$TWTR call prices triple overnight

It took just 24 hours for bullish option traders to turn big gains in Twitter.

Just yesterday, Investitute’s tracking systems showed that 4,400 Weekly $29.50 calls expiring this Friday were purchased for $0.34 to $0.44 with shares at $28.50. These was clearly fresh buying, as volume was well above the strike’s open interest of 1,107 contracts.

Those calls traded up to $1.18 above today, 3.5 times their initial purchase price. The stock rose 6.3% at the same time, underscoring how quickly options can 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.

TWTR jumped 5.43% to $29.53 today. The social-media company rallied along with Facebook, whose CEO testified before Congress this afternoon.