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What: Shares of Rovi (Nasdaq: ROVI) lost nearly half their value today, down by as much as 44%, after the company reported preliminary results and updated its full-year outlook last night.

So what: Second-quarter sales are expected at $158 million, lower than the $179 million seen a year ago. The company's losses are expected to widen to between $0.15 and $0.18 per share, also worse than the loss of $0.06 last time around. The consumer electronics segment's sales were hurt by fewer licensed manufacturers than expected and falling royalty-bearing unit sales.

Now what: As a result, Rovi is also slashing its full-year outlook, with revenue now expected in the range of $650 million to $680 million, with adjusted earnings per share of $1.60 to $1.90. That's a reduction of nearly a third as demand in its consumer electronics segment dries up. Rovi saw delays in inking new patent licensees, and while it prefers not to litigate, it's been unable to negotiate licenses with some manufacturers.

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Fool contributor Evan Niu holds no position in any company mentioned. Check out his holdings and a short bio. We Fools don't all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. Try any of our Foolish newsletter services free for 30 days. The Motley Fool has a disclosure policy.