The U.S. Court of Appeals for the Federal Circuit said that the U.S. International Trade Commission erred in how it defined critical terms in the two patents in the complaint, and sent the case back to the ITC for reconsideration.

InterDigital's shares closed up 14.2 percent to $31.18 on Wednesday.

Both of the patents involve wireless cellular technology.

InterDigital filed the complaint at the ITC in 2007, and the ITC ruled that Nokia did not infringe. The Federal Circuit decision means that the ITC will take up the case again.

In July 2011, InterDigital said it was looking into a possible sale of the company but it said in January that it had failed to find takers.

In June this year, InterDigital said it had agreed to sell about 1,700 wireless technology patents for $375 million to Intel Corp.

InterDigital, which primarily licenses technology, had second quarter revenues of $71.9 million, and $301.7 million for fiscal 2011.

The case at the Federal Circuit is No. 2010-1093. The case at the ITC is No. 337-613.

(Reporting By Diane Bartz; Editing by Tim Dobbyn, Bernard Orr)

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