Whale Analyzer
Top public holders · 13F and disclosure aggregation

Who owns MRK? 13F holders and whale ownership

MRK is tracked across public portfolios in Whale Analyzer. This page answers who owns MRK, which top funds are buying MRK, aggregate disclosed value, and recent position changes based on public data. NPS Korea is the largest reported holder at $693M; the top five funds control 100.0% of reported ownership; institutions were net buying last quarter (3 increased, 1 reduced); the stock trades above the aggregate whale cost basis of $74.49. Top tracked holders include NPS Korea, Samuel Isaly, Chris Bloomstran, and Horizon Kinetics.

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NYQ · latest quote
$128.66
+$14.79 (+13.0%)
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5Tracked holders
$782.6MAggregate reported value
2026-05-21Page updated
2 increased, 1 held, 1 new, 1 reducedRecent changes

Top holders

InvestorReported valueSharesChange
NPS Korea 13F portfolio
National Pension Service holdings
$693.1M5.8MReduced
Samuel Isaly 13F portfolio
OrbiMed Advisors holdings
$79.8M663.4KNew
Chris Bloomstran 13F portfolio
Semper Augustus Investments holdings
$5.4M44.6KIncreased
Horizon Kinetics 13F portfolio
Horizon Kinetics Asset Management holdings
$3.4M28.4KIncreased
Edgewood Management 13F portfolio
Edgewood Management LLC holdings
$928.4K7.7KHeld

Ownership concentration

Reported ownership of MRK is highly concentrated across tracked institutions.

Whale activity this quarter

Across 5 tracked institutions, 3 increased, 1 reduced, 1 held. Net positioning is net buying.

Whale cost basis vs current price

The aggregate tracked cost basis is $74.49 versus a current price of $128.66, so MRK trades above its cost basis (+72.7%). Average unrealized P&L across tracked holders: 96%.

Sector positioning — Health Care

MRK 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 MRK 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 MRK with these Whale Analyzer Academy guides:

Frequently asked questions

Who owns MRK stock?

Whale Analyzer tracks 5 public institutional holders of MRK with a combined reported value of $782.6M. See the holder table above for the largest tracked positions.

Which top funds are buying MRK?

Tracked institutions were net buying last quarter — 3 increased, 1 reduced, 1 held. Check the "Change" column: "New" = fresh position, "Increased" = added, "Reduced" = trimmed.

How concentrated is MRK ownership?

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

Is MRK above or below the whale cost basis?

The aggregate tracked cost basis is $74.49 versus a current price of $128.66 (+72.7%).

What does 13F ownership mean for MRK?

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