Google is banning a Chinese developer from the Play store for violating its advertising policies. CooTek, which is listed on the NYSE and is probably best known in the West for its TouchPal keyboard replacement, no longer has access to Google’s ad platforms and has had dozens of apps removed altogether.

The news was reported by BuzzFeed following an investigation from Lookout that showed hundreds of CooTek apps using an invasive adware plugin called BeiTaAd. This plugin reportedly sent aggressive ads to users even when the phone or the app wasn’t in use, which Lookout researcher Kristina Balaam said could “render the phones nearly unusable.”

CooTek said it would remove BeiTaAd, but BuzzFeed and Lookout subsequently discovered that many of the updated apps — which Google accepted into the Play Store — contained separate code that enabled the same ads.

“There was not any re-engagement on the ad activity pointed out by Lookout on any of the versions which we updated,” CooTek spokesperson Mina Luo told BuzzFeed. “The findings claimed by Lookout this time are lack of evidence [sic] and the logic is not convincing.”

Google, however, was convinced. “Our Google Play developer policies strictly prohibit malicious and deceptive behavior, as well as disruptive ads,” a Google spokesperson said to BuzzFeed. “When violations are found, we take action.”

This isn’t the first time Google has had to take action against Chinese developers for abusing Play store app policies. Do Global was banned in April for similar violations, while the company also took action against Cheetah Mobile and Kika Tech last year.