Skip to main content
Livermore
Livermore
US stocksTW
ZHEN

Formfactor Inc

FORM
Exchange
Nasdaq
Industry
Semiconductors & Related Devices
SEC CIK
0001039399

In the last 90 days, Formfactor Inc insiders filed 0 open-market purchases and 4 sales; 514 institutions reported holding it in 13F filings for Q2 2026, worth $11.4B 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
2.82M
Shares, settlement Oct 30, 2026
Change
+198.0K
+7.6% vs. Oct 15, 2026
Days to cover
1.74
Short interest ÷ average daily volume
Average daily volume
1.62M
Shares, as reported by FINRA
Short interest by settlement date
Oct 31, 2024: 2,278,462 sharesNov 15, 2024: 2,591,194 sharesNov 29, 2024: 2,691,806 sharesDec 13, 2024: 3,210,787 sharesDec 31, 2024: 3,600,393 sharesJan 15, 2025: 3,559,325 sharesJan 31, 2025: 3,484,811 sharesFeb 14, 2025: 3,997,649 sharesFeb 28, 2025: 3,637,441 sharesMar 14, 2025: 3,218,733 sharesMar 31, 2025: 3,230,864 sharesApr 15, 2025: 3,514,906 sharesApr 30, 2025: 3,365,324 sharesMay 15, 2025: 3,513,951 sharesMay 30, 2025: 3,495,674 sharesJun 13, 2025: 3,407,735 sharesJun 30, 2025: 3,428,092 sharesJul 15, 2025: 3,118,762 sharesJul 31, 2025: 2,607,019 sharesAug 15, 2025: 3,057,522 sharesAug 29, 2025: 2,957,043 sharesSep 15, 2025: 3,035,339 sharesSep 30, 2025: 2,888,135 sharesOct 15, 2025: 2,678,106 sharesOct 31, 2025: 2,991,344 sharesNov 14, 2025: 2,448,181 sharesNov 28, 2025: 2,298,629 sharesDec 15, 2025: 2,256,427 sharesDec 31, 2025: 3,281,396 sharesJan 15, 2026: 3,086,503 sharesJan 30, 2026: 2,767,794 sharesFeb 13, 2026: 2,885,111 sharesFeb 27, 2026: 2,461,058 sharesMar 13, 2026: 2,554,186 sharesMar 31, 2026: 2,928,410 sharesApr 15, 2026: 2,933,303 sharesApr 30, 2026: 3,084,671 sharesMay 15, 2026: 2,823,532 sharesMay 29, 2026: 2,908,299 sharesJun 15, 2026: 3,253,513 sharesJun 30, 2026: 2,043,126 sharesJul 15, 2026: 2,786,071 sharesJul 31, 2026: 2,479,456 sharesAug 14, 2026: 2,718,056 sharesAug 31, 2026: 2,953,545 sharesSep 15, 2026: 3,217,345 sharesSep 30, 2026: 3,269,962 sharesOct 15, 2026: 2,620,423 sharesOct 30, 2026: 2,818,454 shares
Short interest in FORM by settlement date
Settlement dateShort interestChangeChange %Avg. daily volumeDays to cover
Oct 30, 20262.82M+198.0K+7.6%1.62M1.74
Oct 15, 20262.62M−649.5K−19.9%2.57M1.02
Sep 30, 20263.27M+52.6K+1.6%1.30M2.51
Sep 15, 20263.22M+263.8K+8.9%1.08M2.99
Aug 31, 20262.95M+235.5K+8.7%1.05M2.81
Aug 14, 20262.72M+238.6K+9.6%1.19M2.28
Jul 31, 20262.48M−306.6K−11.0%1.46M1.70
Jul 15, 20262.79M+742.9K+36.4%1.65M1.69
Jun 30, 20262.04M−1.21M−37.2%2.45M1.00
Jun 15, 20263.25M+345.2K+11.9%1.57M2.07
May 29, 20262.91M+84.8K+3.0%1.55M1.88
May 15, 20262.82M−261.1K−8.5%2.41M1.17
Apr 30, 20263.08M+151.4K+5.2%2.12M1.45
Apr 15, 20262.93M+4.89K+0.2%1.67M1.76
Mar 31, 20262.93M+374.2K+14.7%1.52M1.93
Mar 13, 20262.55M+93.1K+3.8%1.17M2.18
Feb 27, 20262.46M−424.1K−14.7%1.19M2.06
Feb 13, 20262.89M+117.3K+4.2%1.81M1.59
Jan 30, 20262.77M−318.7K−10.3%1.69M1.64
Jan 15, 20263.09M−194.9K−5.9%1.29M2.40
Dec 31, 20253.28M+1.02M+45.4%1.01M3.25
Dec 15, 20252.26M−42.2K−1.8%649.5K3.47
Nov 28, 20252.30M−149.6K−6.1%709.2K3.24
Nov 14, 20252.45M−543.2K−18.2%1.06M2.32
Oct 31, 20252.99M+313.2K+11.7%1.67M1.79
Oct 15, 20252.68M−210.0K−7.3%1.10M2.44
Sep 30, 20252.89M−147.2K−4.9%1.11M2.59
Sep 15, 20253.04M+78.3K+2.7%528.4K5.74
Aug 29, 20252.96M−100.5K−3.3%694.0K4.26
Aug 15, 20253.06M+450.5K+17.3%972.4K3.14
Jul 31, 20252.61M−511.7K−16.4%859.6K3.03
Jul 15, 20253.12M−309.3K−9.0%483.2K6.45
Jun 30, 20253.43M+20.4K+0.6%726.5K4.72
Jun 13, 20253.41M−87.9K−2.5%670.9K5.08
May 30, 20253.50M−18.3K−0.5%572.7K6.10
May 15, 20253.51M+148.6K+4.4%738.2K4.76
Apr 30, 20253.37M−149.6K−4.3%942.7K3.57
Apr 15, 20253.51M+284.0K+8.8%1.23M2.86
Mar 31, 20253.23M+12.1K+0.4%715.0K4.52
Mar 14, 20253.22M−418.7K−11.5%880.8K3.65
Feb 28, 20253.64M−360.2K−9.0%704.5K5.16
Feb 14, 20254.00M+512.8K+14.7%1.29M3.10
Jan 31, 20253.48M−74.5K−2.1%664.0K5.25
Jan 15, 20253.56M−41.1K−1.1%842.7K4.22
Dec 31, 20243.60M+389.6K+12.1%1.22M2.94
Dec 13, 20243.21M+519.0K+19.3%592.1K5.42
Nov 29, 20242.69M+100.6K+3.9%608.8K4.42
Nov 15, 20242.59M+312.7K+13.7%859.2K3.02
Oct 31, 20242.28M+464.0K+25.6%637.0K3.58

