KRRO

Korro Bio Inc Cross-source read$13.81 5.74%
Health CareCUSIP 500946108· EOD Sep 11, 2026

Among active 13F managers last quarter, 11 opened and 19 added, while 10 reduced; the largest holder to move was Atlas Venture Life Science Advisors, LLC (−15%). Over the last 180 days, 6 insiders sold and 1 insider bought, a net -$4.9M in open-market trades.

Tracked 13F holders
91
34 in Q2 2026 filings
13F value (tracked)
$164.0M
Smart-money readMixed
Net sellingNet buying
Funds · active managers, latest 13F
30 adding · 10 trimming
Insiders · Form 4 open-market, 180d
1 buying · 6 selling · -$4.9M
US House · STOCK Act, 180d
0 buying · 0 selling

The legs disagree, or only one of them leans.

Price & smart-money activity

$13.81 5.74%5Y -96.1%
$5.24$104.93$204.62$304.31$404.00202120222023202420252026255861110721011111091219812161611281524281035132911112
Hover for who · click for detailEnd-of-day closing prices52w $5.28 – $51.36

Who owns KRRO?

91 tracked 13F filers · ranked by shares held

91 tracked 13F filers disclose a position in KRRO as of the latest SEC 13F filings, a combined $164.0M 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
1Lynx1 Capital Management LP1.5M
$20.3M
Held
Q2 2026
2NEA Management Company, LLC1.3M
$17.1M
Held
Q2 2026
3Balyasny Asset Management L.P.1.0M
$11.8M
New
+1.0M sh
Q1 2026
4Venrock Adviser, LLC1.0M
$13.3M
Held
Q2 2026
5Atlas Venture Life Science Advisors, LLC963K
$12.7M
−15%
Reduced · −174K sh
Q2 2026
6BlackRock, Inc.818K
$10.8M
+78%
Added · +358K sh
Q2 2026
7Affinity Asset Advisors, LLC707K
$8.0M
New
+707K sh
Q1 2026
8Nantahala Capital Management, LLC660K
$8.7M
Held
Q2 2026
9ADAR1 Capital Management, LLC540K
$6.1M
New
+540K sh
Q1 2026
10Vanguard Capital Management LLC455K
$6.0M
+46%
Added · +144K sh
Q2 2026
11TCG Crossover Management, LLC416K
$5.5M
Held
Q2 2026
12Kalehua Capital Management LLC405K
$5.3M
+270%
Added · +296K sh
Q2 2026
13Siren, L.L.C.348K
$4.6M
Held
Q2 2026
14Geode Capital Management, LLC297K
$3.9M
+71%
Added · +123K sh
Q2 2026
15AQR Capital Management LLC268K
$3.0M
+559%
Added · +227K sh
Q1 2026
16State Street Corp233K
$3.1M
+66%
Added · +92K sh
Q2 2026
17Adage Capital Partners GP, L.L.C.228K
$2.6M
New
+228K sh
Q1 2026
18Vanguard Portfolio Management LLC224K
$2.9M
+50%
Added · +75K sh
Q2 2026
19Two Sigma Investments, LP165K
$1.9M
+110%
Added · +86K sh
Q1 2026
20Renaissance Technologies LLC136K
$1.5M
+82%
Added · +61K sh
Q1 2026
21Jane Street Group, LLC116K
$1.3M
−60%
Reduced · −173K sh
Q1 2026
22Vanguard Fiduciary Trust Co75K
$987K
+80%
Added · +33K sh
Q2 2026
23JPMorgan Chase & Co69K
$704K
24×
Added · +66K sh
Q1 2026
24Millennium Management LLC64K
$720K
−61%
Reduced · −97K sh
Q1 2026
25Emerald Mutual Fund Advisers Trust64K
$838K
+1.1%
Added · +707 sh
Q2 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 KRRO being bought or sold by institutions?

Last quarter, 11 funds opened a new position in KRRO and 19 added to an existing one, while 10 reduced. Based on 13F filings from active, signal-eligible managers (passive index funds and other mechanical holders are excluded from this count).

