As of September 09, 2026, the three largest insider holders of MASS are Investment Company, Inc. Awm (TenPercentOwner, 4.89Mn shares), Investment Company, Inc. Awm (TenPercentOwner, 4.88Mn shares), Investment Company, Inc. Awm (TenPercentOwner, 4.78Mn shares).
| # | Insider | Position | Direct | Indirect | Total | Share of Insiders | Last Filed |
|---|---|---|---|---|---|---|---|
| 1 | Investment Company, Inc. Awm | TenPercentOwner | 0 | 9,667,264 | 9,667,264 | 71.7% | 24 Aug, 2026 |
| 2 | Christopher D. Brown | Chief Product Officer | 1,667,934 | 0 | 1,667,934 | 12.4% | 04 Sep, 2026 |
| 3 | Kevin J. Knopp | President And Ceo | 923,816 | 0 | 923,816 | 6.8% | 17 Aug, 2026 |
| 4 | E Kevin Hrusovsky | Director | 485,961 | 0 | 485,961 | 3.6% | 12 Jun, 2026 |
| 5 | Joseph H. Iv Griffith | Chief Financial Officer | 214,934 | 0 | 214,934 | 1.6% | 27 Aug, 2026 |
| 6 | Mark Spoto | Director | 129,769 | 0 | 129,769 | 1.0% | 12 Jun, 2026 |
| 7 | Trent A. Basarsky | Vp, Corporate Development | 115,000 | 0 | 115,000 | 0.9% | 28 Apr, 2022 |
| 8 | John Kenneweg | Svp, Sales Product Marketing | 57,784 | 0 | 57,784 | 0.4% | 11 May, 2026 |
| 9 | Fenel M Eloi | Director | 48,570 | 0 | 48,570 | 0.4% | 12 Jun, 2026 |
| 10 | Kevin J. Mccallion | Svp, Products And Production | 44,925 | 0 | 44,925 | 0.3% | 14 Apr, 2026 |
| 11 | Keith Crandell | Director | 40,753 | 0 | 40,753 | 0.3% | 12 Jun, 2026 |
| 12 | Jeffrey P. George | Director | 34,487 | 0 | 34,487 | 0.3% | 13 Jun, 2025 |
| 13 | Michele M. Leonhart | Director | 27,054 | 0 | 27,054 | 0.2% | 25 Jun, 2026 |
| 14 | Marcia Eisenberg | Director | 25,957 | 0 | 25,957 | 0.2% | 13 Jun, 2025 |
| 15 | Brandi C Vann | Director | 5,192 | 0 | 5,192 | 0.0% | 03 Aug, 2026 |
| 16 | Maura Fitzpatrick | Vp, Product Management Mktg | 2,834 | 0 | 2,834 | 0.0% | 03 Feb, 2023 |
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 |
|---|---|---|---|---|---|---|---|---|
| 02 Sep, 2026 | Christopher D. Brown | Director | Disposed S | 30,000 | $10.58 | $317.40K | 775,559 | Direct |
| 25 Aug, 2026 | Joseph H. Iv Griffith | Chief Financial Officer | Disposed S | 11,459 | $10.95 | $125.48K | 121,497 | Direct |
| 13 Aug, 2026 | Kevin J. Knopp | President And Ceo | Disposed S | 7,622 | $10.06 | $76.68K | 575,968 | Direct |
| 17 Aug, 2026 | Kevin J. Knopp | President And Ceo | Disposed S | 20,000 | $10.35 | $207.00K | 555,968 | Direct |
| 10 Aug, 2026 | Kevin J. Knopp | President And Ceo | Disposed S | 348 | $9.06 | $3.15K | 732,255 | Direct |
| 10 Aug, 2026 | Christopher D. Brown | Director | Disposed S | 9,442 | $9.03 | $85.26K | 813,917 | Direct |
| 11 Aug, 2026 | Kevin J. Knopp | President And Ceo | Disposed S | 115,748 | $9.83 | $1.14Mn | 616,507 | Direct |
| 11 Aug, 2026 | Christopher D. Brown | Director | Disposed S | 8,358 | $9.23 | $77.14K | 805,559 | Direct |
| 11 Aug, 2026 | Kevin J. Knopp | President And Ceo | Disposed S | 30,170 | $10.16 | $306.53K | 586,337 | Direct |
| 12 Aug, 2026 | Kevin J. Knopp | President And Ceo | Disposed S | 2,747 | $10.07 | $27.66K | 583,590 | Direct |
| 05 Aug, 2026 | Christopher D. Brown | Director | Disposed S | 20,000 | $8.49 | $169.80K | 823,359 | Direct |
| 04 Aug, 2026 | Investment Company, Inc. Awm | TenPercentOwner | Disposed S | 50,000 | $8.36 | $417.77K | 4,829,773 | Indirect |
| 01 Aug, 2026 | Brandi C Vann | Director | Acquired M | 5,192 | — | — | 5,192 | Direct |
| 01 Aug, 2026 | Brandi C Vann | Director | Disposed M | 5,192 | $0.00 | $0 | 10,385 | Direct |
| 02 Jul, 2026 | Christopher D. Brown | Director | Disposed S | 2,200 | $9.02 | $19.84K | 843,359 | Direct |
| 02 Jul, 2026 | Kevin J. Knopp | President And Ceo | Disposed S | 222 | $9.07 | $2.01K | 732,603 | Direct |
| 30 Jun, 2026 | Christopher D. Brown | Director | Disposed S | 20,000 | $8.84 | $176.80K | 845,559 | Direct |
| 26 Jun, 2026 | Kevin J. Knopp | President And Ceo | Disposed S | 2,798 | $9.09 | $25.43K | 732,825 | Direct |
| 23 Jun, 2026 | Kevin J. Knopp | President And Ceo | Disposed S | 3,422 | $9.06 | $31.00K | 792,546 | Direct |
| 23 Jun, 2026 | Christopher D. Brown | Director | Disposed S | 9,900 | $9.04 | $89.50K | 865,559 | Direct |