Who owns Rallybio Corp?
Prices and market caps: Cboe delayed data, at least 15 minutes delayed. Not real-time. Fundamentals from company filings.
Institutional ownership of RLYB from SEC Form 13F filings across 38 reporting managers. All positions are from one synchronized reporting period — 2026-06-30 books, filed up to 45 days after quarter end — so every row is comparable.
As of the 2026-06-30 reporting period, 38 institutions disclosed 11.7M shares of Rallybio Corp worth $76.2M — about 205.3% of shares outstanding; the largest disclosed holder is CITADEL ADVISORS LLC. Source: SEC Form 13F filings, parsed by EvidInvest.
38
13F holders
$76.2M
value, 2026 filers
205.3%
of shares outstanding (11.7M sh)
11
new positions (2026 filers)
Top institutional holders
ordered by shares owned · positions as of 2026-06-30 · % of fund = share of the manager's own book · % of co. = share of RLYB's shares outstanding
| # | Manager | Shares | Value | % of fund | % of co. | Δ shares QoQ |
|---|---|---|---|---|---|---|
| 1 | CITADEL ADVISORS LLC | 7.7M | $12.7M | 0.0% | 135.2% | +38649.8% |
| 2 | ADAR1 Capital Management, LLC | 926,352 | $14.8M | 0.7% | 16.3% | +4411.1% |
| 3 | FMR LLC | 794,720 | $12.7M | 0.0% | 13.9% | +0.2% |
| 4 | VIKING GLOBAL INVESTORS LP | 524,347 | $8.4M | 0.0% | 9.2% | 0.0% |
| 5 | TPG GP A, LLC | 378,551 | $6.1M | 0.1% | 6.6% | 0.0% |
| 6 | Pivotal bioVenture Partners Investment Advisor LLC | 300,579 | $4.8M | 1.6% | 5.3% | 0.0% |
| 7 | RENAISSANCE TECHNOLOGIES LLC | 199,907 | $3.2M | 0.0% | 3.5% | +27.7% |
| 8 | Nantahala Capital Management, LLC | 188,422 | $3.0M | 0.1% | 3.3% | -37.3% |
| 9 | VANGUARD CAPITAL MANAGEMENT LLC | 172,497 | $2.8M | 0.0% | 3% | +54.0% |
| 10 | Almitas Capital LLC | 120,682 | $1.9M | 0.5% | 2.1% | -36.9% |
| 11 | Rangeley Capital, LLC | 104,850 | $1.7M | 1.5% | 1.8% | +248.0% |
| 12 | Mariner, LLC | 50,566 | $809,056 | 0.0% | 0.9% | 0.0% |
| 13 | JANE STREET GROUP, LLCNEW | 47,423 | $758,768 | 0.0% | 0.8% | new |
| 14 | GEODE CAPITAL MANAGEMENT, LLC | 32,047 | $512,865 | 0.0% | 0.6% | -9.5% |
| 15 | BlackRock, Inc. | 30,332 | $485,312 | 0.0% | 0.5% | +73.5% |
| 16 | HRT FINANCIAL LPNEW | 25,657 | $410 | 0.0% | 0.5% | new |
| 17 | XTX Topco Ltd | 21,497 | $343,952 | 0.0% | 0.4% | +91.5% |
| 18 | VANGUARD FIDUCIARY TRUST CO | 16,820 | $269,120 | 0.0% | 0.3% | +24.2% |
| 19 | TWO SIGMA INVESTMENTS, LPNEW | 16,619 | $265,904 | 0.0% | 0.3% | new |
| 20 | STATE STREET CORPNEW | 12,996 | $207,936 | 0.0% | 0.2% | new |
| 21 | Quadrature Capital LtdNEW | 12,995 | $207,920 | 0.0% | 0.2% | new |
| 22 | DIMENSIONAL FUND ADVISORS LP | 11,280 | $180,480 | 0.0% | 0.2% | 0.0% |
| 23 | Vanguard Global Advisers, LLC | 1,442 | $23,072 | 0.0% | 0% | 0.0% |
| 24 | MERCER GLOBAL ADVISORS INC /ADVNEW | 1,250 | $20,000 | 0.0% | 0% | new |
| 25 | Hartford Financial Management Inc. | 812 | $12,992 | 0.0% | 0% | 0.0% |
Source: SEC Form 13F-HR filings (institutional managers over $100M in US-listed positions). 13Fs disclose long positions only, up to 45 days after quarter end; each manager's latest filed quarter is shown per row and dollar values are the manager's filed marks. Aggregates labeled "2026 filers" count only managers whose latest book is a 2026 quarter. Related: valuation · options positioning · supply chain. Research, not investment advice.