Rallybio Corp
RLYB- Exchange
- Nasdaq
- Industry
- Pharmaceutical Preparations
- SEC CIK
- 0001739410
No open-market purchases or sales by Rallybio Corp insiders were filed in the last 90 days; 37 institutions reported holding it in 13F filings for Q2 2026, worth $65.0M in total; Viking Global Investors is the only superinvestor holding it.
13F holders, Q1 2026
Institutional positions in Rallybio Corp as of Mar 31, 2026. Investment managers with $100 million or more in US stocks report their long positions on Form 13F within 45 days after each quarter ends. How 13F works
- Institutional holders
- 38
- −7 vs. Q4 2025
- Shares held
- 4.67M
- +1.68M (+56.1%) vs. Q4 2025Converted for a 1-for-8 split
- Total value
- $41.9M
- +$26.0M (+163.2%) vs. Q4 2025
- New holders
- 13
- 7 more added
- Sold out
- 20
- 10 more reduced
1 institution that held it in Q4 2025 haven't filed for Q1 2026 yet. Not filing isn't selling, so they aren't counted as sold out or in the changes above.
Compare with Q4 2025: new holders, sold out and not filed yet
Holders and value by quarter
Institutions reporting RLYB on Form 13F each quarter since Q1 2021, and the total value they reported. Values are as of each quarter end, so they also move with the share price.
| Quarter | Holders | Value |
|---|---|---|
| Q2 2026 | 37 | $65.0M |
| Q1 2026 | 38 | $41.9M |
| Q4 2025 | 46 | $16.6M |
| Q3 2025 | 45 | $14.1M |
| Q2 2025 | 48 | $10.5M |
| Q1 2025 | 47 | $20.9M |
| Q4 2024 | 49 | $31.1M |
| Q3 2024 | 49 | $36.5M |
| Q2 2024 | 66 | $42.4M |
| Q1 2024 | 62 | $55.9M |
| Q4 2023 | 54 | $75.9M |
| Q3 2023 | 58 | $105.2M |
| Q2 2023 | 59 | $188.3M |
| Q1 2023 | 53 | $183.3M |
| Q4 2022 | 58 | $212.3M |
| Q3 2022 | 53 | $402.1M |
| Q2 2022 | 47 | $208.8M |
| Q1 2022 | 47 | $193.9M |
| Q4 2021 | 38 | $260.1M |
| Q3 2021 | 34 | $419.9M |
| Q2 2021 | 0 | $0 |
| Q1 2021 | 0 | $0 |
Institutions, Q1 2026
Shares, value and share of portfolio for each institution holding Rallybio Corp; share changes are against Q4 2025.
| Institution | Shares | Value | % of portfolio | Change in shares | Action |
|---|---|---|---|---|---|
| FMR LLC | 793,451 | $7.12M | 0.00% | +581,653+274.6% | AddedConverted for a 1-for-8 split |
| Viking Global Investors LPSuperinvestorViking Global Investors | 524,347 | $4.70M | 0.01% | 00.0% | UnchangedConverted for a 1-for-8 split |
| Cormorant Asset Management, LP | 400,000 | $3.59M | 0.18% | +400,000 | New |
| TPG GP A, LLC | 378,551 | $3.40M | 0.09% | 00.0% | UnchangedConverted for a 1-for-8 split |
| Balyasny Asset Management LLC | 376,573 | $3.38M | 0.01% | +376,573 | New |
| Laurion Capital Management LP | 302,756 | $2.72M | 0.25% | +302,756 | New |
| Nantahala Capital Management, LLC | 300,635 | $2.70M | 0.17% | +300,635 | New |
| Pivotal bioVenture Partners Investment Advisor LLC | 300,579 | $2.70M | 0.96% | 00.0% | UnchangedConverted for a 1-for-8 split |
| 5AM Venture Management, LLC | 291,788 | $2.62M | 0.73% | −162,053−35.7% | ReducedConverted for a 1-for-8 split |
| Almitas Capital LLC | 191,206 | $1.72M | 0.39% | 00.0% | UnchangedConverted for a 1-for-8 split |
| Renaissance Technologies LLC | 156,527 | $1.40M | 0.00% | +52,066+49.8% | AddedConverted for a 1-for-8 split |
| Johnson & Johnson | 152,901 | $1.37M | 0.21% | −301,644−66.4% | ReducedConverted for a 1-for-8 split |
| Vanguard Capital Management LLC | 112,040 | $1.00M | 0.00% | +112,040 | New |
| AJU IB Investment Co., Ltd. | 94,334 | $846.2K | 2.77% | 00.0% | UnchangedConverted for a 1-for-8 split |
| Mariner, LLC | 50,566 | $453.6K | 0.00% | 00.0% | UnchangedConverted for a 1-for-8 split |
| Geode Capital Management, LLC | 35,425 | $317.8K | 0.00% | +4,424+14.3% | AddedConverted for a 1-for-8 split |
| Deltec Asset Management LLC | 33,750 | $302.7K | 0.06% | +33,750 | New |
| Rangeley Capital, LLC | 30,130 | $270.3K | 0.29% | +25,130+502.6% | AddedConverted for a 1-for-8 split |
