On SEO forums one of the most often discussed topics are Google penalties. Webmasters seek help to determine whether and why they have been penalised by Google. They also want to know how to deal with the penalty once it’s established that they have been hit by one.

What is a Google penalty and what isn’t? There seem to be different definitions floating around.

While Google employees will tell you that many SEO issues described as penalties aren’t actually penalties, most people seem to consider sudden and unexplained ranking and/or search traffic drops as a penalty. They at least suspect they have been subjected to a penalty.

Today I’d like to assist webmasters in determining whether they have been hit by an actual Google penalty by listing common reasons for getting penalised by Google.

Some of them are simply Google filters that deal with overtly manipulative SEO techniques. Some of these aren’t penalties at all, but I list them here as well because they are often mistaken for a penalty.

So just check out this list of ways to get penalised by Google. Many of them are high risk SEO tactics considered to be black hat by some.



Backlinks

Large parts of the SEO industry still focus on link building or getting links to improve search engine visibility especially on Google. There is nothing wrong with that. Of course there are limits. There are now so many pitfalls to link building that you have to be very exact when it comes to following the Google Webmaster Guidelines.

5000 links for $19 – dubious offers from spam emails offering you 5000 links for $19 are too good to be true. They lead almost directly to a penalty.
Paid links on high PR sites – while you can get away with paid links in many cases, it’s quite easy to get noticed when you buy links on so-called high PR sites where the toolbar PageRank is 6 and above. There are only a handful of sites that have PR9 and even the number of PageRank 8 sites is easy to monitor. PageRank sites like Piwik.org that have a ten are so obvious you could call Matt Cutts and tell him about it yourself.
Reciprocal links on large scale – link exchange and reciprocal links are natural to some extent. I link out to bloggers who link to me on a daily basis. On the other hand, obvious and massive link exchange schemes or networks can be detected algorithmically, so you end up penalised sooner or later.
Hidden links in WordPress themes or counters – these days many top ranking free WordPress themes sites are just SEO scams which rely on hidden links in the themes to be spread around. If you rely on such links for “link building”, it’s no wonder you are being penalised. Some visitor counters have done that in the past as well.
Artificial link profile with always matching anchor text – when every single link to your site is well optimised saying something like “SEO company” this might look too artificial to stay unnoticed by Google.
Wrong language links – an English site having thousands of links from Russia or China makes me go hmmm. Google engineers are smart enough to compare the language of your site and the sites that link to you. In the best case you just rank in Russia and China. Else you drop altogether.
Gaining too many links too fast – it’s not always the more links the better. Even good links gained too fast can result in a penalty. Google is checking the link velocity – aka the rate in which you earn links – and if you get more links than you deserve, you risk a penalty even if the links are perfectly legit.



Outgoing links

Linking out is crucial for blogs and even static websites. Many webmasters stopped likning out in order to hoard PageRank. Google engineers have discouraged this and suggested linking out instead. Linking out can be risky though.

Broken links – too many broken links on a page raise a red flag in the Google algorithm. This might not be a penalty in the strictest sense, but you drop suddenly in rankings once more than one or two links are broken on a page.
Links to bad neighborhoods – even worse than 404 errors (aka broken links) are links redirected to so called bad neighbourhoods. Spammers even use this technique on purpose to fool you. Most such links happen more naturally as part of link decay. Sites disappear and domain grabbers buy them to display ad loaded “domain parking” pages.
Too many outbound links or none at all – a site that has more outgoing links than content itself can lose its search visibility. This might not happen overnight like the typical penalty you’d expect, but it can amount to one in its effects. Also, sites that are dead-ends (that do not link out at all, or use use nofollow links out of the misguided belief that it’s good SEO) might get penalised completely.
Hidden links in third party services (menus, widgets, counters) – free services for websites often have a rather sneaky business model. They sneak in a hidden link with their offering. It can be a CSS menu, a sidebar widget or a visitor counter. Sometimes these links are not only hidden; they are also off-topic and downright spammy. Look out and check the source code of stuff you add to your sites. Google, of course, doesn’t allow hidden links.



Content

Though Google always stresses that “content is king”, it also can mean trouble. If there is no king in your kingdom, or the king is dressed in rags, you look bad when the Google robots visit.

Duplicate content – duplicate content on your own site or even elsewhere can result in a significant ranking drop. While Google does not consider this a penalty, most webmasters who experience the problem do.
Low quality content – Google’s high quality update dubbed Panda focused on low quality content. Shallow, keyword-rich content on some pages can make your whole site drop in Google.
Scraped content – scraped content, that is text taken from other sites and displayed on yours, is a surefire way to get downranked.
Unreadable content – content that is written in broken English can be seen as scraped and then “spun” (some words get replaced with synonyms to fool Google), so make sure a human being understands what you write. Also, text decoration is crucial. Human quality raters employed by Google check that as well.



Ads

Analysts argue that Google is not a search engine but an advertising company as almost all revenue of the Google corporation stem from ads displayed in the search results themselves and on third party sites. Nonetheless, the pressure on Google has grown over the years to tackle the problem of so called MFA (Made for Adsense) sites that pollute the Google index. With Google “Panda” the search giant finally did.

Too many ads (low content to ads ratio) – ever since Google “Panda” has been the talk of the town, most pundits have pointed out that a too high number of ads, especially Google Adsense ads, may lead to a penalty. I agree with that opinion.
Affiliate sites with no value – Google always explained that affiliates are OK, but only as long as they offer some additional value beyond the actual affiliate offer. Be sure to add value or you will face a penalty sooner or later.



