Core Laboratories (CLB)
Core Laboratories on one page: short interest, daily short volume, fails to deliver, large holders, 13F holders, earnings dates and insider trades. Listed on NYSE, classified by the SEC as oil & gas field services, nec.
4.9M
Short interest
settlement 2026-09-30
6.8
Days to cover
-3.4 days vs prior
27.2%
Short share of volume
2026-10-23
752
Fails to deliver
settlement 2026-09-29
Wed 3 Feb
Next earnings
estimated date
$54K
Insider flow, 90 days
1 buys, 0 sells
As of 2026-10-23.
Short interest
FINRA, twice a month. The newest 48 settlements in the table, 48 in the chart. JSONAs of 30 September 2026, short interest in CLB is 4,868,011 shares, up 772,334 shares over the last month. Over the last 48 readings it ranged from 3,963,908 shares (28 November 2025) to 8,315,209 shares (29 August 2025). At the reported average volume of 715K shares a day that is 6.8 days to cover.
Embed this chart.The embed keeps its attribution line.
<iframe src="https://xoomar.com/embed/stocks/clb" width="100%" height="440" style="border:0;max-width:100%" loading="lazy" title="XOOMAR chart"></iframe>
| Settlement | Shares short | Change | Avg daily volume | Days to cover |
|---|---|---|---|---|
| 2026-09-30 | 4,868,011 | +11.1% | 714,904 | 6.81 |
| 2026-09-15 | 4,382,706 | +7.0% | 427,968 | 10.24 |
| 2026-08-31 | 4,095,677 | -3.8% | 427,005 | 9.59 |
| 2026-08-14 | 4,255,516 | +1.5% | 587,406 | 7.24 |
| 2026-07-31 | 4,194,215 | +4.2% | 835,012 | 5.02 |
| 2026-07-15 | 4,023,689 | -32.6% | 1,615,519 | 2.49 |
| 2026-06-30 | 5,971,336 | +7.8% | 1,032,322 | 5.78 |
| 2026-06-15 | 5,536,608 | -3.0% | 577,948 | 9.58 |
| 2026-05-29 | 5,710,295 | +12.7% | 509,181 | 11.21 |
| 2026-05-15 | 5,066,718 | +2.6% | 551,798 | 9.18 |
| 2026-04-30 | 4,940,102 | +15.9% | 467,129 | 10.58 |
| 2026-04-15 | 4,261,903 | -7.4% | 303,154 | 14.06 |
| 2026-03-31 | 4,601,654 | +3.2% | 447,403 | 10.29 |
| 2026-03-13 | 4,460,149 | +3.1% | 378,488 | 11.78 |
| 2026-02-27 | 4,325,141 | +4.1% | 430,760 | 10.04 |
| 2026-02-13 | 4,154,682 | -2.0% | 449,494 | 9.24 |
| 2026-01-30 | 4,240,773 | +5.2% | 333,536 | 12.71 |
| 2026-01-15 | 4,030,175 | -10.6% | 373,783 | 10.78 |
| 2025-12-31 | 4,508,462 | +5.5% | 349,239 | 12.91 |
| 2025-12-15 | 4,274,089 | +7.8% | 350,913 | 12.18 |
| 2025-11-28 | 3,963,908 | -16.5% | 454,188 | 8.73 |
| 2025-11-14 | 4,744,802 | -14.0% | 535,640 | 8.86 |
| 2025-10-31 | 5,515,889 | -14.0% | 746,533 | 7.39 |
| 2025-10-15 | 6,412,826 | -6.8% | 602,346 | 10.65 |
| 2025-09-30 | 6,883,429 | -14.3% | 567,598 | 12.13 |
| 2025-09-15 | 8,034,177 | -3.4% | 619,820 | 12.96 |
| 2025-08-29 | 8,315,209 | +4.7% | 397,166 | 20.94 |
| 2025-08-15 | 7,940,775 | +5.5% | 518,995 | 15.30 |
| 2025-07-31 | 7,524,653 | -2.3% | 532,224 | 14.14 |
| 2025-07-15 | 7,697,800 | +3.7% | 445,596 | 17.28 |
| 2025-06-30 | 7,425,671 | -5.5% | 745,020 | 9.97 |
| 2025-06-13 | 7,857,828 | +4.2% | 336,526 | 23.35 |
