Clean Harbors, Inc.
MX ˙ BMV ˙ US1844961078
SecurityMX:CLH1 / Clean Harbors, Inc.
InstitutionMorgan Stanley
Latest Disclosed Ownership290,329 shares
Latest Disclosed Value $ 83,246,593
Morgan Stanley reports 9.87% increase in ownership of CLH1 / Clean Harbors, Inc.

On May 15, 2026 - Morgan Stanley filed a 13F-HR form disclosing ownership of 290,329 shares of Clean Harbors, Inc. (MX:CLH1) valued at $83,246,593 USD as of March 31, 2026. The entity filed a previous 13F-HR/A on May 27, 2026 disclosing 264,242 shares of Clean Harbors, Inc.. This represents a change in shares of 9.87% 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)
2026-05-15 2026-03-31 13F CLEAN HARBORS COM 184496107 290,329 26,087 9.87 83,247 34.35 0.0050
2026-05-27 2025-12-31 13F/A-1 CLEAN HARBORS COM 184496107 264,242 -9,638 -3.52 61,960 -2.58 0.0037
2026-02-13 2025-12-31 13F CLEAN HARBORS COM 184496107 264,242 -9,638 61,960
2026-05-27 2025-09-30 13F/A-1 CLEAN HARBORS COM 184496107 273,880 37,182 15.71 63,601 16.23 0.0039
2025-11-14 2025-09-30 13F CLEAN HARBORS COM 184496107 273,880 37,182 63,601 0.0039
2025-08-15 2025-06-30 13F CLEAN HARBORS COM 184496107 236,698 -9,630 -3.91 54,720 12.71 0.0036
2025-05-15 2025-03-31 13F CLEAN HARBORS COM 184496107 246,328 -60,188 -19.64 48,552 -31.17 0.0035
2025-05-15 2024-12-31 13F/A-1 CLEAN HARBORS COM 184496107 306,516 16,038 5.52 70,542 0.47 0.0049
2025-02-14 2024-12-31 13F CLEAN HARBORS COM 184496107 306,516 16,038 70,542 0.0049
2025-05-14 2024-09-30 13F/A-2 CLEAN HARBORS COM 184496107 290,478 9,923 3.54 70,212 10.66 0.0051
2025-02-14 2024-09-30 13F/A-1 CLEAN HARBORS COM 184496107 290,478 9,923 70,212 0.0051
2024-11-14 2024-09-30 13F CLEAN HARBORS COM 184496107 290,478 9,923 70,212 0.0006
2025-05-14 2024-06-30 13F/A-2 CLEAN HARBORS COM 184496107 280,555 -84,555 -23.16 63,448 -13.68 0.0049
2024-10-17 2024-06-30 13F/A-1 CLEAN HARBORS COM 184496107 280,555 -84,555 63,448 0.0049
2024-08-14 2024-06-30 13F CLEAN HARBORS COM 184496107 280,555 -84,555 63,448 0.0049
2024-10-17 2024-03-31 13F/A-2 CLEAN HARBORS COM 184496107 365,110 63,495 21.05 73,501 39.64 0.0059
2024-08-16 2024-03-31 13F/A-1 CLEAN HARBORS COM 184496107 365,110 63,495 73,501 0.0007
2024-05-15 2024-03-31 13F CLEAN HARBORS COM 184496107 365,110 63,495 73,501 0.0059
2024-08-16 2023-12-31 13F/A-1 CLEAN HARBORS COM 184496107 301,615 9,735 3.34 52,635 7.75 0.0046
2024-02-13 2023-12-31 13F CLEAN HARBORS COM 184496107 301,615 9,735 52,635 0.0046
2023-11-15 2023-09-30 13F CLEAN HARBORS COM 184496107 291,880 -7,626 -2.55 48,849 -0.81 0.0050
2023-08-14 2023-06-30 13F CLEAN HARBORS COM 184496107 299,506 -6,820 -2.23 49,248 12.77 0.0049
2023-05-15 2023-03-31 13F CLEAN HARBORS COM 184496107 306,326 42,755 16.22 43,670 45.19 0.0047
2023-02-14 2022-12-31 13F CLEAN HARBORS COM 184496107 263,571 -39,104 -12.92 30,079 -9.65 0.0034
2022-11-14 2022-09-30 13F CLEAN HARBORS COM 184496107 302,675 28,153 10.26 33,289 38.32 0.0045
2022-10-27 2022-06-30 13F/A-1 CLEAN HARBORS COM 184496107 274,522 43,986 19.08 24,066 -6.49 0.0031
2022-08-15 2022-06-30 13F CLEAN HARBORS COM 184496107 274,522 43,986 24,066 0.0031
2022-10-27 2022-03-31 13F/A-1 CLEAN HARBORS COM 184496107 230,536 -36,015 -13.51 25,736 -3.23 0.0035
2022-05-13 2022-03-31 13F CLEAN HARBORS COM 184496107 230,536 -36,015 25,736 0.0035
2022-02-14 2021-12-31 13F CLEAN HARBORS COM 184496107 266,551 54,076 25.45 26,594 20.50 0.0033
2021-11-15 2021-09-30 13F CLEAN HARBORS COM 184496107 212,475 10,662 5.28 22,070 17.41 0.0030
2021-08-23 2021-06-30 13F/A-1 CLEAN HARBORS COM 184496107 201,813 82,974 69.82 18,797 88.18 0.0025
2021-08-16 2021-06-30 13F CLEAN HARBORS COM 184496107 201,813 82,974 18,797 0.0005
2021-05-17 2021-03-31 13F CLEAN HARBORS COM 184496107 118,839 68,794 137.46 9,989 162.32 0.0015
