Clean Harbors, Inc.
US ˙ NYSE ˙ US1844961078

SecurityCLH / Clean Harbors, Inc.
InstitutionAdvisor Group Holdings, Inc.
Latest Disclosed Ownership5,248 shares
Latest Disclosed Value $ 1,504,729
Advisor Group Holdings, Inc. reports 15.26% increase in ownership of CLH / Clean Harbors, Inc.

On May 15, 2026 - Advisor Group Holdings, Inc. filed a 13F-HR form disclosing ownership of 5,248 shares of Clean Harbors, Inc. (US:CLH) valued at $1,504,759 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 17, 2026 disclosing 4,553 shares of Clean Harbors, Inc.. This represents a change in shares of 15.26% during the quarter. The current value of the position is $1,504,234 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)
2026-05-15 2026-03-31 13F CLEAN HARBORS COM 184496107 5,248 695 15.26 1,505 40.96 0.0013
2026-02-17 2025-12-31 13F CLEAN HARBORS COM 184496107 4,553 365 8.72 1,068 7.78 0.0016
2025-11-14 2025-09-30 13F CLEAN HARBORS COM 184496107 4,188 195 4.88 990 7.26 0.0014
2025-09-04 2025-06-30 13F/A-1 LEAN HARBORS COM 184496107 3,993 -183 -4.38 923 12.15 0.0016
2025-08-13 2025-06-30 13F LEAN HARBORS COM 184496107 4,508 332 1,040 0.0012
2025-05-12 2025-03-31 13F CLEAN HARBORS COM 184496107 4,176 798 23.62 823 5.92 0.0018
2025-06-06 2024-12-31 13F/A-1 CLEAN HARBORS COM 184496107 3,378 -1,509 -30.88 777 -34.21 0.0017
2025-02-07 2024-12-31 13F CLEAN HARBORS COM 184496107 4,537 -350 1,084 0.0028
2024-11-13 2024-09-30 13F CLEAN HARBORS COM 184496107 4,887 -137 -2.73 1,181 3.96 0.0027
2024-08-13 2024-06-30 13F CLEAN HARBORS COM 184496107 5,024 12 0.24 1,136 12.70 0.0027
2024-05-10 2024-03-31 13F CLEAN HARBORS COM 184496107 5,012 -2,930 -36.89 1,009 -27.22 0.0023
2024-02-12 2023-12-31 13F CLEAN HARBORS COM 184496107 7,942 -4,332 -35.29 1,386 -32.54 0.0024
2023-11-13 2023-09-30 13F CLEAN HARBORS COM 184496107 12,274 33 0.27 2,054 1.03 0.0030
2023-08-21 2023-06-30 13F/A-1 CLEAN HARBORS COM 184496107 12,241 -6,739 -35.51 2,032 -24.38 0.0036
2023-08-10 2023-06-30 13F CLEAN HARBORS COM 184496107 12,241 -6,739 2,032 0.0006
2023-05-12 2023-03-31 13F CLEAN HARBORS COM 184496107 18,980 7,239 61.66 2,687 100.37 0.0051
2023-02-10 2022-12-31 13F CLEAN HARBORS COM 184496107 11,741 1,459 14.19 1,341 18.46 0.0027
2022-11-14 2022-09-30 13F CLEAN HARBORS COM 184496107 10,282 1,790 21.08 1,132 49.54 0.0026
2022-08-10 2022-06-30 13F CLEAN HARBORS COM 184496107 8,492 1,178 16.11 757 -62.19 0.0017
2022-05-04 2022-03-31 13F CLEAN HARBORS COM 184496107 7,314 844 13.04 2,002 214.29 0.0039
2022-02-03 2021-12-31 13F CLEAN HARBORS COM 184496107 6,470 -203 -3.04 637 -9.77 0.0012
2021-11-05 2021-09-30 13F CLEAN HARBORS COM 184496107 6,673 -510 -7.10 706 5.53 0.0015
2021-08-02 2021-06-30 13F CLEAN HARBORS COM 184496107 7,183 -475 -6.20 669 2.29 0.0014
2021-05-13 2021-03-31 13F CLEAN HARBORS COM 184496107 7,658 34 0.45 654 12.95 0.0016
2021-02-10 2020-12-31 13F CLEAN HARBORS COM 184496107 7,624 -612 -7.43 579 22.15 0.0015
2020-11-12 2020-09-30 13F CLEAN HARBORS COM 184496107 8,236 1,016 14.07 474 9.22 0.0014
2020-08-14 2020-06-30 13F CLEAN HARBORS COM 184496107 7,220 202 2.88 434 25.07 0.0015
2020-05-18 2020-03-31 13F CLEAN HARBORS COM 184496107 7,018 7,018 347 0.0014
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.