When it comes to Google, you'd better not try any mischief.
The Internet giant has very specific guidelines for Web sites that want to be found with its search engine. But when those sites don't comply, it isn't long before they get a slap on the wrist or worse.
"If a site has been penalized, it may no longer show up in results on Google.com or on any of Google's partner sites," Google says on a page devoted to Webmaster guidelines.
And don't think they aren't serious. Web sites belonging to corporations, individuals and political campaigns have been buried or banned altogether because of tactics that game or disrupt Google's system.
Hutchison's Campaign Site Gets the Boot
In the latest search engine showdown, Google blocked the Web site of Texas Sen. Kay Bailey Hutchison's gubernatorial campaign last week after it found hidden text in the Web site's source code.
To the average visitor, www.standbykay.com looked like any other political site. But those who could pull back the layers of the Web found something else.
According to the Austin American-Statesman, the source code for the site included more than 2,200 hidden phrases, including word combinations with Hutchison's name and Rick Perry, the name of the incumbent. The newspaper said it also included the phrase "rick perry gay."
A spokesman for Hutchison's campaign told ABCNews.com that its Web technology company, ElectionMall Technologies was informed by Google last week that the site had violated its guidelines. He also said that they had dismissed the firm.
When contacted by ABCNews.com, ElectionMall declined to give a comment.
The URL standbykay.com has been discontinued and directs to texansforkay.com. But when it was still alive, aides for the senator said the phrases were computer-generated based on campaign-related terms that Internet users would likely search for and were intended to help target online banner advertising, the Statesman reported.
But hiding text in source code is a giant Google no-no.
Violating Google Guidelines Results in Removal
"Google did take action on this site for hidden text. Hidden text is a violation of our quality guidelines," a company spokesman said in a statement, adding that it had removed the site from its index.
But Hutchison's campaign site isn't the only one to have found itself on the wrong side of Google. Here are five other sites that have been banned or buried.
BMW Germany Blocked for Deceptive Practices
In February 2006, Google gave BMW Germany the Internet kiss of death when it discovered that the car company was presenting different content to visitors to its site than it was to the search engines.
"That's a violation of our webmaster quality guidelines, specifically the principle of 'Don't deceive your users or present different content to search engines than you display to users,'" Matt Cutts, the head of Google's Web spam team, wrote on his blog at the time.
Although the Web site might give ordinary visitors a page chock-full of brand new Beemers, search engines would see a page of search-friendly text.
Google reduced BMW's page rank to zero, which meant that when Internet users searched "BMW," it would no longer appear at the top of the page.
According to the BBC, a BMW spokesman acknowledged at the time that the company used so-called doorway pages, which are large sets of search-engine optimized pages intended to boost a site's search rank.
But the spokesman denied misleading users.
"We did not provide different content in the search results to the final Web site," Markus Sagemann told the BBC News. "However, if Google says all doorway pages are illegal we have to take this into consideration."
In a matter of days, however, Google restored the Web site to its index.
Traffic-Power Banished From Google
Google doesn't usually comment on specific sites that flout their guidelines (even Cutts' blog posts usually don't single out trouble sites) but in January 2006 they broke with tradition.
In a post, Cutts confirmed that Google had banned Traffic-Power.com and sites affiliated with it from their index.
Traffic-Power.com appears to no longer exist, but it had been a search engine placement firm that helps other Web sites boost their ranking. Google said its tactics rigged the system to help its clients and removed it permanently.
GoCompare's Traffic Tumbles After Google Rap
So, what exactly happens if a site is just punished, but not totally removed, by Google?
In February 2008, Hitwise, a firm that measures Web site traffic, took a look at GoCompare, a U.K. insurance comparison Web site, to figure that out.
After Google found irregular inbound links to the site, which help improve the ranking but are not necessarily relevant to the rest of the content on the page, it reduced the company's ranking.
In the week ending Jan. 26, 2008, GoCompare was the number one site receiving traffic from the search term "car insurance" and capturing 17.49 percent of the all search traffic from the term, according to HitWise.
But by the week ending Feb. 9, 2008 -- after the site was "blacklisted" by Google -- it dropped out of the top 10 and captured only 2.31 percent of the traffic from "car insurance."
Google Vs. Google
But though it may rule the Web, Google isn't beyond reproach.
In 2006, it punished itself.
Text intended to be internal was showing up on public pages. But, to be consistent, the company removed the pages from its own index.
"When it was noticed, people in the space who sometimes fight with Google said 'why don't you ban yourself?' And then they did," said Danny Sullivan, editor in chief of the industry Web site Search Engine Land. "That was indeed quite a chuckle."
In December 2008, it penalized itself again -- temporarily, at least.
Because of a glitch, searches for "google," "analytics," "google adwords," and other terms didn't return the normal Google.com result.
But soon after noticing the mistake, Google issued a statement saying, "Unfortunately, for a short period of time yesterday, we experienced an issue where our search engine wasn't returning some pages hosted on google.com in users' search results.
"We've since fixed this problem, and users can now find all Google-specific sites they are searching for. We apologize for any inconvenience this may have caused," the statement continued.
In February of this year, however, it faced a different situation.
The Web spam team learned that Google Japan was paying for blogger reviews, which violates the company's search guidelines.
Google's Cutts tweeted, "Google.co.jp PageRank is now ~5 instead of ~9. I expect that to remain for a while."
Barry Schwartz, owner of Web consulting firm RustyBrick and executive editor of Search Engine RoundTable, said the penalty lasted for a few weeks.
"Google typically doesn't go after individual Web sites," he said, adding that filters usually search the Web for spam. When the spam team finds sites that are breaking the rules, they contact them and go through a reconsideration process to bring the site in line.
Google Vs. the Entire Internet
Earlier this year, the search engine community -- and Internet users around the world -- had another chuckle.
In January, Google flagged the entire Internet as Malware for one Saturday morning.
Usually the warnings are meant to alert users to sites that could harm their computers, but the error meant that every person who used Google to search saw a warning next to every site listed.
Search Engine Land's Sullivan estimated that the short-lived problem probably meant that the company took some kind of revenue hit. At the very least, it gave the larger-than-life tech firm a moment of humility.