Tectonic Therapeutic, Inc.
Ownership
Ownership Structure
Who owns Tectonic Therapeutic, Inc. (TECX)? This page shows the largest institutions and funds, the ownership structure and the latest insider transactions. 60.9% of the shares are freely tradable; institutional investors hold 74.2%.
Largest Shareholders
Institutions
| Name | Stake (%) | Shares | Change (%) | Date |
|---|---|---|---|---|
| FMR Inc | 14.41 | 2,816,494 | +0.3 | 03/31/2026 |
| TCG Crossover Management, LLC | 6.16 | 1,204,891 | +0.0 | 06/30/2026 |
| Aberdeen Group PLC | 5.84 | 1,141,824 | +0.0 | 06/30/2026 |
| BlackRock Inc | 4.40 | 860,352 | +0.7 | 03/31/2026 |
| BRAIDWELL LP | 4.33 | 847,151 | -8.7 | 03/31/2026 |
| First Light Asset Management, LLC | 4.10 | 800,726 | +23.6 | 06/30/2026 |
| Baker Bros Advisors LP | 3.11 | 607,788 | -32.7 | 03/31/2026 |
| 5AM Venture Management, LLC | 3.10 | 606,660 | +0.0 | 06/30/2026 |
Funds
| Name | Stake (%) | Shares | Change (%) | Date |
|---|---|---|---|---|
| Fidelity Growth Compy Commingled Pl S | 5.82 | 1,138,399 | +0.0 | 07/31/2026 |
| Fidelity Growth Company Fund | 3.68 | 719,346 | +0.0 | 07/31/2026 |
Largest reported positions according to regulatory filings; stake as a percentage of shares outstanding, change versus the previous filing. Source: fundamentals data.
Insider holdings
| Person | Role | Shares | Value | As of | Type |
|---|---|---|---|---|---|
| McNamara Peter | Chief Scientific Officer | 55,285 | 1,492,695 $ | Aug 25, 2026 | direct |
Holdings as of each person's most recent SEC Form 4 filing — excluding options and RSUs, which are not shares yet. Holdings may have changed between two filings.
Insiders
Insider Transactions
| Date | Person | Role | Type | Shares | Price | Value |
|---|---|---|---|---|---|---|
| Aug 25, 2026 | McNamara Peter | Chief Scientific Officer | Sell | 43 | 36.52 | 1,570 |
| Aug 25, 2026 | McNamara Peter | Chief Scientific Officer | Other | 43 | 14.71 | 633 |
| Aug 12, 2026 | McNamara Peter | Chief Scientific Officer | Sell | 43 | 35.00 | 1,505 |
| Aug 12, 2026 | McNamara Peter | Chief Scientific Officer | Other | 43 | 14.71 | 633 |
Reportable transactions by officers and major shareholders from SEC Form 4 filings. "Other" includes things like stock grants and option exercises without a buy/sell character. View all insider transactions →
Data as of: September 18, 2026 · Source: fundamental data & SEC filings (annual and quarterly reports, 10-K/10-Q)
Note: pure fact-based analysis, not investment advice and not a solicitation to buy or sell. All figures without guarantee.