By Steve Tawa

PHILADELPHIA (CBS) – One of the biggest business cases on the U.S. Supreme Court’s fall docket is to be argued today. The issue is whether cable TV subscribers in the Philadelphia area could sue Comcast, as a group. The outcome is likely to have a far-reaching effect on class-action lawsuits.

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The high court will consider what it calls the ‘narrow issue’ of whether a trial judge could grant class-action status, without resolving whether there was enough evidence to justify awarding damages to the class as a whole.

Customers first sued Comcast in 2003, alleging it schemed to raise rates by buying out competitors or swapping territories to create a monopoly.

“Well, the expert report that the plaintiffs put forward to prove damages on a class wide basis was not yet ready for prime time, if you will. There were a lot of issues still open in the case,” said Steve Bradbury, a partner in Dechert LLP’s Washington office, who once clerked for Justice Clarence Thomas.

Eric Cramer, a shareholder in the Center City law firm Berger and Montague, is following, but not involved in the case.

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“So, what we’re looking at here is the Supreme Court ratcheting up the kinds of evidence and proof that a plaintiff needs to show, at the class stage, in order to get a class certified.”

Comcast lawyers argued different franchises within the Philadelphia area market had different pricing. They contended customers didn’t have enough in common to qualify for class-action status.

Anti-trust specialist Howard Langer is a senior partner with the Center City firm Langer, Grogan and Diver and a law professor at Penn.

“The key thing is to see the distinctions between this case and the Wal-Mart case that they decided previously.”

Last year, the Supreme Court blocked a massive sex discrimination lawsuit against Wal-Mart, ruling more than a million female workers didn’t have enough in common to pool their claims into a single class action.

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