SPRO
Spero Therapeutics, Inc. Common Stock
stockNASDAQ
At CloseOct 2, 2026 3:59:56 PM EDT
1.19USD-5.556%(-0.07)906,916
Pre-marketOct 2, 2026 8:37:30 AM EDT
1.25USD-0.794%(-0.01)
After-hoursOct 2, 2026 4:01:30 PM EDT
1.20USD+0.840%(+0.01)
As of 2026-09-15, there were 976,488 shares short with a short interest of 2.11%.
SPRO Short Interest - Official
Short Interest
SPRO Short Position Change - Official
Short Position Change
SPRO Short Interest - Official
| Settlement Date1 | Short Interest % | Short Position | Days to Cover2 | Short Position Change | Short Position Change % | Shares Out | Shares Float |
|---|---|---|---|---|---|---|---|
| 2026-09-15 | 2.11 | 976,488 | 3.06 | -233,929 | -19.33 | 58,234,827 | 46,382,570 |
| 2026-08-31 | 2.61 | 1,210,417 | 2.95 | -235,462 | -16.29 | 58,234,827 | 46,382,570 |
| 2026-08-14 | 3.12 | 1,445,879 | 1.90 | -67,475 | -4.46 | 58,234,827 | 46,382,570 |
| 2026-07-31 | 3.26 | 1,513,354 | 1.00 | -600,581 | -28.41 | 57,901,493 | 46,382,570 |
| 2026-07-15 | 4.56 | 2,113,935 | 1.28 | -750,915 | -26.21 | 57,901,493 | 46,382,570 |
| 2026-06-30 | 6.16 | 2,864,850 | 1.04 | +1,033,137 | +56.40 | 57,901,493 | 46,522,113 |
| 2026-06-15 | 3.94 | 1,831,713 | 2.25 | +184,416 | +11.20 | 57,901,493 | 46,522,113 |
| 2026-05-15 | 3.48 | 1,647,297 | 2.61 | +467,595 | +39.64 | 57,901,493 | 47,340,840 |
| 2026-04-30 | 2.56 | 1,179,702 | 3.06 | +441,982 | +59.91 | 57,901,493 | 46,006,105 |
| 2026-04-15 | 1.60 | 737,720 | 1.39 | +132,409 | +21.87 | 57,891,493 | 46,006,105 |
| 2026-03-31 | 1.32 | 605,311 | 1.86 | +67,900 | +12.63 | 57,891,493 | 46,006,105 |
| 2026-03-13 | 1.17 | 537,411 | 1.72 | -36,616 | -6.38 | 56,339,295 | 46,006,105 |
| 2026-02-27 | 1.25 | 574,027 | 2.12 | -141,667 | -19.79 | 56,339,295 | 46,006,105 |
| 2026-02-13 | 1.56 | 715,694 | 1.68 | -225,965 | -24.00 | 56,339,295 | 46,006,105 |
| 2026-01-30 | 2.05 | 941,659 | 4.01 | -97,954 | -9.42 | 56,339,295 | 46,006,105 |
| 2026-01-15 | 2.26 | 1,039,613 | 4.43 | +92,846 | +9.81 | 56,339,295 | 46,006,105 |
| 2025-12-31 | 2.06 | 946,767 | 3.85 | -109,246 | -10.35 | 56,339,295 | 46,006,105 |
| 2025-12-15 | 2.30 | 1,056,013 | 3.51 | +230,315 | +27.89 | 56,339,295 | 46,006,105 |
| 2025-11-28 | 1.79 | 825,698 | 2.14 | +209,963 | +34.10 | 56,339,295 | 46,006,105 |
| 2025-11-14 | 1.34 | 615,735 | 1.05 | +139,598 | +29.32 | 56,275,225 | 45,976,296 |
| 2025-10-31 | 1.18 | 476,137 | 1.00 | +160,422 | +50.81 | 56,275,225 | 40,311,782 |
| 2025-10-15 | 0.82 | 315,715 | 1.00 | -233,758 | -42.54 | 56,275,225 | 38,587,566 |
Historical data is split-adjusted.
1 Data from Finra. Finra publishes an updated file every two weeks.
2 Days to Cover (DTC) is also called Short Ratio. This is the Short Position / Average Daily Trading Volume.