TECX

Tectonic Therapeutic Inc Cross-source read
Health CareCUSIP 878972108

Among active 13F managers last quarter, 12 opened and 18 added, while 21 reduced; the largest holder to move was First Light Asset Management, LLC (+24%). Over the last 180 days, 2 insiders sold and none bought, a net -$72K in open-market trades.

Tracked 13F holders
113
39 in Q2 2026 filings
13F value (tracked)
$450.2M
Smart-money readMixed
Net sellingNet buying
Funds · active managers, latest 13F
30 adding · 21 trimming
Insiders · Form 4 open-market, 180d
0 buying · 2 selling · -$72K

The legs disagree, or only one of them leans.

Who owns TECX?

113 tracked 13F filers · ranked by shares held

113 tracked 13F filers disclose a position in TECX as of the latest SEC 13F filings, a combined $450.2M in reported value. Holders and values reflect the 13F filers Arkolith currently tracks, not the entire institutional universe. Counts and totals are a floor, not the full institutional ownership.

#FundSharesPosition valueLast moveAs ofHistory
1FMR LLC2.8M
$97.3M
+0.5%
Added · +14K sh
Q2 2026
2TCG Crossover Management, LLC1.2M
$41.4M
Held
Q2 2026
3Aberdeen Group plc1.1M
$35.3M
Held
Q1 2026
4BlackRock, Inc.863K
$29.7M
+0.3%
Added · +2K sh
Q2 2026
5First Light Asset Management, LLC801K
$27.5M
+24%
Added · +153K sh
Q2 2026
6Baker Bros. Advisors LP608K
$20.9M
Held
Q2 2026
75AM Venture Management, LLC607K
$20.9M
Held
Q2 2026
8Braidwell LP597K
$20.5M
−30%
Reduced · −250K sh
Q2 2026
9Vanguard Capital Management LLC489K
$16.8M
+3.2%
Added · +15K sh
Q2 2026
10Vestal Point Capital, LP425K
$14.6M
+30%
Added · +97K sh
Q2 2026
11Kennedy Capital Management LLC287K
$8.9M
+37%
Added · +77K sh
Q1 2026
12Geode Capital Management, LLC270K
$9.3M
+0.8%
Added · +2K sh
Q2 2026
13Marshall Wace, LLP230K
$7.1M
+643%
Added · +199K sh
Q1 2026
14Orbimed Advisors LLC227K
$7.8M
Held
Q2 2026
15State Street Corp220K
$7.6M
+3.0%
Added · +6K sh
Q2 2026
16Ikarian Capital, LLC206K
$7.1M
+31%
Added · +48K sh
Q2 2026
17Squarepoint Ops LLC164K
$5.1M
−18%
Reduced · −35K sh
Q1 2026
18Ameriprise Financial Inc143K
$4.4M
New
+143K sh
Q1 2026
19D. E. Shaw & Co., Inc.116K
$3.6M
−3.4%
Reduced · −4K sh
Q1 2026
20Wells Fargo & Company113K
$3.5M
−6.4%
Reduced · −8K sh
Q1 2026
21Soleus Capital Management, L.P.102K
$3.5M
−16%
Reduced · −20K sh
Q2 2026
22Woodline Partners LP100K
$3.4M
Held
Q2 2026
23Vanguard Portfolio Management LLC94K
$3.2M
+48%
Added · +31K sh
Q2 2026
24Citadel Advisors LLC90K
$3.1M
Added
Added · +90K sh
Q2 2026
25Northern Trust Corp78K
$2.4M
+8.4%
Added · +6K sh
Q1 2026

Holders and values reflect the 13F filers Arkolith currently tracks, not the entire institutional universe. Counts and totals are a floor, not the full institutional ownership.

Is TECX being bought or sold by institutions?

Last quarter, 12 funds opened a new position in TECX and 18 added to an existing one, while 21 reduced. Based on 13F filings from active, signal-eligible managers (passive index funds and other mechanical holders are excluded from this count).

