Mesa Laboratories Inc /Co/ (MLAB) Insider Ownership

Historic Ownership Trends

Data spanning the past 90 days through December 20, 2025 reveals that Mesa Laboratories's three principal insider shareholders consist of Director John Bradley Schmieder (82.12K shares), Director John James Sullivan (70.06K shares), President And CEO Gary M Owens (64.14K shares).

Top Direct Holders

Insider ownership data is derived from the last 60 months of Form 4 SEC filings.
Holder Position Shares Report Date
John Bradley Schmieder 82,120 19 Sep, 2023
John James Sullivan 70,062 05 Dec, 2025
Gary M Owens President And CEO 64,135 28 Oct, 2025
Laboratories Inc /Co/ Mesa 29,788 16 Jun, 2022
Evan Guillemin 29,207 02 Sep, 2022
John Sakys Cfo 15,044 25 Jun, 2025
Shiraz Shabanali Ladiwala 5,023 18 Aug, 2025
Jennifer Sadie Alltoft 4,878 18 Aug, 2025
Shannon Hall 4,189 18 Aug, 2025
R Tony Tripeny 4,083 18 Aug, 2025
Gregory Dinoia SVP Commercial 3,634 22 Jun, 2022
David M Kelly 2,600 09 Nov, 2021
Brian David Archbold SVP Operations 2,407 25 Jun, 2025
Mark Christopher Capone 2,128 18 Aug, 2025

* Please note that the shares above only reflect shares from the fund portfolio and the institutional portfolio. Shares from the personal portfolio are excluded from this Institutional Ownership Page. See these insiders' latest transactions here on Insider Page.

Recent Insider Transactions

Detailed insider trading activity based on Form 4 SEC filings.
Download Data
Transaction Date Insider Name Security Class Transaction Type Shares Traded Price Shares Remaining Ownership Code
02 Dec, 2025 John James Sullivan Common Stock D 2,000 $0.00 25,282 D G
27 Oct, 2025 Gary M Owens Common Stock A 11,558 $0.00 64,135 D M
15 Aug, 2025 Shiraz Shabanali Ladiwala Common Stock A 1,949 $0.00 5,023 D M
15 Aug, 2025 Shiraz Shabanali Ladiwala - - 5,023 D
15 Aug, 2025 Shannon Hall Common Stock A 1,404 $0.00 4,189 D M
15 Aug, 2025 Mark Christopher Capone Common Stock A 1,404 $0.00 2,128 D M
15 Aug, 2025 Jennifer Sadie Alltoft Common Stock A 1,404 $0.00 4,878 D M
15 Aug, 2025 R Tony Tripeny Common Stock A 1,404 $0.00 4,083 D M
15 Aug, 2025 John James Sullivan Common Stock A 1,404 $0.00 27,282 D M
21 Jun, 2025 Brian David Archbold Common Stock A 844 $95.82 2,792 D M
21 Jun, 2025 Brian David Archbold - - 2,792 D
21 Jun, 2025 John Sakys Common Stock A 1,036 $95.82 15,498 D M
21 Jun, 2025 Brian David Archbold Common Stock D 385 $95.82 2,407 D F
21 Jun, 2025 John Sakys Common Stock D 454 $95.82 15,044 D F
21 Jun, 2025 Gary M Owens Common Stock A 3,301 $95.82 54,022 D M
21 Jun, 2025 Gary M Owens Common Stock D 1,445 $95.82 52,577 D F
18 Jun, 2025 Brian David Archbold Common Stock A 2,556 $92.99 3,114 D M
18 Jun, 2025 John Sakys Common Stock A 2,840 $92.99 15,705 D M
18 Jun, 2025 Gary M Owens Common Stock A 8,707 $92.99 54,531 D M
18 Jun, 2025 Brian David Archbold Common Stock D 1,166 $92.99 1,948 D F