Owning puts locks in the price where the investor can sell shares in the little-known gaming company. If the stock tanks, those contracts will shoot up in value and generate significant leverage on a percentage basis. But if it doesn't fall, the long puts will expire worthless.
Penn shares fell 1.12 percent to $39.85 on Friday. It had been grinding higher since late 2008, but declined between June and August — the same time that the broader market was rallying. It then proceeded to make a lower high below the same $44 level that was support in the spring. That kind of price action could make some chart watchers think that sellers are taking over.
More than 4,600 contracts traded in the session, 33 times greater than average, according to OptionMonster data.
—By CNBC Contributor David Russell
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David Russell is a reporter and writer for OptionMonster. Russell has no positions in PENN.