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PDF Solutions Inc

PDFS
Exchange
Nasdaq
Industry
Services-Prepackaged Software
SEC CIK
0001120914

In the last 90 days, PDF Solutions Inc insiders filed 0 open-market purchases and 1 sale; 284 institutions reported holding it in 13F filings for Q2 2026, worth $2.75B 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
3.51M
Shares, settlement Oct 30, 2026
Change
+199.6K
+6.0% vs. Oct 15, 2026
Days to cover
5.83
Short interest ÷ average daily volume
Average daily volume
602.3K
Shares, as reported by FINRA
Short interest by settlement date
Oct 31, 2024: 809,360 sharesNov 15, 2024: 752,632 sharesNov 29, 2024: 757,534 sharesDec 13, 2024: 701,638 sharesDec 31, 2024: 618,328 sharesJan 15, 2025: 629,836 sharesJan 31, 2025: 581,255 sharesFeb 14, 2025: 577,238 sharesFeb 28, 2025: 573,264 sharesMar 14, 2025: 655,682 sharesMar 31, 2025: 627,531 sharesApr 15, 2025: 645,897 sharesApr 30, 2025: 662,951 sharesMay 15, 2025: 705,958 sharesMay 30, 2025: 711,650 sharesJun 13, 2025: 813,238 sharesJun 30, 2025: 1,004,798 sharesJul 15, 2025: 1,226,903 sharesJul 31, 2025: 1,275,960 sharesAug 15, 2025: 1,389,016 sharesAug 29, 2025: 1,270,456 sharesSep 15, 2025: 1,316,974 sharesSep 30, 2025: 1,326,113 sharesOct 15, 2025: 1,371,611 sharesOct 31, 2025: 1,329,816 sharesNov 14, 2025: 1,361,406 sharesNov 28, 2025: 1,375,605 sharesDec 15, 2025: 1,554,868 sharesDec 31, 2025: 1,655,488 sharesJan 15, 2026: 1,790,181 sharesJan 30, 2026: 1,684,324 sharesFeb 13, 2026: 1,796,587 sharesFeb 27, 2026: 1,756,410 sharesMar 13, 2026: 1,786,751 sharesMar 31, 2026: 1,880,406 sharesApr 15, 2026: 1,713,003 sharesApr 30, 2026: 1,903,669 sharesMay 15, 2026: 1,755,337 sharesMay 29, 2026: 1,730,757 sharesJun 15, 2026: 2,220,874 sharesJun 30, 2026: 2,166,315 sharesJul 15, 2026: 2,583,493 sharesJul 31, 2026: 2,377,838 sharesAug 14, 2026: 2,435,684 sharesAug 31, 2026: 3,066,316 sharesSep 15, 2026: 3,248,816 sharesSep 30, 2026: 3,541,446 sharesOct 15, 2026: 3,310,252 sharesOct 30, 2026: 3,509,864 shares
Short interest in PDFS by settlement date
Settlement dateShort interestChangeChange %Avg. daily volumeDays to cover
Oct 30, 20263.51M+199.6K+6.0%602.3K5.83
Oct 15, 20263.31M−231.2K−6.5%586.4K5.65
Sep 30, 20263.54M+292.6K+9.0%609.4K5.81
Sep 15, 20263.25M+182.5K+6.0%568.8K5.71
Aug 31, 20263.07M+630.6K+25.9%694.8K4.41
Aug 14, 20262.44M+57.8K+2.4%495.9K4.91
Jul 31, 20262.38M−205.7K−8.0%512.5K4.64
Jul 15, 20262.58M+417.2K+19.3%662.9K3.90
Jun 30, 20262.17M−54.6K−2.5%826.6K2.62
Jun 15, 20262.22M+490.1K+28.3%862.2K2.58
May 29, 20261.73M−24.6K−1.4%663.5K2.61
May 15, 20261.76M−148.3K−7.8%1.22M1.43
Apr 30, 20261.90M+190.7K+11.1%575.4K3.31
Apr 15, 20261.71M−167.4K−8.9%341.2K5.02
Mar 31, 20261.88M+93.7K+5.2%368.0K5.11
Mar 13, 20261.79M+30.3K+1.7%287.2K6.22
Feb 27, 20261.76M−40.2K−2.2%290.5K6.05
Feb 13, 20261.80M+112.3K+6.7%351.0K5.12
Jan 30, 20261.68M−105.9K−5.9%290.7K5.79
Jan 15, 20261.79M+134.7K+8.1%302.9K5.91
Dec 31, 20251.66M+100.6K+6.5%223.1K7.42
Dec 15, 20251.55M+179.3K+13.0%294.6K5.28
Nov 28, 20251.38M+14.2K+1.0%291.9K4.71
Nov 14, 20251.36M+31.6K+2.4%326.2K4.17
Oct 31, 20251.33M−41.8K−3.1%205.1K6.48
Oct 15, 20251.37M+45.5K+3.4%240.8K5.70
Sep 30, 20251.33M+9.14K+0.7%426.7K3.11
Sep 15, 20251.32M+46.5K+3.7%223.3K5.90
Aug 29, 20251.27M−118.6K−8.5%285.5K4.45
Aug 15, 20251.39M+113.1K+8.9%369.7K3.76
Jul 31, 20251.28M+49.1K+4.0%228.6K5.58
Jul 15, 20251.23M+222.1K+22.1%300.8K4.08
Jun 30, 20251.00M+191.6K+23.6%282.0K3.56
Jun 13, 2025813.2K+101.6K+14.3%192.9K4.22
May 30, 2025711.6K+5.69K+0.8%193.3K3.68
May 15, 2025706.0K+43.0K+6.5%246.8K2.86
Apr 30, 2025663.0K+17.1K+2.6%200.0K3.31
Apr 15, 2025645.9K+18.4K+2.9%288.1K2.24
Mar 31, 2025627.5K−28.2K−4.3%256.6K2.45
Mar 14, 2025655.7K+82.4K+14.4%223.4K2.93
Feb 28, 2025573.3K−3.97K−0.7%350.8K1.63
Feb 14, 2025577.2K−4.02K−0.7%207.6K2.78
Jan 31, 2025581.3K−48.6K−7.7%250.9K2.32
Jan 15, 2025629.8K+11.5K+1.9%149.7K4.21
Dec 31, 2024618.3K−83.3K−11.9%181.5K3.41
Dec 13, 2024701.6K−55.9K−7.4%123.9K5.66
Nov 29, 2024757.5K+4.90K+0.7%139.8K5.42
Nov 15, 2024752.6K−56.7K−7.0%215.7K3.49
Oct 31, 2024809.4K+83.2K+11.5%114.9K7.05

