Korro Bio, Inc. (KRRO) Ownership
KRRO ownership summary
as of October 18, 2026- Institutions
- 105.2% of shares outstanding
- Insiders
- 0.89% of shares outstanding
- Shares outstanding
- 14.7M
- Float
- 10.6M shares available to trade
- Short interest
- 12.74% 1.7M shares short
- Days to cover
- 8.66 short interest up 7.9% vs prior month
- Institutions 105.22%
- Insiders 0.89%
KRRO top institutional holders
20 largest| # | Holder | % of shares | Shares | Value | Change | Reported |
|---|---|---|---|---|---|---|
| 1 | Lynx1 Capital Management, LP | 10.45% | 1.5M | $13.1M | — | June 30, 2026 |
| 2 | Nantahala Capital Management, LLC | 8.96% | 1.3M | $11.2M | +660,036 (+100.0%) | June 30, 2026 |
| 3 | NEA Management Company, LLC | 8.81% | 1.3M | $11.0M | — | June 30, 2026 |
| 4 | VR Adviser, LLC | 6.86% | 1.0M | $8.6M | — | June 30, 2026 |
| 5 | Atlas Venture Life Science Advisors, LLC | 6.54% | 963K | $8.2M | −174,265 (−15.3%) | June 30, 2026 |
| 6 | Balyasny Asset Management LLC | 6.46% | 952K | $8.1M | −88,271 (−8.5%) | June 30, 2026 |
| 7 | BlackRock Inc | 5.55% | 818K | $6.9M | +357,615 (+77.7%) | June 30, 2026 |
| 8 | Affinity Asset Advisors, LLC | 4.80% | 707K | $6.0M | — | June 30, 2026 |
| 9 | Adage Capital Partners Gp LLC | 3.67% | 541K | $4.6M | +312,568 (+136.9%) | June 30, 2026 |
| 10 | ADAR1 Capital Management LLC | 3.67% | 540K | $4.6M | — | June 30, 2026 |
| 11 | Vanguard Capital Management, LLC | 3.09% | 455K | $3.9M | +143,865 (+46.3%) | June 30, 2026 |
| 12 | Driehaus Capital Management LLC | 3.06% | 450K | $3.8M | — | June 30, 2026 |
| 13 | TCG Crossover Management, LLC | 2.83% | 416K | $3.5M | — | June 30, 2026 |
| 14 | Kalehua Capital Management LLC | 2.75% | 405K | $3.4M | +295,664 (+270.3%) | June 30, 2026 |
| 15 | Siren, L.L.C. | 2.36% | 348K | $3.0M | — | June 30, 2026 |
| 16 | AQR Capital Management LLC | 2.03% | 299K | $2.5M | +31,219 (+11.7%) | June 30, 2026 |
| 17 | Geode Capital Management, LLC | 2.02% | 297K | $2.5M | +123,227 (+71.0%) | June 30, 2026 |
| 18 | 72 Investment Holdings, LLC | 1.88% | 277K | $2.4M | — | June 30, 2026 |
| 19 | State Street Corp | 1.58% | 233K | $2.0M | +92,246 (+65.7%) | June 30, 2026 |
| 20 | Vanguard Portfolio Management, LLC | 1.52% | 224K | $1.9M | +74,992 (+50.5%) | June 30, 2026 |
Value at the latest close. Change = shares bought or sold in the latest quarterly filing (13F). In the top 20, 9 holders added 2.1M shares and 2 cut 263K.
