President Trump has signed a law increasing fines on spammy robocalls. The law requires phone service providers to begin authenticating calls across networks.

The telephone robocall abuse criminal enforcement and deterrence act was signed on Monday. Congress approved the landmark bill earlier this month to give the federal government new abilities to go after illegal robocallers. Fines can now reach $ 10,000 per call.

Federal Communications Commission chairman Ajit Pai said he’s glad the agency’has a longer statute of limitations’ to pursue scammers.

Carriers have already begun to deploy the stir/shaken technology in anticipation of the new law. Eventually, companies like at & T and Verizon should be able to verify calls between their networks.