BlackRock, Inc. filed an Amendment No. 17 to Schedule 13G/A reporting beneficial ownership of $5,467,592 shares of Great Lakes Dredge & Dock CORP as of 03/31/2026, representing 8.2% of the class.
The filing states BlackRock's Reporting Business Units hold 5,306,560 shares with sole voting power and 5,467,592 shares with sole dispositive power. The ownership is reported on behalf of BlackRock's business units in accordance with SEC Release No. 34-39538.
Positive
None.
Negative
None.
Insights
BlackRock reports an 8.2% beneficial stake via its Reporting Business Units.
BlackRock's Amendment No. 17 shows beneficial ownership of 5,467,592 shares as of 03/31/2026, with 5,306,560 shares carrying sole voting power. The filing attributes holdings to reporting units rather than other BlackRock business units.
Cash-flow treatment or plans for disposition are not stated in the excerpt; subsequent filings would disclose any change in voting or disposition intentions.
Key Figures
Beneficially owned:5,467,592 sharesPercent of class:8.2%Sole voting power:5,306,560 shares+2 more
5 metrics
Beneficially owned5,467,592 sharesheld as of 03/31/2026
Percent of class8.2%percent of common stock
Sole voting power5,306,560 sharesshares with sole voting power
Sole dispositive power5,467,592 sharesshares with sole dispositive power
Schedule 13G/A, Beneficial ownership, Sole dispositive power
3 terms
Schedule 13G/Aregulatory
"Amendment No. 17 to Schedule 13G/A reporting beneficial ownership"
A Schedule 13G/A is an amended public filing with the U.S. securities regulator that updates a previous Schedule 13G, disclosing when an individual or group holds a substantial (typically over 5%) stake in a company and is claiming a passive, non‑controlling intent. Investors monitor these updates because rising or falling holdings can signal changing confidence, potential future moves, or shifts in voting power — like watching a public ledger where large shareholders quietly adjust their positions.
Beneficial ownershipfinancial
"securities beneficially owned, or deemed to be beneficially owned, by certain business units"
Beneficial ownership means the person or entity that actually enjoys the benefits of owning shares or other assets — such as receiving dividends, voting rights, or price gains — even if the legal title is held in another name. For investors it matters because knowing who truly controls and profits from a company reveals who can influence decisions, exposes potential conflicts of interest or hidden concentration of power, and affects transparency and risk in the stock.
Sole dispositive powerfinancial
"Sole power to dispose or to direct the disposition of: 5,467,592"
Sole dispositive power is the exclusive legal authority to decide what happens to a security — for example, whether to sell, transfer, or retain shares — without needing anyone else’s permission. Investors care because it signals who truly controls the economic outcome of an investment: like holding the only key to a safe, the holder can realize gains or losses and may trigger regulatory reporting, insider rules, or influence over corporate ownership.
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
SCHEDULE 13G
UNDER THE SECURITIES EXCHANGE ACT OF 1934
(Amendment No. 17)
Great Lakes Dredge & Dock CORP
(Name of Issuer)
Common Stock
(Title of Class of Securities)
390607109
(CUSIP Number)
03/31/2026
(Date of Event Which Requires Filing of this Statement)
Check the appropriate box to designate the rule pursuant to which this Schedule is filed:
Rule 13d-1(b)
Rule 13d-1(c)
Rule 13d-1(d)
schemaVersion:
SCHEDULE 13G
CUSIP Number(s):
390607109
1
Names of Reporting Persons
BlackRock, Inc.
2
Check the appropriate box if a member of a Group (see instructions)
(a)
(b)
3
Sec Use Only
4
Citizenship or Place of Organization
DELAWARE
Number of Shares Beneficially Owned by Each Reporting Person With:
5
Sole Voting Power
5,306,560.00
6
Shared Voting Power
0.00
7
Sole Dispositive Power
5,467,592.00
8
Shared Dispositive Power
0.00
9
Aggregate Amount Beneficially Owned by Each Reporting Person
5,467,592.00
10
Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)
11
Percent of class represented by amount in row (9)
8.2 %
12
Type of Reporting Person (See Instructions)
HC
SCHEDULE 13G
Item 1.
(a)
Name of issuer:
Great Lakes Dredge & Dock CORP
(b)
Address of issuer's principal executive offices:
9811 KATY FREEWAY, SUITE 1200, HOUSTON, TEXAS, 77024
Item 2.
(a)
Name of person filing:
BlackRock, Inc.