KRRO top mutual fund and ETF holders
20 largest| # | Holder | % of shares | Shares | Value | Change | Reported |
|---|---|---|---|---|---|---|
| 1 | Vanguard MStar Total Stk Mkt Idx Invest | 2.11% | 311K | $2.6M | — | August 31, 2026 |
| 2 | iShares Russell 2000 ETF | 1.96% | 289K | $2.4M | −3,328 (−1.1%) | September 30, 2026 |
| 3 | Fidelity Small Cap Index | 0.83% | 122K | $1.0M | +708 (+0.6%) | July 31, 2026 |
| 4 | Vanguard Strategic Small-Cap Equity Inv | 0.72% | 106K | $903,294 | +18,055 (+20.4%) | June 30, 2026 |
| 5 | iShares Russell 2000 Value ETF | 0.56% | 83K | $704,551 | +126 (+0.2%) | September 30, 2026 |
| 6 | F/m Emerald Life Sciences Innovation ETF | 0.44% | 65K | $555,603 | — | September 30, 2026 |
| 7 | Vanguard Russell 2000 ETF | 0.43% | 64K | $543,717 | +1,320 (+2.1%) | August 31, 2026 |
| 8 | Fidelity Extended Market Index | 0.42% | 62K | $525,455 | +5,815 (+10.4%) | August 31, 2026 |
| 9 | iShares Micro-Cap ETF | 0.24% | 35K | $299,264 | −243 (−0.7%) | September 30, 2026 |
| 10 | Vanguard Health Care ETF | 0.19% | 29K | $242,822 | +120 (+0.4%) | August 31, 2026 |
| 11 | Schwab Small Cap Index | 0.18% | 27K | $228,126 | — | August 31, 2026 |
| 12 | Stt Strt SPDR® Russell2000 US SmCapETF | 0.16% | 24K | $203,268 | +1,152 (+5.1%) | August 31, 2026 |
| 13 | iShares Russell 2000 Small-Cap Idx Instl | 0.14% | 21K | $176,821 | — | August 31, 2026 |
| 14 | Fidelity Total Market Index | 0.14% | 20K | $170,895 | — | August 31, 2026 |
| 15 | Fidelity Series Total Market Index | 0.12% | 18K | $153,525 | +1,424 (+8.5%) | August 31, 2026 |
| 16 | Avantis US Small Cap Equity ETF | 0.11% | 16K | $134,057 | — | September 30, 2026 |
| 17 | Nuveen Small Cap Blend Idx R6 | 0.10% | 15K | $126,331 | — | August 31, 2026 |
| 18 | Vanguard VIF Small Co Gr | 0.10% | 15K | $124,124 | +14,620 (0.0%) | June 30, 2026 |
| 19 | Fidelity Small Cap Value Index | 0.09% | 13K | $108,791 | — | July 31, 2026 |
| 20 | EQ/2000 Managed Volatility IB | 0.08% | 12K | $104,087 | — | August 31, 2026 |
Funds report holdings monthly or quarterly; dates differ by fund.
KRRO insider transactions
latest 9| Date | Name | Transaction | Price | Shares | Value |
|---|---|---|---|---|---|
| 2026-03-31 | Lynx1 Capital Management Lp | Buy | $10.60 | 520 | $5,512 |
| 2026-03-10 | Anthony A Jr. Florence | Buy | $11.11 | 207,100 | $2.3M |
| 2026-03-10 | Edward T Mathers | Buy | $11.11 | 207,100 | $2.3M |
| 2026-03-10 | Enterprise Associates 17 New | Buy | $11.11 | 207,100 | $2.3M |
| 2026-03-10 | Forest Baskett | Buy | $11.11 | 207,100 | $2.3M |
| 2026-03-10 | Mohamad Makhzoumi | Buy | $11.11 | 207,100 | $2.3M |
| 2026-03-10 | Paul Edward Walker | Buy | $11.11 | 207,100 | $2.3M |
| 2026-03-10 | Rick Yang | Buy | $11.11 | 207,100 | $2.3M |
| 2026-03-10 | Scott D Sandell | Buy | $11.11 | 207,100 | $2.3M |
Reported trades by company officers, directors and other filers (including disclosures by members of Congress where EODHD lists them). "—" where the filing gives no share count.
KRRO shares outstanding
Year-end shares outstanding, adjusted for splits.
Who owns KRRO
Institutional investors own 105.2% of Korro Bio's shares and insiders 0.89%. The largest holder is Lynx1 Capital Management, LP with 10.45% of the shares (1.5M), as of June 30, 2026. Among the top 20 institutions, 9 added shares and 2 reduced their stake in the latest filings. Short interest is 12.74% of the float, or 8.66 days of average trading volume. The share count rose 1,423.0% since 2019.
Related: KRRO analyst forecast, KRRO key metrics. See the KRRO stock overview for the latest quote and news.
KRRO ownership FAQ
Who owns the most Korro Bio stock?
The largest shareholders of Korro Bio are Lynx1 Capital Management, LP (10.45%), Nantahala Capital Management, LLC (8.96%), NEA Management Company, LLC (8.81%), VR Adviser, LLC (6.86%), Atlas Venture Life Science Advisors, LLC (6.54%).
What percentage of Korro Bio is owned by institutions?
Institutions hold 105.2% of Korro Bio's shares outstanding; insiders hold 0.89%.
Which funds own Korro Bio?
The largest fund holders of Korro Bio are Vanguard MStar Total Stk Mkt Idx Invest (2.11%), iShares Russell 2000 ETF (1.96%), Fidelity Small Cap Index (0.83%), Vanguard Strategic Small-Cap Equity Inv (0.72%), iShares Russell 2000 Value ETF (0.56%).
What is Korro Bio's short interest?
1.7M shares of Korro Bio were sold short, 12.74% of the float; at the average daily volume it would take 8.66 days to cover.
Are insiders buying or selling Korro Bio?
Of the latest 9 reported insider transactions in Korro Bio (since March 10, 2026), 9 were purchases and 0 were sales.
How many shares of Korro Bio are outstanding?
Korro Bio has 14.7M shares outstanding, of which 10.6M are in the public float.