2021-02-16 2020-12-31 13F CLEAN HARBORS COM 184496107 50,045 36,542 270.62 3,808 403.04 0.0006
2020-11-13 2020-09-30 13F CLEAN HARBORS COM 184496107 13,503 -25,104 -65.02 757 -67.30 0.0001
2020-08-14 2020-06-30 13F CLEAN HARBORS COM 184496107 38,607 23,116 149.22 2,315 191.19 0.0005
2020-05-26 2020-03-31 13F/A-1 CLEAN HARBORS COM 184496107 15,491 -32,213 -67.53 795 -80.56 0.0002
2020-05-15 2020-03-31 13F CLEAN HARBORS COM 184496107 15,491 -32,213 795 61.0726
2020-02-14 2019-12-31 13F CLEAN HARBORS COM 184496107 47,704 36,555 327.88 4,090 375.58 0.0010
2019-11-14 2019-09-30 13F CLEAN HARBORS COM 184496107 11,149 -114 -1.01 860 7.50 0.0002
2019-08-14 2019-06-30 13F CLEAN HARBORS COM 184496107 11,263 -433,415 -97.47 800 -97.48 0.0002
2019-05-15 2019-03-31 13F CLEAN HARBORS COM 184496107 444,678 30,842 7.45 31,807 55.74 0.0090
2019-02-14 2018-12-31 13F CLEAN HARBORS COM 184496107 413,836 339,551 457.09 20,423 284.18 0.0061
2019-04-23 2018-09-30 13F/A-2 CLEAN HARBORS COM 184496107 74,285 7,342 10.97 5,316 42.94 0.0013
2018-11-20 2018-09-30 13F/A-1 CLEAN HARBORS COM 184496107 74,285 0 5,316 0.0013
2018-11-14 2018-09-30 13F CLEAN HARBORS COM 184496107 74,285 7,342 5,316
2019-04-23 2018-06-30 13F/A-1 CLEAN HARBORS COM 184496107 66,943 -65,112 -49.31 3,719 -42.30 0.0010
2018-08-14 2018-06-30 13F CLEAN HARBORS COM 184496107 66,943 -65,112 3,719
2019-04-23 2018-03-31 13F/A-1 CLEAN HARBORS COM 184496107 132,055 2,492 1.92 6,445 -8.22 0.0018
2018-05-14 2018-03-31 13F CLEAN HARBORS COM 184496107 132,055 2,492 6,445
2019-04-23 2017-12-31 13F/A-1 CLEAN HARBORS COM 184496107 129,563 14,176 12.29 7,022 7.32 0.0019
2018-02-14 2017-12-31 13F CLEAN HARBORS COM 184496107 129,563 14,176 7,022
2017-11-14 2017-09-30 13F CLEAN HARBORS COM 184496107 115,387 39,260 51.57 6,543 53.99 0.0020
2017-08-11 2017-06-30 13F CLEAN HARBORS COM 184496107 76,127 -30,847 -28.84 4,249 -28.59 0.0013
2017-05-22 2017-03-31 13F/A-1 CLEAN HARBORS COM 184496107 106,974 11,103 11.58 5,950 11.53 0.0018
2017-05-12 2017-03-31 13F CLEAN HARBORS COM 184496107 106,974 5,950
2017-02-22 2016-12-31 13F/A-1 CLEAN HARBORS COM 184496107 95,871 47,637 98.76 5,335 130.55 0.0017
2017-02-13 2016-12-31 13F CLEAN HARBORS COM 184496107 95,871 5,335
2016-11-10 2016-09-30 13F CLEAN HARBORS COM 184496107 48,234 2,797 6.16 2,314 -2.24 0.0008
2016-08-12 2016-06-30 13F CLEAN HARBORS COM 184496107 45,437 28,690 171.31 2,367 186.56 0.0009
2016-05-12 2016-03-31 13F CLEAN HARBORS COM 184496107 16,747 -56,337 -77.09 826 -72.86 0.0003
2016-02-09 2015-12-31 13F CLEAN HARBORS COM 184496107 73,084 38,933 114.00 3,044 102.80 0.0011
2016-02-08 2015-09-30 13F/A-1 CLEAN HARBORS COM 184496107 34,151 -49,744 -59.29 1,501 -66.71 0.0006
2015-11-09 2015-09-30 13F CLEAN HARBORS COM 184496107 34,151 1,501
2015-08-12 2015-06-30 13F CLEAN HARBORS COM 184496107 83,895 26,997 47.45 4,509 39.60 0.0016
2015-05-14 2015-03-31 13F CLEAN HARBORS COM 184496107 56,898 15,757 38.30 3,230 63.38 0.0012
2015-02-13 2014-12-31 13F CLEAN HARBORS COM 184496107 41,141 -22,939 -35.80 1,977 -42.76 0.0007
2014-12-16 2014-09-30 13F/A-1 CLEAN HARBORS COM 184496107 64,080 -19,947 -23.74 3,454 -36.01 0.0013
2014-11-14 2014-09-30 13F CLEAN HARBORS COM 184496107 64,080 3,454
2014-08-12 2014-06-30 13F CLEAN HARBORS COM 184496107 84,027 46,569 124.32 5,398 163.19 0.0092
2014-05-13 2014-03-31 13F CLEAN HARBORS COM 184496107 37,458 -15,853 -29.74 2,051 -35.85 0.0009
2014-02-13 2013-12-31 13F CLEAN HARBORS COM 184496107 53,311 11,068 26.20 3,197 29.02 0.0014
2013-11-13 2013-09-30 13F CLEAN HBRS INC COM ST COM 184496107 42,243 -98,723 -70.03 2,478 -65.21 0.0012
2013-08-08 2013-06-30 13F CLEAN HBRS INC COM ST COM 184496107 140,966 140,966 7,123 0.0036
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.