UPB
Upstream Bio, Inc. Common Stock
stockNASDAQ
Market OpenOct 5, 2026 11:44:28 AM EDT
4.68USD-7.228%(-0.37)282,057
4.6800Bid4.6900Ask0.0100SpreadAs of 2026-09-15, there were 4,490,724 shares short with a short interest of 22.36%.
UPB Short Interest - Official
Short Interest
UPB Short Position Change - Official
Short Position Change
UPB 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 | 22.36 | 4,490,724 | 6.84 | +395,713 | +9.66 | 54,771,041 | 20,083,581 |
| 2026-08-31 | 20.39 | 4,095,011 | 7.45 | +78,397 | +1.95 | 54,771,041 | 20,083,581 |
| 2026-08-14 | 20.00 | 4,016,614 | 5.64 | +368,056 | +10.09 | 54,771,041 | 20,083,581 |
| 2026-07-31 | 18.17 | 3,648,558 | 7.49 | +30,407 | +0.84 | 54,419,986 | 20,083,581 |
| 2026-07-15 | 18.02 | 3,618,151 | 8.18 | -487,479 | -11.87 | 54,419,986 | 20,083,581 |
| 2026-06-30 | 20.44 | 4,105,630 | 5.72 | +207,401 | +5.32 | 54,419,986 | 20,083,581 |
| 2026-06-15 | 19.41 | 3,898,229 | 5.48 | +500,470 | +14.73 | 54,419,986 | 20,083,581 |
| 2026-05-15 | 16.92 | 3,397,759 | 6.69 | +174,137 | +5.40 | 54,419,986 | 20,083,581 |
| 2026-04-30 | 16.16 | 3,223,622 | 5.71 | +200,728 | +6.64 | 54,419,986 | 19,942,455 |
| 2026-04-15 | 15.16 | 3,022,894 | 5.24 | -412,367 | -12.00 | 54,419,986 | 19,942,455 |
| 2026-03-31 | 17.23 | 3,435,261 | 3.46 | -1,317,093 | -27.71 | 54,419,986 | 19,942,455 |
| 2026-03-13 | 23.83 | 4,752,354 | 4.44 | +665,977 | +16.30 | 54,038,591 | 19,942,455 |
| 2026-02-27 | 20.49 | 4,086,377 | 1.83 | +556,580 | +15.77 | 54,038,591 | 19,942,455 |
| 2026-02-13 | 17.70 | 3,529,797 | 1.52 | +345,913 | +10.86 | 54,038,591 | 19,942,455 |
| 2026-01-30 | 15.97 | 3,183,884 | 5.54 | -267,660 | -7.75 | 54,038,591 | 19,942,455 |
| 2026-01-15 | 17.31 | 3,451,544 | 5.29 | -35,056 | -1.01 | 54,038,591 | 19,942,455 |
| 2025-12-31 | 17.48 | 3,486,600 | 5.75 | +503,032 | +16.86 | 54,038,591 | 19,942,455 |
| 2025-12-15 | 14.96 | 2,983,568 | 5.58 | +209,933 | +7.57 | 54,038,591 | 19,942,455 |
| 2025-11-28 | 13.91 | 2,773,635 | 5.12 | -220,421 | -7.36 | 54,038,591 | 19,942,455 |
| 2025-11-14 | 15.01 | 2,994,056 | 7.81 | +64,580 | +2.20 | 54,038,591 | 19,942,455 |
| 2025-10-31 | 14.72 | 2,929,476 | 7.88 | -407,437 | -12.21 | 53,909,427 | 19,894,789 |
| 2025-10-15 | 16.77 | 3,336,913 | 10.27 | -227,304 | -6.38 | 53,909,427 | 19,894,789 |
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.