RALLYBIO CORP (RLYB)
Institutional ownership reported to the SEC as of Q2 2026, across 20 quarters.
Institutions report 11,973,648 shares against 5,310,499 outstanding. Shares only - option lines are excluded, which is why this can be compared with the company at all. The count comes from the cover page of the company's own most recent report, so it is dated when that was filed rather than at quarter end. Over 100% because an adviser and a sub-adviser can both report the same shares, and both are counted.
Calls and puts are the parts of reported value carried in derivative lines rather than shares, and they point in opposite directions: a manager holding calls is positioned for the security, one holding puts against it - or hedging shares they already own, which is why index funds carry so many. Most sites add the two together and report one figure, which averages away the only interesting part.
Holders
| Filer | Value | Shares | Their book | Held | Change |
|---|---|---|---|---|---|
| ADAR1 Capital Management, LLC | $14.8M | 926,352 | 0.68% | 2q | +4411.1%+$14.5M |
| CITADEL ADVISORS LLC | $13.9M | 7,777,987? | 0.00% | 2q | |
| FMR LLC | $12.7M | 794,720 | 0.00% | 2q | HELD |
| VIKING GLOBAL INVESTORS LP | $8.4M | 524,347 | 0.02% | 2q | HELD |
| TPG GP A, LLC | $6.1M | 378,551 | 0.12% | 2q | HELD |
| Nantahala Capital Management, LLC | $6.0M | 376,844 | 0.10% | 2q | +25.3%+$1.2M |
| Pivotal bioVenture Partners Investment Advisor LLC | $4.8M | 300,579 | 1.56% | 2q | HELD |
| RENAISSANCE TECHNOLOGIES LLC | $3.2M | 199,907 | 0.00% | 2q | +27.7%+$694.1K |
| VANGUARD CAPITAL MANAGEMENT LLC | $2.8M | 172,497 | 0.00% | 2q | +54.0%+$967.3K |
| Almitas Capital LLC | $1.9M | 120,682 | 0.46% | 2q | -36.9%-$1.1M |
| Rangeley Capital, LLC | $1.7M | 104,850 | 1.53% | 2q | +248.0%+$1.2M |
| Mariner, LLC | $809.1K | 50,566 | 0.00% | 2q | HELD |
| JANE STREET GROUP, LLC | $758.8K | 47,423 | 0.00% | new | NEW |
| GEODE CAPITAL MANAGEMENT, LLC | $512.9K | 32,047 | 0.00% | 2q | -9.5%-$54.1K |
| BlackRock, Inc. | $485.3K | 30,332 | 0.00% | 2q | +73.5%+$205.5K |
| STATE STREET CORP | $415.9K | 25,992 | 0.00% | new | NEW |
| HRT FINANCIAL LP | $410.0K | 25,657 | 0.00% | new | NEW |
| XTX Topco Ltd | $344.0K | 21,497 | 0.00% | 2q | +91.5%+$164.3K |
| VANGUARD FIDUCIARY TRUST CO | $269.1K | 16,820 | 0.00% | 2q | +24.2%+$52.4K |
| TWO SIGMA INVESTMENTS, LP | $265.9K | 16,619 | 0.00% | new | NEW |
| Quadrature Capital Ltd | $207.9K | 12,995 | 0.00% | new | NEW |
| DIMENSIONAL FUND ADVISORS LP | $180.5K | 11,280 | 0.00% | 2q | HELD |
| Vanguard Global Advisers, LLC | $23.1K | 1,442 | 0.00% | 2q | HELD |
| MERCER GLOBAL ADVISORS INC /ADV | $20.0K | 1,250 | 0.00% | new | NEW |
| Hartford Financial Management Inc. | $13.0K | 812 | 0.00% | 2q | HELD |
| SBI Securities Co., Ltd. | $8.1K | 506 | 0.00% | 2q | -3.4% |
| Caitong International Asset Management Co., Ltd | $6.9K | 434 | 0.00% | new | NEW |
| UBS Group AG | $2.3K | 146 | 0.00% | 2q | -98.2%-$124.3K |
| Truvestments Capital LLC | $2.1K | 129 | 0.00% | new | NEW |
| MORGAN STANLEY | $2.0K | 125 | 0.00% | 2q | -0.8% |
| BNP PARIBAS FINANCIAL MARKETS | $1.9K | 120 | 0.00% | 2q | HELD |
| Fortitude Family Office, LLC | $848 | 53 | 0.00% | 2q | HELD |
| WELLS FARGO & COMPANY/MN | $592 | 37 | 0.00% | 2q | -50.0% |
| EverSource Wealth Advisors, LLC | $496 | 31 | 0.00% | new | NEW |
| JPMORGAN CHASE & CO | $145 | 9 | 0.00% | 2q | -99.6%-$40.1K |
| Allworth Financial LP | $96 | 6 | 0.00% | 2q | HELD |
| BARCLAYS PLC | $48 | 3 | 0.00% | new | NEW |
| DANSKE BANK A/S | $16 | 1 | 0.00% | 2q | HELD |
Five percent filings
Anyone crossing 5% of a company must say so within days - far sooner than the next quarterly holdings report. A 13D declares an intent to influence the company; a 13G is the passive version. See all activist filings →
| Filed | Form | Filer | % of class |
|---|---|---|---|
| 2026-08-14 | 13G/A | Nantahala Capital Management, LLCwith 2 co-filers | 3.6% |
| 2026-08-14 | 13G/A | BALYASNY ASSET MANAGEMENT L.P.with 4 co-filers | 0.0% |
| 2026-08-14 | 13G/A | Cormorant Asset Management, LPwith 1 co-filers | 0.0% |
| 2026-08-06 | 13G/A | FMR LLCwith 1 co-filers | 15.0% |
| 2026-08-04 | 13G/A | Laurion Capital Management LPwith 2 co-filers | 0.0% |
What the company announced
Form 8-K filings from the last 120 days, showing only the items worth a reader's attention. Earnings releases, exhibit attachments and general disclosures are filed constantly and are left out. Filed is when the SEC received it; event is the date the company says the thing happened.
