Great Lakes Dredge (GLDD) adds CEO email as exhibit amid $17.00 takeover

Rhea-AI Filing Summary

Great Lakes Dredge & Dock Corporation files Amendment No. 1 to its Schedule 14D-9 to supplement its recommendation/solicitation statement in connection with the cash tender offer and merger agreement under which Huron MergeCo, Inc. (a Saltchuk affiliate) is offering $17.00 per share in cash for each outstanding share of the Company. This Amendment adds an exhibit: an employee email from CEO Lasse Petterson dated March 13, 2026. The remainder of the Schedule 14D-9 is incorporated by reference.

Insights

M&A Counsel

Amendment adds a CEO employee communication as an exhibit to the recommendation statement.

The filing supplements the Schedule 14D-9 tied to the $17.00 per share cash offer and merger agreement dated February 10, 2026. Adding the CEO email as an exhibit is procedural and documents internal communications to shareholders and employees.

Key dependencies include any further amendments to the Offer to Purchase or Schedule TO; timing and cash‑flow treatment of the transaction are described in the Offer materials.

Corporate Governance Analyst

Supplemental exhibit may provide tone and guidance from management to stakeholders.

The exhibit is an email from the CEO to employees dated March 13, 2026, which can clarify management stance on the Offer and internal messaging. Such exhibits often inform shareholder communications but do not change deal economics.

Material impact depends on the email content; further filings or disclosures would be needed to assess any change in recommendation or shareholder action.

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 14D-9

(RULE 14d-101)

SOLICITATION/RECOMMENDATION STATEMENT

UNDER SECTION 14(D)(4) OF THE SECURITIES EXCHANGE ACT OF 1934

(Amendment No. 1)

GREAT LAKES DREDGE & DOCK CORPORATION

(Name of Subject Company)

GREAT LAKES DREDGE & DOCK CORPORATION

(Name of Person(s) Filing Statement)

Common Stock, $0.0001 par value per share

(Title of Class of Securities)

390607109

(CUSIP Number of Class of Securities)

Vivienne R. Schiffer

Senior Vice President, Chief Legal Officer,

Chief Compliance Officer and Corporate Secretary

Great Lakes Dredge & Dock Corporation

9811 Katy Freeway, Suite 1200

Houston, Texas 77024

(346) 359-1010

(Name, Address and Telephone Number of Person Authorized to Receive Notices and Communications on Behalf of the Person Filing Statement)

With copies to:

 John P. Kelsh

Scott R. Williams

Leigh B. Rorick

Sidley Austin LLP

One South Dearborn

Chicago, Illinois 60603

(312) 853-7000

☐ Check the box if the filing relates solely to preliminary communications made before the commencement of a tender offer.

This Amendment No. 1 (this “Amendment”) to Schedule 14D-9 amends and supplements the Solicitation/Recommendation Statement on Schedule 14D-9 previously filed by Great Lakes Dredge & Dock Corporation, a Delaware corporation (the “Company”), with the U.S. Securities and Exchange Commission (the “SEC”) on March 4, 2026 (as amended or supplemented from time to time, the “Schedule 14D-9”), with respect to the cash tender offer made by Huron MergeCo., Inc., a Delaware corporation (“Purchaser”) and wholly owned subsidiary of Saltchuk Resources, Inc., a Washington corporation (“Parent”), to purchase all of the Company’s issued and outstanding shares of Common Stock, par value $0.0001 per share (the “Shares”), pursuant to the Agreement and Plan of Merger, dated as of February 10, 2026, by and among Parent, Purchaser and the Company (as it may be amended or supplemented from time to time, the “Merger Agreement”), at a purchase price of $17.00 per Share, net to the seller thereof in cash, without interest, subject to any required tax withholding (such consideration as it may be amended from time to time pursuant to the terms of the Merger Agreement), upon the terms and subject to the conditions set forth in the Offer to Purchase, dated March 4, 2026 (together with any amendments or supplements thereto, the “Offer to Purchase”), and in the related Letter of Transmittal (together with any amendments or supplements thereto, the “Letter of Transmittal,” which, together with the Offer to Purchase and other related materials, constitutes the “Offer”). The Offer is described in a Tender Offer Statement on Schedule TO, as amended or supplemented from time to time, filed by Parent and Purchaser with the SEC on March 4, 2026. The Offer to Purchase and the Letter of Transmittal have been filed as Exhibits (a)(1)(i) and (a)(1)(ii) to the Schedule 14D-9, respectively, as each may be amended or supplemented from time to time.

Capitalized terms used in this Amendment but not defined herein shall have the respective meanings given to such terms in the Schedule 14D-9. The information set forth in the Schedule 14D-9 remains unchanged and is incorporated herein by reference, except that such information is hereby amended or supplemented to the extent specifically provided herein.

This Amendment should be read in conjunction with the rest of the Schedule 14D-9, as amended, which we urge you to read in its entirety.

ITEM 9. EXHIBITS

Item 9 of the Schedule 14D-9 is hereby amended and supplemented by adding the following exhibit:

Exhibit No.		Description
(a)(5)(vi)		Email from Lasse Petterson, the Chief Executive Officer of the Company, sent to the Company employees, dated March 13, 2026.

SIGNATURE

After due 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.

GREAT LAKES DREDGE & DOCK CORPORATION
By:		/s/ Vivienne R. Schiffer
Name:		Vivienne R. Schiffer
Title:		Senior Vice President, Chief Legal Officer, Chief Compliance Officer and Corporate Secretary

Date: March 13, 2026

FAQ

What does Great Lakes Dredge & Dock (GLDD) say about the cash offer?

The company supplements its Schedule 14D-9 regarding the cash offer of $17.00 per share made by Huron MergeCo, Inc.; the Merger Agreement dated February 10, 2026 governs the transaction. The Schedule 14D-9 and Offer to Purchase contain the full terms and conditions.

What is included in Amendment No. 1 to the Schedule 14D-9?

Amendment No. 1 adds an exhibit consisting of an email from CEO Lasse Petterson dated March 13, 2026. The filing states the rest of the Schedule 14D-9 remains incorporated by reference and unchanged except as supplemented.

Who is offering to buy GLDD shares and at what price?

The buyer is Huron MergeCo, Inc., a wholly owned subsidiary of Saltchuk Resources, Inc., offering $17.00 per share in cash for each outstanding share under the Merger Agreement and related Offer to Purchase.

Does Amendment No. 1 change the terms or price of the Offer?

The Amendment states it supplements the Schedule 14D-9 by adding an exhibit and that the information in the Schedule 14D-9 remains unchanged except as supplemented; it does not state any change to the $17.00 per share price.

Where can shareholders find the Offer materials referenced in the filing?

The Offer to Purchase and Letter of Transmittal are filed as exhibits to the Schedule 14D-9 and the related Schedule TO filed on March 4, 2026; those exhibits contain the full instructions and terms for tendering shares.