Multiple, Partial Redirecting URLs from old SEO company

[LeverSEO]

Received quite a surprise when I gained access to the Google webmaster account and saw 4 domains that are link to my clients domain and the number of links for each domain range between 10,000 and 90,000.

Come to find out this was a result of their former agency.  The business is very local central.  I will use the example of a burger place. They main site is burgers.com and burger places are listed by city and state.  Their former agency bought several domains like californiaburgers.com and duplicated the listings for that state on this domain.  You can view certain pages of the second domain, but the home page is redirected as are most of the city pages with 301s to the main burgers.com domain.

However, there are pages on the additional domains that do  not redirect, as they are not duplicated on the main domain so nowhere to redirect.  Google has only found four of them but looks like there could be at least 50.  Pages that are not redirected are indexed by the engines - but not ranking (at least not well).

There is a duplicate content issue, although "limited" in the sense that it really is just the name of the business, address and phone number - there is not much to these listings.

What is the best approach to overcome? Right now GWT is showing over 300,000 links, however at least 150,000 to 200,000 of that is from these domains.

[AlanBleiweiss]

Brutal honesty time.

You're in a very difficult position on this one.  From one perspective, the best practice would be to tell you all of those domains should be shut down, not even 301 redirects.  It's the only "ideal" clean-up of what could very well be deemed mass-scale spam.

However, doing so could literally wipe out a significant volume of existing SEO strength that comes from the links because there's just no way to know how those sites are or are not impacting the main site at this point.

Alternate option:

If there are pages on the rogue domains not on the main site, are those pages that "should" be on the main site when taking the "single site" approach?  If so, those should be moved and redirects set up.  And if that content doesn't really belong on the main site, those pages should be redirected to their parent home page or wiped out entirely.

In this scenario, you're communicating "there's only one site - it's the site we want ranking, and thus we've taken action to kill all the renegade content".

This is the option I would recommend if it were my client.

Except how can you determine all the other rogue domains out there? That would be important to the process.

I would personally also need to evaluate current organic search traffic to help decide what to do.  Is the total organic based visit count significant?  Or is it almost non-existent?  Because if it's almost non-existent, as painful as it might be to do so, I would opt for the first action - killing off all the rogue domains.

As drastic as it is, and as much as some SEOs would say "get what value you can from redirects", it really is the safest way, long-term to ensuring the site doesn't get slammed by Google. And if short-term or even mid-term rankings drop in that process, my position is still "I care most about long-term goals with sustainability and stabilization critical long-term elements.

Whatever you consider doing, I would also explain all of this to the site owner, and have them participate in the decision making process in a way you can be sure they first understand the issues and then that they have no ability afterward to blame you for anything that takes place due to past methods that were obviously ugly at best and reckless at worst.

I'd also love to hear what others here have to say about this and what they would recommend.