Should I block robots from URLs containing query strings?

[ShearingsGroup]

I'm about to block off all URLs that have a query string using robots.txt. They're mostly URLs with coremetrics tags and other referrer info. I figured that search engines don't need to see these as they're always better off with the original URL.

Might there be any downside to this that I need to consider?

Appreciate your help / experiences on this one.

Thanks

Jenni

[anthonydnelson]

The downside to this would be if someone linked to the page with the query string, the search engines wouldn't crawl the page and flow link juice properly to the rest of your site.

Other options:

1. Use Google and Bing WMT to ignore those parameter query strings.

2. Make sure the canoncial tag is on those pages, pointing back to the version without the query string

3. Try to pass referrer info behind the scenes if possible

[kchandler]

Instead of blocking them with robots.txt (which isn't very effective), try using the canonical tag instead.

For instance, a URL like this:
http://wwww.testdomain.com/page.html?utm_source=Google&utm_medium=Banner&utm_campaign=Campaign

You could add this canonical tag in the head:

With this solution you don't have to worry about losing quality links OR having your query tracking show up in any of the major search engines.

Cheers- Kyle

[ShearingsGroup]

Thanks for your suggestions. I've already got canonical tags on every page, but they're not all being adhered to and lots of URLs with query strings are still getting organic traffic.

Passing referrer info behind scenes isn't an option with Coremetrics I don't think. Is it?

Interested to know more about number 1 though. How would you do that in WMT other than blocking with robots.txt?

Thanks