As of September 09, 2026, the three largest insider holders of BLFS are Partners Master Fund, L.P. Casdin (TenPercentOwner, 13.91Mn shares), Partners Master Fund, L.P. Casdin (TenPercentOwner, 8.74Mn shares), Partners Master Fund, L.P. Casdin (TenPercentOwner, 8.71Mn shares).
| # | Insider | Position | Direct | Indirect | Total | Share of Insiders | Last Filed |
|---|---|---|---|---|---|---|---|
| 1 | Partners Master Fund, L.P. Casdin | TenPercentOwner | 0 | 13,492,324 | 13,492,324 | 84.4% | 21 May, 2026 |
| 2 | Greef Roderick De | President And Ceo | 730,971 | 0 | 730,971 | 4.6% | 22 Jun, 2026 |
| 3 | Aby J. Mathew | Evp Chief Scientific Officer | 388,460 | 0 | 388,460 | 2.4% | 13 Jul, 2026 |
| 4 | Michael Rice | Chief Executive Officer | 347,085 | 0 | 347,085 | 2.2% | 01 Nov, 2023 |
| 5 | Troy Wichterman | Chief Financial Officer | 213,249 | 0 | 213,249 | 1.3% | 13 Jul, 2026 |
| 6 | Todd Berard | Chief Marketing Officer | 162,649 | 0 | 162,649 | 1.0% | 13 Jul, 2026 |
| 7 | Sarah Aebersold | Chief Human Resources Officer | 124,870 | 0 | 124,870 | 0.8% | 23 Mar, 2026 |
| 8 | Garrie Richardson | Chief Revenue Officer | 114,773 | 0 | 114,773 | 0.7% | 18 Sep, 2024 |
| 9 | Karen A. Foster | Chief Quality And Operations | 108,758 | 0 | 108,758 | 0.7% | 31 Mar, 2026 |
| 10 | Geraint Phillips | Svp, Global Operations | 65,998 | 0 | 65,998 | 0.4% | 12 Mar, 2024 |
| 11 | Sean Werner | Chief Technology Officer | 47,556 | 0 | 47,556 | 0.3% | 21 Jul, 2026 |
| 12 | Timothy L. Moore | Director | 44,943 | 0 | 44,943 | 0.3% | 26 Feb, 2026 |
| 13 | Joseph C Schick | Director | 43,953 | 0 | 43,953 | 0.3% | 12 Mar, 2024 |
| 14 | Marcus Schulz | Chief Revenue Officer | 42,097 | 0 | 42,097 | 0.3% | 29 Aug, 2023 |
| 15 | Amy Duross | Director | 26,857 | 0 | 26,857 | 0.2% | 26 Feb, 2026 |
| 16 | Andrew G Hinson | Director | 17,675 | 0 | 17,675 | 0.1% | 18 Aug, 2021 |
| 17 | Catherine Coste | Director | 13,871 | 0 | 13,871 | 0.1% | 26 Feb, 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 |
|---|---|---|---|---|---|---|---|---|
| 17 Jul, 2026 | Sean Werner | Chief Technology Officer | Disposed F | 275 | $29.15 | $8.02K | 47,556 | Direct |
| 07 Jul, 2026 | Troy Wichterman | Chief Financial Officer | Disposed F | 844 | $27.79 | $23.45K | 213,249 | Direct |
| 07 Jul, 2026 | Aby J. Mathew | Evp Chief Scientific Officer | Disposed F | 516 | $27.79 | $14.34K | 388,460 | Direct |
| 07 Jul, 2026 | Todd Berard | Chief Marketing Officer | Disposed F | 293 | $27.79 | $8.14K | 162,649 | Direct |
| 18 Jun, 2026 | Troy Wichterman | Chief Financial Officer | Disposed F | 937 | $26.04 | $24.40K | 214,093 | Direct |
| 18 Jun, 2026 | Aby J. Mathew | Evp Chief Scientific Officer | Disposed F | 564 | $26.04 | $14.69K | 388,976 | Direct |
| 18 Jun, 2026 | Sean Werner | Chief Technology Officer | Disposed F | 420 | $26.04 | $10.94K | 47,831 | Direct |
| 18 Jun, 2026 | Greef Roderick De | President And Ceo | Disposed F | 2,775 | $26.04 | $72.26K | 730,971 | Direct |
| 18 Jun, 2026 | Todd Berard | Chief Marketing Officer | Disposed F | 470 | $26.04 | $12.24K | 162,942 | Direct |
| 08 Jun, 2026 | Todd Berard | Chief Marketing Officer | Disposed F | 356 | $26.10 | $9.29K | 163,412 | Direct |
| 08 Jun, 2026 | Troy Wichterman | Chief Financial Officer | Disposed F | 1,026 | $26.10 | $26.78K | 215,030 | Direct |
| 19 May, 2026 | Partners Master Fund, L.P. Casdin | TenPercentOwner | Disposed S | 300,000 | $22.65 | $6.80Mn | 5,657,165 | Indirect |
| 20 May, 2026 | Partners Master Fund, L.P. Casdin | TenPercentOwner | Disposed S | 250,000 | $23.70 | $5.93Mn | 5,407,165 | Indirect |
| 21 May, 2026 | Partners Master Fund, L.P. Casdin | TenPercentOwner | Disposed S | 650,000 | $23.70 | $15.41Mn | 4,757,165 | Indirect |
| 08 Apr, 2026 | Todd Berard | Chief Marketing Officer | Disposed F | 293 | $19.27 | $5.65K | 163,768 | Direct |
| 08 Apr, 2026 | Troy Wichterman | Chief Financial Officer | Disposed F | 844 | $19.27 | $16.26K | 216,056 | Direct |
| 23 Mar, 2026 | Karen A. Foster | Chief Quality And Operations | Disposed S | 2,577 | $19.17 | $49.40K | 108,758 | Direct |
| 23 Mar, 2026 | Karen A. Foster | Chief Quality And Operations | Disposed S | 2,577 | $19.17 | $49.40K | 108,758 | Direct |
| 23 Mar, 2026 | Karen A. Foster | Chief Quality And Operations | Disposed S | 2,577 | $19.17 | $49.40K | 108,758 | Direct |
| 23 Mar, 2026 | Karen A. Foster | Chief Quality And Operations | Disposed S | 2,577 | $19.17 | $49.40K | 108,758 | Direct |