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Ultra Clean Holdings, Inc.

UCTT
Exchange
Nasdaq
Industry
Semiconductors & Related Devices
SEC CIK
0001275014

No open-market purchases or sales by Ultra Clean Holdings, Inc. insiders were filed in the last 90 days; 440 institutions reported holding it in 13F filings for Q2 2026, worth $6.50B in total; Maverick Capital is the only superinvestor holding 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
3.82M
Shares, settlement Oct 30, 2026
Change
+566.6K
+17.4% vs. Oct 15, 2026
Days to cover
2.25
Short interest ÷ average daily volume
Average daily volume
1.70M
Shares, as reported by FINRA
Short interest by settlement date
Oct 31, 2024: 998,117 sharesNov 15, 2024: 918,541 sharesNov 29, 2024: 1,009,876 sharesDec 13, 2024: 1,177,517 sharesDec 31, 2024: 1,193,135 sharesJan 15, 2025: 1,203,712 sharesJan 31, 2025: 1,112,306 sharesFeb 14, 2025: 977,319 sharesFeb 28, 2025: 989,729 sharesMar 14, 2025: 1,089,358 sharesMar 31, 2025: 1,085,904 sharesApr 15, 2025: 1,326,453 sharesApr 30, 2025: 1,486,437 sharesMay 15, 2025: 1,427,072 sharesMay 30, 2025: 1,358,140 sharesJun 13, 2025: 1,214,023 sharesJun 30, 2025: 1,286,110 sharesJul 15, 2025: 1,447,651 sharesJul 31, 2025: 1,414,908 sharesAug 15, 2025: 1,540,194 sharesAug 29, 2025: 1,494,779 sharesSep 15, 2025: 1,530,077 sharesSep 30, 2025: 1,594,675 sharesOct 15, 2025: 1,551,674 sharesOct 31, 2025: 1,427,421 sharesNov 14, 2025: 1,590,611 sharesNov 28, 2025: 1,900,337 sharesDec 15, 2025: 2,136,392 sharesDec 31, 2025: 2,189,838 sharesJan 15, 2026: 2,543,039 sharesJan 30, 2026: 2,314,795 sharesFeb 13, 2026: 2,114,454 sharesFeb 27, 2026: 2,525,785 sharesMar 13, 2026: 3,032,105 sharesMar 31, 2026: 2,871,465 sharesApr 15, 2026: 2,616,992 sharesApr 30, 2026: 2,423,873 sharesMay 15, 2026: 2,921,707 sharesMay 29, 2026: 3,073,344 sharesJun 15, 2026: 3,502,511 sharesJun 30, 2026: 3,221,999 sharesJul 15, 2026: 3,555,892 sharesJul 31, 2026: 3,343,289 sharesAug 14, 2026: 3,155,174 sharesAug 31, 2026: 3,611,264 sharesSep 15, 2026: 3,618,539 sharesSep 30, 2026: 3,714,027 sharesOct 15, 2026: 3,254,534 sharesOct 30, 2026: 3,821,097 shares
Short interest in UCTT by settlement date
Settlement dateShort interestChangeChange %Avg. daily volumeDays to cover
Oct 30, 20263.82M+566.6K+17.4%1.70M2.25
Oct 15, 20263.25M−459.5K−12.4%1.45M2.24
Sep 30, 20263.71M+95.5K+2.6%837.1K4.44
Sep 15, 20263.62M+7.28K+0.2%824.7K4.39
Aug 31, 20263.61M+456.1K+14.5%867.4K4.16
Aug 14, 20263.16M−188.1K−5.6%1.38M2.29
Jul 31, 20263.34M−212.6K−6.0%1.38M2.43
Jul 15, 20263.56M+333.9K+10.4%1.65M2.16
Jun 30, 20263.22M−280.5K−8.0%1.57M2.05
Jun 15, 20263.50M+429.2K+14.0%1.31M2.68
May 29, 20263.07M+151.6K+5.2%1.03M2.99
May 15, 20262.92M+497.8K+20.5%1.10M2.66
Apr 30, 20262.42M−193.1K−7.4%988.2K2.45
Apr 15, 20262.62M−254.5K−8.9%895.6K2.92
Mar 31, 20262.87M−160.6K−5.3%1.11M2.59
Mar 13, 20263.03M+506.3K+20.1%1.45M2.09
Feb 27, 20262.53M+411.3K+19.5%2.44M1.03
Feb 13, 20262.11M−200.3K−8.7%1.20M1.76
Jan 30, 20262.31M−228.2K−9.0%1.06M2.19
Jan 15, 20262.54M+353.2K+16.1%1.25M2.03
Dec 31, 20252.19M+53.4K+2.5%335.7K6.52
Dec 15, 20252.14M+236.1K+12.4%640.2K3.34
Nov 28, 20251.90M+309.7K+19.5%498.3K3.81
Nov 14, 20251.59M+163.2K+11.4%446.8K3.56
Oct 31, 20251.43M−124.3K−8.0%513.7K2.78
Oct 15, 20251.55M−43.0K−2.7%447.3K3.47
Sep 30, 20251.59M+64.6K+4.2%412.6K3.87
Sep 15, 20251.53M+35.3K+2.4%287.2K5.33
Aug 29, 20251.49M−45.4K−3.0%320.4K4.67
Aug 15, 20251.54M+125.3K+8.9%457.1K3.37
Jul 31, 20251.41M−32.7K−2.3%558.0K2.54
Jul 15, 20251.45M+161.5K+12.6%471.8K3.07
Jun 30, 20251.29M+72.1K+5.9%603.5K2.13
Jun 13, 20251.21M−144.1K−10.6%581.7K2.09
May 30, 20251.36M−68.9K−4.8%362.9K3.74
May 15, 20251.43M−59.4K−4.0%641.2K2.23
Apr 30, 20251.49M+160.0K+12.1%688.1K2.16
Apr 15, 20251.33M+240.5K+22.2%667.0K1.99
Mar 31, 20251.09M−3.45K−0.3%479.4K2.27
Mar 14, 20251.09M+99.6K+10.1%782.5K1.39
Feb 28, 2025989.7K+12.4K+1.3%763.2K1.30
Feb 14, 2025977.3K−135.0K−12.1%281.5K3.47
Jan 31, 20251.11M−91.4K−7.6%362.3K3.07
Jan 15, 20251.20M+10.6K+0.9%300.3K4.01
Dec 31, 20241.19M+15.6K+1.3%309.8K3.85
Dec 13, 20241.18M+167.6K+16.6%308.8K3.81
Nov 29, 20241.01M+91.3K+9.9%324.4K3.11
Nov 15, 2024918.5K−79.6K−8.0%431.1K2.13
Oct 31, 2024998.1K+143.3K+16.8%588.1K1.70

