Marriott will have to fork over $600,000 in fines to the Federal Communications Commission (FCC) after an investigation revealed that hotel employees used a Wi-Fi monitoring system to intentionally prevent customers from  connecting to the Internet through their personal Wi-Fi networks, while at the same time charging them up to $1,000 per device to access Marriott’s own Wi-Fi network.

As part of the settlement, Marriott agreed to immediately cease unlawful use of Wi-Fi blocking technology and to “take significant steps” to improve how it monitors and uses such technology. On top of that, the hotel chain will institute a compliance plan for any U.S. property it manages or owns, and file reports with the FCC every three months for the next three years.

“Consumers who purchase cellular data plans should be able to use them without fear that their personal Internet connection will be blocked by their hotel or conference center,” said FCC Enforcement Bureau Chief Travis LeBlanc in a news release. “It is unacceptable for any hotel to intentionally disable personal hotspots while also charging consumers and small businesses high fees to use the hotel’s own Wi-Fi network.”

The FCC became aware of Marriott’s shady Wi-Fi practices when it received a complaint in March 2013 from someone who had attended a function at the Gaylord Opryland, alleging that the hotel was “jamming mobile hotspots so  that you can’t use them in the convention space.”

Marriott, for its part, continues to claim that it has done nothing illegal.

“Marriott has a strong interest in ensuring that when our guests use our Wi-Fi service, they will be protected from rogue wireless hotspots that can cause degraded service, insidious cyber-attacks and identity theft,” Jeff Flaherty, a company spokesman, said in an e-mailed statement to Bloomberg.