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Huge call sale hits National Oilwell

Chris McKhann (chris.mckhann@optionmonster.com)

Heavy call selling leads today's option activity in National Oilwell Varco.

optionMONSTER systems show that 19,500 August 75 calls were sold in one print for the bid price of $4.55. This is clearly a new positions, as open interest was just 356 contracts before the trade appeared.

These options were almost certainly sold against long stock in a covered call , given how close the strike is to the stock price. The trader may well be looking to sell a long-stock position but collect the call premium in doing so. (See our Education section)

NOV is up 1.49 percent to $74.75 in early afternoon trading. The oilfield-services company was at a high of $84.71 in mid-November but bounced off support around $73 on Wednesday.

Today's big put sale has pushed total option volume in NOV past 25,500 contracts so far today, nearly 4 times its daily average for the last month.

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