Rallybio
RLYB · NASDAQ
$16.38+$0.03 (+0.18%)TodayMarket closed ·
Prev close $16.35
Who owns RLYB
Largest institutional holders, from their latest 13F filings
The 10 largest institutions hold 84.8% of RLYB’s shares.
- Adar1 Capital Management LLC17.5%
- Fidelity Management & Research Company LLC15.0%
- Viking Global Investors LP9.9%
- Hunt (Ronald M)8.4%
- Next 6 largest institutions34.0%
- All other shareholders15.2%
| Holder | Shares | % of shares |
|---|---|---|
| Adar1 Capital Management LLC | 926.35K | 17.48% |
| Fidelity Management & Research Company LLC | 794.72K | 14.99% |
| Viking Global Investors LP | 524.35K | 9.89% |
| Hunt (Ronald M) | 446.42K | 8.42% |
| New Leaf Venture Partners LLC | 412.70K | 7.79% |
| TPG Capital, L.P. | 378.55K | 7.14% |
| Hopfner (Robert Lorne) | 321.48K | 6.07% |
| Pivotal Bioventure Partners Investment Advisor LLC | 300.58K | 5.67% |
| Renaissance Technologies LLC | 199.91K | 3.77% |
| Nantahala Capital Management, LLC | 188.42K | 3.56% |
Largest mutual fund holders
| Holder | Shares | % of shares |
|---|---|---|
| Fidelity Growth Company Fund | 207.41K | 3.91% |
| Vanguard Total Stock Market Index Fund | 134.62K | 2.54% |
| Fidelity Growth Company K6 Fund | 56.78K | 1.07% |
| Fidelity Series Growth Company Fund | 53.60K | 1.01% |
| Vanguard Extended Market Index Fund | 32.45K | 0.61% |
Insider trades
Form 4 filings by officers, directors and large holders
Over the last 6 months, insiders bought $4.23M (14 trades) of RLYB on the open market, with no sales.
| Insider | Type | Shares | Value |
|---|---|---|---|
| Hopfner Robert Lorne | Option exercise | 2.06K | — |
| Hopfner Robert Lorne | Option exercise | 3.56K | — |
| Hopfner Robert Lorne | Option exercise | 9.20K | $5.15K |
| Hopfner Robert Lorne | Option exercise | 2.06K | $31.51K |
| Hopfner Robert Lorne | Option exercise | 3.56K | $8.48K |
| Hopfner Robert Lorne | Option exercise | 9.20K | $69.89K |
| Lieber Jonathan I | Option exercise | 3.91K | — |
| Lieber Jonathan I | Option exercise | 3.91K | $23.77K |
| Uden Stephen | Option exercise | 22.46K | — |
| Uden Stephen | Option exercise | 22.46K | $136.53K |
Short interest
Settled Sep 30, 2026
- Shares short
- 49.24K
- Days to cover
- 4.88
- % of shares outstanding
- 0.93%
- Average daily volume
- 10.10K
- Change since last report
- −11.4%
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