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

SecurityGLDD / Great Lakes Dredge & Dock Corporation
InstitutionPrelude Capital Management, Llc
Latest Disclosed Ownership255,852 shares
Latest Disclosed Value $ 4,349,484
Prelude Capital Management, Llc ownership in GLDD / Great Lakes Dredge & Dock Corporation

On May 15, 2026 - Prelude Capital Management, Llc filed a 13F-HR form disclosing ownership of 255,852 shares of Great Lakes Dredge & Dock Corporation (US:GLDD) valued at $4,349,484 USD as of March 31, 2026. The entity filed a previous 13F-HR on August 14, 2025 disclosing 0 shares of Great Lakes Dredge & Dock Corporation. The current value of the position is $4,349,484 USD.

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.

Upgrade to unlock premium data and export to Excel .

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 255,852 255,852 4,349 0.3326
2025-08-14 2025-06-30 13F GREAT LAKES DREDGE & DOCK COM 390607109 0 -11,591 -100.00 0 -100.00
2025-05-15 2025-03-31 13F GREAT LAKES DREDGE & DOCK COM 390607109 11,591 11,591 101 0.0077
2020-05-15 2020-03-31 13F GREAT LAKES DREDGE & DOCK COM 390607109 0 -30,514 -100.00 0 -100.00
2020-02-14 2019-12-31 13F GREAT LAKES DREDGE & DOCK COM 390607109 30,514 -15,396 -33.54 346 -27.92 0.0132
2019-11-14 2019-09-30 13F GREAT LAKES DREDGE & DOCK COM 390607109 45,910 -4,190 -8.36 480 -13.20 0.0216
2019-08-14 2019-06-30 13F GREAT LAKES DREDGE & DOCK COM 390607109 50,100 47,769 2,049.29 553 2,533.33 0.0272
2019-05-15 2019-03-31 13F GREAT LAKES DREDGE & DOCK COM 390607109 2,331 -9,732 -80.68 21 -73.75 0.0012
2019-02-14 2018-12-31 13F GREAT LAKES DREDGE & DOCK COM 390607109 12,063 12,063 417.50 80 280.95 0.0054
2017-08-14 2017-06-30 13F GREAT LAKES DREDGE & DOCK COM 390607109 0 -100 -100.00 0 -100.00 0.0000
2017-05-15 2017-03-31 13F GREAT LAKES DREDGE & DOCK COM 390607109 100 0 0.00 0 0.0000
2017-02-14 2016-12-31 13F GREAT LAKES DREDGE & DOCK COM 390607109 100 100 0.00 0 0.0000
2016-02-16 2015-12-31 13F GREAT LAKES DREDGE & DOCK COM 390607109 0 -1,031 -100.00 0 -100.00
2015-11-16 2015-09-30 13F GREAT LAKES DREDGE & DOCK COM 390607109 1,031 1,031 0.00 5 0.0007
2014-11-14 2014-09-30 13F GREAT LAKES DREDGE & DOCK COM 390607109 0 -350 -100.00 0 -100.00
2014-08-14 2014-06-30 13F GREAT LAKES DREDGE & DOCK COM 390607109 350 350 -98.47 3 -98.24 0.0004
2014-02-14 2013-12-31 13F GREAT LAKES DREDGE & DOCK COM 390607109 0 -22,820 -100.00 0 -100.00
2013-11-14 2013-09-30 13F GREAT LAKES DREDGE & DOCK COM 390607109 22,820 4,143 22.18 170 16.44 0.0275
2013-08-14 2013-06-30 13F GREAT LAKES DREDGE & DOCK COM 390607109 18,677 6,891 58.47 146 84.81 0.0313
2013-05-22 2013-03-31 13F/A-1 GREAT LAKES DREDGE & DOCK COM 390607109 11,786 11,786 79 0.0147
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.