As of September 29, 2026, the three largest insider holders of ATRO are Peter J Gundermann (President/Ceo, 916.29K shares), Peter J Gundermann (President/Ceo, 743.49K shares), Mark Peabody (Executive Vp Pres Aerospace, 232.61K shares).
| # | Insider | Position | Direct | Indirect | Total | Share of Insiders | Last Filed |
|---|---|---|---|---|---|---|---|
| 1 | Peter J Gundermann | President/Ceo | 1,805,866 | 0 | 1,805,866 | 46.4% | 17 Jun, 2026 |
| 2 | Robert T Brady | Director | 672,236 | 0 | 672,236 | 17.3% | 17 Jun, 2026 |
| 3 | Mark Peabody | Executive Vp Pres Aerospace | 519,382 | 0 | 519,382 | 13.4% | 19 Aug, 2026 |
| 4 | Robert S Keane | Director | 27,900 | 249,838 | 277,738 | 7.1% | 26 Aug, 2026 |
| 5 | David C Burney | Vp Finance, Cfo | 112,743 | 0 | 112,743 | 2.9% | 02 Oct, 2024 |
| 6 | James Mulato | Other | 67,286 | 0 | 67,286 | 1.7% | 17 Jun, 2026 |
| 7 | James S Kramer | Vp Luminescent Systems, Inc. | 63,056 | 0 | 63,056 | 1.6% | 02 Oct, 2024 |
| 8 | Jeffry D Frisby | Director | 59,987 | 0 | 59,987 | 1.5% | 18 Sep, 2026 |
| 9 | Warren C Johnson | Director | 59,707 | 0 | 59,707 | 1.5% | 17 Jun, 2026 |
| 10 | Nancy L Hedges | Principal Accounting Officer | 56,945 | 0 | 56,945 | 1.5% | 17 Jun, 2026 |
| 11 | Neil Y. Kim | Director | 52,867 | 0 | 52,867 | 1.4% | 17 Jun, 2026 |
| 12 | Mark J Moran | Director | 52,867 | 0 | 52,867 | 1.4% | 17 Jun, 2026 |
| 13 | Linda O'Brien | Director | 25,646 | 240 | 25,886 | 0.7% | 17 Jun, 2026 |
| 14 | Tonit M Calaway | Director | 15,730 | 0 | 15,730 | 0.4% | 31 May, 2022 |
| 15 | Raymond W Boushie | Director | 14,862 | 0 | 14,862 | 0.4% | 24 Aug, 2022 |
| 16 | Michael C Kuehn | Executive Vice President | 13,210 | 0 | 13,210 | 0.3% | 14 May, 2024 |
| 17 | Julie M Davis | Secretary | 9,722 | 0 | 9,722 | 0.2% | 17 Jun, 2026 |
| 18 | Fay West | Director | 9,105 | 0 | 9,105 | 0.2% | 17 Jun, 2026 |
Each row is that insider’s most recently reported position, from Form 4 filings over the last 60 months — which is why this total does not tie to the quarterly series above, where a quarter counts only the insiders who filed in it. Shares held through a fund or institutional portfolio are counted on the institutional ownership page instead.
| Date | Insider | Position | Transaction | Shares | Price | Value | Shares Held After | Ownership |
|---|---|---|---|---|---|---|---|---|
| 16 Sep, 2026 | Jeffry D Frisby | Director | Acquired M | 4,000 | $23.75 | $95.00K | 49,056 | Direct |
| 16 Sep, 2026 | Jeffry D Frisby | Director | Acquired M | 1,520 | $23.75 | $36.10K | 10,931 | Direct |
| 16 Sep, 2026 | Jeffry D Frisby | Director | Disposed M | 4,000 | $23.75 | $95.00K | 0 | Direct |
| 16 Sep, 2026 | Jeffry D Frisby | Director | Disposed M | 1,520 | $23.75 | $36.10K | 0 | Direct |
| 25 Aug, 2026 | Robert S Keane | Director | Acquired C | 76,000 | $0.00 | $0 | 76,000 | Indirect |
| 25 Aug, 2026 | Robert S Keane | Director | Disposed C | 76,000 | $0.00 | $0 | 173,838 | Indirect |
| 17 Aug, 2026 | Jeffry D Frisby | Director | Disposed G | 2,000 | $0.00 | $0 | 45,056 | Direct |
| 18 Aug, 2026 | Mark Peabody | Executive Vp Pres Aerospace | Disposed G | 150 | $0.00 | $0 | 62,233 | Direct |
| 15 Jun, 2026 | Mark Peabody | Executive Vp Pres Aerospace | Acquired J | 49,165 | $0.00 | $0 | 232,610 | Direct |
| 15 Jun, 2026 | Nancy L Hedges | Principal Accounting Officer | Acquired J | 6,666 | $0.00 | $0 | 7,953 | Direct |
| 15 Jun, 2026 | Julie M Davis | Secretary | Acquired J | 1,620 | $0.00 | $0 | 2,256 | Direct |
| 15 Jun, 2026 | Neil Y. Kim | Director | Acquired J | 8,811 | $0.00 | $0 | 8,811 | Direct |
| 15 Jun, 2026 | Robert T Brady | Director | Acquired J | 53,085 | $0.00 | $0 | 229,451 | Direct |
| 15 Jun, 2026 | James Mulato | Other | Acquired J | 7,645 | $0.00 | $0 | 10,098 | Direct |
| 15 Jun, 2026 | Fay West | Director | Acquired J | 1,517 | $0.00 | $0 | 1,517 | Direct |
| 15 Jun, 2026 | Robert S Keane | Director | Acquired J | 2,786 | $0.00 | $0 | 2,786 | Direct |
| 15 Jun, 2026 | Jeffry D Frisby | Director | Acquired J | 9,411 | $0.00 | $0 | 9,411 | Direct |
| 15 Jun, 2026 | Warren C Johnson | Director | Acquired J | 9,951 | $0.00 | $0 | 9,951 | Direct |
| 15 Jun, 2026 | Peter J Gundermann | President/Ceo | Acquired J | 168,375 | $0.00 | $0 | 916,286 | Direct |
| 15 Jun, 2026 | Linda O'Brien | Director | Acquired J | 4,274 | $0.00 | $0 | 4,274 | Direct |