CNET/Marguerite Reardon

The US Supreme Court has declined to hear an appeal related to Obama-era net neutrality regulations that could have gutted the authority of the Federal Communications Commission.

On Monday, the high court rejected an appeal that challenged a 2016 decision by the DC Circuit Court of Appeals, which upheld the rules to protect an open internet and validated the FCC's authority to pass such rules.

The 2015 rules were rolled back by the Republican-led FCC late last year, and they were officially taken off the books in June. However, the appeal sought to wipe the DC Circuit's ruling from the books so the parts of its decision that upheld the FCC's authority couldn't be used as precedent in any subsequent cases.

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Groups supporting net neutrality and companies like Mozilla, which back the 2015 rules, are suing the FCC over its repeal of the rules last December.

But now the battle over whether the FCC had the right to pass those rules in the first place is dead. By refusing to hear the appeal, the Supreme Court has left in place the DC Circuit's 2016 decision.

Is this a big deal? It depends on who you ask. Given that the Republican-led FCC repealed the controversial rules last December, the point is moot. The rules no longer exist anyway.

And some legal experts say that even if the Supreme Court had thrown out the lower court's 2016 decision, it would have amounted to a bit of legal housecleaning with no serious affect on future cases.

But net neutrality supporters disagree. They say that tossing out the legal precedent might have affected the next legal battle over the FCC's repeal of net neutrality. Net neutrality supporters are hoping that the lower court's ruling to uphold the FCC's decision to reclassify broadband as a utility will help with their case challenging the FCC's repeal of the rules.

Net neutrality is the idea that all traffic on the internet should be treated equally and that broadband providers should not act as gatekeepers of content or services on the internet. The rules adopted by the FCC in 2015 banned ISPs from blocking or slowing down access to content online and prevented them from giving preferential treatment to their own services. The rules also reclassified broadband as a public utility, subjecting ISPs to stricter regulations.

Net neutrality supporters have said the rules would keep broadband providers in check. But the opponents have said the reclassification of broadband would stifle investment and innovation.

According to the court, Justices Samuel Alito, Neil Gorsuch and Clarence Thomas would have granted the industry's request to set aside the decision. Chief Justice John Roberts and Justice Brett Kavanaugh recused themselves from the decision of whether to take the case.

Kavanaugh wrote a dissenting opinion for the 2016 case when he was on the DC Circuit Court of Appeals. Roberts has an investment portfolio that includes telecommunications companies, according to the Associated Press.

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