So what --in short-- does Google consider linkspam:
Artificial link schemes, paid links and uncondomized affiliate links, overdone reciprocal linkage and interlinking.
All sorts of link schemes designed to increase a site's ranking or PageRank. Link scheme means for example mass exchange of links pages, repeated chunks of links per site, fishy footer links, triangular PageRank boosting, 27-way-linkage where in the end only the initiator earns a few inbounds because the participants are confused, and "genial" stuff like that. Google's pretty good at identifying link farming, and bans or penalizes accordingly. That's old news, but such techniques are still used, widely.
Advice: don't participate, Google will catch you eventually.
Paid links, if detected or reported, get devalued. That is, they don't help the link destination's search engine rankings, and in some cases the source will lose its ability to pass reputation via links. Google does this more or less silently since 2003 at least, probably longer, but until today there was no precise definition of risky paid links.
That's going to change. Adam Lasnik, commenting Eric Enge's "It seems to me that one of the more challenging aspects of all of this is that people have gotten really good at buying a link that show no indication that they are purchased."
Yes and no, actually. One of the things I think Matt has commented about in his blog; it's what we joking refer to as famous last words, which is "well, I have come up with a way to buy links that is completely undetectable".So it seems Google's just after PageRank selling. Adam's following comments on the use and abuse of rel-nofollow emphasizes this interpretation:
As people have pointed out, Google buys advertising, and a lot of other great sites engage in both the buying and selling of advertising. There is no problem with that whatsoever. The problem is that we've seen quite a bit of buying and selling for the very clear purpose of transferring PageRank. Some times we see people out there saying "hey, I've got a PR8 site" and, "this will give you some great Google boost, and I am selling it for just three hundred a month". Well, that's blunt, and that's clearly in violation of the "do not engage in linking schemes that are not permitted within the webmaster guidelines".
Two, taking a step back, our goal is not to catch one hundred percent of paid links [emphasis mine]. It's to try to address the egregious behavior of buying and selling the links that focus on the passing of PageRank. That type of behavior is a lot more readily identifiable then I think people give us credit for.
Matt Cutts has updated (May 12th, 2007) an older and well linked post on paid links. It also covers thoughts on the value of directory links. Here are a few quotes, but don't miss out on Matt's post:
... we’re open to semi-automatic approaches to ignore paid links, which could include the best of algorithmic and manual approaches.To get a better idea on how Google's search quality team chases paid links, read Brian White's post Paid Link Schemes Inside Original Content.
Q: Now when you say "paid links", what exactly do you mean by that? Do you view all paid links as potential violations of Google’s quality guidelines?
A: Good question. As someone working on quality and relevance at Google, my bottom-line concern is clean and relevant search results on Google. As such, I care about paid links that flow PageRank and attempt to game Google's rankings. I'm not worried about links that are paid but don't affect search engines. So when I say "paid links" it's pretty safe to add in your head "paid links that flow PageRank and attempt to game Google’s rankings."
Q: This is all well and fine, but I decide what to do on my site. I can do anything I want on it, including selling links.
A: You’re 100% right; you can do absolutely anything you want on your site. But in the same way, I believe Google has the right to do whatever we think is best (in our index, algorithms, or scoring) to return relevant results.
Q: Hey, as long as we’re talking about directories, can you talk about the role of directories, some of whom charge for a reviewer to evaluate them?
A: I'll try to give a few rules of thumb to think about when looking at a directory. When considering submitting to a directory, I'd ask questions like:
- Does the directory reject URLs? If every URL passes a review, the directory gets closer to just a list of links or a free-for-all link site.
- What is the quality of urls in the directory? Suppose a site rejects 25% of submissions, but the urls that are accepted/listed are still quite low-quality or spammy. That doesn’t speak well to the quality of the directory.
- If there is a fee, what’s the purpose of the fee? For a high-quality directory, the fee is primarily for the time/effort for someone to do a genuine evaluation of a url or site.
Those are a few factors I'd consider. If you put on your user hat and ask "Does this seem like a high-quality directory to me?" you can usually get a pretty good sense as well, or ask a few friends for their take on a particular directory.
