I have discovered a competitor clicking on a client ad. I was able to use the geographic report to see that the clicks were coming from the same location, which happened to coincide with a competitor location and also happened to be in the middle of nowhere. He was also the only competitor that showed any movement in the auction insights. I excluded a small radius around his location and the clicks stopped. I removed the exclusion and they started again. I documented it all and took it to Google, laying it out like a court case. They said they would "investigate", so I knew nothing would happen. In 2 days, not only was the competitor no longer showing ads, it looked as if he had been totally blacklisted. no GMB, no ads, nothing.