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 FORM by settlement date
Settlement dateSharesPriceValue
Oct 9, 2026353$137.13$48.4K
Oct 2, 202693$148.44$13.8K
Sep 29, 202629$130.97$3.80K
Sep 24, 2026153$131.26$20.1K
Sep 21, 2026108$118.38$12.8K
Sep 10, 202650$114.18$5.71K
Sep 8, 2026122$103.90$12.7K
Aug 31, 202651,559$101.70$5.24M
Aug 10, 202622$117.39$2.58K
Aug 7, 20261$115.21$115.21
Aug 3, 202649$106.20$5.20K
Jul 31, 20262$105.38$210.76
Jul 14, 2026192$110.30$21.2K
Jul 9, 202639$111.59$4.35K
Jul 8, 20268,814$106.05$934.7K
Jul 7, 202614$118.67$1.66K
Jul 6, 2026398$123.59$49.2K
Jul 2, 2026214$147.13$31.5K
Jun 30, 2026114,314$144.17$16.5M
Jun 29, 20261,109,186$130.74$145.0M
Jun 26, 202633$148.75$4.91K
Jun 22, 20261,862$149.55$278.5K
Jun 11, 202642$115.81$4.86K
Jun 2, 2026206$115.07$23.7K
May 22, 202621$128.00$2.69K
May 20, 2026379$117.20$44.4K
May 19, 20263,646$117.42$428.1K
May 12, 20261,548$151.40$234.4K
May 6, 20262,038$145.00$295.5K
May 4, 20263,706$137.37$509.1K

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 FORM by trade date
Trade dateShort volumeShort exemptOff-exchange volumeShort volume ratio
Nov 10, 2026242,31688441,66454.9%
Nov 9, 2026216,034106495,15443.6%
Nov 6, 2026323,6722,444657,41949.2%
Nov 5, 2026406,6159,1881,019,15039.9%
Nov 4, 2026262,3677,356922,39028.4%
Nov 3, 2026301,4837,775734,97641.0%
Nov 2, 2026293,6208,062751,32739.1%
Oct 30, 2026416,5929,1481,185,80135.1%
Oct 29, 2026562,76520,2141,563,88236.0%
Oct 28, 2026318,3860617,54951.6%
Oct 27, 2026253,49219476,27253.2%
Oct 26, 2026299,2330536,13655.8%
Oct 23, 2026200,56316,168439,57645.6%
Oct 22, 2026269,42914,390611,71944.0%
Oct 21, 2026385,789367567,96567.9%
Oct 20, 2026201,7860439,74845.9%
Oct 19, 2026379,285543736,09351.5%
Oct 16, 2026249,23720,196600,15241.5%
Oct 15, 2026350,76512,679769,99445.6%
Oct 14, 2026138,47910453,59030.5%
Oct 13, 2026149,3872599,44624.9%
Oct 12, 2026137,506218484,85828.4%
Oct 9, 2026107,8622327,43432.9%
Oct 8, 2026145,3311,147467,08731.1%
Oct 7, 2026106,621545403,73526.4%
Oct 6, 2026292,607960801,52236.5%
Oct 5, 2026569,599420816,26869.8%
Oct 2, 2026476,384183743,49464.1%
Oct 1, 2026227,4300467,59948.6%
Sep 30, 2026418,7681,682866,73848.3%

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 FORM
Week ofTierATS sharesATS tradesOther OTC sharesOther OTC tradesATS share
Oct 19, 2026T11,862,08246,6021,012,77421,54764.8%
Oct 12, 2026T12,075,99549,184931,85823,22469.0%
Oct 5, 2026T11,933,35252,0788,263,74121,34419.0%
Sep 28, 2026T12,373,35557,1761,471,48323,43761.7%
Sep 21, 2026T11,609,02244,948918,66017,76063.7%
Sep 14, 2026T11,779,35137,7111,032,47214,05563.3%
Sep 7, 2026T11,426,53132,511580,37612,69171.1%
Aug 31, 2026T11,770,16842,494684,70015,03372.1%
Aug 24, 2026T11,604,72436,804828,16213,80466.0%
Aug 17, 2026T11,427,87843,303869,54116,63562.2%
Aug 10, 2026T11,445,29641,834761,45515,85365.5%
Aug 3, 2026T12,065,29651,6801,053,70516,52666.2%