It's interesting that Google puts so much effort into this, and yet continues to let the flood of ads for fake and counterfeit goods continue.
For one class of often-faked product, they are showing ads relating to more than 10 000 domains selling Chinese-made counterfeits.
These are high-end products and the fake sites are trying to pass off fake goods as if they are the real thing. With Google accepting these ads and displaying them widely, the counterfeiters are cashing in. The fake sites almost always infringe trademark law, and are using the names of real companies as a part of the domain name.
Some estimates put the counterfeiters' earnings at 5 to 10 million dollars per week. Others at almost that amount per day.
It is totally obvious this stuff is fake, and yet Google seemingly takes no action on this at all. This scam has been running for years; yet Google is happy to take vast amounts of money from the criminals.