| Filed | Event date | What | Source |
|---|---|---|---|
| 2026-09-09 | 2026-09-08 | Directors or officers departed or appointed | filing |
What the insiders did
Open market purchases and sales reported on Form 4 in the last 180 days. Grants, option exercises and shares surrendered to cover tax are left out: they are compensation rather than a decision to buy or sell. Where a broker filled one order in tranches the lines are summed, because it was one decision.
Ten percent owners and entities
Usually an institution that crossed a reporting threshold, or a company taking a strategic stake, rather than an individual with a view.
| Date | Insider | Role | Side | Shares | Value |
|---|---|---|---|---|---|
| 2026-05-04 | ADAR1 Capital Management, LLC | 10% owner | Bought | 120,804 | $1.7M ×2 |
| 2026-05-13 | ADAR1 Capital Management, LLC | 10% owner | Bought | 79,259 | $1.1M ×2 |
| 2026-05-11 | ADAR1 Capital Management, LLC | 10% owner | Bought | 50,000 | $700.0K ×3 |
| 2026-05-05 | ADAR1 Capital Management, LLC | 10% owner | Bought | 35,101 | $491.3K |
| 2026-05-19 | ADAR1 Capital Management, LLC | 10% owner | Bought | 10,200 | $142.6K ×2 |
Quarter by quarter
Coverage begins with the quarter ending 2018-12-31. Earlier filings exist only as occasional late amendments, too sparse to describe a market, so they are not shown.
| Quarter | Holders | Value | Shares | New | Added | Trimmed | Options |
|---|---|---|---|---|---|---|---|
| Q2 2026 | 38 | $81.0M | 11,973,648 | 10 | 9 | 7 | 0.0% |
| Q1 2026 | 38 | $41.9M | 4,666,444 | 35 | 0 | 0 | 0.0% |
| Q4 2025 | 46 | $20.7M | 24,931,168 | 5 | 7 | 11 | 0.0% |
| Q3 2025 | 45 | $14.9M | 29,833,371 | 6 | 9 | 11 | 0.0% |
| Q2 2025 | 48 | $10.5M | 31,192,738 | 7 | 7 | 12 | 0.0% |
| Q1 2025 | 47 | $20.9M | 32,001,262 | 2 | 7 | 12 | 0.0% |
| Q4 2024 | 49 | $31.1M | 32,428,353 | 4 | 11 | 9 | 0.0% |
| Q3 2024 | 49 | $36.5M | 31,213,634 | 1 | 11 | 21 | 0.0% |
| Q2 2024 | 63 | $39.6M | 29,573,919 | 19 | 12 | 16 | 0.0% |
| Q1 2024 | 60 | $56.2M | 30,367,338 | 12 | 14 | 16 | 0.0% |
| Q4 2023 | 53 | $71.2M | 29,810,745 | 9 | 20 | 7 | 0.0% |
| Q3 2023 | 58 | $105.2M | 31,203,726 | 4 | 12 | 13 | 0.0% |
| Q2 2023 | 59 | $188.3M | 33,261,435 | 11 | 22 | 12 | 0.0% |
| Q1 2023 | 51 | $201.9M | 35,359,014 | 3 | 18 | 12 | 0.0% |
| Q4 2022 | 57 | $212.3M | 32,313,982 | 9 | 26 | 11 | 0.0% |
| Q3 2022 | 52 | $402.1M | 27,791,403 | 10 | 12 | 15 | 0.0% |
| Q2 2022 | 45 | $208.8M | 27,659,986 | 4 | 14 | 16 | 0.0% |
| Q1 2022 | 47 | $193.9M | 27,776,263 | 10 | 15 | 8 | 0.0% |
| Q4 2021 | 38 | $260.1M | 27,428,818 | 4 | 15 | 4 | 0.0% |
| Q3 2021 | 34 | $419.9M | 24,054,395 | 34 | 0 | 0 | 0.0% |