Whale Analyzer
Top public holders · 13F and disclosure aggregation

Who owns IONS? 13F holders and whale ownership

IONS is tracked across public portfolios in Whale Analyzer. This page answers who owns IONS, which top funds are buying IONS, aggregate disclosed value, and recent position changes based on public data. Baker Bros. Advisors is the largest reported holder at $154M; the top five funds control 100.0% of reported ownership; institutions were net buying last quarter (2 increased, 1 reduced); the stock trades below the aggregate whale cost basis of $81.4. Top tracked holders include Baker Bros. Advisors, Joseph Edelman, and Cathie Wood.

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NMS · latest quote
$81.18
+$7.06 (+9.5%)
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3Tracked holders
$213.3MAggregate reported value
2026-05-21Page updated
1 increased, 1 new, 1 reducedRecent changes

Top holders

InvestorReported valueSharesChange
Baker Bros. Advisors 13F portfolio
Baker Bros. Advisors holdings
$153.8M2.0MIncreased
Joseph Edelman 13F portfolio
Perceptive Advisors holdings
$37.8M504.0KNew
Cathie Wood 13F portfolio
ARK Investment Management holdings
$21.7M288.7KReduced

Ownership concentration

Reported ownership of IONS is highly concentrated across tracked institutions.

Whale activity this quarter

Across 3 tracked institutions, 2 increased, 1 reduced. Net positioning is net buying.

Whale cost basis vs current price

The aggregate tracked cost basis is $81.40 versus a current price of $81.18, so IONS trades below its cost basis (-0.3%). Average unrealized P&L across tracked holders: 52%.

Sector positioning — Health Care

IONS sits within the Health Care sector alongside 221 other tracked names. Compare whale ownership across peers:

How to use this page

Values are reported public positions from tracked 13F filers and disclosures — not real-time ownership totals. Open the live IONS dashboard for price charts and cross-investor scans, or read the SEC 13F guide.

This page is generated from public filings and public disclosures. It is for research and education only and is not investment advice.

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Learn more in Whale Analyzer Academy

Deepen your read on IONS with these Whale Analyzer Academy guides:

Frequently asked questions

Who owns IONS stock?

Whale Analyzer tracks 3 public institutional holders of IONS with a combined reported value of $213.3M. See the holder table above for the largest tracked positions.

Which top funds are buying IONS?

Tracked institutions were net buying last quarter — 2 increased, 1 reduced. Check the "Change" column: "New" = fresh position, "Increased" = added, "Reduced" = trimmed.

How concentrated is IONS ownership?

The top five tracked holders report 100.0% of aggregate ownership.

Is IONS above or below the whale cost basis?

The aggregate tracked cost basis is $81.40 versus a current price of $81.18 (-0.3%).

What does 13F ownership mean for IONS?

Use the interactive IONS dashboard on Whale Analyzer for real-time holder analysis, or read our 13F Alpha Signals Guide.