Does linking my two sites together violate the quality guidelines?

Matt's answer:

We have a question from Tokyo, Japan. And the question is, “Suppose I have a site that covers fishing overall, site A, and I make another fishing site that solely focuses on lure fishing, site B. Does linking to A from B violate guidelines? I’ll make sure that both have high quality content, and I disclose that they’re both owned by me.” OK, so I’m going to answer exactly the question you asked, and then I’m going to tell why you’ll want to think about the broader picture a little bit as well. Just linking from A to B is not a violation of our quality guidelines. If you only have two sites, they’re thematically related, a person on A would be interested in B, then it makes perfect sense to link those two sites. The problem gets into when you don’t have two sites, but you have 50 sites, or 80 sites, or 150 sites. And then suddenly linking all of those sites starts to look a lot more like a link network, and something that’s really artificial, as opposed to something that’s organic. So if you really do have just a very, very small number of sites, you can count them on one hand and they’re all very related to each other, it can make perfect sense to link those together. It’s when you start to get a lot more sites, you know, you don’t need to 222 sites about car insurance, right? And it looks a little weird if you have, howdoigetmycarinsurance.net, and wheresthecheapcarinsurance.com, and I’m making these domain names up. So I’m not saying these particular site owners are bad. Maybe they’re great, who knows? But if you’ve got 222 different copies of that, usually you’re not putting as much work into each individual site. And so as a result, you’ll end up with shallow or superficial sites, lower quality content. You’re more likely to see doorways, or that sort of thing. So I understand if you don’t maybe want to have just a single site. Maybe you want to diversify, you want to have different sites. So as long as they’re related and it’s a relatively small number of sites, then it can make sense to cross link those two together. But what I wouldn’t do is just say, OK, well, that’s permission to take my entire link network of 1,500 different domains and cross link all those guys, because that can look pretty bad whenever users land on the page.

by Matt Cutts - Google's Head of Search Quality Team

Original video: