Donaldson Company, Inc.
A maker of filters and filtration systems used everywhere from tractor engines to hospital labs. Its products — like PowerCore® air filters, dust collectors, and bioprocessing gear — keep construction, farming, aerospace, and life-sciences equipment running clean, sold to manufacturers and as replacement parts. The company began in 1915, when salesman Frank Donaldson rigged a tractor air cleaner out of a wire cage, eiderdown cloth, and an eight-foot pipe after watching a farmer's machine choke on Utah dust; his boss dismissed the idea, so he started his own company. That first makeshift "Twister" filter grew into one of the world's largest filtration businesses.
Granted 525.1K · Sold 215.5K
Granted 3.3K
Granted 134.6K · Sold 101.5K
Granted 72.0K · Sold 39.5K
Granted 60.8K
Granted 220.9K · Sold 182.2K
Granted 98.6K · Sold 86.7K
Granted 62.1K · Sold 36.8K
Granted 19.8K · Sold 5.4K
Granted 5.1K
Granted 64.6K · Sold 58.5K
Granted 86.3K · Sold 74.7K
Granted 62.7K · Sold 45.5K
Granted 59.0K · Sold 45.9K
Granted 8.0K
Granted 12.1K · Bought 3.2K
Granted 32.2K · Sold 26.3K
Granted 1.7K · Sold 30.0K
Granted 7.7K
Granted 5.9K
Granted 1.2K
Granted 2.8K
Granted 2.0K · Sold 2.0K
Granted 4.0K · Sold 566
Granted 1.0K
| Insider | Stake change | Holds now | Granted / vested | Bought | Sold |
|---|---|---|---|---|---|
| Carpenter Tod E.Chairman, President and CEO, Director · 28 transactions | +62.3% | 309.8K | 525.1K | — | 215.5K |
| Wiehoff JohnDirector · 6 transactions | +7.7% | 63.9Kas of Oct 2022 | 3.3K | — | — |
| Scalf Thomas RPresident · 25 transactions | +86.5% | 56.9Kas of Mar 2025 | 134.6K | — | 101.5K |
| Becker Amy CChief Legal Officer · 18 transactions | +63.6% | 56.0K | 72.0K | — | 39.5K |
| Lewis Richard BrentPresident · 18 transactions | +274% | 46.5K | 60.8K | — | — |
| Robinson Scott J.Chief Financial Officer · 17 transactions | +80% | 45.1Kas of Oct 2024 | 220.9K | — | 182.2K |
| Rajendra Ajita GDirector · 23 transactions | +45.6% | 45.0K | 98.6K | — | 86.7K |
| Briseno GuillermoPresident · 13 transactions | — | 41.3K | 62.1K | — | 36.8K |
| Dahlgren Andrew CPresident · 12 transactions | — | 39.6K | 19.8K | — | 5.4K |
| Spethmann Jeffrey ESenior Vice President · 2 transactions | +6.3% | 32.1Kas of Sep 2022 | 5.1K | — | — |
| Oberton Willard DDirector · 42 transactions | -7.4% | 29.8Kas of Jul 2025 | 64.6K | — | 58.5K |
| Owens JamesDirector · 42 transactions | +198.8% | 29.2K | 86.3K | — | 74.7K |
| Kramer Sheila G.Chief Human Resources Officer · 12 transactions | +99.2% | 28.5Kas of Oct 2024 | 62.7K | — | 45.5K |
| Rautio Trudy A.Director · 31 transactions | +66.3% | 27.7K | 59.0K | — | 45.9K |
| Cruz PilarDirector · 19 transactions | +112.1% | 16.7K | 8.0K | — | — |
| Hilger Christopher M.Director · 25 transactions | — | 15.8K | 12.1K | 3.2K | — |
| Milroy Douglas A.Director · 8 transactions | +71% | 15.1K | 32.2K | — | 26.3K |
| Vermeersch WimVice President · 5 transactions | -56.9% | 14.7Kas of Sep 2022 | 1.7K | — | 30.0K |
| Smiley Jacinth CDirector · 11 transactions | — | 7.9K | 7.7K | — | — |
| Olson Richard MDirector · 5 transactions | — | 6.1K | 5.9K | — | — |
| Hoffman Michael JDirector · 1 transaction | -94% | 4.7Kas of Jan 2022 | 1.2K | — | — |
| Cebulla Andrew J.Corporate Controller · 4 transactions | — | 4.3K | 2.8K | — | — |
| Keller Peter JosephCorporate Controller · 3 transactions | +5.6% | 2.3Kas of Dec 2021 | 2.0K | — | 2.0K |
| Pogalz Bradley J.Chief Financial Officer · 4 transactions | — | 2.2K | 4.0K | — | 566 |
| Shine Daniel PDirector · 2 transactions | — | 1.0K | 1.0K | — | — |
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 5 years: -948.0K shares. Grants, option exercises and tax withholding are excluded — they are compensation mechanics, not decisions to buy or sell.