In the latest battle of the war over net neutrality, the D.C. Circuit Court of Appeals tossed the bulk of the Federal Communications Commission’s rules.

In 2010, the FCC promulgated an order, In re Preserving the Open Internet, colloquially known as the “net neutrality” rules. Specifically, the order imposed disclosure, antidiscrimination, and antiblocking requirements on broadband providers to promote “Internet openness.” The agency was concerned that broadband providers might prevent end-user subscribers from accessing certain providers or degrade the quality of access to certain content providers.

A carrier challenged the regulations after they took effect. In striking down the antidiscrimination and antiblocking provisions, the D.C. Circuit held in a 2-to-1 decision that the FCC had not overstepped its jurisdictional bounds by issuing the order, but said the specific rules imposed by the agency exceeded the scope of its authority.

“The Commission has adequately supported and explained its conclusion that, absent rules such as those set forth in the Open Internet Order, broadband providers represent a threat to Internet openness and could act in ways that would ultimately inhibit the speed and extent of future broadband deployment,” the panel wrote.

However, the Commission violated the Communications Act by treating broadband providers as common carriers. Broadband providers were classified by the FCC in 2002 as an “information” service not subject to common carrier rules (like telephone companies, for example).

“We have little hesitation in concluding that the anti-discrimination obligation imposed on fixed broadband providers has relegated [those providers], pro tanto, to common carrier status,” the court said. “In requiring broadband providers to serve all edge providers without ‘unreasonable discrimination,’ this rule by its very terms compels those providers to hold themselves out ‘to serve the public indiscriminately.’ ”

The court noted that it was “somewhat less clear” whether the antiblocking rules established common carrier obligations, but it found that the rules established a minimum level of service that broadband providers had to furnish to all edge providers without charge. “In requiring that all edge providers receive this minimum level of access for free, these rules would appear on their face to impose per se common carrier obligations with respect to that minimum level of service,” the court wrote.

The D.C. Circuit did uphold the FCC’s disclosure rules, concluding that it did not impose common carrier obligations on broadband providers and was severable from the other rules.

To read the D.C. Circuit’s opinion, click here.

Why it matters: Net neutrality may have taken a serious blow but proponents are already regrouping. FCC Chairman Tom Wheeler issued a statement that the agency is “considering all options,” including an appeal to the U.S. Supreme Court. Sen. Al Franken (D-Minn.) wrote a letter to the agency, requesting that it “act quickly” to “implement new rules that will preserve access to the Internet” as “disastrous” consequences could result from the D.C. Circuit’s opinion. And Sen. Ed Markey (D-Mass.) has also spoken out on the issue, stating his intention to introduce legislation to take the place of the regulations.