Bears want to hammer Masco Chris McKhann , analyst at OptionMonster.NEW YORK -- Masco ( MAS) fell Thursday, and traders looked for more downside. OptionMonster's tracking programs detected the purchase of more than 13,000 May 18 puts, almost all of which priced for 60 cents. These are clearly new positions, as the volume was more than 40 times the strike's open interest before the session began. Puts lock in the price where investors can sell shares in the home-improvement company, which have been edging lower since March 20. These options stand to generate significant leverage to the downside if the stock continues to fall, so they might be hedging a long position or just betting on a drop. Masco's shares ended the session down 1.11% to $18.79. There is some support at the $18 level, but continued selling could quickly push it to $16. The company is scheduled to report earnings on April 30. Total option volume was 14 times greater than average Thursday, with puts outnumbering calls by more than 21 to 1. McKhann has no positions in MAS.