I discovered one of the Anti-Invalid Click system of Adsense here on my blog.

If you notice, the images used on the left side of the Adsense large square ads as shown on the screenshot below, are the images of AMAZON. And into these images I applied the new feature of AMAZON, that is the LINK ENHANCER, wherein if you point your mouse on top of an image, an AMAZON enhancer will display.

Now, since the AMAZON Enhancer will be displayed on the top of the Adsense Ads, there would be a possibility a user can accidentally click on the Adsense Ads. To avoid the invalid clicks on the Adsense Ads, Adsense automatically disable (not ban but hide or unshow) the Ads under the AMAZON enhancer, as shown on the screenshot below.

With this, even the user accidentally click the space where Adsense Ads is placed, there would be no invalid clicks that would be charged.

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