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 UCTT by settlement date
Settlement dateSharesPriceValue
Oct 14, 20268,750$61.02$533.9K
Oct 6, 202610$74.02$740.2
Oct 5, 202623,400$72.69$1.70M
Sep 30, 202620$80.46$1.61K
Sep 22, 20268,758$73.05$639.8K
Sep 21, 20265,157$70.64$364.3K
Sep 11, 2026754$71.13$53.6K
Sep 3, 20263,485$66.07$230.3K
Aug 11, 202658$82.27$4.77K
Aug 5, 202621$84.54$1.78K
Aug 4, 20261,061$89.17$94.6K
Jul 16, 202664$102.11$6.54K
Jul 14, 202698$98.25$9.63K
Jul 6, 202618,989$106.48$2.02M
Jul 2, 20265,487$129.59$711.1K
Jun 29, 202611,457$118.82$1.36M
Jun 24, 202611,325$111.63$1.26M
Jun 23, 2026100$123.14$12.3K
Jun 22, 20267,141$121.28$866.1K
Jun 18, 202649$111.61$5.47K
Jun 10, 202644$91.88$4.04K
Jun 4, 20266$92.55$555.3
Jun 3, 202619$90.21$1.71K
May 29, 202657$87.29$4.98K
May 26, 202665$84.01$5.46K
May 18, 2026199$85.94$17.1K
May 13, 202617,869$82.99$1.48M
May 4, 20267$74.61$522.27
Apr 30, 20261,226$72.01$88.3K
Apr 24, 2026277$78.24$21.7K

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 UCTT by trade date
Trade dateShort volumeShort exemptOff-exchange volumeShort volume ratio
Nov 11, 2026225,412100432,02952.2%
Nov 10, 2026190,799431374,69850.9%
Nov 9, 2026241,4534401,86760.1%
Nov 6, 2026715,36120,7061,131,44763.2%
Nov 5, 2026781,32321,9721,269,45561.5%
Nov 4, 2026264,444163615,28043.0%
Nov 3, 2026147,5011,882402,34036.7%
Nov 2, 2026184,3627,237609,43130.3%
Oct 30, 2026258,83511,218790,47432.7%
Oct 29, 2026437,6340815,57053.7%
Oct 28, 2026933,047371,777,50652.5%
Oct 27, 2026470,5870752,36362.5%
Oct 26, 2026212,7072,501465,88545.7%
Oct 23, 2026188,37010,032433,36243.5%
Oct 22, 2026259,66423,782720,43636.0%
Oct 21, 2026130,8025305,73142.8%
Oct 20, 2026166,8840442,74537.7%
Oct 19, 2026184,4140510,71336.1%
Oct 16, 2026106,840447458,93723.3%
Oct 15, 2026190,323107678,61828.0%
Oct 14, 2026177,990265598,52329.7%
Oct 13, 2026239,3251371,043,17022.9%
Oct 12, 2026222,7260540,75641.2%
Oct 9, 2026103,3070287,06136.0%
Oct 8, 2026214,6675580,03637.0%
Oct 7, 2026117,017307282,37141.4%
Oct 6, 2026164,53777386,39042.6%
Oct 5, 2026241,7437512,07547.2%
Oct 2, 2026339,95210792,83842.9%
Oct 1, 2026148,2781,332410,09936.2%

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 UCTT
Week ofTierATS sharesATS tradesOther OTC sharesOther OTC tradesATS share
Oct 5, 2026T21,389,65236,6491,472,60512,25448.6%
Sep 28, 2026T21,679,85642,774989,30712,57062.9%
Sep 21, 2026T2961,05232,172670,18110,31158.9%
Sep 14, 2026T2741,82427,069753,49310,01449.6%
Sep 7, 2026T21,046,33325,627583,2197,61564.2%
Aug 31, 2026T21,288,24535,7201,171,19311,57852.4%
Aug 24, 2026T2962,18428,634517,52810,53665.0%
Aug 17, 2026T21,671,23246,134790,06010,41467.9%
Aug 10, 2026T21,427,80037,978789,66312,31364.4%
Aug 3, 2026T22,649,57060,0351,351,11116,40366.2%
Jul 27, 2026T22,856,44974,3691,356,58028,41067.8%
Jul 20, 2026T21,231,79535,497848,14711,54359.2%