| Name | Relationship | Address | Signature | Signature date | CIK |
|---|---|---|---|---|---|
| GERSTENBERG ERIC W | CO-CEO | C/O CLEAN HARBORS ENVIRON. SERVICES INC., 42 LONGWATER DRIVE, NORWELL | /s/ Eric W. Gerstenberg | 17 Dec 2025 | 0001211558 |
| Type | Sym | Class | Transaction | Value $ | Shares | Change % | * Price $ | Shares After | Date | Ownership | Footnotes |
|---|---|---|---|---|---|---|---|---|---|---|---|
| transaction | CLH | Common Stock | Sale | $144,781 | -601 | -1.2% | $240.90 | 50,454 | 16 Dec 2025 | Direct |