Quick definition A short squeeze occurs when short sellers are forced to buy back (cover) their positions, pushing prices higher. This can create a rapid price spike if many short sellers cover simultaneously. What it is A short squeeze has two components: a large short position and circumstances that force short sellers to cover. Forcing mechanisms include: - Borrowed shares become unavailable to borrow - Lenders recall borrowed shares - Prices rise so much that short sellers cut losses - Margin calls force liquidation Why it matters Short squeezes can create extreme price moves. Prices can spike 50 percent or more in days. Short sellers can face catastrophic losses. Short squeezes are often accompanied by retail investor enthusiasm. Recent meme stocks (GameStop, AMC) experienced short squeezes when retail investors coordinated buying. Characteristics Short squeezes typically show: - Large open short position - High borrow fee (shares hard to borrow) - Rapid price increase - High trading volume - Short sellers covering Practical example A stock has 50 million shares of short interest (short sellers collectively short 50 million shares). Shares are hard to borrow; the borrow fee is 20 percent annually. A positive catalyst emerges (good earnings, new product). Retail investors start buying. The price rises 10 percent in a day. Short sellers panic and start covering. Buying pressure from covering accelerates the price move. The price rises another 20 percent the next day as the squeeze intensifies. The stock eventually settles at a new equilibrium, but not before spiking significantly. Risks Short squeezes are dangerous for short sellers. A position can go underwater very quickly. Margin calls can force liquidation at the worst prices. Short squeezes also concern regulators because they can destabilise markets. See also - Short Sale - Short Covering - Gamma Squeeze - Margin Call
