Clean Harbors, Inc.
MX ˙ BMV ˙ US1844961078
SecurityMX:CLH1 / Clean Harbors, Inc.
InstitutionImpax Asset Management Group plc
Latest Disclosed Ownership122,986 shares
Latest Disclosed Value $ 35,263,776
Impax Asset Management Group plc reports 17.24% decrease in ownership of CLH1 / Clean Harbors, Inc.

On May 12, 2026 - Impax Asset Management Group plc filed a 13F-HR form disclosing ownership of 122,986 shares of Clean Harbors, Inc. (MX:CLH1) valued at $35,263,776 USD as of March 31, 2026. The entity filed a previous 13F-HR on January 29, 2026 disclosing 148,605 shares of Clean Harbors, Inc.. This represents a change in shares of -17.24% during the quarter.

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)
2026-05-12 2026-03-31 13F Clean Harbors Common Stock 184496107 122,986 -25,619 -17.24 35,264 1.20 0.2458
2026-01-29 2025-12-31 13F Clean Harbors Common Stock 184496107 148,605 -103,536 -41.06 34,845 -39.60 0.2180
2025-11-06 2025-09-30 13F Clean Harbors Common Stock 184496107 252,141 -104,114 -29.22 57,690 -29.00 0.3367
2025-08-08 2025-06-30 13F Clean Harbors Common Stock 184496107 356,255 -126,998 -26.28 81,254 -13.56 0.4672
2025-04-29 2025-03-31 13F Clean Harbors Common Stock 184496107 483,253 48,447 11.14 94,002 -4.90 0.5661
2025-02-04 2024-12-31 13F Clean Harbors Common Stock 184496107 434,806 -5,171 -1.18 98,841 -5.95 0.4476
2024-11-06 2024-09-30 13F/A-1 Clean Harbors Common Stock 184496107 439,977 -5,863 -1.32 105,098 5.46 0.4138
2024-10-30 2024-09-30 13F Clean Harbors Common Stock 184496107 439,977 -5,863 105,098 0.4142
2024-11-08 2024-06-30 13F/A-1 Clean Harbors Common Stock 184496107 445,840 -119,774 -21.18 99,658 -11.53 0.4057
2024-08-05 2024-06-30 13F Clean Harbors Common Stock 184496107 445,840 -119,774 99,658 0.4061
2024-04-30 2024-03-31 13F Clean Harbors Common Stock 184496107 565,614 3,239 0.58 112,647 15.94 0.4312
2024-01-26 2023-12-31 13F Clean Harbors Common Stock 184496107 562,375 -47,916 -7.85 97,163 -3.89 0.3901
2023-11-07 2023-09-30 13F/A-1 Clean Harbors Common Stock 184496107 610,291 -70,180 -10.31 101,095 -8.75 0.4516
2023-11-07 2023-09-30 13F Clean Harbors Common Stock 184496107 610,291 101,095
2023-08-07 2023-06-30 13F Clean Harbors Common Stock 184496107 680,471 -169,331 -19.93 110,784 -7.68 0.4452
2023-05-10 2023-03-31 13F Clean Harbors Common Stock 184496107 849,802 -233,125 -21.53 120,002 -1.95 0.5014
2023-02-09 2022-12-31 13F Clean Harbors Common Stock 184496107 1,082,927 -45,825 -4.06 122,388 -0.49 0.5476
2022-11-08 2022-09-30 13F Clean Harbors Common Stock 184496107 1,128,752 -184,708 -14.06 122,987 7.82 0.6322
2022-08-11 2022-06-30 13F/A-2 Clean Harbors Common Stock 184496107 1,313,460 80,702 6.55 114,070 -16.35 0.5560
2022-08-02 2022-06-30 13F Clean Harbors Common Stock 184496107 1,232,758 0 136,369 0.5636
2022-05-16 2022-03-31 13F Clean Harbors Common Stock 184496107 1,232,758 -367,468 -22.96 136,369 -13.82 0.5636
2022-02-14 2021-12-31 13F Clean Harbors Common Stock 184496107 1,600,226 124,801 8.46 158,244 4.23 0.5786
2021-11-12 2021-09-30 13F Clean Harbors Common Stock 184496107 1,475,425 15,629 1.07 151,826 12.73 0.6236
2021-08-05 2021-06-30 13F Clean Harbors Common Stock 184496107 1,459,796 93,760 6.86 134,686 18.41 0.5940
2021-05-14 2021-03-31 13F Clean Harbors Common Stock 184496107 1,366,036 -119,665 -8.05 113,741 1.64 0.5820
2021-02-16 2020-12-31 13F Clean Harbors Common Stock 184496107 1,485,701 3,182 0.21 111,901 36.19 0.7120
2020-11-12 2020-09-30 13F Clean Harbors Common Stock 184496107 1,482,519 189,652 14.67 82,168 5.96 0.7189
2020-08-14 2020-06-30 13F Clean Harbors Common Stock 184496107 1,292,867 312,490 31.87 77,546 55.91 0.7957
2020-05-15 2020-03-31 13F Clean Harbors Common Stock 184496107 980,377 190,235 24.08 49,738 -25.77 0.6618
2020-02-13 2019-12-31 13F Clean Harbors Common Stock 184496107 790,142 31,603 4.17 67,002 15.76 0.7475
2019-11-14 2019-09-30 13F Clean Harbors Common Stock 184496107 758,539 -38,036 -4.77 57,881 2.20 0.7539
2019-08-13 2019-06-30 13F Clean Harbors Common Stock 184496107 796,575 30,444 3.97 56,636 3.35 0.7357
2019-05-13 2019-03-31 13F Clean Harbors Common Stock 184496107 766,131 40,060 5.52 54,801 52.94 0.7543
2019-02-14 2018-12-31 13F Clean Harbors Common Stock 184496107 726,071 53,192 7.91 35,832 -24.57 0.5840
2018-11-14 2018-09-30 13F Clean Harbors Common Stock 184496107 672,879 672,879 47,503 0.6821
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.