Shanahan Kathleen M 4

4 · Great Lakes Dredge & Dock CORP · Filed Apr 1, 2026

AI-generated summary of this filing

Updated Apr 1, 2026

Great Lakes Dredge (GLDD) Director Kathleen Shanahan Sells 76,375 Shares

What Happened

Kathleen M. Shanahan, a director of Great Lakes Dredge & Dock Corporation (GLDD), had 76,375 common shares converted into cash at $17.00 per share as part of the company’s merger with Saltchuk Resources — generating approximately $1,298,375.
The filing also shows derivative activity: a grant of 1,485 Deferred Stock Units (DSUs) on March 31, 2026 (recorded at $0) and the disposition/cancellation of 10,336 DSUs. Under the merger terms, outstanding DSUs were converted into cash equal to the underlying shares × $17 (10,336 DSUs ≈ $175,712; 1,485 DSUs ≈ $25,245 if converted).

Key Details

Transaction dates: DSU grant and DSU disposition recorded 2026-03-31; common-stock conversion (change in control) effective 2026-04-01.
Price / consideration: Merger consideration = $17.00 per common share (cash, no interest, subject to withholding).
Value: 76,375 shares × $17 ≈ $1,298,375; 10,336 DSUs × $17 ≈ $175,712 (1,485 DSUs × $17 ≈ $25,245).
Shares owned after transaction: No common shares reported after the Effective Time (outstanding common stock was cancelled and converted); DSUs were cancelled/converted to cash.
Notable footnotes: Transactions arose from the Agreement and Plan of Merger (Saltchuk merger). DSUs were granted under the issuer’s Director Deferral Plan and then converted/cancelled at the Effective Time.
Filing timeliness: Report filed 2026-04-01 for a period ending 2026-03-31 — the filing reflects the merger effective date and appears timely.

Context

These are merger-related conversions, not open-market sales or exercises; each share and DSU was converted into a fixed cash payment per the merger agreement. Such filings document the mechanical conversion of equity and deferred awards into cash and do not, by themselves, indicate the insider’s market view.

Form 4Exit

Period: 2026-03-31

Director

Transactions

Disposition from Tender
Common Stock
[F1]
2026-04-01−76,375→ 0 total
Award
Deferred Stock Units
[F2]
2026-03-31+1,485→ 10,336 total
→ Common Stock (1,485 underlying)
Disposition to Issuer
Deferred Stock Units
[F3]
2026-03-31−10,336→ 0 total
Exercise: $17.00→ Common Stock (10,336 underlying)

Footnotes (3)

[F1]Pursuant to the Agreement and Plan of Merger (the "Merger Agreement"), dated February 10, 2026, by and among Saltchuk Resources, Inc. ("Parent"), Huron MergeCo, Inc. ("Merger Sub"), and Great Lakes Dredge & Dock Corporation ("Issuer") on April 1, 2026 (the "Effective Time"), Merger Sub merged with and into Issuer, with Issuer surviving as a wholly owned subsidiary of Parent upon consummation of the transactions contemplated by the Merger Agreement. At the Effective Time, each outstanding share of common stock of the Issuer ("Common Stock") was cancelled and converted into the right to receive $17.00 in cash (the "Merger Consideration"), without interest and subject to any required tax withholdings.
[F2]Deferred Stock Units ("DSUs") granted March 31, 2026 and deferred pursuant to the Issuer's Director Deferral Plan.
[F3]Includes 10,336 DSUs. At the Effective Time, each outstanding award of DSUs was canceled and converted into the right to receive an amount in cash equal to the product of the aggregate number of shares of Common Stock underlying such DSU immediately prior to the Effective Time, multiplied by the Merger Consideration.

Signature

/s/Vivienne R. Schiffer, by Power of Attorney|2026-04-01

1 file