Caribou Biosciences, Inc. (CRBU) Ownership
CRBU ownership summary
as of October 18, 2026- Institutions
- 45.1% of shares outstanding
- Insiders
- 8.13% of shares outstanding
- Shares outstanding
- 107.2M
- Float
- 102.9M shares available to trade
- Short interest
- 12.50% 12.9M shares short
- Days to cover
- 11.05 short interest down 0.5% vs prior month
- Institutions 45.15%
- Insiders 8.13%
- Other investors 46.72%
CRBU top institutional holders
20 largest| # | Holder | % of shares | Shares | Value | Change | Reported |
|---|---|---|---|---|---|---|
| 1 | BlackRock Inc | 7.29% | 7.8M | $3.7M | +5.7M (+264.7%) | June 30, 2026 |
| 2 | Pfizer Inc | 4.38% | 4.7M | $2.2M | — | June 30, 2026 |
| 3 | Vanguard Capital Management, LLC | 3.93% | 4.2M | $2.0M | +441,340 (+11.7%) | June 30, 2026 |
| 4 | Mackenzie Investments | 3.41% | 3.7M | $1.7M | +2.7M (+287.2%) | June 30, 2026 |
| 5 | Renaissance Technologies Corp | 2.59% | 2.8M | $1.3M | +183,048 (+7.1%) | June 30, 2026 |
| 6 | Kynam Capital Management, LP | 2.33% | 2.5M | $1.2M | — | June 30, 2026 |
| 7 | Geode Capital Management, LLC | 2.22% | 2.4M | $1.1M | +1.4M (+133.3%) | June 30, 2026 |
| 8 | Acadian Asset Management LLC | 1.66% | 1.8M | $833,825 | +849,435 (+91.8%) | June 30, 2026 |
| 9 | State Street Corp | 1.52% | 1.6M | $767,306 | +1.2M (+285.8%) | June 30, 2026 |
| 10 | Bank of America Corp | 1.32% | 1.4M | $663,009 | +113,791 (+8.8%) | June 30, 2026 |
| 11 | Two Sigma Investments LLC | 0.98% | 1.0M | $491,647 | −713,655 (−40.6%) | June 30, 2026 |
| 12 | Dimensional Fund Advisors, Inc. | 0.91% | 975K | $458,306 | +302,127 (+44.9%) | June 30, 2026 |
| 13 | Charles Schwab Investment Management Inc | 0.72% | 776K | $364,553 | +216,167 (+38.6%) | June 30, 2026 |
| 14 | CAMBRIDGE Invest RESEARCH ADVISORS, INC. | 0.71% | 765K | $359,389 | +217,806 (+39.8%) | June 30, 2026 |
| 15 | FMR Inc | 0.68% | 727K | $341,671 | +3,156 (+0.4%) | June 30, 2026 |
| 16 | Northern Trust Corp | 0.67% | 713K | $335,022 | +495,230 (+227.4%) | June 30, 2026 |
| 17 | Maverick Capital Ltd | 0.61% | 653K | $306,629 | — | June 30, 2026 |
| 18 | Vanguard Portfolio Management, LLC | 0.57% | 614K | $288,425 | +613,801 (0.0%) | June 30, 2026 |
| 19 | Vanguard Fiduciary Trust Co | 0.57% | 606K | $284,942 | +86,270 (+16.6%) | June 30, 2026 |
| 20 | Green Alpha Advisors, LLC | 0.51% | 551K | $259,124 | +187,121 (+51.4%) | September 30, 2026 |
Value at the latest close. Change = shares bought or sold in the latest quarterly filing (13F). In the top 20, 16 holders added 14.7M shares and 1 cut 714K.
