A federal appeals court on Thursday upheld decades-old media ownership rules that prevent a single owner from controlling a newspaper and broadcast station in the same city.

The 3rd U.S. Circuit Court of Appeals in Philadelphia ruled that the Federal Communications Commission didn’t give the public enough notice to weigh in on its 2007 decision to relax cross-ownership rules under former chairman Kevin Martin. The court sent the rules back to the FCC to be rewritten.

The original ownership rules date to the mid 1970s, when the FCC decided that a single owner should not have broadcast and print media holdings in the same local market. The idea was that having multiple owners of media outlets provided a diversity of voices.

Since then, the media industry has undergone massive change. Newspapers and television stations compete with smartphone apps and news aggregators such as Google and the Drudge Report. Power is being concentrated in other ways: Comcast serves the highest number of high-speed cable Internet users and owns some of the nation’s most coveted media franchises through NBC Universal.

Public interest groups, which challenged the FCC’s action, argue that even as options for accessing information continue to multiply, allowing a small concentration of companies to create that content — news reports, videos and columns — limits the number of voices and opinions in the public discourse.

“In rejecting the arguments of the industry and exposing the FCC’s failures, the court wisely concluded that competition in the media – not more concentration – will provide Americans with the local news and information they need and want,” said Corey Wright, a policy counsel at public interest group Free Press.

The FCC lamented in a report last month that local news coverage has declined as the news industry struggles with revenue losses and massive staff cuts. The cutbacks have hurt investigative and accountability reporting, the agency said.

FCC General Counsel Austin Schlick said in a statement that the court’s decision “affirms the FCC’s authority to promote competition, localism, and diversity in the modern media marketplace.” He said the agency is updating its ownership rules, as required every four years by Congress.

But media titans, including News Corp., CBS and Gannett, have fought to upend the old rules, saying the landscape has changed too much to keep pre-Internet regulations.

Nearly half of all American adults said they get some kind of local news or information from smartphones and tablets, according to a March 2011 report by the Pew Internet & American Life Project. That could include weather reports, school information or other news.