| 2025-05-30 | 7,542,645 | -3.1% | 355,270 | 21.23 |
| 2025-05-15 | 7,784,529 | +1.6% | 553,002 | 14.08 |
| 2025-04-30 | 7,661,131 | +15.8% | 666,580 | 11.49 |
| 2025-04-15 | 6,613,433 | +0.1% | 666,684 | 9.92 |
| 2025-03-31 | 6,605,780 | +1.1% | 325,118 | 20.32 |
| 2025-03-14 | 6,532,968 | +1.0% | 454,269 | 14.38 |
| 2025-02-28 | 6,466,738 | +6.5% | 306,289 | 21.11 |
| 2025-02-14 | 6,073,941 | -1.3% | 344,513 | 17.63 |
| 2025-01-31 | 6,154,001 | -0.7% | 327,494 | 18.79 |
| 2025-01-15 | 6,195,902 | -1.5% | 265,635 | 23.32 |
| 2024-12-31 | 6,289,811 | -6.6% | 378,099 | 16.64 |
| 2024-12-13 | 6,733,694 | +3.6% | 246,389 | 27.33 |
| 2024-11-29 | 6,501,450 | -5.0% | 234,726 | 27.70 |
| 2024-11-15 | 6,845,356 | -1.5% | 319,121 | 21.45 |
| 2024-10-31 | 6,951,139 | -0.5% | 355,763 | 19.54 |
| 2024-10-15 | 6,985,214 | +1.8% | 296,165 | 23.59 |
Daily short volume
FINRA Reg SHO, the last 30 sessions. JSONAs of 23 October 2026, the short share of CLB volume is 27.2%, down 13.2 points over the last five sessions. Over the last 30 readings it ranged from 22.6% (5 October 2026) to 84.3% (17 September 2026). The latest reading sits at the bottom of that range. The latest reading is 21.2 points below the 30-session average of 48.4%, on 445K shares reported.
| Date | Short volume | Total volume | Short share | Exempt |
|---|---|---|---|---|
| 2026-10-23 | 121K | 445K | 27.2% | 586 |
| 2026-10-22 | 268K | 440K | 61.0% | 0 |
| 2026-10-21 | 93K | 193K | 48.2% | 308 |
| 2026-10-20 | 64K | 139K | 46.4% | 0 |
| 2026-10-19 | 64K | 137K | 46.7% | 1 |
| 2026-10-16 | 57K | 140K | 40.4% | 12 |
| 2026-10-15 | 94K | 308K | 30.4% | 0 |
| 2026-10-14 | 100K | 207K | 48.4% | 111 |
| 2026-10-13 | 153K | 296K | 51.7% | 1,799 |
| 2026-10-12 | 79K | 151K | 52.0% | 0 |
| 2026-10-09 | 66K | 123K | 53.5% | 266 |
| 2026-10-08 | 64K | 106K | 60.2% | 0 |
| 2026-10-07 | 123K | 249K | 49.3% | 0 |
| 2026-10-06 | 109K | 194K | 56.5% | 0 |
| 2026-10-05 | 95K | 421K | 22.6% | 0 |
| 2026-10-02 | 109K | 222K | 48.9% | 0 |
| 2026-10-01 | 93K | 261K | 35.5% | 0 |
| 2026-09-30 | 108K | 262K | 41.3% | 8,621 |
| 2026-09-29 | 105K | 332K | 31.7% | 0 |
| 2026-09-28 | 80K | 200K | 39.9% | 0 |
| 2026-09-25 | 110K | 313K | 35.1% | 0 |
| 2026-09-24 | 97K | 197K | 49.2% | 0 |
| 2026-09-23 | 84K | 259K | 32.3% | 0 |
| 2026-09-22 | 121K | 281K | 42.9% | 0 |
| 2026-09-21 | 94K | 243K | 38.7% | 0 |
| 2026-09-18 | 160K | 210K | 75.8% | 0 |
| 2026-09-17 | 230K | 273K | 84.3% | 0 |
| 2026-09-16 | 131K | 178K | 73.7% | 0 |
| 2026-09-15 | 109K | 154K | 70.9% | 0 |
| 2026-09-14 | 87K | 149K | 58.5% | 0 |
Fails to deliver
SEC, the last 30 settlement dates with a fail. JSONAs of 29 September 2026, the fails-to-deliver balance in CLB is 752 shares, up 692 shares over the last settlement date. Over the last 30 readings it ranged from 1 share (23 July 2026) to 7,907 shares (2 July 2026). The latest reading sits at the bottom of that range.
