Zymeworks Inc.
Zymeworks Inc. (ZYME) Stock Ownership
Institutional vs insider vs public ownership from 13F and float data — top holders, activity, and insider trades below.
SEC 13F · FMP · ZYME · as of Sep 30, 2025
Ownership Breakdown
191
Institutional Holders
▲ 6 vs Q2
$1.26B
Total Inst. Value
▲ $310.24M vs Q2
73.57M
Shares Outstanding
freeFloat 92.55%
73.71M
13F Shares Held
▼ 1.90M vs Q2
Institutional ownership = 13F shares ÷ total outstanding. Insider % = 100 − free float. Public % = free float − institution %. Data: FMP /symbol-positions-summary + /shares-float + SEC EDGAR.
Top Institutional Holders
ZYME largest shareholders · institutional ownership
Q3 2025 · SEC 13F
Showing top 10 holders
| Holder | Shares | % Owned | Weight | Value | Reported | Change |
|---|---|---|---|---|---|---|
ECOR1 CAPITAL, LLC pharmaceutical preparations | 22.97M | 30.49% | 30.49% | $392.33B | Nov 14, 2025 | — held |
RUBRIC CAPITAL MANAGEMENT LP pharmaceutical preparations | 4.71M | 6.25% | 6.25% | $80.46B | Nov 14, 2025 | — held |
BLACKROCK, INC. pharmaceutical preparations | 3.99M | 5.30% | 5.30% | $68.14B | Nov 12, 2025 | ▲ 195.3K |
MORGAN STANLEY pharmaceutical preparations | 3.98M | 5.29% | 5.29% | $68.06B | May 27, 2026 | ▼ 193.0K |
BVF INC/IL pharmaceutical preparations | 3.94M | 5.23% | 5.23% | $67.27B | Nov 14, 2025 | ▼ 370.3K |
REDMILE GROUP, LLC pharmaceutical preparations | 3.71M | 4.92% | 4.92% | $63.29B | Nov 14, 2025 | ▼ 444.9K |
VANGUARD GROUP INC pharmaceutical preparations | 2.15M | 2.86% | 2.86% | $36.80B | Nov 7, 2025 | ▼ 310.3K |
PERCEPTIVE ADVISORS LLC pharmaceutical preparations | 2.09M | 2.78% | 2.78% | $35.71B | Nov 14, 2025 | ▲ 815.4K |
VESTAL POINT CAPITAL, LP pharmaceutical preparations | 1.76M | 2.34% | 2.34% | $30.15B | Nov 14, 2025 | ▲ 615.0K |
UBS ASSET MANAGEMENT AMERICAS INC pharmaceutical preparations | 1.71M | 2.27% | 2.27% | $29.21B | Nov 14, 2025 | ▼ 749.0K |
Data from SEC Form 13F filings. Ownership bar normalised to largest holder. Change flags: isNew / isSoldOut / changeInSharesNumber (FMP extract-analytics/holder).
Institutional Activity
Q3 2025 vs prior quarter
Q3 2025
20
Increased
+4.42M shares3
New Positions
first time holders23
Decreased
−3.27M shares0
Sold Out
fully exitedNet shares change (top 50)
+1.15M
+4.42M / −3.27M
Net new holders
+0
3 new / 0 exited
Based on top 50 institutional holders by position size. Fields: isNew, isSoldOut, changeInSharesNumber (FMP extract-analytics/holder, limit=50).
Insider Buying vs Selling
ZYME insider trading · insider activity
Source: SEC Form 4
11
Buy transactions
0
Sell transactions
0.00
Buy/Sell ratio
$0M
Total disposed
Recent Insider Transactions
Showing 10 most recent · Common Stock only
| Name · Role | Date | Type | Shares | Price | Value | After Trans. | Filing |
|---|---|---|---|---|---|---|---|
Schneider Paul R EVP, General Counsel | May 13, 2026 | Award | 178,000 | $24.57 | $4.37M | 178.0K | Form 4 ↗ |
Schayowitz Adam See Remarks | Apr 9, 2026 | Award | 76,000 | — | — | 76.0K | Form 4 ↗ |
Schayowitz Adam See Remarks | Apr 9, 2026 | Award | 70,000 | $27.35 | $1.91M | 70.0K | Form 4 ↗ |
Platshon Scott EVP, Chief Business Officer | Apr 9, 2026 | Award | 76,000 | — | — | 76.0K | Form 4 ↗ |
Platshon Scott EVP, Chief Business Officer | Apr 9, 2026 | Award | 70,000 | $27.35 | $1.91M | 70.0K | Form 4 ↗ |
Stafford Kristin EVP, Chief Financial Officer | Apr 6, 2026 | Award | 178,000 | $25.84 | $4.60M | 178.0K | Form 4 ↗ |
Source: /insider-trading/search (FMP stable). Buy/Sell direction: acquisitionOrDisposition A=Buy, D=Sell. RSU vesting (M-Exempt) excluded from sentiment bar. All data from SEC EDGAR public filings.
About institutional & insider ownership
Zymeworks Inc. (ZYME) is primarily owned by institutional investors, who hold approximately 100.0% of total shares outstanding. Company insiders own approximately 7.45%, while retail and public investors account for the remaining 0.00%.
The largest institutional shareholder of Zymeworks Inc. is ECOR1 CAPITAL, LLC, holding approximately 22.97 million shares — equal to 30.49% of outstanding shares — as of September 30, 2025.
A total of 191 institutional investors currently hold ZYME stock, with a combined institutional value of approximately $1.26 billion as of the most recent 13F filing period.
Frequently asked questions
ZYME ownershipZymeworks Inc. (ZYME) is primarily owned by institutional investors, who hold approximately 100.0% of shares. The largest shareholder is ECOR1 CAPITAL, LLC with a 30.49% stake. Company insiders hold 7.45%. Data sourced from SEC Form 13F as of September 30, 2025.