Short squeeze

A short squeeze is a rapid price rise that forces short sellers to buy back borrowed shares to close their positions and limit further losses, and that buying itself adds fresh upward pressure on the price, which can force still more shorts to cover, compounding the move. It's a self-reinforcing mechanism. Unlike an ordinary rally driven by new buying alone, a squeeze specifically involves existing short positions being forced to unwind under pressure rather than by their own choice.

Read the setup for a squeeze by looking at short float alongside days to cover (the number of trading days it would take short sellers to buy back their entire position at the stock's average volume) together with a catalyst for renewed buying interest, such as a spike in retail attention or a piece of surprising news. A stock with a high short float and a high days-to-cover figure has more shorts who would need more time to exit if forced, meaning a squeeze in that name, once triggered, has more fuel to run further than one in a stock where shorts could unwind quickly and quietly.

A short squeeze doesn't require any change in the underlying business. It's a positioning-driven price event, not necessarily a reflection of improving fundamentals, and prices that rise on a squeeze can give back much or all of the move once the forced buying is exhausted. It's also not predictable in timing from short float and days-to-cover alone. Those numbers describe vulnerability, not a trigger, and a heavily shorted stock with high days-to-cover can sit unchanged for a long stretch without any squeeze materializing if nothing forces the shorts' hand.

Picture a stock with a 35% short float and 6 days-to-cover that suddenly gains 40% in two sessions on a surprise contract announcement. Shorts who entered near the prior price are now sitting on large losses, and with 6 days-to-cover worth of positions needing to exit, some start buying back shares immediately to cap the damage rather than risk it worsening, adding more buying pressure on top of the news-driven move itself. That combination is what separates a squeeze from an ordinary good-news rally. The stock's move is being amplified by forced covering on top of whatever buying the news alone would have produced.