Opened
11
funds took a first position
Added
19
added to an existing position
Reduced
10
reduced, still holding
Biggest moves · ranked by size of the change, positions above a floor

Funds that own KRRO also own

CompanyCo-held byTheir position there
Cogent Biosciences IncCOGT41 funds$862.8M
Alphabet Inc-CL AGOOGL40 funds$63.1B
Amazon.com IncAMZN40 funds$59.5B
Broadcom IncAVGO40 funds$54.7B
Eli Lilly & CoLLY40 funds$29.5B
Tesla IncTSLA40 funds$25.9B
Intuitive Surgical IncISRG40 funds$8.5B
Capital One Financial CorpCOF40 funds$5.1B
Nvidia CorpNVDA39 funds$143.2B
Apple IncAAPL39 funds$101.6B
Microsoft CorpMSFT39 funds$75.7B
Meta Platforms Inc-Class AMETA39 funds$34.6B

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

Insider activity (Form 4)

Full insider page →
Buys · 180d
$84K
1 insider
Sells · 180d
$5.0M
6 insiders
Net · 180d
-$4.9M
32 open-market transactions
DateInsiderRoleActionSharesValue
Sep 11, 2026Dolan OliverSenior Vice President, FinanceSell (S)5$69
Sep 9, 2026Dolan OliverSenior Vice President, FinanceSell (S)6$82
Sep 8, 2026Dolan OliverSenior Vice President, FinanceSell (S)7K$99K
Aug 26, 2026Formela Jean FrancoisDirectorSell (S)
2 lots, same day
300$4K
Aug 19, 2026Formela Jean FrancoisDirectorSell (S)
2 lots, same day
28K$399K
Aug 11, 2026Formela Jean FrancoisDirectorSell (S)
2 lots, same day
2K$30K
Aug 10, 2026Lynx1 Capital Management LP10% OwnerBuy (P)1K$19K
Aug 6, 2026Lynx1 Capital Management LP10% OwnerBuy (P)5K$60K
Aug 4, 2026Aiyar RamPresident and CEO, DirectorSell (S)6K$63K
Jul 6, 2026Formela Jean FrancoisDirectorSell (S)
2 lots, same day
9K$130K
Jul 2, 2026Formela Jean FrancoisDirectorSell (S)
2 lots, same day
101K$1.4M
Jun 24, 2026Formela Jean FrancoisDirectorSell (S)
4 lots, same day
48K$707K

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?

Mixed signals

Where institutional funds (13F), corporate insiders (Form 4) and US House members (STOCK Act) are buying or selling the same name in the same window. Green is buying, red is selling.

SEC EDGAR 13F + Form 4 + US House STOCK Act{ }get_ticker_confluence · API & MCP

Signals by source

Insiders and Congress: last 180 days. Funds: latest 13F, top 100 holders incl. passive

SourceBuyingSellingNet
13F funds
Top 100 holders by value, passive included; the hero counts active managers only
4021
Insiders
Form 4 open-market
16-$4.9M
US House
STOCK Act trades
00$0
Sector rotation
KRRO is in Health Care, which smart money is rotating OUT OF
$5.0B

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

34 tracked filers in Q2 2026 filingsstill filing
04590Q3 2024Q1 2025Q3 2025Q1 2026Q2 2026
tracked filers holding their reported valueQ2 2026 filings so far: $49.6M
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

15 most recent

Keep exploring

Connected entities for KRRO

Browse more

Build

Ask your agent what changed in KRRO

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/KRRO/capital-change-brief"
Ask your agent
Use Arkolith's capital_change_brief for KRRO.
Tell me what changed, whether insider activity
corroborates it, and cite the SEC evidence.

13F holdings + Form 4 insider transactions + end-of-day price history + the live filing stream, joined for KRRO. Filings are public domain, sourced to SEC EDGAR; price series derived from end-of-day closes.