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Zura Bio Ltd

ZURA
Exchange
Nasdaq
Industry
Biological Products, (No Diagnostic Substances)
SEC CIK
0001855644

No open-market purchases or sales by Zura Bio Ltd insiders were filed in the last 90 days; 95 institutions reported holding it in 13F filings for Q2 2026, worth $428.9M in total; no superinvestor holds it.

Four kinds of short-selling data, each measuring something different:

  • Short interest: shares sold short and not yet bought back, as of a settlement date. FINRA publishes it twice a month, about eight business days after the settlement date.
  • Daily short volume: shares sold short each day in off-exchange trades reported to FINRA. It counts trades, not open positions, and is published the next day.
  • Fails-to-deliver: shares not delivered by the settlement date. The SEC publishes them twice a month, about two weeks late.
  • ATS (dark pool) volume: weekly volume on alternative trading systems and other off-exchange venues. FINRA publishes it two to four weeks after the week.

More in the glossary.

Short interest

Shares sold short and not yet bought back, from FINRA, on every settlement date in the last two years.

Short interest
8.47M
Shares, settlement Oct 30, 2026
Change
+1.45M
+20.7% vs. Oct 15, 2026
Days to cover
1.79
Short interest ÷ average daily volume
Average daily volume
4.73M
Shares, as reported by FINRA
Short interest by settlement date
Oct 31, 2024: 1,750,644 sharesNov 15, 2024: 4,956,033 sharesNov 29, 2024: 5,162,995 sharesDec 13, 2024: 5,012,344 sharesDec 31, 2024: 4,952,924 sharesJan 15, 2025: 4,989,992 sharesJan 31, 2025: 4,881,590 sharesFeb 14, 2025: 5,126,526 sharesFeb 28, 2025: 5,228,010 sharesMar 14, 2025: 5,306,073 sharesMar 31, 2025: 5,374,772 sharesApr 15, 2025: 2,588,939 sharesApr 30, 2025: 2,486,468 sharesMay 15, 2025: 2,509,174 sharesMay 30, 2025: 3,075,143 sharesJun 13, 2025: 2,668,914 sharesJun 30, 2025: 1,159,481 sharesJul 15, 2025: 585,928 sharesJul 31, 2025: 534,445 sharesAug 15, 2025: 544,611 sharesAug 29, 2025: 425,343 sharesSep 15, 2025: 458,086 sharesSep 30, 2025: 2,050,530 sharesOct 15, 2025: 2,623,215 sharesOct 31, 2025: 2,718,321 sharesNov 14, 2025: 2,568,554 sharesNov 28, 2025: 2,541,302 sharesDec 15, 2025: 2,599,519 sharesDec 31, 2025: 2,849,707 sharesJan 15, 2026: 3,012,119 sharesJan 30, 2026: 3,847,872 sharesFeb 13, 2026: 4,075,644 sharesFeb 27, 2026: 4,737,248 sharesMar 13, 2026: 5,105,550 sharesMar 31, 2026: 5,754,385 sharesApr 15, 2026: 6,154,548 sharesApr 30, 2026: 6,974,577 sharesMay 15, 2026: 6,241,113 sharesMay 29, 2026: 6,219,823 sharesJun 15, 2026: 5,873,622 sharesJun 30, 2026: 9,242,718 sharesJul 15, 2026: 10,252,606 sharesJul 31, 2026: 10,513,220 sharesAug 14, 2026: 11,440,748 sharesAug 31, 2026: 11,098,438 sharesSep 15, 2026: 9,341,381 sharesSep 30, 2026: 9,365,853 sharesOct 15, 2026: 7,019,394 sharesOct 30, 2026: 8,471,655 shares
Short interest in ZURA by settlement date
Settlement dateShort interestChangeChange %Avg. daily volumeDays to cover
Oct 30, 20268.47M+1.45M+20.7%4.73M1.79