| Settlement | Shares failed | Price | Value |
|---|---|---|---|
| 2026-09-29 | 752 | $10.03 | $8K |
| 2026-09-23 | 60 | $10.94 | $656 |
| 2026-09-18 | 63 | $11.40 | $718 |
| 2026-09-16 | 444 | $12.26 | $5K |
| 2026-09-14 | 86 | $12.50 | $1K |
| 2026-09-08 | 42 | $12.54 | $527 |
| 2026-09-04 | 3,085 | $12.53 | $39K |
| 2026-09-02 | 1,730 | $12.39 | $21K |
| 2026-08-31 | 859 | $12.36 | $11K |
| 2026-08-27 | 2 | $11.99 | $24 |
| 2026-08-26 | 5,195 | $12.06 | $63K |
| 2026-08-25 | 6,199 | $12.05 | $75K |
| 2026-08-21 | 2,859 | $12.29 | $35K |
| 2026-08-20 | 821 | $12.65 | $10K |
| 2026-08-19 | 1,926 | $12.52 | $24K |
| 2026-08-17 | 3,406 | $12.45 | $42K |
| 2026-08-14 | 1,856 | $12.39 | $23K |
| 2026-08-11 | 587 | $12.22 | $7K |
| 2026-08-06 | 16 | $10.95 | $175 |
| 2026-08-04 | 6,396 | $10.71 | $69K |
| 2026-08-03 | 6,599 | $10.64 | $70K |
| 2026-07-31 | 611 | $10.35 | $6K |
| 2026-07-23 | 1 | $11.96 | $12 |
| 2026-07-08 | 3,031 | $10.89 | $33K |
| 2026-07-02 | 7,907 | $11.57 | $91K |
| 2026-07-01 | 184 | $11.65 | $2K |
| 2026-06-26 | 320 | $10.92 | $3K |
| 2026-06-24 | 412 | $11.64 | $5K |
| 2026-06-12 | 1,732 | $13.25 | $23K |
| 2026-06-09 | 764 | $13.43 | $10K |
Insider trades
SEC Form 4, newest first. JSONInsiders at CLB reported 1 open-market buy worth $54K in the last 90 days and no open-market sells. Latest filing: Teo Sow Hang (CAO & Treasurer) on 2026-10-01.