In accordance with SEC Release No. 34-39538 (January 12, 1998), this Schedule 13G reflects the securities beneficially owned, or deemed to be beneficially owned, by certain business units (collectively, the "Reporting Business Units") of BlackRock, Inc. and its subsidiaries and affiliates. It does not include securities, if any, beneficially owned by other business units whose beneficial ownership of securities are disaggregated from that of the Reporting Business Units in accordance with such release.
(b)
Address or principal business office or, if none, residence:
BlackRock, Inc., 50 Hudson Yards New York, NY 10001
(c)
Citizenship:
See Item 4 of Cover Page
(d)
Title of class of securities:
Common Stock
(e)
CUSIP No.:
390607109
Item 3.
If this statement is filed pursuant to §§ 240.13d-1(b) or 240.13d-2(b) or (c), check whether the person filing is a:
(a)
Broker or dealer registered under section 15 of the Act (15 U.S.C. 78o);
(b)
Bank as defined in section 3(a)(6) of the Act (15 U.S.C. 78c);
(c)
Insurance company as defined in section 3(a)(19) of the Act (15 U.S.C. 78c);
(d)
Investment company registered under section 8 of the Investment Company Act of 1940 (15 U.S.C. 80a-8);
(e)
An investment adviser in accordance with § 240.13d-1(b)(1)(ii)(E);
(f)
An employee benefit plan or endowment fund in accordance with § 240.13d-1(b)(1)(ii)(F);
(g)
A parent holding company or control person in accordance with § 240.13d-1(b)(1)(ii)(G);
(h)
A savings associations as defined in Section 3(b) of the Federal Deposit Insurance Act (12 U.S.C. 1813);
(i)
A church plan that is excluded from the definition of an investment company under section 3(c)(14) of the Investment Company Act of 1940 (15 U.S.C. 80a-3);
(j)
A non-U.S. institution in accordance with § 240.13d-1(b)(1)(ii)(J). If filing as a non-U.S. institution in accordance with § 240.13d-1(b)(1)(ii)(J),
please specify the type of institution:
(k)
Group, in accordance with Rule 240.13d-1(b)(1)(ii)(K).
Item 4.
Ownership
(a)
Amount beneficially owned:
5,467,592
(b)
Percent of class:
8.2%
(c)
Number of shares as to which the person has:
(i) Sole power to vote or to direct the vote:
5,306,560
(ii) Shared power to vote or to direct the vote:
0
(iii) Sole power to dispose or to direct the disposition of:
5,467,592
(iv) Shared power to dispose or to direct the disposition of:
0
Item 5.
Ownership of 5 Percent or Less of a Class.
Not Applicable
Item 6.
Ownership of more than 5 Percent on Behalf of Another Person.
If any other person is known to have the right to receive or the power to direct the receipt of dividends from, or the proceeds from the sale of, such securities, a statement to that effect should be included in response to this item and, if such interest relates to more than 5 percent of the class, such person should be identified. A listing of the shareholders of an investment company registered under the Investment Company Act of 1940 or the beneficiaries of employee benefit plan, pension fund or endowment fund is not required.
Various persons have the right to receive or the power to direct the receipt of dividends from, or the proceeds from the sale of the common stock of Great Lakes Dredge & Dock CORP. No one person's interest in the common stock of Great Lakes Dredge & Dock CORP is more than five percent of the total outstanding common shares.
Item 7.
Identification and Classification of the Subsidiary Which Acquired the Security Being Reported on by the Parent Holding Company or Control Person.
If a parent holding company has filed this schedule, pursuant to Rule 13d-1(b)(ii)(G), so indicate under Item 3(g) and attach an exhibit stating the identity and the Item 3 classification of the relevant subsidiary. If a parent holding company has filed this schedule pursuant to Rule 13d-1(c) or Rule 13d-1(d), attach an exhibit stating the identification of the relevant subsidiary.
See Exhibit 99
Item 8.
Identification and Classification of Members of the Group.
Not Applicable
Item 9.
Notice of Dissolution of Group.
Not Applicable
Item 10.
Certifications:
By signing below I certify that, to the best of my knowledge and belief, the securities referred to above were acquired and are held in the ordinary course of business and were not acquired and are not held for the purpose of or with the effect of changing or influencing the control of the issuer of the securities and were not acquired and are not held in connection with or as a participant in any transaction having that purpose or effect, other than activities solely in connection with a nomination under § 240.14a-11.
SIGNATURE
After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.
