1 unchanged sentence
Insider Adoption or Termination of Trading Arrangements
−Removed: On November 26, 2025 , Brett A.
−Removed: Cope , President and Chief Executive Officer , adopted a “Rule 10b5-1 trading arrangement,” as the term is defined in Item 408(a) of Regulation S-K, for the sale of up to 8,900 shares of the Company’s common stock, subject to certain conditions, from March 12, 2026 through December 31, 2026 .
−Removed: On December 2, 2025 , Michael W.
−Removed: Metcalf , Executive Vice President, Chief Financial and Principal Accounting Officer , adopted a “Rule 10b5-1 trading arrangement,” as the term is defined in Item 408(a) of Regulation S-K, for the sale of up to 4,500 shares of the Company’s common stock, subject to certain conditions, from March 31, 2026 through December 31, 2026 .
+Added: On February 11, 2026 , Richard E.
+Added: Williams , Director of the Company , adopted a “Rule 10b5-1 trading arrangement,” as the term is defined in Item 408(a) of Regulation S-K, for the sale of up to 7,500 shares of the Company’s common stock as adjusted for the Stock Split, subject to certain conditions, from May 14, 2026 through December 31, 2026 .
+Added: On February 27, 2026 , Mohit Singh , Director of the Company , adopted a “Rule 10b5-1 trading arrangement,” as the term is defined in Item 408(a) of Regulation S-K, for the sale of up to 1,350 shares of the Company’s common stock as adjusted for the Stock Split, subject to certain conditions, from May 28, 2026 through February 26, 2027 .
Number Description of Exhibits
3 unchanged sentences
(filed as Exhibit 3.1 to our Form 8-K filed February 24, 2025, and incorporated herein by reference).
+Added: 3.3 — Certificate of Amendment to Amended and Restated Certificate of Incorporation of Powell Industries, Inc.
+Added: filed with the Secretary of the State of Delaware on March 31, 2026 (filed as Exhibit 3.1 to our Form 8-K filed March 31, 2026, and incorporated herein by reference).
*31.1 — Certification of Chief Executive Officer pursuant to Rule 13a-14(a)/15d-14(a).
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Section 1350, as Adopted Pursuant to Section 906 of the Sarbanes-Oxley Act of 2002.
−Removed: *§10.1 — Amended Form of Restricted Stock Unit Award Agreement under 2014 Equity Incentive Plan.
−Removed: *§10.2 — Amended Form of Performance Unit Award Agreement under 2014 Equity Incentive Plan.
−Removed: *101 — The following financial statements from the Company’s Quarterly Report on Form 10-Q for the quarter ended December 31, 2025, formatted in Inline XBRL:
+Added: *101 — The following financial statements from the Company’s Quarterly Report on Form 10-Q for the quarter ended March 31, 2026, formatted in Inline XBRL:
(i) Condensed Consolidated Balance Sheets (Unaudited);
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and (vi) Notes to Condensed Consolidated Financial Statements (Unaudited), tagged as blocks of text and including detailed tags.
−Removed: *104 — The cover page from the Company’s Quarterly Report on Form 10-Q for the quarter ended December 31, 2025, formatted in Inline XBRL (included as Exhibit 101).
+Added: *104 — The cover page from the Company’s Quarterly Report on Form 10-Q for the quarter ended March 31, 2026, formatted in Inline XBRL (included as Exhibit 101).
§ Management contracts and compensatory plans or arrangements
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POWELL INDUSTRIES, INC.
−Removed: February 4, 2026 By:
+Added: May 5, 2026 By:
President and Chief Executive Officer
(Principal Executive Officer)
−Removed: February 4, 2026 By:
+Added: May 5, 2026 By:
/s/ Michael W.
3 unchanged sentences
Compared sentence by sentence after normalising whitespace, quotation marks, case and digits, so re-formatting and restated figures do not read as changed language. Wording changes appear as one removal and one addition. The current filing and the prior one are authoritative.