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 PDFS by settlement date
Settlement dateSharesPriceValue
Oct 13, 202629$52.69$1.53K
Sep 30, 20261$49.77$49.77
Sep 9, 2026380$47.84$18.2K
Aug 28, 20261,104$46.15$50.9K
Aug 27, 20261,107$44.93$49.7K
Aug 26, 202694$44.28$4.16K
Aug 24, 20263,310$45.65$151.1K
Aug 14, 2026184$50.35$9.26K
Aug 11, 202651$47.63$2.43K
Aug 10, 2026206$49.45$10.2K
Jul 28, 202653$47.72$2.53K
Jul 20, 2026195$51.14$9.97K
Jul 17, 202627$51.93$1.40K
Jul 16, 202612$53.43$641.16
Jul 13, 2026699$55.52$38.8K
Jul 10, 202618$55.93$1.01K
Jul 8, 2026407$51.63$21.0K
Jul 6, 202618,805$59.18$1.11M
Jul 2, 20262,939$66.88$196.6K
Jun 29, 2026619$63.01$39.0K
Jun 25, 2026263$63.56$16.7K
Jun 23, 202629$64.95$1.88K
Jun 10, 2026452$58.74$26.6K
Jun 8, 2026894$51.45$46.0K
Jun 2, 2026639$51.28$32.8K
May 28, 20263,260$47.60$155.2K
May 27, 202610,294$48.95$503.9K
May 26, 202615,692$46.09$723.2K
May 18, 2026546$44.70$24.4K
May 7, 20261,996$48.09$96.0K

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 PDFS by trade date
Trade dateShort volumeShort exemptOff-exchange volumeShort volume ratio
Nov 12, 202665,39384143,22145.7%
Nov 11, 202671,4500113,69162.8%
Nov 10, 2026122,3620272,68144.9%
Nov 9, 2026188,92132272,12869.4%
Nov 6, 2026342,3359,117466,86073.3%
Nov 5, 2026216,0526,969416,87051.8%
Nov 4, 2026183,3480333,64855.0%
Nov 3, 2026186,7630262,44671.2%
Nov 2, 2026120,8229,633242,19849.9%
Oct 30, 2026286,4991,846394,60772.6%
Oct 29, 2026169,7820225,83475.2%
Oct 28, 2026110,0090177,10862.1%
Oct 27, 2026131,0840178,59073.4%
Oct 26, 2026108,7540151,76371.7%
Oct 23, 202696,4682,110170,74056.5%
Oct 22, 2026171,8572,315273,16562.9%
Oct 21, 2026172,9860210,45682.2%
Oct 20, 2026148,631228194,33376.5%
Oct 19, 2026149,3860193,22277.3%
Oct 16, 2026144,3500171,02384.4%
Oct 15, 2026221,1982,732319,41669.3%
Oct 14, 202688,1022,158207,68442.4%
Oct 13, 2026193,0232,233413,95946.6%
Oct 12, 2026191,51536248,35077.1%
Oct 9, 2026152,7790191,10879.9%
Oct 8, 2026155,5420193,02680.6%
Oct 7, 2026100,1520122,44681.8%
Oct 6, 2026230,1460256,50289.7%
Oct 5, 2026164,7720196,47083.9%
Oct 2, 2026127,1055152,43483.4%

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 PDFS
Week ofTierATS sharesATS tradesOther OTC sharesOther OTC tradesATS share
Oct 5, 2026T2712,36224,119327,1375,53868.5%
Sep 28, 2026T2786,41426,529410,4405,70965.7%
Sep 21, 2026T2760,48130,138230,5204,99076.7%
Sep 14, 2026T2839,10427,735662,9575,40055.9%
Sep 7, 2026T2620,27026,138280,2474,86068.9%
Aug 31, 2026T2851,70727,850322,9465,94372.5%
Aug 24, 2026T21,530,40429,499355,9394,93681.1%
Aug 17, 2026T2777,70722,787373,0925,40767.6%
Aug 10, 2026T2625,41323,691375,2185,69662.5%
Aug 3, 2026T2741,02527,463244,3094,66675.2%
Jul 27, 2026T2858,78325,873407,4275,10067.8%
Jul 20, 2026T2522,39818,745279,8894,27865.1%