| GTS Securities LLC | 22,016 | $197.5K | 0.01% | +22,016 | New |
| ADAR1 Capital Management, LLC | 20,535 | $184.2K | 0.01% | +20,535 | New |
| Citadel Advisors LLC | 19,886 | $178.4K | 0.00% | −11,844−37.3% | ReducedConverted for a 1-for-8 split |
| BlackRock, Inc. | 17,486 | $156.8K | 0.00% | −222−1.3% | ReducedConverted for a 1-for-8 split |
| Vanguard Fiduciary Trust Co | 13,547 | $121.5K | 0.00% | +13,547 | New |
| Dimensional Fund Advisors LP | 11,280 | $101.2K | 0.00% | +11,280 | New |
| XTX Topco Ltd | 11,226 | $100.7K | 0.00% | −938−7.7% | ReducedConverted for a 1-for-8 split |
| Acadian Asset Management LLC | 10,433 | $92.0K | 0.00% | 00.0% | UnchangedConverted for a 1-for-8 split |
| UBS Group AG | 7,914 | $71.0K | 0.00% | +7,342+1,283.3% | AddedConverted for a 1-for-8 split |
| JPMorgan Chase & Co | 2,497 | $20.1K | 0.00% | +2,487+24,261.0% | AddedConverted for a 1-for-8 split |
| Vanguard Global Advisers, LLC | 1,442 | $12.9K | 0.00% | +1,442 | New |
| Tower Research Capital LLC (TRC) | 907 | $8.14K | 0.00% | +342+60.4% | AddedConverted for a 1-for-8 split |
| Hartford Financial Management Inc. | 812 | $7.28K | 0.00% | 00.0% | UnchangedConverted for a 1-for-8 split |
| SBI Securities Co., Ltd. | 524 | $4.70K | 0.00% | −7−1.3% | ReducedConverted for a 1-for-8 split |
| Morgan Stanley | 126 | $1.13K | 0.00% | −454−78.3% | ReducedConverted for a 1-for-8 split |
| BNP Paribas Arbitrage, SA | 120 | $1.08K | 0.00% | −3−2.0% | ReducedConverted for a 1-for-8 split |
| Fortitude Family Office, LLC | 53 | $475 | 0.00% | +53 | New |
| Wells Fargo & Company | 37 | $332 | 0.00% | −1−1.3% | ReducedConverted for a 1-for-8 split |
| Allworth Financial LP | 6 | $54 | 0.00% | −0−4.0% | ReducedConverted for a 1-for-8 split |
| Danske Bank A/S | 1 | $9 | 0.00% | +1 | New |
| Canaan Partners XI LLC | 0 | $0 | 0.00% | −56,250−100.0% | Sold outConverted for a 1-for-8 split |
| Susquehanna International Group, LLP | 0 | $0 | 0.00% | −12,591−100.0% | Sold outConverted for a 1-for-8 split |
| State Street Corp | 0 | $0 | 0.00% | −7,759−100.0% | Sold outConverted for a 1-for-8 split |
| Northern Trust Corp | 0 | $0 | 0.00% | −4,766−100.0% | Sold outConverted for a 1-for-8 split |
| Two Sigma Investments, LP | 0 | $0 | 0.00% | −4,625−100.0% | Sold outConverted for a 1-for-8 split |
| Prudential Financial Inc | 0 | $0 | 0.00% | −3,638−100.0% | Sold outConverted for a 1-for-8 split |
| Virtu Financial LLC | 0 | $0 | 0.00% | −3,392−100.0% | Sold outConverted for a 1-for-8 split |
| HRT Financial LP | 0 | $0 | 0.00% | −2,673−100.0% | Sold outConverted for a 1-for-8 split |
| Resources Investment Advisors, LLC. | 0 | $0 | 0.00% | −2,500−100.0% | Sold outConverted for a 1-for-8 split |
| Two Sigma Advisers, LP | 0 | $0 | 0.00% | −2,413−100.0% | Sold outConverted for a 1-for-8 split |
| Gsa Capital Partners LLP | 0 | $0 | 0.00% | −2,413−100.0% | Sold outConverted for a 1-for-8 split |
| Ground Swell Capital, LLC | 0 | $0 | 0.00% | −1,925−100.0% | Sold outConverted for a 1-for-8 split |
| Great Valley Advisor Group, Inc. | 0 | $0 | 0.00% | −1,875−100.0% | Sold outConverted for a 1-for-8 split |
| Utah Retirement Systems | 0 | $0 | 0.00% | −1,655−100.0% | Sold outConverted for a 1-for-8 split |
| ACT Advisors, LLC. | 0 | $0 | 0.00% | −1,644−100.0% | Sold outConverted for a 1-for-8 split |
| Mercer Global Advisors Inc | 0 | $0 | 0.00% | −1,250−100.0% | Sold outConverted for a 1-for-8 split |
| Captrust Financial Advisors | 0 | $0 | 0.00% | −1,250−100.0% | Sold outConverted for a 1-for-8 split |
| Barclays PLC | 0 | $0 | 0.00% | −715−100.0% | Sold outConverted for a 1-for-8 split |
| Citigroup Inc | 0 | $0 | 0.00% | −492−100.0% | Sold outConverted for a 1-for-8 split |
| Bank of America Corp | 0 | $0 | 0.00% | −31−100.0% | Sold outConverted for a 1-for-8 split |
| Vanguard Group Inc | – | – | – | – | Not filed |