Great Lakes Dredge & Dock Corporation
US ˙ NasdaqGS ˙ US3906071093
DETTE SYMBOL ER IKKE LÆNGERE AKTIVT

SecurityGLDD / Great Lakes Dredge & Dock Corporation
InstitutionHarvey Partners, LLC
Latest Disclosed Ownership610,000 shares
Ownership 0.90%
Harvey Partners, LLC ownership in GLDD / Great Lakes Dredge & Dock Corporation

2026-05-15 - Harvey Partners, LLC has filed an SCHEDULE 13G/A form with the Securities and Exchange Commission (SEC) disclosing ownership of 610,000 shares of Great Lakes Dredge & Dock Corporation (US:GLDD). This represents 0.9 percent ownership of the company. In their previous filing dated 2024-02-14 , Harvey Partners, LLC had reported owning 3,419,000 shares, indicating a decrease of -82.16 percent.

Institutional Ownership: 13D/G Filings

This table shows a history of the 13D/G filings made by the investor and/or investor group. Note that the share values in this table are not directly comparable to any numbers shown in the 13F table (if any).

File
Date
Effective
Date
Form Prev
Shares
Latest
Shares
ΔShares
(Percent)
Ownership
(Percent)
ΔOwnership
(Percent)
2026-05-15 2026-05-15 13G/A 3,419,000 610,000 -82.16 0.90 -82.35
2024-02-14 2024-02-14 13G/A 3,445,726 3,419,000 -0.78 5.10 -1.92
2023-02-14 2023-02-14 13G 3,445,726 5.20

Important Note: One of the primary uses of the 13D/G filings is to evaluate the ability of a firm to control a company (ie, the "beneficial ownership"). To that end, firms are required to report not just direct holdings in companies, but indirect holdings that they control. For investment firms, these indirect holdings can include shares in funds they manage, advisory accounts, and in the case of activist campaigns, pledged votes. Therefore, share counts listed in 13D/G filings can differ significantly than share counts listed in 13F filings.

