A US resident is suing broadband provider Comcast claiming that the firm limits the bandwidth of customers who use peer-to-peer software.
The lawsuit, filed by Jon Hart, claims that Comcast has breached its contract and breached the covenant of good faith and fair dealing.
Comcast is also accused of breaking Business and Professions Code 17200 and falling foul of the Consumer Legal Remedies Act.
Hart has asked for a jury trial and names all other similarly affected customers in the hope of starting a class action suit.
The legal filing states that broadband companies market their services as operating at "lightening fast" and "mind blowing" speeds with "unfettered access to all the internet has to offer".
"Nevertheless, defendants intentionally and severely impede the use of certain internet applications by their customers, slowing such applications to a mere crawl or stopping them altogether," the legal document states.
Hart also claimed that the practice of sending unauthorised messages to a PC to stop those applications violates the Computer Fraud and Abuse Act.
He claims that the 22-page terms and conditions he had to agree to when signing up for Comcast's Performance Plus package do not mention that certain applications will be blocked.
Hart described the company's actions as "immoral, unethical, oppressive, unscrupulous and/or substantially injurious to consumers".
Comcast was found to be blocking BitTorrent traffic in October.
