코어 연구소 Inc.
US ˙ NYSE ˙ US21867A1051

SecurityCLB / Core Laboratories Inc.
InstitutionJanus Henderson Group Plc
Latest Disclosed Ownership19,854 shares
Latest Disclosed Value $ 333,845
Janus Henderson Group Plc ownership in CLB / Core Laboratories Inc.

On May 18, 2026 - Janus Henderson Group Plc filed a 13F-HR/A form disclosing ownership of 19,854 shares of Core Laboratories Inc. (US:CLB) valued at $333,349 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 17, 2026 disclosing 19,854 shares of Core Laboratories Inc.. This represents a change in shares of 0.00% during the quarter. The current value of the position is $257,109 USD.

Institutional Ownership: 13F and NPORT Filings

The Security and Class in the table below are shown exactly as filed by the investor. We do our best to track continuity of investments through acquisitions, and this will be reflected in the table as changes in names. In addition to descriptive data, performance of the investment is shown over time. To calculate quarterly performance, we first calculate cost basis of the shares purchased during the quarter, then use that to calculate gross profit. Quarterly return is Gross Profit / Starting Portfolio value.

Note that cost basis is calculated and stored in thousands, so small quarterly changes in shares frequently result in a cost basis of zero.

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Disclosed Equity Positions (from 13F/NPORT Filings)
File
Date		 Effective
Date		Form Security Class ID Avg Price
Paid (Est)		 Reported
Shares		 ΔShares ΔShares
(%)		 Reported
Value
(x1000)		 ΔValue
(%)		 Alloc
(%)		 ΔAlloc ΔAlloc (%) Cost Basis
(x1000)		 Unrealized
Gain/Loss
(x1000)
2026-05-18 2026-03-31 13F/A-1 CORE LABORATORIES COM 21867A105 19,854 0 0.00 334 4.72 0.0001
2026-05-15 2026-03-31 13F CORE LABORATORIES COM 21867A105 19,854 0 0.00 334 4.72 0.0001
2026-02-17 2025-12-31 13F CORE LABORATORIES COM 21867A105 19,854 0 0.00 318 29.80 0.0001
2025-11-14 2025-09-30 13F CORE LABORATORIES COM 21867A105 19,854 0 0.00 246 6.99 0.0001
2025-08-14 2025-06-30 13F CORE LABORATORIES COM 21867A105 19,854 0 0.00 229 -24.67 0.0001
2025-05-15 2025-03-31 13F CORE LABORATORIES COM 21867A105 19,854 0 0.00 304 -11.37 0.0002
2025-02-14 2024-12-31 13F CORE LABORATORIES COM 21867A105 19,854 0 0.00 344 -6.54 0.0002
2024-11-14 2024-09-30 13F CORE LABORATORIES COM 21867A105 19,854 0 0.00 368 -8.71 0.0002
2024-08-14 2024-06-30 13F CORE LABORATORIES COM 21867A105 19,854 -240 -1.19 402 17.20 0.0002
2024-05-15 2024-03-31 13F CORE LABORATORIES COM 21867A105 20,094 1 0.00 343 -3.11 0.0002
2024-02-14 2023-12-31 13F CORE LABORATORIES COM 21867A105 20,093 -35 -0.17 355 -26.71 0.0002
2023-11-14 2023-09-30 13F CORE LABORATORIES COM 21867A105 20,128 1 0.00 483 3.43 0.0003
2023-08-14 2023-06-30 13F CORE LABORATORIES COM 21867A105 20,127 273 1.38 468 6.86 0.0003
2023-05-15 2023-03-31 13F CORE LABORATORIES N V COM N22717107 19,854 19,854 438 0.0003
2022-08-15 2022-06-30 13F CORE LABORATORIES N V COM N22717107 0 -8,771 -100.00 0 -100.00
2022-05-16 2022-03-31 13F CORE LABORATORIES N V COM N22717107 8,771 8,771 277 0.0001
2019-04-30 2019-03-31 13F CORE LABORATORIES N V COM N22717107 0 -5,420 -100.00 0 -100.00
2019-02-06 2018-12-31 13F CORE LABORATORIES N V COM N22717107 5,420 0 0.00 323 -48.57 0.0002
2018-11-09 2018-09-30 13F CORE LABORATORIES N V COM N22717107 5,420 -2,004 -26.99 628 -32.98 0.0003
