Over the course of last year, Google disabled 500 million bad ads by banning over 214,000 advertisers, according to a year-in-review report that Google’s Bad Ads team released on February 3. The report reviewed 2014’s most popular schemes, including nonexistent vacation homes, fake ebola treatments, and weight loss scams.

“We work hard to keep our advertising ecosystem clean for users, advertisers, and publishers, and continue to invest substantial resources to stop bad advertising practices,” wrote Vikaram Gupta, Director of Google’s Ads Engineering in a blog post for Google AdWords. “We have a team of analysts who work around the clock to protect users, and continue to hone our detection technology to identify bad ads and stop bad actors as it’s a vital part of keeping our ads ecosystem clean.”

All told, Google banned 7,000 advertisers for promoting counterfeit goods, half as many as last year. In 2012, Google banned 82,000 for the exact same reason, which shows that counterfeiters are having an increasingly harder time circumventing Google’s advanced enforcement systems.

In order to protect users against malicious software, Google stopped any and all ads it found that pointed to sites where there was spyware, adware, or any other type of malware. It also removed 250,000 sites from its network because they were hiding forms of malware.

Because of the sheer scale involved with combating malevolent web presences, Google flags bad ads with algorithms, and then has human employees investigate them in-person. It even has a number of quirkily named tools designed exclusively for that purpose, such as the Muppets-themed Beaker and Bunsen, the index of ads and the analytics tool respectively. The key moment, however, is when they notice something is wrong.

“This is a constantly evolving fight. Bad actors continually create more sophisticated systems and scams, so we too are continually evolving our practices, technology, and methodology in fighting these bad ads,” wrote Gupta. “The security of our users is the foundation of our ecosystem, and we’ll continue to work tirelessly to keep people safe online.”