How many institutional investors hold RLYB?

2 tracked institutional investors disclosed a position in RLYB (RALLYBIO CORP) in their most recent 13F filing.

Who is the largest institutional holder of RLYB?

Ken Griffin, Citadel Advisors, holds the largest disclosed position in RLYB, valued at $13M.

Where does this RLYB ownership data come from?

SEC Form 13F-HR filings, accessed via EDGAR. 13F filings are disclosed quarterly with a 45-day reporting delay and cover U.S.-listed long equity positions only. This is not investment advice.

RLYB — RALLYBIO CORP

Name: RALLYBIO CORP (RLYB) — Institutional Ownership
Creator: InvestorLens
License: https://www.sec.gov/about/website-policies

Public company

For educational research only.InvestorLens analyzes public regulatory filings (SEC EDGAR, STOCK Act PTRs) that may be delayed by 45 days or more. Information shown is historical and is not financial, legal, or tax advice, nor a recommendation or solicitation to buy or sell any security. Always do your own research.

InvestorLens aggregates public filing data to show which tracked investors reported holdings in this stock. Dollar values represent reported position values, not market capitalization, and may be delayed up to 45 days. Not a recommendation.

Sourced from SEC EDGAR public filings

Why are billionaires buying RLYB?

Built from public SEC filings and public economic data. Not a recommendation.

Confidence

Institutional Conviction

Net distribution · 0 buying vs 0 selling last quarter

Macro Tailwind

Macro conditions are mixed for this sector

Why? — Evidence & Confidence ▾

No tracked investor changed their RLYB position last quarter. Macro conditions are mixed for this sector (Macro Tailwind 57/100 in a Contraction regime).

Supporting evidence

+2 tracked investors reported holding RLYB at their latest filing
+Macro Health is 57/100 in a Contraction regime — historically acceptable for this sectorsource

Contradicting evidence — always shown

−13F data is disclosed up to 45 days after quarter end — positions may have changed since

Know the limits

· 13F disclosure lag (up to 45 days)
· Tracked investors are a sample, not the whole market
· Sector regime fit is a historical average, not a guarantee

Every InvestorLens score shows its evidence — including what argues against it. Model conviction-v1 · generated 9/6/2026.

About RALLYBIO CORP (RLYB)

RALLYBIO CORP (RLYB) appears in the most recent 13F filings of 2 tracked institutional investors. The largest disclosed position is held by Ken Griffin (Citadel Advisors), valued at $13M. Across recent filings, tracked investors recorded 1 new positions, 0 increased, 1 reduced, and 0 exited. All data sourced from SEC 13F filings.

Smart Money Consensus™

Based on recent institutional activity in RLYB

/100

Mixed Activity

Added / Increased1

Reduced1

Exited0

BearishBullish

Crowded Trade Score™

How many top investors track RLYB

/100

Undiscovered

2investors

Only 2 tracked investors report this position.

UndiscoveredCrowded

151015+

RLYB Ownership Composition

How RALLYBIO CORP is held across tracked investor types, based on reported 13F positions.

Dominant Type

Multi-Strategy / Quant

60% of tracked value

Institutions

tracked investors

Total Reported

$21.1M

combined 13F value

Multi-Strategy / Quant60.3%
Other39.7%

Multi-Strategy / Quant(1)

60.3%

Other(1)

39.7%

Tracked investors currently reporting RLYB

2 tracked investors have since exited this position — listed separately below.

Investor	Firm	Shares	Market value	% of portfolio	As of
Ken Griffin	Citadel Advisors	7.7M	$12.7M	0.00%	Jun 30, 2026
Andreas Halvorsen	Viking Global Investors	524.3K	$8.4M	0.02%	Jun 30, 2026

Ken GriffinJun 30, 2026
Citadel Advisors
Shares
7.7M
Value
$12.7M
% Portfolio
0.00%
Andreas HalvorsenJun 30, 2026
Viking Global Investors
Shares
524.3K
Value
$8.4M
% Portfolio
0.02%

Previously held RLYB

These investors reported RLYB in an earlier quarter but not in their most recent 13F. Figures below are their last reported position, not a current holding.

Investor	Firm	Last reported shares	Value then	Last held
Izzy Englander	Millennium Management	179.8K	$60.8K	Jun 30, 2025
Paul Tudor Jones	Tudor Investment Corp	10.4K	$13.9K	Jun 30, 2024

Recent activity

Investor	Action	Δ %	Current value	Filing date
Andreas Halvorsen	Unchanged	0.00%	$4M	Feb 14, 2025
Andreas Halvorsen	Unchanged	0.00%	$2.7M	May 15, 2025
Andreas Halvorsen	Unchanged	0.00%	$1.4M	Aug 14, 2025
Andreas Halvorsen	Unchanged	0.00%	$2.1M	Nov 14, 2025
Andreas Halvorsen	Unchanged	0.00%	$2.9M	Feb 17, 2026
Andreas Halvorsen	Reduced	-87.50%	$4.7M	May 15, 2026
Andreas Halvorsen	Unchanged	0.00%	$8.4M	Aug 14, 2026
Andreas Halvorsen	New	—	$4.9M	Nov 14, 2024

Andreas Halvorsen
Unchanged
$4M(0.00%)Feb 14, 2025
Andreas Halvorsen
Unchanged
$2.7M(0.00%)May 15, 2025
Andreas Halvorsen
Unchanged
$1.4M(0.00%)Aug 14, 2025
Andreas Halvorsen
Unchanged
$2.1M(0.00%)Nov 14, 2025
Andreas Halvorsen
Unchanged
$2.9M(0.00%)Feb 17, 2026
Andreas Halvorsen
Reduced
$4.7M(-87.50%)May 15, 2026
Andreas Halvorsen
Unchanged
$8.4M(0.00%)Aug 14, 2026
Andreas Halvorsen
New
$4.9MNov 14, 2024

Frequently asked questions

How many institutional investors hold RLYB?: 2 tracked institutional investors disclosed a position in RLYB (RALLYBIO CORP) in their most recent 13F filing.
Who is the largest institutional holder of RLYB?: Ken Griffin, Citadel Advisors, holds the largest disclosed position in RLYB, valued at $13M.
Did institutional ownership of RLYB increase or decrease?: Across recent 13F filings, tracked investors recorded 1 new positions, 0 increased, 1 reduced, and 0 fully exited RLYB.
Where does this RLYB ownership data come from?: SEC Form 13F-HR filings, accessed via EDGAR. 13F filings are disclosed quarterly with a 45-day reporting delay and cover U.S.-listed long equity positions only. This is not investment advice.