| Date | Insider | Title | Type | Shares | Price | Value | Owned after |
|---|---|---|---|---|---|---|---|
| 2026-10-01 | Teo Sow Hang | CAO & Treasurer | Exercise or conversion | 250 | $0.00 | $0 | 9K |
| 2026-10-01 | Teo Sow Hang | CAO & Treasurer | Tax withholding | 99 | $9.76 | $966 | 9K |
| 2026-10-01 | Tattoli Mark Damian | SVP, Gen Counsel & Secretary | Exercise or conversion | 700 | $0.00 | $0 | 28K |
| 2026-10-01 | Tattoli Mark Damian | SVP, Gen Counsel & Secretary | Tax withholding | 276 | $9.76 | $3K | 28K |
| 2026-08-01 | Teo Sow Hang | CAO & Treasurer | Exercise or conversion | 200 | $0.00 | $0 | 9K |
| 2026-08-01 | Teo Sow Hang | CAO & Treasurer | Tax withholding | 90 | $10.64 | $958 | 9K |
| 2026-08-01 | Teo Sow Hang | CAO & Treasurer | Exercise or conversion | 240 | $0.00 | $0 | 9K |
| 2026-08-01 | Teo Sow Hang | CAO & Treasurer | Tax withholding | 108 | $10.64 | $1K | 9K |
| 2026-08-01 | Tattoli Mark Damian | SVP, Gen Counsel & Secretary | Exercise or conversion | 250 | $0.00 | $0 | 28K |
| 2026-08-01 | Tattoli Mark Damian | SVP, Gen Counsel & Secretary | Tax withholding | 99 | $10.64 | $1K | 28K |
| 2026-07-31 | Bruno Lawrence | Chairman and CEO | Buy | 5K | $10.78 | $54K | 262K |
| 2026-05-01 | Tattoli Mark Damian | SVP, Gen Counsel & Secretary | Exercise or conversion | 250 | $0.00 | $0 | 28K |
| 2026-05-01 | Tattoli Mark Damian | SVP, Gen Counsel & Secretary | Tax withholding | 97 | $14.07 | $1K | 28K |
| 2026-04-01 | Klingensmith Harvey Robert | Director | Exercise or conversion | 8K | $0.00 | $0 | 50K |
| 2026-04-01 | Temeng Kwaku | Director | Exercise or conversion | 8K | $0.00 | $0 | 34K |
| 2026-04-01 | MARTINOVICH ROBERT F | Director | Exercise or conversion | 8K | $0.00 | $0 | 8K |
| 2026-04-01 | Carnes Martha Z. | Director | Exercise or conversion | 8K | $0.00 | $0 | 54K |
| 2026-04-01 | ANASTASIO CURT | Director | Exercise or conversion | 8K | $0.00 | $0 | 24K |
| 2026-04-01 | Murray Katherine | Director | Exercise or conversion | 8K | $0.00 | $0 | 29K |
| 2025-12-31 | Tattoli Mark Damian | SVP, Gen Counsel & Secretary | Exercise or conversion | 25K | $0.00 | $0 | 42K |
| 2025-12-31 | Tattoli Mark Damian | SVP, Gen Counsel & Secretary | Tax withholding | 14K | $16.03 | $229K | 27K |
| 2025-12-31 | Gresham Gwendolyn | SVP | Exercise or conversion | 25K | $0.00 | $0 | 53K |
| 2025-12-31 | Gresham Gwendolyn | SVP | Tax withholding | 19K | $16.03 | $309K | 33K |
| 2025-12-31 | Hill Christopher Scott | SVP & CFO | Exercise or conversion | 61K | $0.00 | $0 | 142K |
| 2025-12-31 | Hill Christopher Scott | SVP & CFO | Tax withholding | 32K | $16.03 | $515K | 110K |
| 2025-12-31 | Bruno Lawrence | Chairman and CEO | Exercise or conversion | 181K | $0.00 | $0 | 370K |
| 2025-12-31 | Bruno Lawrence | Chairman and CEO | Tax withholding | 113K | $16.03 | $1.8M | 257K |
| 2025-12-01 | Teo Sow Hang | CAO & Treasurer | Exercise or conversion | 864 | $0.00 | $0 | 9K |
| 2025-12-01 | Teo Sow Hang | CAO & Treasurer | Tax withholding | 340 | $15.39 | $5K | 8K |
| 2025-10-01 | Tattoli Mark Damian | SVP, Gen Counsel & Secretary | Exercise or conversion | 700 | $0.00 | $0 | 17K |
