Note: The Skinny blog is written by Rick Smith, editor and co-founder of Local Tech Wire and business editor of WRAL.com.

RESEARCH TRIANGLE PARK, N.C. – As bankrupt prepares to auction off its Voice over Internet Protocol business unit this week, the company faces another legal fight.

The latest skirmish for the company’s remnants and assets came over the weekend with the news that the regulator of pensions in the United Kingdom has filed a $3 billion claim against Nortel. Nortel has some 43,000 retired workers in the U.K. and their pensions are covered by the government as are benefits for Nortel retirees in the U.S.

However, , the U.K. pension fund is underfunded and wants some of the proceeds from Nortel’s liquidations.

Nortel recently reached a settlement with retired Canadian workers and others receiving long-term disability payments. But that agreement is being challenged by U.S. creditors. ()

Plus, whether Nortel will be completely liquidated remains unclear. ()

Whether the U.K. regulatory will have legal standing is unclear, the Toronto newspaper reported.

Nortel told Globe and Mail that it would fight the move. “Any claims the U.K. Pensions Regulator has should be addressed through the court-approved claims process,” the company said.

Meanwhile, Nortel’s liquidation continues this week. Competing bids for the VoIP unit are due on Feb. 23 and the auction is set for Feb. 25.

Texas-based Genband received “stalking horse bid” approval from the U.S. and Canadian bankruptcy courts in January for its offer of $282 million. That status gives Genband the right to match other offers.

Nortel still maintains an operation RTP.

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