An important question that may pop up in the mind of a person involved in a search engine optimization campaign is “Is it okay to add a nofollow tag to a banner ad?” However, before moving straight on to the answer to this question, here’s a little introduction regarding the no follow tag and Google’s approach to no-follow links. The no follow tag is used with outbound links with the intention of not passing the page rank weight or PR to another site. It can reduce the effectiveness of spam and enable search engines to provide results uninfluenced by spam.
Generally, Google does not follow nofollow links, meaning that it does not transmit anchor text or PageRank across these links. However, it must be noted that there is a possibility of the target pages appearing in the Google index if: The URL submission to Google is in a sitemap Other websites link to the target pages without utilizing nofollow Now, coming to the answer to the question. Most banner ads are sold through advertising networks and exchanges which are not happy to have bots hampering their click counts or crawling their banner ads. So, these networks and exchanges already block out bots.
So, if you’re utilizing any typical advertising banner ad package, you don’t have any cause for concern. The reason is that most of the time there will be situations of blocks by robots.txt, and of not being really followable by search engines. If you’re selling a link yourself directly, and the difference here is of a text link versus an image link, and if a person has specifically paid for it, it would be a good idea to place a nofollow tag on the link irrespective of whether it is or isn’t an image link. Here also however, you don’t have much cause for concern. Google expertly handles the usual banner ad and other aspects, so that it does not affect PR. In conclusion, it should be mentioned that this blog only talks about Google. Keep in mind that other search engines may have a different approach when it comes to nofollow tags.