Bad press and reputation

The issue of so-called “SEO outing” has been a hot one in 2011, as numerous high profile websites have been outed and with them also their SEO teams or companies. Many SEO practitioners argue on moral grounds that outing is a despicable practice. They might be right, but as long as there is nothing to out you fare best. So you’d better manage your reputation online and from time to time check what the SEO team does.

NYT and WSJ – high profile old media outlets like the NYT (New York Times) and the WSJ (Wall Street Journal) like to scandalise SEO, so if you get a call from a journalist you’d better not brag about your shady SEO tactics. Google, in most cases, reacts to high profile outings aka bad press.
Industry blogs like SEO Book – some SEO industry blogs might focus their attention on your shady SEO business model when you get too flamboyant or obnoxious. Aaron Wall of SEO Book got so offended by the “SEO is bullshit” tirades of Mahalo owner Calacanis that he attacked his site for sites. Finally Google had to act, and penalised the thin-content site along with other offenders in the Google “Panda” update. Be sure not to slander the SEO industry if your online property is not 200% clean.
Asking questions in official Google Groups – some disgruntled webmasters tend to speak out on Google groups or forums when they feel they have been singled out and penalised. Some of these webmasters have been penalised for a good reason. These people will be outed by Google employees in the worst case scenario when they don’t admit their mistakes and keep on complaining.
Third party trust metrics like Blekko, WOT, McAfee Siteadvisor - if you don’t show up in Blekko, aka you are banned there, and when sites like WOT and SiteAdvisor list your site as deceptive or dangerous, this might mean you are heading towards a Google penalty. Google does not use these sites’ data but has other means to screen the Web for the same issues.
Making Google look stupid – you don’t need an NYT article, a SEO blogger or Google employee to get penalised for a bad rep. Publicly showing off your black hat SEO successes makes you vulnerable to the “making Google look stupid” penalty. Leading SEO specialists agree that from a certain point on, Google can’t keep quiet about it and will penalise you in order to keep its face.



Google filters

Some Google penalties are just filters that are applied automatically. While many penalties can be both manual and automatic, some of the filters are obviously algorithmic.

New domain (sandbox) – the so-called sandbox filter has been around for years, but was never officially acknowledged as far as I know. It applies when you change domains or start out with a completely new domain and site. Without a proper “moved to” sign Google will apply this penalty to old established sites as well when they change domains. Use a 301 redirect for old sites and try to gain a significant number of authority links in the early days of a new domain to beat this filter.
Multiple h1 tags – a book has just one title. Likewise a web page has only one h1 title tag. Google assumes that multiple h1 tags are a trick to spam its index, and penalises sites using multiple h1 tags. Use h2, h3 and other headline tags instead.
Keyword stuffing (high “keyword density”) – one of the oldest spam techniques is so called keyword stuffing. To this day, fake SEO specialists advise webmasters to ensure a high “keyword density” on your site. That’s nonsense. Be sure to add your keywords to your website copy, but no more than a few times. It’s more important to keep the text readable than any percentage of keywords. It might rather hurt you in Google.



Technical issues

Not every sudden drop in rankings and traffic is a penalty; some are stupidity or gross negligence. You can shoot yourself in the foot by messing with some technical aspects of web development.

Robots.txt – the robots.txt is not really needed to improve SEO. It can break a lot of things though. Just recently I blocked one of my blogs from being indexed by Google. Of course I suspected a penalty at first but then checked Google Webmaster Tools to find out I made the mistake.
Nofollow – I’ve seen leading blogs barred from the Google index because they activated the WordPress privacy mode. It simply meant that all of the blog was set to noindex, nofollow which equals blocking it in the robots.txt.
Duplicate titles and descriptions – when your site uses the same or a very similar page title and description for every single page, it’s no wonder most of them won’t show up in search results. This isn’t a penalty either. It’s just logical.
Not crawlable links in JavaScript – there are still JavaScript site menus out there that can’t get crawled by Google. Always check whether your menu uses real HTML links with “ < a href=”"> ” in it. Or at least the whole URL must show up.



Neither a penalty nor your fault

In some cases a loss of rankings or search traffic has nothing to do with you or your site. Something else changed instead, and that’s why you get outranked all of a sudden.

Algorithm change – Google changes and refines its algorithm all the time. Major changes are called updates, and sometimes mean dramatic shifts in search results. Just search for “Google Panda”. The only thing you can do then is to find out what changed and why your site does not match the new ranking factors.
Competition got better – a common “problem” is also that your competition does more SEO work than you do and one day they outrank you. A ranking change from #1 to #2 on Google can mean a traffic loss of 60 to 80%.
Current events – sometimes breaking news may push your site down. Google News results get displayed on top, and for less competitive phrases news media start to rank in regular results as well. Most of these ranking changes will vanish ofter a few days.
SERP display change – Google experiments all the time with its search results’ display. Most notably, local results from Google Places take away large parts of the screen real estate. You might rank at #1 in organic results and still get displayed at the bottom of the search results page.



There are numerous reasons to see a search traffic slump one day out of the blue. It doesn’t have to be a penalty, but if you engage in some of the high risk SEO tactics mentioned above it can be one. Make sure you have at least two web analytics tools to check what happened. Google Analytics is not perfect and sometimes the ways it measures traffic get changed overnight without notification.

Just recently, traffic from Google Image Search has been quietly moved from the referrers to search engines (where it belonged in the first place).

Once both of your web statistics tools confirm the search traffic slump, you can check out this list of 33 ways to get penalised by Google to find out whether you’re a victim of one of them.