[Form 4/A] Great Lakes Dredge & Dock CORP Amended Insider Trading Activity

Rhea-AI Filing Summary

Great Lakes Dredge & Dock Corp senior vice president David Johanson reported an amended insider transaction reflecting a stock-based compensation award. On May 8, 2025, he acquired 13,179 shares of common stock at a stated price of $0.00 per share, increasing his direct holdings to 104,063.2594 shares.

The filing clarifies the vesting schedule for the related Restricted Stock Units. An earlier report had shown vesting beginning on March 15, 2026, but the corrected disclosure states that vesting will instead begin on May 8, 2026. This change is described as an administrative correction to the prior report.

SEC Form 4

FORM 4

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934
or Section 30(h) of the Investment Company Act of 1940

OMB APPROVAL

OMB Number:			3235-0287
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Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan for the purchase or sale of equity securities of the issuer that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.

1. Name and Address of Reporting Person^*

JOHANSON DAVID

(Last) (First) (Middle)

C/O GREAT LAKES DREDGE & DOCK CORP.

9811 KATY FREEWAY, SUITE 1200

(Street)

HOUSTON TEXAS 77024

(City) (State) (Zip)

UNITED STATES

(Country)

2. Issuer Name and Ticker or Trading Symbol
Great Lakes Dredge & Dock CORP [ GLDD ]

5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)

	Director		10% Owner
X	Officer (give title below)		Other (specify below)
	SVP-Project Acquisition & Ops

2a. Foreign Trading Symbol

3. Date of Earliest Transaction (Month/Day/Year)
05/08/2025

6. Individual or Joint/Group Filing (Check Applicable Line)

X	Form filed by One Reporting Person
	Form filed by More than One Reporting Person

4. If Amendment, Date of Original Filed (Month/Day/Year)
05/12/2025

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	3. Transaction Code (Instr. 8)		4. Securities Acquired (A) or Disposed Of (D) (Instr. 3, 4 and 5)			5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4)	6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
			Code	V	Amount	(A) or (D)	Price
Common Stock	05/08/2025		A		13,179	A	(1)	104,063.2594	D

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	4. Transaction Code (Instr. 8)		5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)		6. Date Exercisable and Expiration Date (Month/Day/Year)		7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4)		8. Price of Derivative Security (Instr. 5)	9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)	10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares

Explanation of Responses:

1. This Form 4/A is being filed to correct an administrative error in the original Form 4 filed on May 12, 2025 in which the vesting date for the Restricted Stock Units was inadvertently reported as beginning on March 15, 2026. The correct vesting date begins on May 8, 2026.

	/s/Vivienne R. Schiffer, by Power of Attorney	03/25/2026
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 4 (b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.
* Form 4: SEC 1474 (03-26)

FAQ

What insider transaction did GLDD executive David Johanson report?

GLDD executive David Johanson reported receiving a stock-based compensation award. He acquired 13,179 shares of Great Lakes Dredge & Dock common stock at a stated price of $0.00 per share, reflecting a grant or award rather than a market purchase.

How many GLDD shares does David Johanson hold after this Form 4/A?

After the reported award, David Johanson directly holds 104,063.2594 shares of GLDD common stock. This total includes the 13,179 shares acquired in the transaction, as disclosed in the amended insider ownership information.

What correction does this GLDD Form 4/A make to prior disclosures?

The amended filing corrects an administrative error in a prior Form 4. It changes the reported vesting start date for the related Restricted Stock Units from March 15, 2026, to the correct vesting date beginning on May 8, 2026.

Was the GLDD stock awarded to Johanson a market purchase or compensation grant?

The transaction is described as a grant or award acquisition. Johanson received 13,179 GLDD common shares at a reported price of $0.00 per share, indicating stock-based compensation rather than an open-market purchase.

What is David Johanson’s role at Great Lakes Dredge & Dock (GLDD)?

David Johanson is an officer of Great Lakes Dredge & Dock, serving as Senior Vice President, Project Acquisition & Operations. The reported stock transaction reflects compensation awarded in connection with his executive role at the company.

Does this GLDD Form 4/A indicate any share sales by David Johanson?

The disclosed transaction only shows an acquisition of shares through a grant. There are no reported sales or dispositions; the filing records a stock award that increased Johanson’s direct holdings in GLDD common stock.