| Name | Relationship | Address | Signature | Signature date | CIK |
|---|---|---|---|---|---|
| Armstrong Dana A | Director | C/O GREAT LAKES DREDGE & DOCK CORP.,, 9811 KATY FREEWAY, SUITE 1200, HOUSTON | /s/Vivienne R. Schiffer, by Power of Attorney | 05 Jan 2026 | 0001907154 |
| Type | Sym | Class | Transaction | Value $ | Shares | Change % | * Price $ | Shares After | Date | Ownership | Footnotes |
|---|---|---|---|---|---|---|---|---|---|---|---|
| transaction | GLDD | Common Stock | Award | $0 | +1,829 | +28% | $0.000000 | 8,436 | 31 Dec 2025 | Direct |