SEO impact on a multi-site environment with some similar content

Question

I have a network of sites (70+) that use subdomains like this for a national site and regional branches:

• example.com
• atlanta.example.com
• chicago.example.com
• dallas.example.com

Each of them have an About page that starts off with a short intro paragraph regarding the regional site and then the rest of the page is a canned, nearly identical description of the overall firm and its services.

• example.com/about
• atlanta.example.com/about
• chicago.example.com/about
• dallas.example.com/about

My question is about the impact this system will have on SEO. Will search engines consider these About pages duplicate or spammy content because they are similar? We do need to present this info to our users on a regional level, but it doesn't make sense to write 70+ different about pages that are trying to give the same info about the overall firm and some unique info about the regional site.

Answer 1

The worst that would occur is that the sub-domain about pages will be filtered out of the search results. I doubt it would be considered "spammy" to invoke any type of "penalty".

Google has the broad definition of duplicate content as anything that is:

substantive blocks of content within or across domains that either completely match other content or are appreciably similar

...which it sounds like your content is.

I'd consider an alternative approach - using the single page (example.com/about), making it the canonical version (using rel=canonical) and then from each subdomain linking to that page with a cookie/tag/query-string/insert-your-method-here passing what sub-domain (or use a referrer check) the request is coming from to dynamically insert the relevant non-canned content.