Zymeworks's top three insider shareholders as of September 29, 2026 are Capital, Llc Ecor1 (Director, 22.97Mn shares), Capital, Llc Ecor1 (TenPercentOwner, 19.97Mn shares), Group, Llc Redmile (TenPercentOwner, 6.08Mn shares).
| # | Insider | Position | Direct | Indirect | Total | Share of Insiders | Last Filed |
|---|---|---|---|---|---|---|---|
| 1 | Capital, Llc Ecor1 | Director, TenPercentOwner | 0 | 22,970,388 | 22,970,388 | 76.5% | 27 Jun, 2025 |
| 2 | Group, Llc Redmile | TenPercentOwner | 0 | 6,075,918 | 6,075,918 | 20.2% | 18 Oct, 2022 |
| 3 | Gregory Austin Ciongoli | Director | 488,500 | 0 | 488,500 | 1.6% | 12 Aug, 2025 |
| 4 | Kenneth Galbraith | Chair Ceo | 226,842 | 0 | 226,842 | 0.8% | 12 Jan, 2026 |
| 5 | Mark Hollywood | Evp Chief Operating Officer | 133,852 | 0 | 133,852 | 0.4% | 06 Jul, 2026 |
| 6 | Paul Andrew Moore | Chief Scientific Officer | 48,497 | 0 | 48,497 | 0.2% | 12 Jan, 2026 |
| 7 | Jeffrey T L Smith | Evp Chief Medical Officer | 26,708 | 0 | 26,708 | 0.1% | 12 Jan, 2026 |
| 8 | Neil A Klompas | President Coo | 17,032 | 0 | 17,032 | 0.1% | 14 Mar, 2023 |
| 9 | Neil Josephson | Chief Medical Officer | 14,449 | 0 | 14,449 | 0.0% | 23 Dec, 2022 |
| 10 | Christopher Astle | Svp Chief Financial Officer | 6,503 | 0 | 6,503 | 0.0% | 08 Jan, 2024 |
| 11 | Leone D Patterson | Evp, Chief Bus Fin Officer | 459 | 0 | 459 | 0.0% | 07 Jan, 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 |
|---|---|---|---|---|---|---|---|---|
| 06 Jul, 2026 | Mark Hollywood | Evp Chief Operating Officer | Acquired A | 939 | $22.22 | $20.86K | 133,852 | Direct |
| 13 May, 2026 | Paul R Schneider | Evp, General Counsel | Acquired A | 178,000 | $0.00 | $0 | 178,000 | Direct |
| 13 May, 2026 | Paul R Schneider | Evp, General Counsel | Acquired A | 119,000 | $0.00 | $0 | 119,000 | Direct |
| 09 Apr, 2026 | Scott Platshon | Evp, Chief Business Officer | Acquired A | 70,000 | $0.00 | $0 | 70,000 | Direct |
| 09 Apr, 2026 | Adam Schayowitz | Officer | Acquired A | 70,000 | $0.00 | $0 | 70,000 | Direct |
| 09 Apr, 2026 | Adam Schayowitz | Officer | Acquired A | 47,000 | $0.00 | $0 | 47,000 | Direct |
| 09 Apr, 2026 | Scott Platshon | Evp, Chief Business Officer | Acquired A | 47,000 | $0.00 | $0 | 47,000 | Direct |
| 09 Apr, 2026 | Scott Platshon | Evp, Chief Business Officer | Acquired A | 76,000 | $0.00 | $0 | 76,000 | Direct |
| 09 Apr, 2026 | Adam Schayowitz | Officer | Acquired A | 76,000 | $0.00 | $0 | 76,000 | Direct |
| 06 Apr, 2026 | Kristin Stafford | Evp, Chief Financial Officer | Acquired A | 178,000 | $0.00 | $0 | 178,000 | Direct |
| 06 Apr, 2026 | Kristin Stafford | Evp, Chief Financial Officer | Acquired A | 119,000 | $0.00 | $0 | 119,000 | Direct |
| 06 Apr, 2026 | Kristin Stafford | Evp, Chief Financial Officer | Acquired A | 50,000 | $0.00 | $0 | 50,000 | Direct |
| 12 Jan, 2026 | Brian N Cherry | Director | Acquired A | 23,000 | $0.00 | $0 | 23,000 | Direct |
| 12 Jan, 2026 | Mark Hollywood | Evp Chief Operating Officer | Acquired M | 17,666 | $0.00 | $0 | 139,033 | Direct |
| 12 Jan, 2026 | Brian N Cherry | Director | Acquired A | 15,400 | $0.00 | $0 | 15,400 | Direct |
| 12 Jan, 2026 | Mark Hollywood | Evp Chief Operating Officer | Disposed S | 6,120 | $22.67 | $138.76K | 132,913 | Direct |
| 12 Jan, 2026 | Mark Hollywood | Evp Chief Operating Officer | Disposed M | 17,666 | $0.00 | $0 | 35,334 | Direct |
| 12 Jan, 2026 | Mark Hollywood | Evp Chief Operating Officer | Acquired A | 70,000 | $0.00 | $0 | 70,000 | Direct |
| 12 Jan, 2026 | Mark Hollywood | Evp Chief Operating Officer | Acquired A | 47,000 | $0.00 | $0 | 47,000 | Direct |
| 12 Jan, 2026 | Mark Hollywood | Evp Chief Operating Officer | Acquired A | 66,000 | $0.00 | $0 | 66,000 | Direct |