Pay Per Click search engines revolutionised marketing. Sellers can now reach buyers with speed and precision that wasn’t imaginable a few years ago.

Pay per click engines are similar to familiar search engines used for usual researches but beyond our knowledge, this activity is actually generating income for companies hosting pay per click search engines. The business goes when advertisers publish the ads of their products on the web pages of search results. Promoters are charged by the host engine whenever a searcher or surfer on the net clicks on the search listing on the web, in particular to their product ads. These pages are usually listed in bidding amounts, so the more the searchers choosing and clicking the advertisement ads of the company, the higher the profit that these search engine hosts enjoys.

Among the popular pay per click search engines are the Google Adwords, Yahoo Search Marketing (Overture) and EPilot. Amidst this blooming advertising business, an alarming problem of fraudulent pay per click operation is threatening. This pay per click fraud or simply called “click fraud” occurs when perpetrators cheat to generate several clicks on ads, and then collect commission from pay-per-click programs. Click fraud is a scheme that takes advantage of online advertising programs like those offered by Google, Yahoo, Findwhat and others.

Click fraud hurts advertisers by increasing the cost of each click since many online advertising programs adjust the price of each click based on the attractiveness of a particular keyword and the number of competing advertisers. Popular keywords can take just a few minutes to register hundreds of clicks, generating income for the “fraudsters”. Click fraud can quickly eat up your pay-per-click account and leave you a little for your expenditure.

Click fraud occurs when the people behind Web sites that display PPC ads, who also receive a portion of the revenue, start self-clicking the ads repeatedly, either using automated clicking programs called “hitbots” or employ low-wage employees to click the links. To evade attempts by the major advertising channels to detect clicks coming from a single Internet Protocol (IP) address, such software uses techniques that generate fake but believable IP addresses of many anonymous proxy servers on the Web. These servers can have legitimate uses, such as making one's Web surfing anonymous. But many proxies allow almost all identification of a visitor, including the country, to be faked.

A federal grand jury returned an indictment against a 32-year-old citizen of Oak Park California. He was charged with fraud and extortion for a scheme involving Google's pay-per-click program. He actually tried to extort Google Adwords into paying $100,000 for click fraud software he created called "Google Clique." Some experts believe fraudulent pay-per-click schemes represent about 10% of billings in the rapidly mounting field of paid search-engine marketing. Despite these cases, major search engine companies are reluctant to speak about the schemes and counter-measures that the sites are taking against them.

Now, if you have been unfortunate to be a victim, there are ways to find the culprit. When checking your log files notice if there is a lot of clicks from one IP address trace its origin by the help of American Registry of Internet Numbers. You will then know who has been assigned that IP address, and whether it's an actual IP or another business entity. If it’s not within America, there’s RIPE Network Coordination Center for all Russian, European, and Middle Eastern registries, or the Asia Pacific Network Information Center. These three sites would make you able to track the source. On the other hand, regularly auditing your website's log files and immediately reporting suspicious traffic to the pay-per-click companies may also reduce your risk of being victimized. Excellent software products like ClickTracks, WebTrends, and AWStats may also help you avoid click fraud.