| 2025-10-01 | Tattoli Mark Damian | SVP, Gen Counsel & Secretary | Tax withholding | 276 | $12.58 | $3K | 17K |
| 2025-10-01 | Teo Sow Hang | CAO & Treasurer | Exercise or conversion | 250 | $0.00 | $0 | 8K |
| 2025-10-01 | Teo Sow Hang | CAO & Treasurer | Tax withholding | 99 | $12.58 | $1K | 8K |
| 2025-08-01 | Tattoli Mark Damian | SVP, Gen Counsel & Secretary | Exercise or conversion | 250 | $0.00 | $0 | 16K |
| 2025-08-01 | Tattoli Mark Damian | SVP, Gen Counsel & Secretary | Tax withholding | 99 | $10.53 | $1K | 16K |
| 2025-08-01 | Teo Sow Hang | CAO & Treasurer | Exercise or conversion | 240 | $0.00 | $0 | 8K |
| 2025-08-01 | Teo Sow Hang | CAO & Treasurer | Tax withholding | 108 | $10.53 | $1K | 8K |
| 2025-08-01 | Teo Sow Hang | CAO & Treasurer | Exercise or conversion | 200 | $0.00 | $0 | 8K |
| 2025-08-01 | Teo Sow Hang | CAO & Treasurer | Tax withholding | 90 | $10.53 | $948 | 8K |
| 2025-05-01 | Tattoli Mark Damian | SVP, Gen Counsel & Secretary | Exercise or conversion | 250 | $0.00 | $0 | 16K |
| 2025-05-01 | Tattoli Mark Damian | SVP, Gen Counsel & Secretary | Tax withholding | 79 | $11.68 | $923 | 16K |
| 2025-05-01 | Tattoli Mark Damian | SVP, Gen Counsel & Secretary | Exercise or conversion | 200 | $0.00 | $0 | 16K |
| 2025-05-01 | Tattoli Mark Damian | SVP, Gen Counsel & Secretary | Tax withholding | 99 | $11.68 | $1K | 16K |
| 2025-05-01 | Teo Sow Hang | CAO & Treasurer | Tax withholding | 79 | $11.68 | $923 | 8K |
| 2025-05-01 | Teo Sow Hang | CAO & Treasurer | Exercise or conversion | 175 | $0.00 | $0 | 8K |
| 2025-04-01 | Straughen Michael | Director | Tax withholding | 5K | $14.98 | $69K | 25K |
| 2025-04-01 | Straughen Michael | Director | Exercise or conversion | 9K | $0.00 | $0 | 29K |
| 2025-04-01 | ANASTASIO CURT | Director | Exercise or conversion | 9K | $0.00 | $0 | 16K |
| 2025-04-01 | Carnes Martha Z. | Director | Exercise or conversion | 9K | $0.00 | $0 | 46K |
| 2025-04-01 | Klingensmith Harvey Robert | Director | Exercise or conversion | 9K | $0.00 | $0 | 42K |
| 2025-04-01 | Murray Katherine | Director | Exercise or conversion | 9K | $0.00 | $0 | 21K |
| 2025-04-01 | Temeng Kwaku | Director | Exercise or conversion | 9K | $0.00 | $0 | 26K |
| 2024-12-31 | Tattoli Mark Damian | SVP, Gen Counsel & Secretary | Tax withholding | 5K | $17.31 | $87K | 16K |
| 2024-12-31 | Tattoli Mark Damian | SVP, Gen Counsel & Secretary | Exercise or conversion | 10K | $0.00 | $0 | 21K |
| 2024-12-31 | Gresham Gwendolyn | SVP | Tax withholding | 6K | $17.31 | $104K | 28K |
| 2024-12-31 | Gresham Gwendolyn | SVP | Exercise or conversion | 10K | $0.00 | $0 | 34K |
| 2024-12-31 | Hill Christopher Scott | SVP & CFO | Exercise or conversion | 24K | $0.00 | $0 | 96K |
| 2024-12-31 | Hill Christopher Scott | SVP & CFO | Tax withholding | 15K | $17.31 | $255K | 81K |
| 2024-12-31 | Bruno Lawrence | Chairman and CEO | Tax withholding | 43K | $17.31 | $751K | 189K |
| 2024-12-31 | Bruno Lawrence | Chairman and CEO | Exercise or conversion | 70K | $0.00 | $0 | 233K |
| 2024-12-01 | Teo Sow Hang | CAO & Treasurer | Exercise or conversion | 576 | $0.00 | $0 | 8K |
| 2024-12-01 | Teo Sow Hang | CAO & Treasurer | Tax withholding | 227 | $20.42 | $5K | 7K |