Oct 15, 20267.02M−2.35M−25.1%4.78M1.47
Sep 30, 20269.37M+24.5K+0.3%1.96M4.78
Sep 15, 20269.34M−1.76M−15.8%1.46M6.42
Aug 31, 202611.1M−342.3K−3.0%1.91M5.81
Aug 14, 202611.4M+927.5K+8.8%889.8K12.86
Jul 31, 202610.5M+260.6K+2.5%536.9K19.58
Jul 15, 202610.3M+1.01M+10.9%1.08M9.52
Jun 30, 20269.24M+3.37M+57.4%2.28M4.05
Jun 15, 20265.87M−346.2K−5.6%1.09M5.39
May 29, 20266.22M−21.3K−0.3%685.4K9.08
May 15, 20266.24M−733.5K−10.5%675.7K9.24
Apr 30, 20266.97M+820.0K+13.3%630.6K11.06
Apr 15, 20266.15M+400.2K+7.0%602.6K10.21
Mar 31, 20265.75M+648.8K+12.7%640.5K8.98
Mar 13, 20265.11M+368.3K+7.8%450.8K11.33
Feb 27, 20264.74M+661.6K+16.2%496.3K9.54
Feb 13, 20264.08M+227.8K+5.9%389.8K10.45
Jan 30, 20263.85M+835.8K+27.8%1.15M3.35
Jan 15, 20263.01M+162.4K+5.7%710.3K4.24
Dec 31, 20252.85M+250.2K+9.6%671.9K4.24
Dec 15, 20252.60M+58.2K+2.3%383.0K6.79
Nov 28, 20252.54M−27.3K−1.1%328.5K7.74
Nov 14, 20252.57M−149.8K−5.5%532.9K4.82
Oct 31, 20252.72M+95.1K+3.6%555.1K4.90
Oct 15, 20252.62M+572.7K+27.9%1.69M1.55
Sep 30, 20252.05M+1.59M+347.6%6.07M1.00
Sep 15, 2025458.1K+32.7K+7.7%259.8K1.76
Aug 29, 2025425.3K−119.3K−21.9%405.1K1.05
Aug 15, 2025544.6K+10.2K+1.9%351.5K1.55
Jul 31, 2025534.4K−51.5K−8.8%1.25M1.00
Jul 15, 2025585.9K−573.6K−49.5%522.6K1.12
Jun 30, 20251.16M−1.51M−56.6%869.5K1.33
Jun 13, 20252.67M−406.2K−13.2%641.3K4.16
May 30, 20253.08M+566.0K+22.6%727.9K4.22
May 15, 20252.51M+22.7K+0.9%299.8K8.37
Apr 30, 20252.49M−102.5K−4.0%357.6K6.95
Apr 15, 20252.59M−2.79M−51.8%455.3K5.69
Mar 31, 20255.37M+68.7K+1.3%297.6K18.06
Mar 14, 20255.31M+78.1K+1.5%237.4K22.35
Feb 28, 20255.23M+101.5K+2.0%250.6K20.86
Feb 14, 20255.13M+244.9K+5.0%271.8K18.86
Jan 31, 20254.88M−108.4K−2.2%674.5K7.24
Jan 15, 20254.99M+37.1K+0.8%325.7K15.32
Dec 31, 20244.95M−59.4K−1.2%844.1K5.87
Dec 13, 20245.01M−150.7K−2.9%582.1K8.61
Nov 29, 20245.16M+207.0K+4.2%306.8K16.83
Nov 15, 20244.96M+3.21M+183.1%353.5K14.02
Oct 31, 20241.75M−132.1K−7.0%381.3K4.59

Fails-to-deliver

Shares that weren't delivered by the settlement date, from the SEC, for the last 30 dates with fails. The price is the previous day's closing price published by the SEC.

Fails-to-deliver in ZURA by settlement date
Settlement dateSharesPriceValue
Oct 13, 20262,646$4.00$10.6K
Sep 21, 20269,191$4.46$41.0K
Sep 10, 202618,272$5.71$104.3K
Aug 5, 20264$5.69$22.76
Aug 3, 20261,126$5.43$6.11K
Jul 28, 2026260$5.38$1.40K
Jul 27, 2026226$5.23$1.18K
Jul 23, 20261,303$5.40$7.04K
Jul 17, 202633$5.25$173.25
Jul 10, 20266,498$5.51$35.8K
Jul 9, 20269,011$5.49$49.5K
Jul 2, 20269$5.01$45.09
Jul 1, 202658,683$5.90$346.2K
Jun 30, 202610,120$5.63$57.0K
Jun 11, 202684$3.55$298.2
May 19, 20261,600$4.12$6.59K
May 11, 20261,374$4.79$6.58K
Apr 23, 2026373$5.69$2.12K
Apr 20, 2026100$5.81$581
Apr 17, 20266,908$5.71$39.4K
Apr 2, 202617,182$6.03$103.6K
Mar 3, 202626$6.76$175.76
Feb 20, 20269,966$6.28$62.6K
Feb 4, 2026790$6.32$4.99K
Dec 30, 20254,161$5.35$22.3K
Dec 12, 202514,223$4.04$57.5K
Nov 18, 20252,328$3.99$9.29K
Nov 12, 2025143$4.42$632.06
Nov 4, 202537,800$3.68$139.1K
Oct 27, 20251,022$3.69$3.77K

