Related:Search for Site-A and Site-Z shows up

An interesting find.

[McMohan]

For a related:www.domain.com search in Google for Client-A, our other client-Z shows up, whose relevancy is as distant as is Z from A.

1. Well, neither site A or Z give a link to each other.
2. No duplicate content between the 2.
3. The businesses they are in are entirely different.
4. Hosted on different servers.
5. Don't use any common design template.

Then how does Google know they are related, atleast as our clients, which seems to the only common factor.

My guess -

They both may have been listed in few sites that we usually get links from. (Mind you, they are not listed on same page, as they both are in very different fields.

Can't think of any other reason. Please provide your inputs.

[steveb]

That's how sites get related, common links.

[McMohan]

Steve, agreed. I thought it may be so, if the sites were listed in a bunch on a single page on different sites. But these sites aren't listed on a single page.

So, will Google assume they are related even if they are listed on any page of the site and it is a "common site" factor? Also, apart those 2 sites, there are many other sites listed and those 2 sites have inbounds from many other sites which don't link to both the sites from them. So, there may be a percentage of "common sites" that link to both the sites to raise flag as related?

I guess this interprtation will be helpful for those who don't want to wait for links coming naturally ;-)