2018-08-10 2018-06-30 13F CORE LABORATORIES N V COM N22717107 7,424 5,304 250.19 937 309.17 0.0005
2018-05-14 2018-03-31 13F CORE LABORATORIES N V COM N22717107 2,120 0 0.00 229 -1.29 0.0001
2018-03-12 2017-12-31 13F/A-1 CORE LABORATORIES N V COM N22717107 2,120 -8,144 -79.35 232 -77.10 0.0001
2018-02-09 2017-12-31 13F CORE LABORATORIES N V COM N22717107 2,120 -8,144 232
2017-11-14 2017-09-30 13F CORE LABORATORIES N V COM N22717107 10,264 5,262 105.20 1,013 100.20 0.0006
2017-08-17 2017-06-30 13F/A-1 CORE LABORATORIES N V COM N22717107 5,002 64 1.30 506 -11.38 0.0003
2017-08-14 2017-06-30 13F CORE LABORATORIES N V COM N22717107 5,002 64 506
2017-05-03 2017-03-31 13F CORE LABORATORIES N V COM N22717107 4,938 0 0.00 571 -3.71 0.0040
2017-01-30 2016-12-31 13F CORE LABORATORIES N V COM N22717107 4,938 700 16.52 593 24.58 0.0044
2016-10-24 2016-09-30 13F CORE LABORATORIES N V COM N22717107 4,238 0 0.00 476 -9.33 0.0035
2016-07-29 2016-06-30 13F CORE LABORATORIES N V COM N22717107 4,238 -2,655 -38.52 525 -32.26 0.0044
2016-05-12 2016-03-31 13F CORE LABORATORIES N V COM N22717107 6,893 0 0.00 775 3.47 0.0063
2016-02-03 2015-12-31 13F CORE LABORATORIES N V COM N22717107 6,893 0 0.00 749 9.02 0.0060
2015-11-16 2015-09-30 13F CORE LABORATORIES N V COM N22717107 6,893 0 0.00 687 -12.60 0.0061
2015-08-17 2015-06-30 13F CORE LABORATORIES N V COM N22717107 6,893 0 0.00 786 9.17 0.0062
2015-06-02 2015-03-31 13F/A-1 CORE LABORATORIES N V COM N22717107 6,893 0 0.00 720 -13.25 0.0056
2015-05-15 2015-03-31 13F CORE LABORATORIES N V COM N22717107 6,893 720
2015-02-12 2014-12-31 13F CORE LABORATORIES N V COM N22717107 6,893 0 0.00 830 -17.74 0.0060
2014-11-12 2014-09-30 13F CORE LABORATORIES N V COM N22717107 6,893 0 0.00 1,009 -12.41 0.0095
2014-08-13 2014-06-30 13F CORE LABORATORIES N V COM N22717107 6,893 0 0.00 1,152 -15.73 0.0108
2014-05-08 2014-03-31 13F CORE LABORATORIES N V COM N22717107 6,893 3,320 92.92 1,367 100.44 0.0133
2014-01-14 2013-12-31 13F CORE LABORATORIES N V COM N22717107 3,573 0 0.00 682 12.73 0.0069
2013-11-12 2013-09-30 13F CORE LABORATORIES N V COM N22717107 3,573 0 0.00 605 11.83 0.0067
2013-08-15 2013-06-30 13F CORE LABORATORIES N V COM N22717107 3,573 3,573 541 0.0063
Legend
Shares
The total number of shares held by the institution at the end of the reporting period (the effective date). This is provided in the filing.
Value
The total value of the shares as of the effective date. This is provided in the filing.
Avg. Share Price
The weighted average share price of the shares held by the institution. We use FIFO accounting to determine this price
Class
This is the security class as indicated by the filer. There are a variety of values for this field. Common values include "EC" = equity common, "EP" - equity preferred
Allocation (%)
The percent of the institution's portfolio that this position represents. This is provided in NPORT filings. For 13F filings, we calculate it.
Change in Allocation
The change in allocation from the prior reporting period. This is calculated as current allocation - prior allocation.
Change in Allocation (%)
The percent change in allocation from the prior reporting period. This is calculated as (current allocation - prior allocation) / prior allocation.
Cost Basis
The total cost of the shares held. This is calculated as reported shares * avg. share price
Unrealized Gain/Loss
This is the market value of the position as of the effective date minus the cost basis.