Opened
12
funds took a first position
Added
18
added to an existing position
Reduced
21
reduced, still holding
Biggest moves · ranked by size of the change, positions above a floor

Funds that own TECX also own

CompanyCo-held byTheir position there
Eli Lilly & CoLLY49 funds$38.6B
Boston Scientific CorpBSX46 funds$5.6B
Insmed IncINSM46 funds$3.8B
Revolution Medicines IncRVMD46 funds$3.8B
Unitedhealth Group IncUNH45 funds$16.6B
Intuitive Surgical IncISRG45 funds$10.9B
Abbott LaboratoriesABT44 funds$7.6B
Bristol-Myers Squibb CoBMY44 funds$7.3B
Alnylam Pharmaceuticals IncALNY44 funds$3.1B
Microsoft CorpMSFT43 funds$106.8B
Amazon.com IncAMZN43 funds$80.8B
Cisco Systems IncCSCO43 funds$13.7B

Ranked by how many of TECX's tracked holders also hold each name. The last column is those co-holders' combined reported position in that name, not in TECX.

Insider activity (Form 4)

Full insider page →
Sells · 180d
$72K
2 insiders
Net · 180d
-$72K
5 open-market transactions
DateInsiderRoleActionSharesValue
Aug 25, 2026McNamara PeterChief Scientific OfficerSell (S)43$2K
Aug 12, 2026McNamara PeterChief Scientific OfficerSell (S)43$2K
Jun 30, 2026McNamara PeterChief Scientific OfficerSell (S)172$6K
May 4, 2026Ruddy Marcella K.Chief Medical OfficerSell (S)1K$32K
Apr 1, 2026Ruddy Marcella K.Chief Medical OfficerSell (S)1K$31K
Mar 6, 2026McNamara PeterChief Scientific OfficerSell (S)
2 lots, same day
6K$189K
Mar 6, 2026Ruddy Marcella K.Chief Medical OfficerSell (S)10K$300K
Mar 4, 2026McNamara PeterChief Scientific OfficerSell (S)2K$41K
Mar 3, 2026McNamara PeterChief Scientific OfficerSell (S)2K$36K
Feb 11, 2026Reicin AliseChief Executive Officer, DirectorBuy (P)3K$53K
Feb 10, 2026Lochner DanielChief Financial OfficerBuy (P)6K$130K
Apr 11, 2025Springer Timothy ADirector, 10% OwnerBuy (P)
2 lots, same day
63K$1.0M

One row per insider, day and transaction code; shares and value are summed across the lots. Every lot is on the full insider page and in the filing.

Do institutions, insiders and Congress agree?

The cross-source read for TECX was unavailable for this render. The API and MCP tool answer it live.

Capital Rotation reports where institutional capital disclosed rotating, as of the latest public SEC 13F filings. It is data, not investment advice, a recommendation, or a prediction. Filings lag about 45 days and cover long US equity positions only. Past disclosed flows do not indicate future prices. Do your own research; consult a licensed advisor.

Institutional ownership over time

39 tracked filers in Q2 2026 filingsstill filing
053106Q3 2024Q1 2025Q3 2025Q1 2026Q2 2026
tracked filers holding their reported valueQ2 2026 filings so far: $74.2M
Each bar counts tracked filers with a position in that quarter's filings, so the newest bar excludes filers still on an earlier quarter. Arkolith's tracked universe has grown over this window; part of any long-run rise is coverage, not new buyers.

Recent filings

0 most recent

No filings captured for this ticker in the live stream yet.

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Connected entities for TECX

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Ask your agent what changed in TECX

This stock page is the public Follow view. For one current, evidence-backed answer, use capital_change_brief through REST or MCP. It compares tracked 13F changes with qualifying Form 4 activity and cites the SEC evidence.

Copy-paste
curl -H "Authorization: Bearer YOUR_API_KEY" \
  "https://arkolith.com/api/v1/stocks/TECX/capital-change-brief"
Ask your agent
Use Arkolith's capital_change_brief for TECX.
Tell me what changed, whether insider activity
corroborates it, and cite the SEC evidence.

13F holdings + Form 4 insider transactions + the live filing stream, joined for TECX. Filings are public domain, sourced to SEC EDGAR.