The US Supreme Court has ruled that cable firms do not have to share their networks with other broadband providers.
Cable firms get to keep their networks to themselves
It follows an attempt by California-based broadband firm Brand X to get access to cable lines.
The Supreme Court voted six to three to uphold an original ruling that exempted cable firms from sharing their lines.
Consumer groups warned it could stifle competition and lead to price hikes for customers
The original decision to allow cable firms to keep their networks to themselves was passed by the US Federal Communications Commission (FCC) as a way of encouraging them to build up their broadband offerings.
As in the UK, phone firms have to rent their lines to other operators.
But the FCC said different rules should apply to cable firms because they were providing an information service rather than a phone service.
The 2002 decision was overturned a year later by the US Court of Appeals which said that internet providers should be granted access to the cable networks.
Cable firms applauded Monday's Supreme Court decision.
"It removes the regulatory uncertainty and for all of us who want to offer high-speed internet access, it gives us every incentive now to continue investing and continue innovating," said Kyle McSlarrow, president of the National Cable and Telecommunications Association.
However, consumer groups were unhappy with the verdict.
The ruling "threatens to cement the cosy duopoly of cable modem and DSL service that has made a mockery of competition in American broadband markets and prompted hundreds of communities across the country to build their own local networks," read a joint statement from the Consumer Federation of America, the Consumers Union and the Free Press.
Brand X originally brought the case to court when it discovered that the plug could be pulled on discounted rates it got for using lines from a variety of phone companies.
"This is just terrible and the real losers in this decision are consumers, because consumers benefit from choice and competition," said Brand X president Jim Pickrell.
He said his company may have to shut down.
Unlike in the UK, cable is leading the way in terms of broadband subscriptions in the US with an estimated six out of 10 homes using cable in favour of phone-based DSL (Digital Subscriber Line) service.
Around 53% of homes have a broadband connection in the US.