go into your account online (AdWords Editor doesn't show the options!)
* Click on the campaign and choose the "Settings" tab.
* Click on "Advanced location options" and change the settings in there to target by physical location.
[http://support.google.com/adwords/bin/answer.py?hl=en-GB&answer=1722038&from=189075&rd=1]
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Personally, I think this is disgusting way to do business. No wonder their share price and profits keep rising but it seems to be more through dishonesty rather than good business practice in these cases.