The Incredible Disappearing Web Ads

First came adware, sparking online publishers’ ire for its ability to deliver competitive ads next to or on top of a site’s existing ads without the user’s knowledge. Now there’s Greasemonkey, a Firefox browser extension (plug-in). The extension enables Firefox users to share scripts that change the way particular Web pages appear to users who have installed the scripts. Most are written for a specific site and perform a specific function. Of the changes these scripts facilitate, ad elimination is one of the greatest threats to media buyers.

If you were to visit an article on CNN using Firefox with the Greasemonkey extension, CNN’s banner and left nav bar are pushed to the bottom of the page. The ads to the far right are also at the bottom. Only text ads and the article itself remain.

Adware gives users no control. Greasemonkey gives users complete control. These scripts are written by an ever-expanding community of programmers and designers who want to view Web pages, well, the way they want to.

Don’t like navigation? Change it! Sidebar too wide? Shrink it! Amazon pricing in the wrong currency? Easy fix! The list of scripts is extensive. And, it grows organically. Developers can easily post them to a wiki (define).

As online media buyers, we should be concerned if our ads are blocked. When a user opens a page with Firefox and the ad-blocking script, the page and the ads are at first fully served. Within seconds, however, the ad-blocking script strips out or relocates the ads. The script identifies the ads by their class attribute, “ad.” Ads assigned a different class attribute or injected with a JavaScript onload event handler (define) survive the script.

Yet the publisher counts the stripped-out ads as served, even if they couldn’t be viewed. The development community is working on a method of running these user scripts early in the page-request cycle. This would completely eliminate the ad request and, therefore, the false data. For now, Greasemonkey scripts can lead to over-reporting served ads, however small that percentage may be.

Though many of these scripts were written to eliminate ads on Web pages, publishers do have recourse. A code has been written to block Greasemonkey scripts from altering Web pages. There are also rumblings of potential lawsuits.

Greasemonkey can wreak havoc with fee-based or registration-only online sites. Some scripts allow users to view restricted content without logging in. and have already fallen prey.

Greasemonkey isn’t the first or only ad-blocking mechanism out there. Both Firefox and Internet Explorer have pop-up suppressors. A quick search reveals no fewer than 77 ad-blocking software downloads.

If Greasemonkey rides a similar tide of organic growth as Firefox, it’s noteworthy. The development community feels Greasemonkey won’t cause much damage; they remind us anyone who goes to these lengths to block ads is very unlikely to actually pay attention anyway.

There’s some good in these scripts. If a publisher wants a free critique of his site’s unpopular weaknesses, he can just review the Greasemonkey user scripts available for his site. Usability studies typically cost thousands of dollars, so these scripts are a potential cost savings. A little constructive criticism can go a long way. The cleverest publishers would encourage Greasemonkey developers to create a script to display their sites with the ultimate balance of content and advertising. ` up to that challenge?

A special thanks to Jeremy Dunck, publisher of Greaseblog for his contributions to this column.

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