optionMONSTER's monitoring systems detected the sale 7,997 April 17 calls for the $0.37 bid price. The previous open interest was just 49, so this was a new opening position.
Given that that calls are at the money, they were almost certainly traded against a long position in NLY shares. The investor probably wants to collect the rich dividend of 13 percent and is using the options to reduce the position's volatility. See the discussion of covered calls in our Education Section for more.
NLY rose 0.18 percent to $17.11 in morning trading. It began the month near its 2012 highs of about $17.50, then slipped, rebounded and has been in a tight range for the last two weeks.
