Stocks to Watch: NAV, GRPN, TRV & More

Take a look at some of Tuesday's midday movers:

market-insider-stocks-to-watch-200.jpg

Navistar moved higher after billionaire investor Carl Icahn issued another open letter to the company's shareholders in which he said that his previous comments were demands, not threats, that should be taken seriously.

Groupon moved higher after data from ComScore showed an increase in traffic to its website.

Travelers hit an all-time high after its CEO said insurance rate continued to rise in the third quarter for both businesses and individual customers.

Luxury retailers, including Tiffany, Ralph Lauren and Coach fell after Burberryissued an earnings warning.

Symbol
Price
 
Change
%Change
TIF
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RL
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TPR
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Morgan Stanley and Citigroup rose after Morgan agreed to buy the rest of its brokerage joint venture from Citi over time for about $13.5 billion.

Sirius Radio moved lower after widely-followed investor Mario Gabelli downgraded the stock to "sell" from "hold."

Energy stocks, including Cabot, Marathon, Hess, Chesapeake, Halliburton, and National Oilwell Varco rose as natural gas prices jumped for a second-straight day.

Symbol
Price
 
Change
%Change
COG
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MRO
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ICTXX
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CHI
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HAL
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NOV
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Amarin continued to fall after the biotech company told investors it doesn’t expect a decision from the FDA this month on its heart pill, Vascepa.

Sunesis Pharmaceuticals soared to a two-year high after the company said a recommendation from an independent committee on its experimental blood cancer drug would trigger a $25 million investment by Royalty Pharma.

Tibco Software slid after ThinkEquity cut its rating on the stock to "hold" from "buy," saying job cuts are likely to happen soon.

Sallie Mae moved higher after CEO Al Lord said at a Barclay’s conference that the stock is too low, leading to speculation of more buybacks.

Mellanox Technologies popped following reports that the company was approached by multiple buyers over the past year, according to Reuters, citing an interview with the company's CEO.

United Natural Foods fell after its fourth-quarter earnings came in below analysts’ estimates.

El Paso Pipeline Partners moved lower after the company began an offering of 7.1 million units representing limited partner interests.

Polypore fell after the filtration products maker warned that its third-quarter earnings would come in below forecasts.

—By CNBC's Rich Fisherman.

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