When Paypal's official Web site no longer ranked #1 in Google on a search for "paypal," it was obvious that Google had become more aggressive in penalizing sites with "unnatural" backlink anchor text. Although high-profile Paypal example has since been rectified, thousands of webmasters are suffering consequences of not ranking for even their official company name, let alone their top keywords. It is important for search engine optimizers to understand both how anchor text penalties are being applied and how LSI ensures that anchor text variance will not dilute a link popularity building campaign.
Anchor Text Penalties
In past year, webmasters have found that aggressive link popularity building tactics that work well in search engines such as Yahoo! do not fare well in Google. Google has implemented several features to filter out sites that appear to have an unnatural backlink structure; one of these features seems to be specifically penalizing sites with unnatural backlink anchor text.
It has always been an SEO best practice to use descriptive anchor text in both external and internal links. But search engine optimizers have often focused on a single keyword phrase when choosing anchor text, especially if their topic has one keyword that receives vastly more traffic than any secondary keywords. Since good links are hard to come by, they do not want to "waste" any of those backlinks with anchor text that does not contain their main keyword.
The drawback to this approach is that it can be interpreted as unnatural by a search engine. A site with organic, passively-obtained backlinks will have a wide variety of backlink anchor text variations such as: "official site title," "keyword," "keyword synonym," "www.thesite.com" and even "click here." If vast majority of a site's backlink anchor text is simply "keyword," it is obvious to an algorithm that link popularity was not obtained organically.
Latent Semantic Indexing (LSI) Basics
Let's now touch upon myth I mentioned before, that if a backlink's anchor text does not contain your Web site's main keyword, its power is wasted. The concept of latent semantic indexing, which may be more fully implemented by major search engines in near future, will prove this myth to be false.