A. Mark Zeffiro - 19 Oct 2026 Form 4 Insider Report for Atkore Inc. (ATKR)

Footnote F1

On October 19, 2026 (the "Closing Date"), pursuant to the Agreement and Plan of Merger, dated August 2, 2026 (the "Merger Agreement"), by and among Atkore Inc. ("Atkore" or the "Company"), Prysmian S.p.A., a company organized under the laws of the Republic of Italy ("Buyer"), Trinity Merger Sub, Inc., a Delaware corporation and a wholly owned subsidiary of Buyer ("Merger Sub"), and, solely as provided in certain sections of the Merger Agreement, Prysmian Cables and Systems USA, LLC, a Delaware limited liability company, Merger Sub merged with and into the Company (the "Merger"), with the Company surviving the Merger as a wholly owned subsidiary of Buyer (the "Surviving Corporation").

Footnote F2

At the effective time of the Merger (the "Effective Time"), each share of common stock of Atkore, par value $0.01 per share ("Common Stock") issued and outstanding immediately prior to the Effective Time, was (except as otherwise provided in the Merger Agreement) converted into the right to receive $95.00 in cash, without interest (the "Merger Consideration").

Footnote F3

Includes deferred stock units ("DSUs") and any amounts accrued for dividend equivalent units thereon. Under the Merger Agreement, at the Effective Time, each outstanding DSU was canceled and converted into the right to receive a cash payment from the Surviving Corporation equal to the product of (A) the Merger Consideration and (B) the total number of shares of Common Stock underlying such DSU.

Footnote F4

Includes restricted stock units ("RSUs") and any amounts accrued for dividend equivalent units thereon. Under the Merger Agreement, at the Effective Time, each outstanding RSU, whether vested or unvested, was deemed fully vested and canceled and converted into the right to receive a cash payment from the Surviving Corporation equal to the product of (A) the Merger Consideration and (B) the total number of shares of Common Stock underlying such RSU.