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Livermore
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Builders FirstSource, Inc.

BLDR
Exchange
NYSE
Industry
Retail-Lumber & Other Building Materials Dealers
SEC CIK
0001316835

No open-market purchases or sales by Builders FirstSource, Inc. insiders were filed in the last 90 days; 674 institutions reported holding it in 13F filings for Q2 2026, worth $9.63B in total; 3 superinvestors hold it, including D1 Capital Partners and Semper Augustus.

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
8.85M
Shares, settlement Oct 30, 2026
Change
−1.09M
−11.0% vs. Oct 15, 2026
Days to cover
3.11
Short interest ÷ average daily volume
Average daily volume
2.84M
Shares, as reported by FINRA
Short interest by settlement date
Oct 31, 2024: 2,479,074 sharesNov 15, 2024: 2,278,365 sharesNov 29, 2024: 2,111,707 sharesDec 13, 2024: 2,592,138 sharesDec 31, 2024: 3,157,926 sharesJan 15, 2025: 3,485,001 sharesJan 31, 2025: 4,026,604 sharesFeb 14, 2025: 3,449,462 sharesFeb 28, 2025: 4,152,185 sharesMar 14, 2025: 4,926,975 sharesMar 31, 2025: 4,204,518 sharesApr 15, 2025: 3,898,412 sharesApr 30, 2025: 4,311,088 sharesMay 15, 2025: 4,881,319 sharesMay 30, 2025: 6,103,244 sharesJun 13, 2025: 6,619,721 sharesJun 30, 2025: 6,172,635 sharesJul 15, 2025: 6,853,730 sharesJul 31, 2025: 6,028,800 sharesAug 15, 2025: 6,497,410 sharesAug 29, 2025: 7,112,672 sharesSep 15, 2025: 8,022,488 sharesSep 30, 2025: 6,856,227 sharesOct 15, 2025: 6,275,268 sharesOct 31, 2025: 5,884,781 sharesNov 14, 2025: 5,573,309 sharesNov 28, 2025: 5,122,241 sharesDec 15, 2025: 4,578,394 sharesDec 31, 2025: 4,765,888 sharesJan 15, 2026: 4,753,876 sharesJan 30, 2026: 4,508,345 sharesFeb 13, 2026: 4,698,707 sharesFeb 27, 2026: 5,576,445 sharesMar 13, 2026: 6,603,493 sharesMar 31, 2026: 7,084,828 sharesApr 15, 2026: 7,230,744 sharesApr 30, 2026: 8,059,726 sharesMay 15, 2026: 8,682,445 sharesMay 29, 2026: 8,797,863 sharesJun 15, 2026: 7,936,719 sharesJun 30, 2026: 7,603,336 sharesJul 15, 2026: 7,200,190 sharesJul 31, 2026: 8,013,450 sharesAug 14, 2026: 7,264,682 sharesAug 31, 2026: 7,829,223 sharesSep 15, 2026: 8,907,075 sharesSep 30, 2026: 9,165,569 sharesOct 15, 2026: 9,939,716 sharesOct 30, 2026: 8,846,154 shares
Short interest in BLDR by settlement date
Settlement dateShort interestChangeChange %Avg. daily volumeDays to cover
Oct 30, 20268.85M−1.09M−11.0%2.84M3.11
Oct 15, 20269.94M+774.1K+8.5%2.55M3.89
Sep 30, 20269.17M+258.5K+2.9%4.72M1.94
Sep 15, 20268.91M+1.08M+13.8%2.64M3.37
Aug 31, 20267.83M+564.5K+7.8%1.79M4.38
Aug 14, 20267.26M−748.8K−9.3%1.94M3.75
Jul 31, 20268.01M+813.3K+11.3%2.63M3.05
Jul 15, 20267.20M−403.1K−5.3%1.99M3.61
Jun 30, 20267.60M−333.4K−4.2%2.65M2.87
Jun 15, 20267.94M−861.1K−9.8%2.22M3.57
May 29, 20268.80M+115.4K+1.3%3.39M2.59
May 15, 20268.68M+622.7K+7.7%3.04M2.85
Apr 30, 20268.06M+829.0K+11.5%2.57M3.14
Apr 15, 20267.23M+145.9K+2.1%1.93M3.75
Mar 31, 20267.08M+481.3K+7.3%2.16M3.28
Mar 13, 20266.60M+1.03M+18.4%3.01M2.19
Feb 27, 20265.58M+877.7K+18.7%2.12M2.63
Feb 13, 20264.70M+190.4K+4.2%2.71M1.73
Jan 30, 20264.51M−245.5K−5.2%1.86M2.42
Jan 15, 20264.75M−12.0K−0.3%2.24M2.12
Dec 31, 20254.77M+187.5K+4.1%1.49M3.21
Dec 15, 20254.58M−543.8K−10.6%1.79M2.55
Nov 28, 20255.12M−451.1K−8.1%2.60M1.97
Nov 14, 20255.57M−311.5K−5.3%2.53M2.20
Oct 31, 20255.88M−390.5K−6.2%1.80M3.27
Oct 15, 20256.28M−581.0K−8.5%1.69M3.71
Sep 30, 20256.86M−1.17M−14.5%2.19M3.14
Sep 15, 20258.02M+909.8K+12.8%1.71M4.69
Aug 29, 20257.11M+615.3K+9.5%1.98M3.58
Aug 15, 20256.50M+468.6K+7.8%2.37M2.74
Jul 31, 20256.03M−824.9K−12.0%2.00M3.01
Jul 15, 20256.85M+681.1K+11.0%2.59M2.64
Jun 30, 20256.17M−447.1K−6.8%2.66M2.32
Jun 13, 20256.62M+516.5K+8.5%1.86M3.56
May 30, 20256.10M+1.22M+25.0%1.99M3.07
May 15, 20254.88M+570.2K+13.2%2.55M1.91
Apr 30, 20254.31M+412.7K+10.6%1.40M3.08
Apr 15, 20253.90M−306.1K−7.3%1.95M2.00
Mar 31, 20254.20M−722.5K−14.7%1.52M2.77
Mar 14, 20254.93M+774.8K+18.7%1.80M2.74
Feb 28, 20254.15M+702.7K+20.4%2.33M1.79
Feb 14, 20253.45M−577.1K−14.3%1.38M2.50
Jan 31, 20254.03M+541.6K+15.5%1.48M2.72
Jan 15, 20253.49M+327.1K+10.4%1.73M2.02
Dec 31, 20243.16M+565.8K+21.8%1.76M1.80
Dec 13, 20242.59M+480.4K+22.8%1.06M2.46
Nov 29, 20242.11M−166.7K−7.3%1.13M1.87
Nov 15, 20242.28M−200.7K−8.1%1.61M1.42
Oct 31, 20242.48M−264.9K−9.7%1.12M2.21

