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Hi Errol, Yep, these links all come from the same c-block. As Mary says, it's likely that Google is well aware that these sites are related. I disagree that that would automatically put you at high risk for a penalty, given that interlinking owned / managed websites is common practice, even amongst people who are not doing so for SEO purposes. Unless the network of sites appeared very manipulative, it is likely that the links would be discounted and no benefit passed between them rather than you being slapped with a bad penalty... however, nofollowing the links between each site and your hub site is the best practice when it is done to any extent / large scale, just in case this was viewed as manipulative. Since I do not know how many links / sites we're talking about here, I would certainly say that nofollowing these links would be the safe thing to do. Even if you were being super-sneaky with the hosting of these sites, disguising Whois information, making changes to your template, etc., Google is incredibly good at figuring out which sites are related to each other. They've been good at this for a long time, so it's always best to assume that they'll know about professional networks like yours and follow best practice with linking. Hope this helps! Jane