About Spero Therapeutics, Inc. (SPRO) data
Data as of September 30, 2026.
Spero Therapeutics, Inc. (SPRO) has 794.51K shares sold short as of the latest FINRA settlement report on September 30, 2026. Short interest has decreased by 18.64% compared with the prior settlement. At the current average daily volume, covering all open short positions would take about 0.69 days (days to cover).
Frequently asked questions
What is the current short interest in SPRO?
As of the latest FINRA settlement dated September 30, 2026, SPRO had approximately 794,509 shares sold short. Short interest data is reported by FINRA twice per month.
How much does it cost to short SPRO?
The latest borrow fee (cost to borrow) for SPRO is 0.31% per year, based on IBKR data. Fees can change throughout the trading day as shares are borrowed and returned.
What is the days to cover ratio for SPRO?
Days to cover for SPRO is approximately 0.69 days. This estimates how many trading days it would take short sellers to buy back all outstanding short shares at the current average daily volume.
Is SPRO a short squeeze candidate?
A squeeze needs shorts that are hard to close. SPRO trades about 1,144,097 shares a day and would take roughly 0.69 days to unwind current short positions, at a current borrow fee of 0.31%. Higher days-to-cover and a rising borrow fee together are the setup to watch; neither alone is enough.