Is this duplicate content something to be concerned about?

[bfrl]

On the 20th February a site I work on took a nose-dive for the main terms I target. Unfortunately I can't provide the url for this site.

All links have been developed organically so I have ruled this out as something which could've had an impact.

During the past 4 months I've cleaned up all WMT errors and applied appropriate redirects wherever applicable. During this process I noticed that mydomainname.net contained identical content to the main mydomainname.com site. Upon discovering this problem I 301 redirected all .net content to the main .com site. Nothing has changed in terms of rankings since doing this about 3 months ago.

I also found paragraphs of duplicate content on other sites (competitors in different countries). Although entire pages haven't been copied there is still enough content to highlight similarities. As this content was written from scratch and Google would've seen this within it's crawl and index process I wanted to get peoples thoughts as to whether this is something I should be concerned about?

Many thanks in advance.

[PoweredbySearch]

Might still be a good idea to add a rel canonical tag to your .com domain.

• Marc.

[eyepaq]

Did you use the main term in the anchor text a lot ? (exact match or in some combinations ?)

[Saijo.George]

if you do make sure it is  cross-domain rel="canonical"

http://googlewebmastercentral.blogspot.com.au/2009/12/handling-legitimate-cross-domain.html

If you have 301ed it I would not worry about the .net dupes