| 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 | 01 Oct 2025 | 0001907154 |
| Type | Sym | Class | Transaction | Value $ | Shares | Change % | * Price $ | Shares After | Date | Ownership | Footnotes |
|---|---|---|---|---|---|---|---|---|---|---|---|
| transaction | GLDD | Common Stock | Award | $0 | +2,002 | +43% | $0.000000 | 6,607 | 30 Sep 2025 | Direct |