| 2024-10-01 | Tattoli Mark Damian | SVP, Gen Counsel & Secretary | Tax withholding | 276 | $19.21 | $5K | 11K |
| 2024-10-01 | Tattoli Mark Damian | SVP, Gen Counsel & Secretary | Exercise or conversion | 700 | $0.00 | $0 | 12K |
| 2024-10-01 | Teo Sow Hang | CAO & Treasurer | Exercise or conversion | 250 | $0.00 | $0 | 7K |
| 2024-10-01 | Teo Sow Hang | CAO & Treasurer | Tax withholding | 99 | $19.21 | $2K | 7K |
| 2024-08-01 | Teo Sow Hang | CAO & Treasurer | Exercise or conversion | 200 | $0.00 | $0 | 7K |
| 2024-08-01 | Teo Sow Hang | CAO & Treasurer | Tax withholding | 35 | $23.24 | $813 | 7K |
| 2024-08-01 | Teo Sow Hang | CAO & Treasurer | Exercise or conversion | 240 | $0.00 | $0 | 7K |
| 2024-08-01 | Teo Sow Hang | CAO & Treasurer | Exercise or conversion | 80 | $0.00 | $0 | 7K |
| 2024-08-01 | Teo Sow Hang | CAO & Treasurer | Tax withholding | 90 | $23.24 | $2K | 7K |
| 2024-08-01 | Teo Sow Hang | CAO & Treasurer | Tax withholding | 93 | $23.24 | $2K | 7K |
| 2024-08-01 | Tattoli Mark Damian | SVP, Gen Counsel & Secretary | Exercise or conversion | 120 | $0.00 | $0 | 11K |
| 2024-08-01 | Tattoli Mark Damian | SVP, Gen Counsel & Secretary | Exercise or conversion | 250 | $0.00 | $0 | 11K |
| 2024-08-01 | Tattoli Mark Damian | SVP, Gen Counsel & Secretary | Tax withholding | 99 | $23.24 | $2K | 11K |
| 2024-08-01 | Tattoli Mark Damian | SVP, Gen Counsel & Secretary | Tax withholding | 48 | $23.24 | $1K | 11K |
| 2024-05-01 | Tattoli Mark Damian | SVP, Gen Counsel & Secretary | Exercise or conversion | 200 | $0.00 | $0 | 11K |
| 2024-05-01 | Tattoli Mark Damian | SVP, Gen Counsel & Secretary | Tax withholding | 79 | $15.71 | $1K | 10K |
| 2024-05-01 | Tattoli Mark Damian | SVP, Gen Counsel & Secretary | Exercise or conversion | 250 | $0.00 | $0 | 11K |
| 2024-05-01 | Tattoli Mark Damian | SVP, Gen Counsel & Secretary | Tax withholding | 99 | $15.71 | $2K | 11K |
| 2024-05-01 | Teo Sow Hang | CAO & Treasurer | Exercise or conversion | 175 | $0.00 | $0 | 7K |
| 2024-05-01 | Teo Sow Hang | CAO & Treasurer | Tax withholding | 79 | $15.71 | $1K | 7K |
| 2024-04-01 | ANASTASIO CURT | Director | Exercise or conversion | 6K | $0.00 | $0 | 6K |
| 2024-04-01 | Carnes Martha Z. | Director | Exercise or conversion | 6K | $0.00 | $0 | 37K |
| 2024-04-01 | Klingensmith Harvey Robert | Director | Exercise or conversion | 6K | $0.00 | $0 | 33K |
| 2024-04-01 | Murray Katherine | Director | Exercise or conversion | 6K | $0.00 | $0 | 12K |
| 2024-04-01 | Straughen Michael | Director | Exercise or conversion | 6K | $0.00 | $0 | 23K |
| 2024-04-01 | Straughen Michael | Director | Tax withholding | 3K | $17.13 | $52K | 20K |
| 2024-04-01 | Temeng Kwaku | Director | Exercise or conversion | 6K | $0.00 | $0 | 16K |
| 2023-12-31 | Bruno Lawrence | Chairman and CEO | Exercise or conversion | 100K | $0.00 | $0 | 203K |
| 2023-12-31 | Bruno Lawrence | Chairman and CEO | Tax withholding | 38K | $17.66 | $679K | 164K |
| 2023-12-31 | Hill Christopher Scott | SVP & CFO | Tax withholding | 14K | $17.66 | $245K | 72K |
| 2023-12-31 | Hill Christopher Scott | SVP & CFO | Exercise or conversion | 36K | $0.00 | $0 | 86K |
