UPDATE 2-MetroPCS challenges new U.S. Internet traffic rules

* MetroPCS second company to file appeal to Internet rules

* Criticism of 4G data plans a factor in appeal decision

* D.C. Circuit seen favorable forum for rules' opponents (Adds public interest group quote, detail from court filing)

By Jasmin Melvin

WASHINGTON, Jan 25 (Reuters) - MetroPCS Communications PCS.N became the second company to challenge the U.S. Federal Communications Commission's new Internet traffic rules, following Verizon Communications' (VZ.N) appeal last week.

The fifth-largest U.S. wireless carrier said on Tuesday that criticism of its new 4G data plans had been among the factors leading to its decision to appeal to the same court -- the U.S. Court of Appeals for the District of Columbia.

Public interest groups earlier this month had accused MetroPCS of discriminating against some Internet content, applications and websites with its new data plans.

A divided FCC voted 3-2 on Dec. 21 for the Internet rules that forbid broadband providers from blocking legal content but recognize their need to manage their networks and allows them to charge consumers based on levels of usage.

The rules, which provided additional flexibility for wireless providers, have still not been published in the Federal Register.

But MetroPCS, like Verizon, has appealed now, arguing the rules would modify wireless licenses they hold. Both companies accuse the FCC of overstepping its authority. [ID:nN20157175]

"MetroPCS is committed to promoting competition and an open Internet by giving consumers choices for wireless Internet access services at prices they can afford," Chief Executive Roger Linquist said in a statement on Tuesday.

Linquist said concerns over the FCC's jurisdiction, the Verizon appeal, and the criticism of the company's new 4G rate plans prompted the appeal, which was dated Monday.

Free Press, one of the groups that raised concerns over the 4G plans, said MetroPCS had previously indicated it would respond to their allegations by Feb. 11.

"Like a thief caught red-handed, MetroPCS -- rather than change its ways -- is now trying to legalize stealing," M. Chris Riley, policy counsel for Free Press, said of the court filing.

The FCC's split vote over the rules highlighted a huge divide between those who say the Internet will flourish without regulation and those who argue the power of high-speed Internet providers to discriminate against competitors needs to be restrained. [ID:nN21259466]

The D.C. appeals court is viewed as a favorable venue for challenging FCC rules. The same court decided last year that the FCC lacked the authority to stop Comcast Corp (CMCSA.O) from blocking bandwidth-hogging applications on its broadband network, spurring the agency's most recent rulemaking effort.

Disputes over airwaves licenses are only heard by the D.C. appeals court and must be filed within 30 days of the release of an FCC order. Monday marked the deadline for such filings.

Stifel Nicolaus analysts said in a research note that public interest groups and other proponents of the open Internet rules may file legal challenges in other appeals courts to reduce the chances that the D.C. court ultimately hears the case. (Reporting by Jasmin Melvin; Editing by Tim Dobbyn)