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 BLDR by settlement date
Settlement dateSharesPriceValue
Oct 9, 202631$53.81$1.67K
Oct 1, 20267$57.01$399.07
Sep 30, 202614,100$57.53$811.2K
Sep 23, 2026252$60.87$15.3K
Sep 22, 20262,927$58.52$171.3K
Sep 21, 2026410,946$58.12$23.9M
Sep 17, 20264,461$59.65$266.1K
Sep 4, 2026154$64.18$9.88K
Aug 20, 202618$72.55$1.31K
Aug 17, 202650$72.51$3.63K
Aug 14, 202634,528$73.56$2.54M
Aug 7, 20264,395$72.51$318.7K
Aug 6, 2026834$75.86$63.3K
Aug 3, 202679$66.44$5.25K
Jul 31, 2026300$66.01$19.8K
Jul 24, 2026200$70.55$14.1K
Jul 23, 2026200$71.03$14.2K
Jul 22, 2026200$69.74$13.9K
Jul 15, 202611,023$75.16$828.5K
Jul 9, 2026240$74.20$17.8K
Jul 8, 2026189$78.42$14.8K
Jul 7, 202611,738$82.33$966.4K
Jul 6, 202632,784$84.69$2.78M
Jun 30, 202624,796$90.51$2.24M
Jun 29, 2026561$89.14$50.0K
Jun 15, 2026151$77.77$11.7K
Jun 10, 2026145$77.54$11.2K
Jun 9, 2026311$73.12$22.7K
Jun 5, 20261,538$74.98$115.3K
Jun 4, 202618$74.26$1.34K

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 BLDR by trade date
Trade dateShort volumeShort exemptOff-exchange volumeShort volume ratio
Nov 10, 2026401,9473,450793,92050.6%
Nov 9, 2026297,25901,106,04926.9%
Nov 6, 2026372,4201,503921,36740.4%
Nov 5, 2026404,6681,880989,99840.9%
Nov 4, 2026935,3592,7161,785,88852.4%
Nov 3, 2026612,0922,1371,109,97255.1%
Nov 2, 2026710,619381,530,54346.4%
Oct 30, 2026856,4275452,046,11841.9%
Oct 29, 2026808,6987702,596,39131.1%
Oct 28, 2026541,41473977,74155.4%
Oct 27, 2026485,758512848,45157.3%
Oct 26, 2026465,256341,040,33444.7%
Oct 23, 2026477,720391941,67650.7%
Oct 22, 2026457,93401,203,86138.0%
Oct 21, 2026318,27925,627672,07747.4%
Oct 20, 2026275,89674809,77934.1%
Oct 19, 2026368,5370957,24138.5%
Oct 16, 2026450,6912,6921,167,14938.6%
Oct 15, 2026388,49802,274,25817.1%
Oct 14, 2026434,77001,521,14128.6%
Oct 13, 2026148,7060916,20916.2%
Oct 12, 2026279,0200840,08033.2%
Oct 9, 2026269,2413902,03229.8%
Oct 8, 2026356,017441,065,08433.4%
Oct 7, 2026519,43519,5531,078,99148.1%
Oct 6, 2026357,26629978,55736.5%
Oct 5, 2026488,5721,900905,69653.9%
Oct 2, 2026315,185839823,07838.3%
Oct 1, 2026446,624108988,47245.2%
Sep 30, 2026455,22392999,53245.5%

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 BLDR
Week ofTierATS sharesATS tradesOther OTC sharesOther OTC tradesATS share
Oct 19, 2026T13,390,67367,1961,600,28416,55067.9%
Oct 12, 2026T15,251,40072,5481,639,55319,01776.2%
Oct 5, 2026T13,344,99363,6772,004,03116,26462.5%
Sep 28, 2026T13,244,18767,9221,497,54716,71968.4%
Sep 21, 2026T13,748,33563,2032,197,09616,69063.0%
Sep 14, 2026T14,704,63681,07011,455,83520,31229.1%
Sep 7, 2026T13,340,98469,0491,668,20017,58666.7%
Aug 31, 2026T13,553,98669,7922,524,52520,47858.5%
Aug 24, 2026T12,608,93053,7731,540,50915,63662.9%
Aug 17, 2026T12,388,70459,5611,112,51117,44268.2%
Aug 10, 2026T12,417,69261,7131,161,10516,80667.6%
Aug 3, 2026T13,201,04874,8661,430,92617,30469.1%