In order to exclude specific searches from seeing AdWords ads, negative keywords are required. For example a company selling a Windows email application bidding on the phrase “email software”, might consider using the following negative keywords:
-mac
-apple
-os x
-free
-freeware
A person searching for “email software for mac” or “free email software” wouldn’t see the ads.
However, the content network functions quite differently from the search network; the main difference being that no search is carried out. Ads are displayed based on Google’s interpretation of your keywords and the page in question.
Let’s revisit the example. A company bids on the phrase “email software” and uses the above negative keywords. Will the ads be displayed on pages that contain the phrases, “email software for mac” or “free email software”?
Maybe.
Here is how Google explain the situation:
“If you add negative keywords to an ad group with placements, your negative keywords will behave as they have in the past for keyword-targeted campaigns on the Content Network. That means your ads will be less likely to appear on placements about the negative topics you’ve entered.
For example, suppose you select five different gardening websites as placements, then add the negative keyword -roses to the ad group. In that case, your ad may appear on any of the five websites, but it will be less likely to appear on pages of those websites that have to do with roses. In this case, your ad may still occasionally appear on placements about roses, depending on other keywords you have chosen for the ad group. Because groups of keywords work together on the Content Network, negative keywords are not as precise there as they are on search.”
Pay careful attention the wording: “less likely to appear” is more than a little vague, and also means that it is out of your control.
The conclusion? The negative keyword list on a content network campaign appears to be little more than a suggestion.
