Thursday Google announced support for the "canonical tag" which is essentially a tag to tell Google and the other two search engines which version of a url you want crawled or indexed. In theory, this should help with duplicate content issues, but is this something you want to try? Read their full blog post here. Why are they doing this? Well, by now we've probably all heard Eric Schmidt call the internet a cesspool and we all know about issues with duplicate content. If I understand this correctly, Google is trying to take steps to clean up some of this duplicate content, and asking the public for help. Why you should consider doing it I'm going to jump right into the "human reviewing" factor. Forget about the technical side for a minute. Ostensibly by creating this tag, you're telling Google what content to grab, and you're being somewhat transparent as a webmaster and letting them know you aren't trying to game the system with doorway pages and multiple entry points. To the human reviewer, you are saying "Here is the page I want you to look at, and the other pages are duplicated beyond my control". At least that's one theory. From a technical standpoint, you're cleaning up their index of your page, and weeding out any duplicate content, which could make your remaining pages rank much better. Why you should consider not doing it Again, from the human reviewer standpoint: do you really want to let Google know you're trying to SEO your site? Google has said time and time again, Make pages primarily for users, not for search engines. So in way, this goes against their own code, and do you want the human reviewers to know you're doing SEO on your site? If the reviewers start searching for sites who are adopting this tag early, do you want to come up on their radar? That's a question you have to ask. From a technical standpoint, why do you need this tag anyway? You should be working hard to prevent duplicate content on your own, and not need this tag. Duplicate content is something that's under your control, and something you should have a handle on if you're concerned. If you're using some sort of CMS or other software on your site, is the time or money you're going to spend implementing this tag into your pages worth more than the time you'd spend fixing the problem in the first place? Another good use for this tag I have another good suggested use for this tag that's a little outside the box. If the implementation of this tag goes smoothly, you could use it to your advantage. Right now, if you were to go out and buy 20 domains with established traffic, and funnel them all to your homepage, you'd get penalized good. But this tag could help you do that. Let's say you are working on methods of acquiring traffic that have nothing to do with Google (I know, I know but it's possible)? This tag could help let them know you aren't trying to game them. You could buy different urls for marketing purposes, and point them to the same site without penalty. If you have a domain that doesn't quite fit in with your marketing, you could go buy one that does, and point it. Or, if you have a section of your site that could almost be another domain in itself, you could point a domain to it, for your offline marketing and not be penalized. This is all theory, I don't know for sure if you would be penalized for it, but it would be a nice side effect of this tag that I would like to see. Conclusion In the end, its your decision whether to implement this tag, and I hope I've given you some things to think about before doing so. Personally, I'm going to wait it out for a while and see if I can get a little more information before making a decision. We'll see how it goes. What do you guys think?
Non issue to anyone already using Google Webmaster. Google is just creating more work to try and get webmasters to believe they are the only game in town. I see no real advantages to this tag.
I see the primary advantage for shopping cart sites that do not already have SEO friendly URL's and as an alternative to a robots.txt block. i.e xyz.com/prod-cat-brand , xyz.com/cat-prod-brand , and xyz.com/brand-cat-prod might all contain the same content. This will make it easier for a site owner to let Google know they are not creating duplicate content, pick a page as their primary one, and still allow users the ability to find a site's products in multiple ways.
yes, i ran into it and think it would solve the confusion around onsite duplicate content with multiple tags for one single post. u made a commnet on this here
Hmmm I am right when I think I heard Matt Cutts say this tag can ONLY be used on pages within the same domain? In which case... doesn't this make it useless for one of the techniques the OP mentioned above? Namely gateways? Just a thought... I may very well be wrong of course! I have not really had much time to look into this as yet! - Anyone know the answer? - OP, you know? would be good to find out I guess!
sounds a little complicated and I really doubt if they are going to be able to solve this issue anyway.
I don't know if I buy it just yet either. I'm usually not so skeptical, but I think we're fine w/o it... there are ways around dupe content.
Would this new tag be placed "around" specified text, or just the top of the page you're favoring? I guess it beats putting no-follow, no-robots all over the place.
I don't think everyone needs to jump on board and start using this tag so quickly. Remember that Google takes into account that the majority of sites are not designed for SEO purposes, and therefore any webmasters who aren't SEO focused most probably will not know of this tag (just like with the nofollow).
I don't know the definitive answer for this. As of this time, I use a robots.txt for any gateway pages to avoid penalties, but I was just suggesting this as a possible solution as well. I'm not sure, but you may be right, if it only works on pages on the same domain it wouldn't work.
Although this might be useful in some situations, as you mentioned it could alert Google to the fact that you are trying to SEO your website. It also won't prevent duplicate content issues on different domains (and would be abused / misused if it was) so the tag probably has a very limited usefulness. Huge sites such as Wikipedia might benefit from this tag though.
If it is just for minor page changes why not just use the old noindex meta tag on one of the pages you don't want to get indexed? This new tag seems worthless! Read the freaking blog, it clearly says the tag is to be places in the <head> section.
If you watch this video: http://www.webpronews.com/topnews/2009/02/15/canonical-tag-announced-googles-matt-cutts-interviewed Matt does seemingly state that it is only for a single domain, and won't work for cross domains... I think, from what he is saying, they do it like that to avoid people hacking others pages, and sending the 'juice' to them! - Hope that clears it up! I must say though, I liked your post... threw up a few questions into the air
I think this will really going to help for clearing up duplicate content from their datacenters? And it will be helpfull for those webmasters who work really hard for orignal content?
so confusing...we already has a solution like robots.txt, nofollow tag it does not seems too beneficial.
No prob. I love this place, and I hope we can all share info, and help each other succeed. Yeah, that makes perfect sense now that I think about it, people could put tags in for sites they don't own, so that would make perfect sense for google to ignore them. I guess the robots.txt is still the way to go.