Clean Harbors, Inc. (CLH) Shareholders & Insider Trades
Clean Harbors shareholders at a glance
The largest holder of Clean Harbors stock is BlackRock Advisors LLC, with 4.6 million shares (8.75% of the company), worth about $1.46 billion as of September 25, 2026. The 10 largest holders together own 43.2%.
In Q2 2026, 679 institutional holdings reports listed shares worth $14.90 billion.
Insiders reported 71 transactions in the last two years: 26 sales worth $101.88 million and 3 purchases. The newest one on file is from May 11, 2026 (Polito Karyn, Director).
Major holders as of September 25, 2026; quarterly totals from institutional holdings reports (latest Q2 2026); insider transactions on file through May 11, 2026.
Clean Harbors, Inc.
Shareholders Summary
2026Q2
Ownership by Type
Geographic Distribution
Largest Clean Harbors shareholders
| Holder | Shares | % of company | Value |
|---|---|---|---|
| BlackRock Advisors LLC | 4.6 million | 8.75% | $1.5B |
| Wellington Trust Co., NA | 3.2 million | 5.98% | $995.0M |
| Fidelity Management & Research Co. LLC | 3.0 million | 5.68% | $946.0M |
| Alan McKim4.286 % | 2.3 million | 4.29% | $713.0M |
| Vanguard Capital Management LLC | 2.2 million | 4.13% | $688.0M |
| Vanguard Portfolio Management LLC | 2.0 million | 3.76% | $625.0M |
| Janus Henderson Investors US LLC | 1.6 million | 3.03% | $504.0M |
| State Street Corporation | 1.6 million | 3.00% | $499.0M |
| D1 Capital Partners LP | 1.3 million | 2.49% | $415.0M |
| Geode Capital Management LLC | 1.1 million | 2.14% | $356.0M |
As of September 25, 2026.
Clean Harbors institutional holdings by quarter
| Quarter | Reports | Shares | Value |
|---|---|---|---|
| Q2 2026 | 679 | – | $14.9B |
| Q1 2026 | 640 | 49.3 million | $14.1B |
| Q4 2025 | 586 | 51.8 million | $12.1B |
| Q3 2025 | 587 | 50.0 million | $11.6B |
| Q2 2025 | 595 | 49.3 million | $11.4B |
| Q1 2025 | 590 | 49.1 million | $9.8B |
| Q4 2024 | 596 | 49.2 million | $11.3B |
| Q3 2024 | 598 | 48.0 million | $11.5B |
Shares and value held by institutions that file quarterly holdings reports (options not included).
Clean Harbors insider trades
| Insider | Date | Title | Transaction | Value |
|---|---|---|---|---|
| Polito Karyn | May 11, 2026 | Director | Stock Award(Grant) at price 295.13 per share. | $135,760 |
| Polito Karyn | May 11, 2026 | Director | Purchase at price 295.13 per share. | $135,760 |
| Robertson Andrea | May 11, 2026 | Director | Stock Gift at price 0.00 per share. | – |
| Gerstenberg Eric W | Mar 18, 2026 | Chief Executive Officer | Sale at price 293.00 per share. | $293,000 |
| Reed Marcy L. | Mar 18, 2026 | Director | Sale at price 287.94 per share. | $240,718 |
| Weber Brian P | Mar 17, 2026 | Officer | Sale at price 293.39 per share. | $1.4M |
| Mckim Alan S | Mar 4, 2026 | Chief Technology Officer | Sale at price 292.65 per share. | $29.3M |
| Gerstenberg Eric W | Feb 23, 2026 | Chief Executive Officer | Sale at price 279.86 per share. | $699,650 |
| Dugas Eric J. | Feb 20, 2026 | Chief Financial Officer | Sale at price 281.31 per share. | $784,292 |
| Gabriel Sharon M | Feb 20, 2026 | Officer | Sale at price 282.07 per share. | $998,528 |
| Mckim Alan S | Feb 19, 2026 | Chief Technology Officer | Stock Gift at price 0.00 per share. | – |
| Welch John R. Ph.D. | Feb 19, 2026 | Director | Sale at price 273.07 per share. | $204,802 |
Newest 12 of 71 insider transactions in the last two years.
Questions and answers
Who owns the most Clean Harbors stock?
BlackRock Advisors LLC, with 8.75% of the company (as of September 25, 2026). Next: Wellington Trust Co., NA (5.98%) and Fidelity Management & Research Co. LLC (5.68%).
How many institutions own Clean Harbors stock?
679 institutional holdings reports listed Clean Harbors shares in Q2 2026 worth $14.90 billion.
Are Clean Harbors insiders buying or selling the stock?
In the last two years insiders reported 26 sales and 3 purchases (71 transactions in all); the newest on file is from May 11, 2026.
