Google is a software giant, so it does have methods of trying to prevent click fraud and decrease illicit activity on your ads. Google has a media buying algorithm, for instance, that promises that it will detect and filter out invalid clicks before you even get charged for them. Although this isn’t always the case, Google acknowledges that invalid traffic is a problem and advertisers should be aware of this and devise a strategy to prevent being a victim of click fraud. Google also has a team of real people who act as real life filters - they monitor fraudulent activity in real time. Whether it’s tweaking the algorithm to drive fraudulent clicks away from your ad, or blocking them all together, Google’s team works closely with filters to ensure that you can protect your ad campaigns. Plus, the more that filters are used, the smarter they are. Google is also great at preventing click fraud before it happens. If fraudulent activity is associated with an IP address, or if the publisher has an extremely suspicious click-through rate, Google will catch the mistake so that you don’t get charged for it. Google will not hesitate to disable accounts associated with high amounts of invalid traffic. While a majority of click fraud occurs by humans, some of it is done by bots. Google will, therefore, search for data anomalies and code samples that don’t belong, and Google will also constantly research new kinds of invalid traffic that it’s existing algorithm/filter cannot detect yet.