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Four companies that made billions of illegal robocalls have been caught and fined.

The Federal Trade Commission on Tuesday said the agency reached settlements with four operations responsible for billions of illegal robocalls pitching debt-relief services, home security systems, fake charities, auto warranties and Google search results services. The companies were charged with violating the FTC Act, as well as the agency's Telemarketing Sales Rule and its Do Not Call provisions.

"We have brought dozens of cases targeting illegal robocalls, and fighting unwanted calls remains one of our highest priorities," said Andrew Smith, director of the Bureau of Consumer Protection at the FTC, in a release. "We also have great advice on call-blocking services and how to reduce unwanted calls at [our website.]"

The settlements come as the agency focuses on combating illegal robocalls. The four companies, NetDotSolutions, Higher Goals Marketing, Veterans of America and Pointbreak Media, are banned by court orders from robocalling and most telemarketing activities, according to the FTC's release.

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Industry analysts in September predicted that nearly half of the mobile phone calls we get this year would be scams. The Federal Communications Commission has been calling on carriers to step up their game in combating robocalls. FCC Chairman Ajit Pai last month said phone companies need to implement robust caller ID authentication systems by the end of this year. If they don't, the FCC will consider "regulatory intervention."

The fines the FTC imposed on the companies and their owners range from $500,000 to over $3 million. Some of the proposed settlements are still waiting for final court approval.