XERS's three largest insider shareholders as of September 17, 2026 are Paul R Edick (Director, 3.79Mn shares), John Patrick Jr Shannon (Director, 2.90Mn shares), Kevin Mcculloch (Officer, 1.64Mn shares).
| # | Insider | Position | Direct | Indirect | Total | Share of Insiders | Last Filed |
|---|---|---|---|---|---|---|---|
| 1 | Paul R Edick | Director, Officer | 3,788,064 | 0 | 3,788,064 | 26.8% | 31 Jan, 2024 |
| 2 | John Patrick Jr Shannon | Director, Officer | 2,898,933 | 0 | 2,898,933 | 20.5% | 21 Aug, 2026 |
| 3 | Kevin Mcculloch | Officer | 1,639,208 | 0 | 1,639,208 | 11.6% | 01 Sep, 2026 |
| 4 | Steven Pieper | Officer | 1,356,053 | 0 | 1,356,053 | 9.6% | 01 Sep, 2026 |
| 5 | Beth Hecht | Officer | 1,127,796 | 0 | 1,127,796 | 8.0% | 01 Sep, 2026 |
| 6 | Steven Prestrelski | Chief Scientific Officer | 719,780 | 0 | 719,780 | 5.1% | 01 Feb, 2023 |
| 7 | John Johnson | Director | 707,276 | 0 | 707,276 | 5.0% | 05 Jun, 2026 |
| 8 | Anh Tu Nguyen | Officer | 395,023 | 0 | 395,023 | 2.8% | 25 Feb, 2026 |
| 9 | Kenneth Erland Johnson | Officer | 320,446 | 0 | 320,446 | 2.3% | 03 Feb, 2025 |
| 10 | Garheng Kong | Director | 238,337 | 0 | 238,337 | 1.7% | 05 Jun, 2026 |
| 11 | Jeffrey W Sherman | Director | 219,188 | 0 | 219,188 | 1.6% | 29 Aug, 2025 |
| 12 | Marla Persky | Director | 150,693 | 0 | 150,693 | 1.1% | 05 Jun, 2026 |
| 13 | Barbara-Jean Anne Bormann-Kennedy | Director | 150,693 | 0 | 150,693 | 1.1% | 05 Jun, 2026 |
| 14 | Ricki Louise Fairley | Director | 135,000 | 0 | 135,000 | 1.0% | 05 Jun, 2024 |
| 15 | Dawn Halkuff | Director | 119,193 | 0 | 119,193 | 0.8% | 05 Jun, 2026 |
| 16 | James Aloysius Brady | Director | 113,359 | 0 | 113,359 | 0.8% | 05 Jun, 2026 |
| 17 | Nerissa Kreher | Director | 33,582 | 0 | 33,582 | 0.2% | 02 Jul, 2026 |
| 18 | John P. Schmid | Director | 0 | 25,200 | 25,200 | 0.2% | 13 Aug, 2024 |
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 |
|---|---|---|---|---|---|---|---|---|
| 01 Sep, 2026 | Kevin Mcculloch | Officer | Disposed S | 15,000 | $8.49 | $127.31K | 1,639,208 | Direct |
| 01 Sep, 2026 | Beth Hecht | Officer | Disposed S | 16,666 | $8.49 | $141.43K | 1,127,796 | Direct |
| 01 Sep, 2026 | Steven Pieper | Officer | Disposed S | 5,000 | $8.50 | $42.50K | 1,356,053 | Direct |
| 01 Aug, 2026 | John Patrick Jr Shannon | Director, Officer | Disposed F | 36,645 | $8.08 | $296.09K | 2,898,933 | Direct |
| 01 Aug, 2026 | Kevin Mcculloch | Officer | Disposed F | 21,918 | $8.08 | $177.10K | 1,654,208 | Direct |
| 12 Aug, 2026 | Steven Pieper | Officer | Disposed S | 5,000 | $8.50 | $42.50K | 1,361,053 | Direct |
| 03 Aug, 2026 | Beth Hecht | Officer | Disposed S | 16,666 | $8.01 | $133.55K | 1,144,462 | Direct |
| 03 Aug, 2026 | Kevin Mcculloch | Officer | Disposed S | 15,000 | $8.02 | $120.24K | 1,676,126 | Direct |
| 06 Jul, 2026 | Steven Pieper | Officer | Disposed S | 17,400 | $8.50 | $147.90K | 1,393,653 | Direct |
| 07 Jul, 2026 | Steven Pieper | Officer | Disposed S | 27,600 | $8.52 | $235.28K | 1,366,053 | Direct |
| 01 Jul, 2026 | Nerissa Kreher | Director | Acquired A | 33,582 | $0.00 | $0 | 33,582 | Direct |
| 01 Jul, 2026 | Beth Hecht | Officer | Disposed S | 16,666 | $8.03 | $133.86K | 1,161,128 | Direct |
| 01 Jul, 2026 | Kevin Mcculloch | Officer | Disposed S | 90,000 | $8.03 | $722.51K | 1,691,126 | Direct |
| 01 Jul, 2026 | Nerissa Kreher | Director | Acquired A | 37,910 | $8.00 | $303.28K | 37,910 | Direct |
| 04 Jun, 2026 | Barbara-Jean Anne Bormann-Kennedy | Director | Disposed S | 16,000 | $6.09 | $97.51K | 126,500 | Direct |
| 04 Jun, 2026 | John Johnson | Director | Disposed S | 15,000 | $6.09 | $91.42K | 683,083 | Direct |
| 03 Jun, 2026 | Marla Persky | Director | Disposed S | 15,500 | $5.90 | $91.43K | 126,500 | Direct |
| 04 Jun, 2026 | Dawn Halkuff | Director | Disposed S | 20,000 | $6.09 | $121.89K | 95,000 | Direct |
| 04 Jun, 2026 | Garheng Kong | Director | Acquired A | 24,193 | $0.00 | $0 | 238,337 | Direct |
| 04 Jun, 2026 | James Aloysius Brady | Director | Acquired A | 24,193 | $0.00 | $0 | 113,359 | Direct |