CRBU top mutual fund and ETF holders
20 largest| # | Holder | % of shares | Shares | Value | Change | Reported |
|---|---|---|---|---|---|---|
| 1 | Vanguard MStar Total Stk Mkt Idx Invest | 2.81% | 3.0M | $1.4M | — | August 31, 2026 |
| 2 | iShares Russell 2000 ETF | 2.15% | 2.3M | $1.1M | −26,560 (−1.1%) | September 30, 2026 |
| 3 | ACATIS Datini Valueflex Fonds A | 1.87% | 2.0M | $939,800 | — | August 31, 2026 |
| 4 | Canada Life US Small-Mid Cap Growth F | 1.35% | 1.4M | $678,615 | — | July 31, 2026 |
| 5 | Selectra J. Lamarck Biotech A | 1.33% | 1.4M | $672,239 | — | September 30, 2026 |
| 6 | Fidelity Small Cap Index | 0.93% | 997K | $468,656 | −1,229 (−0.1%) | July 31, 2026 |
| 7 | iShares Russell 2000 Value ETF | 0.83% | 885K | $415,911 | +1,342 (+0.2%) | September 30, 2026 |
| 8 | iShares Biotechnology ETF | 0.65% | 694K | $326,298 | −5,264 (−0.8%) | September 30, 2026 |
| 9 | Schwab US Small-Cap ETF™ | 0.53% | 571K | $268,206 | +378 (+0.1%) | September 30, 2026 |
| 10 | Vanguard Russell 2000 ETF | 0.49% | 528K | $248,102 | +10,440 (+2.0%) | August 31, 2026 |
| 11 | Mackenzie GQE US Small Cap F8 | 0.44% | 467K | $219,635 | +30,465 (+7.0%) | July 31, 2026 |
| 12 | Fidelity Extended Market Index | 0.42% | 447K | $210,168 | −109,467 (−19.7%) | August 31, 2026 |
| 13 | Fidelity Enhanced Small Cap Core ETF | 0.31% | 335K | $157,366 | +702 (+0.2%) | September 30, 2026 |
| 14 | Galileo - Biotech Innovation Fund S USD | 0.28% | 300K | $140,970 | — | March 31, 2026 |
| 15 | IG Mackenzie GQE U.S. Sm Md Cap Eq C NL | 0.27% | 295K | $138,494 | — | July 31, 2026 |
| 16 | iShares Micro-Cap ETF | 0.27% | 290K | $136,225 | −1,999 (−0.7%) | September 30, 2026 |
| 17 | Dimensional US Small Cap ETF | 0.24% | 255K | $119,983 | — | September 30, 2026 |
| 18 | Bruce | 0.23% | 250K | $117,475 | — | June 30, 2026 |
| 19 | AXS Green Alpha ETF | 0.21% | 224K | $105,322 | — | September 30, 2026 |
| 20 | Schwab Small Cap Index | 0.21% | 224K | $105,076 | — | August 31, 2026 |
Funds report holdings monthly or quarterly; dates differ by fund.
CRBU insider transactions
latest 4| Date | Name | Transaction | Price | Shares | Value |
|---|---|---|---|---|---|
| 2026-02-24 | Barbara G Mcclung | Sell | $1.96 | 6,938 | $13,598 |
| 2026-02-24 | Ruhi Ahmad Khan | Sell | $1.96 | 6,938 | $13,598 |
| 2026-02-24 | Timothy P Kelly | Sell | $1.96 | 3,147 | $6,168 |
| 2026-02-24 | Tina M Albertson | Sell | $1.96 | 1,066 | $2,089 |
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.
CRBU shares outstanding
Year-end shares outstanding, adjusted for splits.
Who owns CRBU
Institutional investors own 45.1% of Caribou Biosciences's shares and insiders 8.13%. The largest holder is BlackRock Inc with 7.29% of the shares (7.8M), as of June 30, 2026. Among the top 20 institutions, 16 added shares and 1 reduced their stake in the latest filings. Short interest is 12.50% of the float, or 11.05 days of average trading volume. The share count rose 1,081.7% since 2019.
Related: CRBU analyst forecast, CRBU key metrics. See the CRBU stock overview for the latest quote and news.
CRBU ownership FAQ
Who owns the most Caribou Biosciences stock?
The largest shareholders of Caribou Biosciences are BlackRock Inc (7.29%), Pfizer Inc (4.38%), Vanguard Capital Management, LLC (3.93%), Mackenzie Investments (3.41%), Renaissance Technologies Corp (2.59%).
What percentage of Caribou Biosciences is owned by institutions?
Institutions hold 45.1% of Caribou Biosciences's shares outstanding; insiders hold 8.13%.
Which funds own Caribou Biosciences?
The largest fund holders of Caribou Biosciences are Vanguard MStar Total Stk Mkt Idx Invest (2.81%), iShares Russell 2000 ETF (2.15%), ACATIS Datini Valueflex Fonds A (1.87%), Canada Life US Small-Mid Cap Growth F (1.35%), Selectra J. Lamarck Biotech A (1.33%).
What is Caribou Biosciences's short interest?
12.9M shares of Caribou Biosciences were sold short, 12.50% of the float; at the average daily volume it would take 11.05 days to cover.
Are insiders buying or selling Caribou Biosciences?
Of the latest 4 reported insider transactions in Caribou Biosciences (since February 24, 2026), 0 were purchases and 4 were sales.
How many shares of Caribou Biosciences are outstanding?
Caribou Biosciences has 107.2M shares outstanding, of which 102.9M are in the public float.