Alcoa attracts heavy put selling

The big option trade in Alcoa today is short puts, even as shares pull back from their six-month highs.

AA trades at $12.66, down 0.25 percent on the day and pushing back against support that has been holding up--though tested daily--for the last few weeks. The aluminum producer's stock hit $13.49 three weeks ago, its highest price since April.

Leading today's volume is one print in the April 13 puts, as trader sold 9,500 of them for $1.41. This volume was more than the previous open interest at this strike, so it was a new opening position.

Selling slightly in-the-money puts indicates that the trader is willing to buy shares at this level. The position will make roughly 10 percent in the next six months if shares remain in this range.