I don't know what is the relevance to the "mobile phones" search term of the content available on the mobile network 3's website but I do know they are accused by some members of the search engine marketing industry of manipulating Google's search engine rankings.

If you don't have any knowledge related to search engine optimization techniques and about the ways one can easily manipulate them, probably the single piece of info you need to know is that they are suspected of getting about 3.4 million websites to link to a domain they own (threestore.three.co.uk) using the anchor text "mobile phones".

Also, I don't know since when they hold the second position on Google in the search results you get when searching for "mobile phones" (you can check for yourself if you don't believe me) but the rumor seems to be right because, according to the short summary containing the 3.4 million links going to the 3 mobile network's domain the Yahoo search engine provides, some of the websites that have contained such links no longer contain them and others present them in the right bottom side of the page where not many users look.

That means they were put there just to be able to manipulate Google's search results and this fact could be a strong reason to ban the 3 website from the search engine's ranking system therefore being removed from the search results you will get for "mobile phones" when using Google.

This type of practices are not illegal by any means, but the thing that makes them not loved by the search engine companies is their sheer immorality. By using search engine manipulation one can actually alter the way search results are displayed, making some irrelevant websites for your search go even to the first page.

To better understand why nobody loves such practices read what Matt Cutts, a Google employee, has to say on this subject:

"SEO geeks may remember the SearchKing lawsuit regarding link selling that was filed in 2002 and dismissed in 2003. Or they may have read through our quality guidelines, especially the part that says "Don't participate in link schemes designed to increase your site's ranking or PageRank". Those people can probably guess that Google does consider buying text links for PageRank purposes to be outside our quality guidelines.

But for everyone else, let me talk about why we consider it outside our guidelines to get PageRank via buying links. Google (and pretty much every other major search engine) uses hyperlinks to help determine reputation. Links are usually editorial votes given by choice, and link-based analysis has greatly improved the quality of web search. Selling links muddies the quality of link-based reputation and makes it harder for many search engines (not just Google) to return relevant results."

You should understand one thing though: nobody is accusing directly the 3 mobile network of such a practice because, at the moment, they are only suspected of such dirty ways of gaining web traffic and, in consequence, more clients.