Google Planning To Add New "Unavailable After" META Tag

Dan Crow, director of crawl systems at Google, has said that Google is releasing a new META tag named "unavailable_after."

The "unavailable_after" tag will allow you to tell Google when Googlebot should no longer crawl that page. This tag comes in handy when you have a limited time offer promotional page, and on this page, the promotion will expire on a specific date. By using the "unavailable_after" tag, you can tell Google that they should not crawl this page, after the promotion expires.

But Google has not yet revealed the date for the actual implementation of this tag.