google_ad_client = "pub-1234567890123456";

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Google
We understand that you may have questions about what Google is doing to prevent invalid click activity. You should know that our specialists carefully monitor clicks and impressions on Google ads in order to protect the interests of our advertisers, our AdSense publishers, and our users. To do this, we use both automated systems and human reviews, analyzing all ad clicks and impressions for any invalid click activity that may artificially drive up an advertiser's costs or a publisher's earnings.
Google's proprietary technology analyzes clicks and impressions to determine whether they fit a pattern of use that may artificially drive up an advertiser's costs or a publisher's earnings. Our system uses sophisticated filters to distinguish between activity generated through normal use by users and activity that may pose a risk to our AdWords advertisers. Some examples of this activity include clicks or impressions generated by unethical users, automated robots and traffic sources, publishers encouraging clicks on their ads, and scenarios where a malicious third party attempts to forge invalid clicks or impressions with a publishers identifier with the intent of harming this publisher. Our system enables us to filter out most invalid clicks and impressions, and our advertisers are not charged for this activity.

In addition to our automated system, we have a team dedicated to detecting invalid activity using several specialized tools and a wide variety of techniques based on extensive experience tracking and monitoring user behavior and analyzing scenarios. We continually upgrade our detection mechanisms to proactively combat invalid activity.
For more information about invalid click activity, we recommend visiting [www.google.com] .

Furthermore, AdSense offers a feature called "Allowed Sites", which allows publishers who are concerned about misuse of their ad code (publisher id) to specify which sites their AdSense id may legitimately appear on. For more information on this feature, see [adsense.blogspot.com] .



You also may find additional information on Google's Ad Traffic Quality efforts at [www.google.com] .

In particular, a forthcoming book chapter on "Online Advertising Fraud" specifically addresses concerns regarding sabotage of an advertiser (see bottom of page 19 in the section on "Detection" in the book chapter at [www.google.com]):

"After filters have been applied and invalid clicks have been identified, additional actions may be
required. For instance, an AdSense publisher with a high percentage of invalid
clicks, or even just one that received potentially anomalous traffic that may or
may not be invalid may be inspected by an ad traffic quality investigator.
In certain cases, a relationship with a publisher may be automatically terminated
if unusual proportions of invalid clicks are attracted by the publisher's web site.
As such, ad traffic quality investigators need to also be mindful of potential
sabotage that may occur in which a malicious publisher attempts to generate
a large number of invalid clicks on a competing publisher's web site to make it
seem as if the competitor is attempting a click inflation attack."


I hope the above information demonstrates to you that the concern you brought up is well understood by Google and is taken into account in our AdSense fraud and abuse countermeasures.

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After filters have been applied