Mesa Laboratories, Inc.
A maker of quality-control tools for hospitals, labs, and pharmaceutical companies, Mesa Laboratories builds biological indicators—like its EZTest and Smart-Read lines—that verify sterilization equipment actually kills germs. Founded in Lakewood, Colorado in 1982, it grew from a small instrumentation and calibration shop into a global player through steady acquisitions, including Agena Bioscience and GKE. The name nods to the flat-topped hills common across its home state, a fitting touch for a company rooted in the American West.
Granted 2.5K
Granted 70.8K · Sold 30.0K
Sold 7.0K
Granted 15.8K · Sold 4.7K
Granted 3.5K · Bought 3.5K
Granted 13.8K · Sold 7.1K
Granted 2.5K · Bought 1.3K
Granted 2.5K
Granted 2.5K
Granted 2.1K · Bought 1.3K
Granted 989 · Sold 560
| Insider | Stake change | Holds now | Granted / vested | Bought | Sold |
|---|---|---|---|---|---|
| Sullivan John JamesDirector · 7 transactions | -4.8% | 70.1K | 2.5K | — | — |
| Owens Gary MPresident and CEO · 18 transactions | +106.9% | 64.1K | 70.8K | — | 30.0K |
| Schmieder John BradleyDirector · 3 transactions | -10% | 62.8Kas of Sep 2023 | — | — | 7.0K |
| Sakys JohnCFO · 16 transactions | +78.4% | 19.8K | 15.8K | — | 4.7K |
| Ladiwala Shiraz ShabanaliDirector · 3 transactions | +483.8% | 8.5K | 3.5K | 3.5K | — |
| Archbold Brian DavidSVP Operations · 19 transactions | +183.8% | 6.4K | 13.8K | — | 7.1K |
| Tripeny R TonyDirector · 3 transactions | +236.3% | 5.4K | 2.5K | 1.3K | — |
| Alltoft Jennifer SadieDirector · 2 transactions | +103.3% | 4.9Kas of Aug 2025 | 2.5K | — | — |
| Hall ShannonDirector · 2 transactions | +144.8% | 4.2Kas of Aug 2025 | 2.5K | — | — |
| Capone Mark ChristopherDirector · 3 transactions | — | 3.4K | 2.1K | 1.3K | — |
| Crennen Lyndsey ElizabethCAO · 6 transactions | — | 2.0K | 989 | — | 560 |
Select a row to see that insider’s individual transactions. Sum of the holdings confirmed in the 12 months before this insider's last filing. A Form 4 reports a holding per line — held directly, or through a named trust, partnership or foundation, and in each share class separately — never a person’s total. Lines not restated in that time are left out and shown apart: an active filer restates what they still hold, so a line they did not restate is more often an entity since renamed, whose shares a successor line reports too. An amber marker means some were left out.
Net open-market activity over the last 3 years: -43.3K shares. Grants, option exercises and tax withholding are excluded — they are compensation mechanics, not decisions to buy or sell.