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 GREAT LAKES DREDGE & DOCK COM 390607109 610,000 -3,093,215 -83.53 10,370 -78.66 0.8253
2026-02-17 2025-12-31 13F GREAT LAKES DREDGE & DOCK COM 390607109 3,703,215 2,664 0.07 48,586 9.50 4.3054
2025-11-14 2025-09-30 13F GREAT LAKES DREDGE & DOCK COM 390607109 3,700,551 -32,449 -0.87 44,370 -2.50 3.9449
2025-08-14 2025-06-30 13F GREAT LAKES DREDGE & DOCK COM 390607109 3,733,000 0 0.00 45,505 40.11 4.4624
2025-05-15 2025-03-31 13F GREAT LAKES DREDGE & DOCK COM 390607109 3,733,000 29,000 0.78 32,477 -22.34 3.7876
2025-02-14 2024-12-31 13F GREAT LAKES DREDGE & DOCK COM 390607109 3,704,000 56,500 1.55 41,818 8.88 4.6444
2024-11-14 2024-09-30 13F GREAT LAKES DREDGE & DOCK COM 390607109 3,647,500 325,500 9.80 38,408 31.68 4.3729
2024-08-14 2024-06-30 13F GREAT LAKES DREDGE & DOCK COM 390607109 3,322,000 -97,000 -2.84 29,167 -2.50 3.5074
2024-05-15 2024-03-31 13F GREAT LAKES DREDGE & DOCK COM 390607109 3,419,000 0 0.00 29,916 13.94 3.1692
2024-02-14 2023-12-31 13F GREAT LAKES DREDGE & DOCK COM 390607109 3,419,000 -11,000 -0.32 26,258 -3.95 2.9825
2023-11-14 2023-09-30 13F GREAT LAKES DREDGE & DOCK COM 390607109 3,430,000 75,000 2.24 27,337 -0.14 3.4660
2023-08-14 2023-06-30 13F GREAT LAKES DREDGE & DOCK COM 390607109 3,355,000 15,000 0.45 27,377 50.95 3.3479
2023-05-15 2023-03-31 13F GREAT LAKES DREDGE & DOCK COM 390607109 3,340,000 -105,726 -3.07 18,136 -11.54 2.2443
2023-02-14 2022-12-31 13F GREAT LAKES DREDGE & DOCK COM 390607109 3,445,726 729,726 26.87 20,502 -0.42 2.6049
2022-11-14 2022-09-30 13F GREAT LAKES DREDGE & DOCK COM 390607109 2,716,000 953,500 54.10 20,588 -10.90 3.0132
2022-08-15 2022-06-30 13F GREAT LAKES DREDGE & DOCK COM 390607109 1,762,500 622,500 54.61 23,106 44.47 5.0802
2022-05-16 2022-03-31 13F GREAT LAKES DREDGE & DOCK COM 390607109 1,140,000 570,352 100.12 15,994 78.60 3.9430
2022-02-14 2021-12-31 13F GREAT LAKES DREDGE & DOCK COM 390607109 569,648 149,648 35.63 8,955 41.29 3.6386
2021-11-15 2021-09-30 13F GREAT LAKES DREDGE & DOCK COM 390607109 420,000 0 0.00 6,338 3.28 4.7387
2021-08-16 2021-06-30 13F GREAT LAKES DREDGE & DOCK COM 390607109 420,000 -100,000 -19.23 6,137 -19.06 4.2499
2021-05-17 2021-03-31 13F GREAT LAKES DREDGE & DOCK COM 390607109 520,000 7,500 1.46 7,582 12.34 5.2328
2021-02-16 2020-12-31 13F GREAT LAKES DREDGE & DOCK COM 390607109 512,500 182,500 55.30 6,749 115.07 4.6885
2020-11-16 2020-09-30 13F GREAT LAKES DREDGE & DOCK COM 390607109 330,000 -95,000 -22.35 3,138 -20.27 4.0767
2020-08-14 2020-06-30 13F GREAT LAKES DREDGE & DOCK COM 390607109 425,000 -464,654 -52.23 3,936 -46.70 4.7458
2020-06-23 2020-03-31 13F/A-1 GREAT LAKES DREDGE & DOCK COM 390607109 889,654 152,500 20.69 7,384 -11.59 6.6816
2020-05-15 2020-03-31 13F GREAT LAKES DREDGE & DOCK COM 390607109 889,654 152,500 7,384 6,681,627.3346
2020-02-14 2019-12-31 13F GREAT LAKES DREDGE & DOCK COM 390607109 737,154 100,782 15.84 8,352 25.59 4.7466
2019-11-14 2019-09-30 13F GREAT LAKES DREDGE & DOCK COM 390607109 636,372 348,772 121.27 6,650 109.45 4.8061
2019-08-27 2019-06-30 13F/A-1 GREAT LAKES DREDGE & DOCK COM 390607109 287,600 7,600 2.71 3,175 27.25 4.3790
2019-08-14 2019-06-30 13F GREAT LAKES DREDGE & DOCK COM 390607109 287,600 7,600 3,175
2019-05-15 2019-03-31 13F GREAT LAKES DREDGE & DOCK COM 390607109 280,000 8,500 3.13 2,495 38.84 4.1306
2019-02-14 2018-12-31 13F GREAT LAKES DREDGE & DOCK COM 390607109 271,500 0 0.00 1,797 6.77 4.5194
2018-11-14 2018-09-30 13F GREAT LAKES DREDGE & DOCK COM 390607109 271,500 89,000 48.77 1,683 75.68 2.3425
2018-08-14 2018-06-30 13F GREAT LAKES DREDGE & DOCK COM 390607109 182,500 -78,767 -30.15 958 -20.30 1.2481
2018-05-16 2018-03-31 13F/A-1 GREAT LAKES DREDGE & DOCK COM 390607109 261,267 261,267 1,202 1.7778
2018-05-15 2018-03-31 13F GREAT LAKES DREDGE & DOCK COM 390607109 261,267 1,202 1.7778
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.