Bid based and flat rate is the two most common pay-per-click (PPC) ad services on the Internet. Google AdWords, Yahoo! Search Marketing and Microsoft adCenter are the three largest network operators that are based on bid-based pay-per-click advertising. Yahoo! and Microsoft combined their efforts in 2010 under Microsoft adCenter in order to better compete with Google AdWords. Advertisers sign a contract allowing them to compete with other advertisers for the ad spot. The automated auction system determines ad spot each time a customer triggers a search. The other method, Flat-rate PPC model, charges and pays an agreed fixed rate fee for each click. Rate varies based on content on pages and negotiations. Even though rates are fixed, advertisers may have to pay more for greater visibility.
The Australian Competition and Consumer Commission declared in 2012 that Google has engaged in misleading and deceptive conduct by its sponsored AdWords advertising. The case is connected to a advertisement for car sales where the Web site bears the same name and connected to a particular brand of cars. However, on appeal the Australian High Court overturn the ruling and found Google not liable for the misleading advertisement. The area based geo-targeted advertising continues to help small and local businesses.