UPDATE 1-US court rules against Argentina over debt fix

* Argentina treated bondholders unequally--court

* Bondholders who didn't join swaps said deserve payment

* Decision could affect future sovereign restructurings

NEW YORK, Oct 26 (Reuters) - A U.S. appeals court said Argentina discriminated against bondholders who refused to take part in massive debt restructurings in 2005 and 2010 by deciding to pay them later than bondholders who agreed to participate.

Friday's decision by the 2nd U.S. Circuit Court of Appeals in New York stems from Argentina's roughly $100 billion default in 2002, and could affect how easily countries trying to extricate themselves from sovereign debt crises might in the future fend off angry creditors.

A unanimous three-judge appeals court panel said that in conducting the restructurings, Argentina violated a provision in the bonds that required it to treat bondholders equally, even if they chose to hold out.

It said U.S. District Judge Thomas Griesa in Manhattan correctly issued injunctions in February requiring equal treatment for holdouts, including NML Capital Ltd and the Aurelius Capital Management funds, that owned $1.4 billion of defaulted debt.

``Nothing in the record supports Argentina's blanket assertion that the injunctions will plunge the Republic into a new financial and economic crisis,'' Circuit Judge Barrington Parker wrote for the panel.

Argentina and the plaintiffs were not immediately available to comment.

The 2nd Circuit did ask Griesa to clarify how the injunctions' payment formula is intended to work, and how the injunctions apply to third parties such as intermediary banks.

More than 90 percent of Argentina's defaulted debt has been restructured.

The case is NML Capital Ltd et al v. Argentina, 2nd U.S. Circuit Court of Appeals, No. 12-105.