Using Canonical on home page

[halloranc]

Our home page has the canonical tag pointing to itself (something from wordpress i understand).

Is there any positive or negative affect that anyone is aware of from having pages canonical'ed to themselves?

[TomRayner]

Hi Casey

I have a "self-referring" (pointing to itself) canonical on all of my pages, if another isn't needed.  There's certainly no harm in doing so and I believe that there is a benefit to.

If your content is put up, is indexed first by Google and has the canonical tag on it - that is a really clear directive to Google/Bing that you are the originator for your content.  That means if someone comes along and steals/scrapes the content from your site, they are far less likely (in my opinion) to be successful in passing it off as their own (and therefore leaving you with a duplicate content issue).

In addition, having self-referring canonicals on pages future proofs you against any plugins/searches/features of your site that might generate multiple URLs from an original (think www.domain.com?searchquery.html if you have a search function on your site). Having a canonical will mean that Google will not index multiple versions of your URL, which might also result in duplicate content.  This also prevents attacks from people who try to brute force multiple versions of your URL to get indexed (ie sending spam links to www.domain.com?randomquery - it's very rare but I've seen it happen)

In short, I think self-referring canonicals are great idea - use them wherever you can.