One of the major issues plaguing search engines right now is the growing list of web documents available online. While no exact numbers are available, there are billions of search results to sort through. But, they can’t all be relevant both on material content and time — can they?
Of course they’re not, and Google is hoping to solve this problem through the adoption of the unavailable_after META tag.
What is unavailable_after?
The unavailable_after META tag is a simple META tag that can be used alongside others in the HEAD of an HTML document. The unavailable_after tag informs the crawling robots and spiders of an expiration date for the content. In other words, if you tell the bots that a page is “unavailable_after” tomorrow’s date — they should no longer index it or provide it in the search results following tomorrow.
How can unavailable_after be used?
unavailable_after can be used in a number of ways, with the most obvious being for testing and time limited materials. Let’s say for example that you run a web site that deals with seasonal items that are updated frequently. What good would there be to having pages from 4 years ago indexed on your site then, if you have more up to date, more seasonally appropriate, and more advanced products for sale today?
The unavailable_after tag allows webmasters to control the amount of data indexed, as well as set some precedents on how to handle the data that engines are pulling and providing in the SERPs.
How Will unavailable_after impact SEO Results?
The unavailable_after should have a tremendous effect on SEO and general site rankings. The ironic part is that when Google adopts the unavailable_after with open arms, there will be little fan fare. On the surface, there really is no big deal.
But consider the following…
If you’re optimizing a web site and have content that never really expires, wouldn’t it be great to compete against less pages and less sites in the Google index? Of course it would! And that is precisely what the unavailable_after tag will allow. As more and more webmasters begin using the unavailable_after tags in their pages, fewer and fewer pages will be out there to compete against. As a result, you’ll be ranking higher and higher and gaining more authority in no time!
Sujan Patel is Director of Search at Single Grain, which specializes in Search Engine Optimization and Social Media Marketing