William Marshall Mauney Jr. - 11 May 2026 Form 4 Insider Report for POWELL INDUSTRIES INC (POWL)

Reporting relationship: Vice President, R&D
Issuer ticker: POWL
Reported as of: 11 May 2026
Net transaction value: -$809,218
SEC form: 4
Accepted by SEC: 13 May 2026, 16:14:13 UTC
Prior SEC filing: 22 Dec 2025
Source filing: View source filing
Reporting owner signature: Michael W. Metcalf, Power of Attorney for William Marshall Mauney, Jr.

Key filing fact

William Marshall Mauney Jr. filed Form 4 for POWELL INDUSTRIES INC (POWL) on 13 May 2026.

Key facts

This page summarizes William Marshall Mauney Jr.'s Form 4 filing for POWELL INDUSTRIES INC (POWL).
7 reported transactions and 0 derivative rows are listed below.
Accepted by SEC: 13 May 2026, 16:14.

Change

Previous filing in this sequence was filed on 22 Dec 2025.
Current net transaction value: -$809,218.

Research use

This tells you what this filing adds before you inspect full transaction and derivative tables.
You can trace every row back to the original SEC filing document.

Evidence

Filed on Form 4

Ownership activity is grounded in SEC Form 4 disclosures.

View source filing

Reporting Owners (1)

CIK 0002025220 Primary reporting owner

Mauney William Marshall Jr

Relationship: Vice President, R&D
Address: 8550 MOSLEY ROAD, HOUSTON
Signature: Michael W. Metcalf, Power of Attorney for William Marshall Mauney, Jr.
Signature date: 12 May 2026

Reported non-derivative transactions

Shares, units, or other non-derivative securities reported in this filing.

POWL transaction

Common Stock

Sale

Transaction value: $298,364
Shares: -927
Change %: -6.9%
Price: $321.86
Shares after: 12,426
Date: 11 May 2026
Ownership: Direct
Footnotes: F1, F2, F3

POWL transaction

Common Stock

Sale

Transaction value: $124,562
Shares: -386
Change %: -3.1%
Price: $322.70
Shares after: 12,040
Date: 11 May 2026
Ownership: Direct
Footnotes: F2, F3, F4

POWL transaction

Common Stock

Sale

Transaction value: $56,992
Shares: -176
Change %: -1.5%
Price: $323.82
Shares after: 11,864
Date: 11 May 2026
Ownership: Direct
Footnotes: F2, F3, F5

POWL transaction

Common Stock

Sale

Transaction value: $101,684
Shares: -313
Change %: -2.6%
Price: $324.87
Shares after: 11,551
Date: 11 May 2026
Ownership: Direct
Footnotes: F2, F3, F6

POWL transaction

Common Stock

Sale

Transaction value: $203,079
Shares: -623
Change %: -5.4%
Price: $325.97
Shares after: 10,928
Date: 11 May 2026
Ownership: Direct
Footnotes: F2, F3, F7

POWL transaction

Common Stock

Sale

Transaction value: $21,586
Shares: -66
Change %: -0.6%
Price: $327.06
Shares after: 10,862
Date: 11 May 2026
Ownership: Direct
Footnotes: F2, F3, F8

POWL transaction

Common Stock

Sale

Transaction value: $2,949
Shares: -9
Change %: -0.08%
Price: $327.69
Shares after: 10,853
Date: 11 May 2026
Ownership: Direct
Footnotes: F2, F3, F9

^* marks a reported price that did not pass the local price check.

Additional SEC filing notes

Filing notes and footnotes

Explanation of responses 9 footnotes

Footnote F1

The price reported in Column 4 is an average price; shares were sold in multiple transactions. Reporting range is $321.39-$322.39, inclusive. Reporting person, upon request, will provide Powell Industries, Inc. or the staff of the Securities & Exchange Commission full information regarding the number of shares sold at each price within the ranges set for in this footnote.

Footnote F2

Includes shares that have a time-based vesting provision.

Footnote F3

The reported number of shares have been adjusted to reflect the impact of the issuer's 3-for-1 forward split of its Common Stock effected on April 2, 2026.

Footnote F4

The price reported in Column 4 is an average price; shares were sold in multiple transactions. Reporting range is $322.43-$323.40, inclusive. Reporting person, upon request, will provide Powell Industries, Inc. or the staff of the Securities & Exchange Commission full information regarding the number of shares sold at each price within the ranges set for in this footnote.

Footnote F5

The price reported in Column 4 is an average price; shares were sold in multiple transactions. Reporting range is $323.44-$324.39, inclusive. Reporting person, upon request, will provide Powell Industries, Inc. or the staff of the Securities & Exchange Commission full information regarding the number of shares sold at each price within the ranges set for in this footnote.

Footnote F6

The price reported in Column 4 is an average price; shares were sold in multiple transactions. Reporting range is $324.47-$325.10, inclusive. Reporting person, upon request, will provide Powell Industries, Inc. or the staff of the Securities & Exchange Commission full information regarding the number of shares sold at each price within the ranges set for in this footnote.

Footnote F7

The price reported in Column 4 is an average price; shares were sold in multiple transactions. Reporting range is $325.44-$326.54, inclusive. Reporting person, upon request, will provide Powell Industries, Inc. or the staff of the Securities & Exchange Commission full information regarding the number of shares sold at each price within the ranges set for in this footnote.

Footnote F8

The price reported in Column 4 is an average price; shares were sold in multiple transactions. Reporting range is $326.66-$327.45, inclusive. Reporting person, upon request, will provide Powell Industries, Inc. or the staff of the Securities & Exchange Commission full information regarding the number of shares sold at each price within the ranges set for in this footnote.

Footnote F9

The price reported in Column 4 is an average price; shares were sold in multiple transactions. Reporting range is $327.68-$327.71, inclusive. Reporting person, upon request, will provide Powell Industries, Inc. or the staff of the Securities & Exchange Commission full information regarding the number of shares sold at each price within the ranges set for in this footnote.