Security key
878972108
Tectonic Therapeutic, Inc. - Common Stock, $0.0001 par value per share (TECX)
CUSIP: 878972108
Q1 2026 13F Holders as of 31 Mar 2026
- Security type / class
- Equity / Common Stock, $0.0001 par value per share
- Total 13F shares
- 13,811,456
- Total 13F value
- $426,833,189
- Share change
- +78,131
- Put/Call ratio
- 5%
- SEC-reported price per share
- $30.91
- Number of holders
- 111
- Value change
- +$10,638,500
- Number of buys
- 58
- Number of sells
- 56
- Shares outstanding
- 18,867,097
Holder snapshot
7 signals
Open additional details 1 more signal available
Security identity
Names, identifiers, and filing context for this profile.
1 source field
Report period
Q1 2026
Institutions
111
Top holders
10
TECX full security history
Ownership snapshot
Full 13F holder table
Tectonic Therapeutic, Inc. SEC filings
Tectonic Therapeutic, Inc. company facts
Broader feeds
Ownership snapshot
Top reported holders of TECX - Tectonic Therapeutic, Inc. - Common Stock, $0.0001 par value per share (13F + 13D/G + 3/4/5)
Grouped by holder across the latest SEC ownership disclosures. Start with comparable ownership when available, then verify the linked 13F, 13D/G, or 3/4/5 evidence.
Comparable stake leader
Timothy A. Springer
Disclosed value leader
Timothy A. Springer
Comparable rows
15/15
Latest evidence
12 Feb 2026
13D/G
13F
3/4/5
Lead comparable stake: 32%
13D/G row: Timothy A. Springer
Showing 1-6 of 15 holder rows.
Quick read
Timothy A. Springer leads the comparable SEC ownership view at 32%.
15 of 15 rows have a safely comparable ownership percentage. Use this as a filing-backed starting point, then open the detailed table for source links, reporting role, position value, share count, and filing date.
Open SEC evidence
Opens Timothy A. Springer's linked filing trail.
Comparable ownership
Top 5
Timothy A. Springer
32%
FMR LLC
15%
Terrance McGuire
6.3%
TCG Crossover GP II, LLC
6.2%
Aberdeen Group plc
6.1%
Ownership % is shown only when SEC disclosures are safely comparable across share classes.
Detailed SEC evidence table Showing 1-6 of 15 holder rows
| Holder | Evidence | Ownership % | Position | 12M Net Δ | As of |
|---|---|---|---|---|---|
| Timothy A. Springer |
13D/G
|
32%
|
$96,537,428
4,313,558 shares
|
+$1,958,250 | 03 Apr 2025 |
| FMR LLC |
13D/G
13F
Company
|
15%
|
$62,650,568
2,799,400 shares
|
+$28,714,995 | 31 Mar 2025 |
| Terrance McGuire |
13D/G
3/4/5
Director
|
6.3%
|
$14,725,503
657,976 shares
|
-$11,190,022 | 03 Apr 2025 |
| TCG Crossover GP II, LLC |
13D/G
Chen Yu
|
6.2%
|
$24,202,334
1,169,760 shares
|
$0 | 12 Feb 2026 |
| Aberdeen Group plc |
13F
13D/G
Company
|
6.1%
from 13D/G
|
$23,818,449
1,141,824 shares
|
— | 31 Dec 2025 |
| BRAIDWELL LP |
13F
Company
|
4.9%
|
$19,348,151
927,524 shares
|
— | 31 Dec 2025 |
How to read this table
Rows are grouped by holder and ranked first by SEC-reported ownership % when it is safely comparable, then by disclosed holdings value. — indicates unavailable or non-comparable values; "mixed-class rows" means the latest filing spans non-comparable classes.
13F holder rows
Institutional holders as of Q1 2026
Investor-level positions for this CUSIP, loaded as an interactive table.
Institutions
111
Shares
13,811,456
Rows available
111
| Investor | Option | Weight % | Change % | SEC-reported value | * Price | Shares | Share Change | Activity | Report Period |
|---|
* SEC-reported price is the security price as of the portfolio date and can indicate the last known price at which the security was still held. The marker flags a reported price that did not pass the local price check.
Compare Q1 2026 vs Q1 2026 Across Filers
Q1 2026 holders
111
Q1 2026 holders
111
Holder diff
0
| Investor | Q1 2026 Shares | Q1 2026 Shares | Share Diff | Share Chg % | Q1 2026 value | Q1 2026 value | Value change | Value Chg % |
|---|