Advice: either nofollow paid links, or don't get caught. If you buy links, pay only for the traffic, because with or without link condom there's no search engine love involved.
Affiliate links are seen as kinda subset of paid links. Google can identify most (unmasked) affiliate links. Frankly, there's no advantage in passing link love to sponsors.
Reciprocal links without much doubt nullify each other. Overdone reciprocal linkage may even cause penalties, that is the reciprocal links area of a site gets qualified as link farm, for possible consequences scroll up a bit. Reciprocal links are natural links, and Google honors them if the link profile of a site or network does not consist of a unnnatural high number of reciprocal or triangular link exchanges. It may be that natural reciprocal links pass (at least a portion of) PageRank, but no (or less than one-way links) revelancy via anchor text and trust or other link reputation.
Matt Cutts discussing "Google Hell":
Reciprocal links by themselves aren't automatically bad, but we've communicated before that there is such a thing as excessive reciprocal linking. [...] As Google changes algorithms over time, excessive reciprocal links will probably carry less weight. That could also account for a site having more pages in supplemental results if excessive reciprocal links (or other link-building techniques) begin to be counted less. As I said in January: "The approach I'd recommend in that case is to use solid white-hat SEO to get high-quality links (e.g. editorially given by other sites on the basis of merit)."
Advice: It's safe to consider reciprocal links somewhat helpful, but don't actively chase for reciprocal links.
Interlinking all sites in a network can be counterproductive, but selfish cross-linking is not penalized in general. There's no "interlinking penalty" when these links make sound business sense, even when the interlinked sites aren't topically related. Interlinking sites handling each and every yellow page category on the other hand may be considered overdone. In some industries like adult entertainment, where it's hard to gain natural links, many webmasters try to boost their rankings with links from other (unrelated) sites they own or control. Operating hundreds or thousands of interlinked travel sites spread on many domains and subdomains is risky too. In the best case such linking patterns may be just ignored by Google, that is they've no or very low impact on rankings at all, but it's easy to convert a honest network into a link farm by mistake.
Advice: Carefully interlink your own sites in smaller networks, but partition these links by theme or branch in huge clusters. Consider consolidating closely related sites.
So what does all that mean for Webmasters?
Some might argue "if it ain't broke don't fix it", in other words "why should I revamp my linkage when I rank fine?". Well, rules like "any attempt to improve on a system that already works is pointless and may even be detrimental" are pointless and detrimental in a context where everything changes daily. Especially, when the tiny link-systems designed to fool another system, passively interact with that huge system (the search engine polls linkage data for all kinds of analyses). In that case the large system can change the laws of the game at any time to outsmart all the tiny cheats. So just because Google didn't discover all link schemes or shabby reciprocal link cycles out there, that does not mean the participants are safe forever. Nothing's set in stone, not even rankings, so better revise your ancient sins.
Bear in mind that Google maintains a database containing all links in the known universe back to 1998 or so, and that a current penalty may be the result of a historical analysis of a site's link attitude. So when a site is squeaky clean today but doesn't rank adequately, consider a reinclusion request if you've cheated in the past.
Before you think of penalties as the cause of downranked or even vanished pages, analyze your inbound links that might have started counting for less. Pull all your inbound links from Site Explorer or Webmaster Central, then remove questionable sources from the list:
- Paid links and affiliate links where you 301-redirect all landing pages with affiliate IDs in the query string to a canonical landing page,
- Links from fishy directories, links lists, FFAs, top rank lists, DMOZ-clones and stuff like that,
- Links from URLs which may be considered search results,
- Links from sites you control or which live off your contents,
- Links from sites engaged in reciprocal link swaps with your sites,
- Links from sites which link out to too many questionable pages in link directories or where users can insert links without editorial control,
- Links from shabby sites regardless their toolbar PageRank,
- Links from links pages which don't provide editorial contents,
- Links from blog comments, forum signatures, guestbooks and other places where you can easily drop URLs,
- Nofollow'ed links and links routed via uncrawlable redirect scripts,
Look at the shrinked list of inbound links and ask yourself where on the SERPs a search engine should rank your stuff based on these remaining votes. Frustrated? Learn the fine art of link building from an expert in the field.
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