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What: Shares of Pendrell (Nasdaq: PCO) are tanking today, down by as much as half, on continued fallout from unfavorable legal news released last Friday after the market close.

So what: Late Friday evening, Pendrell announced that a court of appeals had overturned a 2008 jury verdict in litigation between its subsidiary ICO Global Communications and Boeing (NYSE: BA). The court also awarded Boeing its appellate costs.

Now what: In October 2008, ICO was awarded $603 million due to a Boeing subsidiary being found guilty of fraud and breach of contract; it was ruled that Boeing had interfered with ICO's contractual rights regarding a satellite communications network. Boeing appealed in 2009. Pendrell CEO Ben Wolff said, "We are clearly disappointed with the court's decision and we are evaluating our options for further review."

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