| 2023-12-31 | Gresham Gwendolyn | SVP | Exercise or conversion | 15K | $0.00 | $0 | 30K |
| 2023-12-31 | Gresham Gwendolyn | SVP | Tax withholding | 6K | $17.66 | $100K | 24K |
| 2023-12-31 | Daniels Kevin | CAO & Treasurer | Tax withholding | 3K | $17.66 | $49K | 13K |
| 2023-12-31 | Daniels Kevin | CAO & Treasurer | Exercise or conversion | 7K | $0.00 | $0 | 16K |
| 2023-12-31 | Tattoli Mark Damian | SVP, Gen Counsel & Secretary | Tax withholding | 3K | $17.66 | $47K | 10K |
| 2023-12-31 | Tattoli Mark Damian | SVP, Gen Counsel & Secretary | Exercise or conversion | 7K | $0.00 | $0 | 13K |
| 2023-12-31 | Bruno Lawrence | Chairman and CEO | Tax withholding | 39K | $17.66 | $695K | 163K |
Form 4 filings are due within two business days of the trade. Insiders sell for many reasons that say nothing about the company; open-market buys are rarer.
Large holders (13D and 13G)
One row per reporting person with its latest filing, newest first. JSON4 holders report 5% or more of CLB in their latest filing, all on Schedule 13G (passive). The largest reported stake is Ariel Investments, LLC at 30.5% of the class (14,074,945 shares), filed 2026-08-14 for an event on 2026-06-30.
| Filed | Form | Holder | Shares | Of class | Event |
|---|---|---|---|---|---|
| 2026-08-14 | 13G/Ano. 7 | DISCIPLINED GROWTH INVESTORS INC /MNinvestment adviser | 3.0M | 6.6% | 2026-06-30 |
| 2026-08-14 | 13G/Ano. 9 | Ariel Investments, LLCinvestment adviser | 14.1M | 30.5% | 2026-06-30 |
| 2026-08-06 | 13G/Ano. 4 | BlackRock, Inc.parent holding company | 3.8M | 8.3% | 2026-07-31 |
| 2026-03-26 | 13G/Ano. 4 | The Vanguard Groupinvestment adviser | 0 | 0.0% | 2026-03-13 |
| 2026-02-12 | 13G/Ano. 12 | EARNEST PARTNERS LLCinvestment adviser | 3.2M | 6.9% | 2025-12-31 |
13F holders
Tracked managers holding CLB at their latest 13F. JSON5 of the 30 tracked managers held CLB at their latest 13F, $13.4M in total at quarter-end prices. Fisher Asset Management is the largest at $5.2M (0.0% of its portfolio) as of 2026-06-30. Over the prior quarter 3 added shares and 2 cut.
| Fund | Quarter | Shares | Value | Of portfolio | Change in shares |
|---|---|---|---|---|---|
| Fisher Asset Management | 2026-06-30 | 448K | $5.2M | 0.00% | -289K |
| Citadel Advisors | 2026-06-30 | 372K | $4.3M | 0.00% | +217K |
| D. E. Shaw & Co. | 2026-06-30 | 248K | $2.9M | 0.00% | +130K |
| AQR Capital Management | 2026-06-30 | 65K | $755K | 0.00% | +13K |
| Renaissance Technologies | 2026-06-30 | 15K | $169K | 0.00% | -36K |
Only the 30 tracked managers on the funds hub; a 13F reports long positions in US listed stock at quarter end, 45 days late, and says nothing about shorts or positions sold since.
What this page is
Core Laboratories in the regulatory record
Regulators publish company data in separate files that never sit next to each other: FINRA's twice-monthly short interest, its daily short sale volume, the SEC's fails-to-deliver counts, and each insider's Form 4. A company page puts those series for one ticker on one URL, with planned sales, large holders, 13F holders and financials beside them, so the short position, the daily flow, the settlement fails and what insiders are doing can be read together.
