Ever since one of my sites got spanked by Google in late June I have been thinking awful long and awful hard about how Google spots paid links and devalues or discounts them. I have been trying to find out what a perfect link is and here are a couple of ways a link is not perfect: 1. When a link suddenly appears in a content page that is already indexed in a Google. Think about it; how often do you go back and add a link to an article you wrote 6 months ago? This method of buying links is becoming more popular because people think it is undetectable but it is not I assure you. Google knows what a page looked like when it first indexed it. If it has remained that way for a certain period of time then why would it suddenly have a link in it? Google knows why - someone has paid for that link to be there. Now I'm not talking about all pages here because obviously homepages change all the time (as do link pages and things like that) but there has got to be some logic that can route out these links. The time frame between a page being indexed and a link appearing may be a factor - if the link shows up a week after indexing is this too long? 2. Secondly I have thought about buying blog posts on large networks. Now this is something I have never done but I have bought posts on smaller networks of 3 or 4 blogs but this is just as bad. Let me explain; since most people who opt for blog packages will buy the full deal it means that these 3 or 4 blogs all have links to the same sites. If there are 26 people who have bought the package then it means 26 posts on each blog each with links to the same 26 sites. Now again, this is not necessarily the case since people might buy a package and then use different posts to promote different sites but a lot wont, they will have the same link (albeit with different anchor text) on all the posts. Surely this network of blogs is selling links and so chances are they will get penalised and links devalued. So what's the solution? Well my opinion (and that's all it is so don't have a go at me if you disagree) is that you need to avoid blog networks for the most part. I do still use some high quality, small networks but will choose just a couple of blogs from them. I will ask for the posts to be published a few days apart to make it seem more natural. I try not to buy links within an article that already exists and is indexed. I try not to use networks where it is obvious the posts have been bought as a package (i.e. where the link are the same). You can spot this just by looking at the blogs in question. Try and go for the high quality blogs only as they will provide more value in the long run. When buying links, ask the site owner if they wouldn't mind hosting an article on their site instead with a link to your site. Then wherever the direct link would have been placed ask that it be pointed towards your article instead. This way you will end up with a more natural looking backlink profile. Just my 2 cents. Feel free to comment if you have any questions, things you disagree with.