$UAL call prices surge fourfold

United Continental shares flew higher on strong quarterly results today, handing huge gains to bullish option traders.

On July 2, Investitute’s market scanners identified the purchase of 1,500 July $70 calls for $2.39 and $2.40 as part of a bullish roll with shares at $69.88. This was clearly a new position, as volume was above the strike’s open interest of 1,290 contracts.

Those calls traded up to $9.23 today, nearly 4 times their purchase prices. The stock rose 13.3% in the same time frame, showing how quickly options can far outperform their underlying shares.

Long calls lock in the price where investors can buy a stock, letting them position for a rally at limited cost with the potential for significant leverage. They carry less risk than owning shares because the most that can be lost is the price of the options no matter how far the stock might fall.

UAL jumped 8.79% today to close at $79 even. The airline carrier topped quarterly estimates and raised its outlook after the market closed yesterday.