Daily short volume

Off-exchange short-sale volume, not short interest: shares sold short each day in trades reported to FINRA, for the last 30 trading days.

The short volume ratio isn't a sentiment gauge: market makers sell short to fill buy orders and to hedge, so short sales are usually about half of off-exchange volume.

Off-exchange short volume in ZURA by trade date
Trade dateShort volumeShort exemptOff-exchange volumeShort volume ratio
Nov 10, 20261,644,085231,8289,531,93517.2%
Nov 9, 202620,522,3703,100,54736,588,91856.1%
Nov 6, 2026825,0764,5001,443,46357.2%
Nov 5, 2026732,6723381,284,61257.0%
Nov 4, 2026561,0926,011987,45556.8%
Nov 3, 2026449,5011441,046,00243.0%
Nov 2, 2026893,2523,7051,986,61345.0%
Oct 30, 20261,479,862168,0062,179,87567.9%
Oct 29, 20261,058,46445,8141,712,70261.8%
Oct 28, 2026710,5918,0191,805,63639.4%
Oct 27, 2026913,1912002,640,95834.6%
Oct 26, 20261,201,38418,2272,019,95659.5%
Oct 23, 20261,579,525247,6792,989,42852.8%
Oct 22, 20261,987,29295,9343,981,55349.9%
Oct 21, 2026460,5301,5902,170,65321.2%
Oct 20, 2026420,26101,439,79729.2%
Oct 19, 2026867,9244,0982,216,53939.2%
Oct 16, 20261,304,6735,9942,021,25864.5%
Oct 15, 20261,345,02134,1602,466,27654.5%
Oct 14, 20261,428,76320,6722,703,40552.9%
Oct 13, 20267,107,99114,81412,608,95356.4%
Oct 12, 2026503,0391,881792,04263.5%
Oct 9, 2026253,8811,100565,17944.9%
Oct 8, 2026687,9611,9201,375,49850.0%
Oct 7, 2026582,4490922,52263.1%
Oct 6, 2026475,61714627,97375.7%
Oct 5, 2026423,4111001,683,89725.1%
Oct 2, 2026726,73101,728,17042.1%
Oct 1, 2026671,92001,861,75336.1%
Sep 30, 20261,432,11001,939,52373.8%

ATS (dark pool) volume

Weekly volume on alternative trading systems (ATS) and other off-exchange (OTC) venues, from FINRA, for the last 12 weeks. ATS share is ATS volume ÷ (ATS + OTC volume), not a share of all trading.

Weekly ATS and OTC volume in ZURA
Week ofTierATS sharesATS tradesOther OTC sharesOther OTC tradesATS share
Oct 5, 2026T21,403,45315,4663,869,6635,23226.6%
Sep 28, 2026T21,951,47319,9095,492,7175,27526.2%
Sep 21, 2026T21,939,85216,6672,842,6375,67040.6%
Sep 14, 2026T21,330,38818,4282,236,0225,81637.3%
Sep 7, 2026T2942,60416,0561,123,9004,34445.6%
Aug 31, 2026T21,085,49215,3591,595,4444,66140.5%
Aug 24, 2026T23,019,00025,0235,451,34615,37935.6%
Aug 17, 2026T21,102,68015,222844,1363,14656.6%
Aug 10, 2026T21,677,57820,6801,078,9673,54260.9%
Aug 3, 2026T2825,28417,585844,7233,56049.4%
Jul 27, 2026T2522,40413,165426,0142,37355.1%
Jul 20, 2026T2557,86115,055331,5352,85962.7%