Each section has its own history table, a one-line summary of the latest figures and its own JSON and CSV links, and says when its source last updated.
This page follows Core Laboratories (CLB), SEC CIK 1958086, listed on NYSE, classified by the SEC as oil & gas field services, nec. The cross-market tables live on the short interest and insider transactions hubs.
Source and updates
- Short interest
- FINRA consolidated short interestSource: FINRA.Twice a month, about eight business days after settlement. Latest 2026-09-30.JSON and CSV
- Daily short volume
- FINRA Reg SHO daily filesSource: FINRA.Every trading day, the morning after FINRA posts it. Latest 2026-10-23.JSON and CSV
- Fails to deliver
- SEC fails-to-deliver dataSource: SEC.Twice a month, a few weeks after the half month ends. Latest 2026-09-29.JSON and CSV
- Large holders
- SEC EDGAR Schedule 13D and 13GSource: SEC.New filings appear shortly after the SEC posts them. A 13D is due within five business days of crossing 5%; a 13G follows the passive schedule. Latest 2026-08-14.JSON and CSV
- 13F holders
- SEC EDGAR Form 13F-HRSource: SEC.Quarterly, filed within 45 days of quarter end; 30 tracked managers. Latest 2026-06-30.JSON and CSV
- Earnings dates
- SEC EDGAR 8-K filings (Item 2.02)Source: SEC.Twice a day. Reported dates come from the company's 8-K filings; the next date is marked as an estimate until the 8-K arrives. Latest 2026-07-29.JSON and CSV
- Insider trades
- SEC EDGAR Form 4Source: SEC.New filings appear shortly after the SEC posts them; they're due two business days after the trade. Latest 2026-10-01.JSON and CSV
- Company record
- EDGAR filing index for CIK 1958086Ticker, name and exchange from the SEC's company list, refreshed weekly.
- Rate limits
- 10 requests a minute without a key, 30 with a free key from a free account.
How to read it
- Read the position against the flow: rising short interest with a high daily short share is new shorting; rising short interest with a normal short share is old shorts holding on.
- Insider buys next to a large short position are rare and stand out; insider sells next to one are common and mean little.
- Fails to deliver matter relative to the float, not in absolute shares; a million failed shares in a mega cap is noise.
Analysis of what the data shows, not advice. XOOMAR does not recommend buying, selling or holding anything.
Other companies the SEC classifies as oil & gas field services, nec
Other company pages
Datasets
Frequently Asked Questions
How much of CLB is sold short?
4,868,011 shares were held short at the 2026-09-30 settlement, 6.8 days of average volume. FINRA publishes the next count about eight business days after the 15th and the last business day of the month.
What is CLB's daily short volume?
On 2026-10-23, 121,040 of the 444,947 CLB shares reported to FINRA were sold short, 27.2% of the day's reported volume. Short volume is a flow for one day, not a position.
Does CLB have fails to deliver?
The SEC's latest file shows 752 CLB shares failed to deliver at settlement 2026-09-29. Fails are reported per settlement date and published twice a month with a lag.
Are CLB insiders buying or selling?
Insiders at CLB reported 1 open-market buy worth $54K in the last 90 days and no open-market sells. Latest filing: Teo Sow Hang (CAO & Treasurer) on 2026-10-01.
Who owns 5% or more of CLB?
4 holders report 5% or more of CLB in their latest filing, all on Schedule 13G (passive). The largest reported stake is Ariel Investments, LLC at 30.5% of the class (14,074,945 shares), filed 2026-08-14 for an event on 2026-06-30.
Which tracked 13F managers own CLB?
5 of the 30 tracked 13F managers held CLB shares at their latest filing, $13.4M in all. The largest: Ken Fisher's Fisher Asset Management (448K shares, $5.2M), Ken Griffin's Citadel Advisors (372K shares, $4.3M), D. E. Shaw & Co. (248K shares, $2.9M), Cliff Asness's AQR Capital Management (65K shares, $755K), Renaissance Technologies (15K shares, $169K).
Data on this page is provided for informational purposes only and is not financial advice. See our editorial policy.