Short interest (SI)
The total number of shares that have been sold short and not yet bought back. It is a snapshot of how big the bet against a stock is — but it publishes on a schedule, twice a month, with a lag of more than a week. By the time you read it, the picture may already have changed.
Published per settlement date, semi-monthly, never live. Two traps: the headline can hide positions that are hedges rather than directional bets (a Convertible-arb hedge sits inside SI but cannot be squeezed out), and "percent of float" depends entirely on which share count you divide by — the same position can be described as a third of shares outstanding or three quarters of the true free float, simultaneously, without either number being false. Decompose before you conclude. Daily Short volume does NOT update this figure, and Days to cover (DTC) is derived from it.
Used in
- Doximity Doubles Overnight: Squeeze or Re-Rating? Why the Difference Decides Everything — Short interest as amplifier, not cause
- The Hertz 'Squeeze' That Wasn't: Reading Positioning Before You Pay for It — Was there actually a squeeze? The three checks
- Short-Squeeze Forensics: The Method — Decompose the headline short interest
- Short-Squeeze Forensics: The Method — Short volume cannot show covering