Whale Analyzer
Top public holders · 13F and disclosure aggregation

Who owns TMO? 13F holders and whale ownership

TMO is tracked across public portfolios in Whale Analyzer. This page answers who owns TMO, which top funds are buying TMO, aggregate disclosed value, and recent position changes based on public data. Capital Group is the largest reported holder at $2.17B; the top five funds control 86.3% of reported ownership; institutions were net buying last quarter (5 increased, 3 reduced); the stock trades above the aggregate whale cost basis of $340.62. Top tracked holders include Capital Group, PRIMECAP Management, Andreas Halvorsen, and NPS Korea.

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NYQ · latest quote
$513.03
+$48.42 (+10.4%)
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9Tracked holders
$5.51BAggregate reported value
2026-05-21Page updated
4 increased, 3 reduced, 1 held, 1 newRecent changes

Top holders

InvestorReported valueSharesChange
Capital Group 13F portfolio
Capital Research Global Investors holdings
$2.17B4.4MIncreased
PRIMECAP Management 13F portfolio
PRIMECAP Management Company holdings
$974.5M2.0MReduced
Andreas Halvorsen 13F portfolio
Viking Global Investors holdings
$819.9M1.7MIncreased
NPS Korea 13F portfolio
National Pension Service holdings
$407.8M829.7KIncreased
Al Gore / David Blood 13F portfolio
Generation Investment Management holdings
$380.2M773.6KReduced
Dan Sundheim 13F portfolio
D1 Capital Partners holdings
$356.4M725.0KNew
Baillie Gifford 13F portfolio
Baillie Gifford & Co holdings
$343.3M698.4KReduced
Tom Gayner 13F portfolio
Markel Group holdings
$33.0M67.1KIncreased
Samuel Isaly 13F portfolio
OrbiMed Advisors holdings
$22.9M46.5KHeld

Ownership concentration

Reported ownership of TMO is highly concentrated across tracked institutions.

Whale activity this quarter

Across 9 tracked institutions, 5 increased, 3 reduced, 1 held. Net positioning is net buying.

Whale cost basis vs current price

The aggregate tracked cost basis is $340.62 versus a current price of $513.03, so TMO trades above its cost basis (+50.6%). Average unrealized P&L across tracked holders: 19%.

Sector positioning — Health Care

TMO 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 TMO 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.

Related stock holder pages

Learn more in Whale Analyzer Academy

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

Frequently asked questions

Who owns TMO stock?

Whale Analyzer tracks 9 public institutional holders of TMO with a combined reported value of $5.51B. See the holder table above for the largest tracked positions.

Which top funds are buying TMO?

Tracked institutions were net buying last quarter — 5 increased, 3 reduced, 1 held. Check the "Change" column: "New" = fresh position, "Increased" = added, "Reduced" = trimmed.

How concentrated is TMO ownership?

The top five tracked holders report 86.3% of aggregate ownership.

Is TMO above or below the whale cost basis?

The aggregate tracked cost basis is $340.62 versus a current price of $513.03 (+50.6%).

What does 13F ownership mean for TMO?

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