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MRK Institutional Ownership & 13F Holders | SmartMoneyDB

MRKMERCK & CO INC

COM · CUSIP 58933Y105

Smart Money Ownership

Of the 17 tracked institutions holding MRK, 11 have a 3-year clone track record — 9 of them beat the S&P. Average holder's clone alpha: +3.3pt. It's a gauge of who owns the name, not just how many.

Steve Cohen

$110.8M · 0.2% of book

+11.9pt

Ken Griffin

$459.7M · 0.3% of book

Capital Research Global Investors

$248.0M

MRK (MERCK & CO INC) Institutional Ownership Summary

Among the 17 tracked institutional investors we monitor, MRK (MERCK & CO INC) is held with a combined value of $94.88B across 819,686,058 shares. The largest holder is BlackRock, Inc. with a position worth $27.17B (0.48% of their portfolio). 8 funds increased their holdings. 9 funds reduced their position.

Total Institutional Value

$94.88B

Total Shares Held

819,686,058

Institutional Holders

% of Shares Outstanding

33.2%

of 2.47B shares · SEC 2026-04-30

Days to Cover

2.3+3.7%

31.38M shares short · FINRA 2026-06-30

Tracked 13F institutions hold 33.2% of MRK's shares outstanding. This is a floor: 13F filings arrive on a ~45-day lag and we track only a subset of institutional filers, so true institutional ownership is higher. Shares-outstanding is the latest SEC cover-page figure (as of 2026-04-30), not a live float.

This Quarter's Biggest Movers

Ranked by estimated dollars moved (share change × implied price). 13F data lags up to 45 days.

Biggest Buyers

BlackRock, Inc.+3% shares~$816.8M PRICE T ROWE ASSOCIATES INC /MD/+23% shares~$516.5M FMR LLC+9% shares~$442.1M VANGUARD GROUP INC+1% shares~$238.8M Fisher Asset Management, LLC+6% shares~$188.5M

13F Institutional Holders

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WELLINGTON MANAGEMENT GROUP LLP

Fisher Asset Management, LLC

1.08% of book+6.3%

$3.18B

PRICE T ROWE ASSOCIATES INC /MD/

0.32% of book+22.9%

$2.77B

HARRIS ASSOCIATES L P

1.99% of book-12.2%

$1.49B

AQR CAPITAL MANAGEMENT LLC

0.48% of book-23.3%

$1.04B

Grantham, Mayo, Van Otterloo & Co. LLC

2.16% of book+2.1%

$843.69M

#	Fund	Value↓	Shares	Portfolio %	Change
1	BlackRock, Inc.	$27.17B	225,830,330	0.48%	+3.1%
2	VANGUARD GROUP INC	$26.77B	254,322,763	0.39%	+0.9%
3	STATE STREET CORP	$14.45B	119,325,673	0.50%	-0.6%
4	WELLINGTON MANAGEMENT GROUP LLP	$10.14B	84,314,971	1.89%	-2.5%
5	FMR LLC	$5.35B	44,516,010	0.28%	+9.0%
6	Fisher Asset Management, LLC	$3.18B	26,436,284	1.08%	+6.3%
7	PRICE T ROWE ASSOCIATES INC /MD/	$2.77B	23,042,842	0.32%	+22.9%
8	HARRIS ASSOCIATES L P	$1.49B	12,366,933	1.99%	-12.2%
9	AQR CAPITAL MANAGEMENT LLC	$1.04B	8,628,486	0.48%	-23.3%
10	Grantham, Mayo, Van Otterloo & Co. LLC	$843.69M	7,013,777	2.16%	+2.1%

Congress Trading

29 members · 92 disclosed trades in MRK

Member	Type	Amount	Date
Alan Armstrong	Sell	$15,001 - $50,000	Mar 27, 2026
Josh Gottheimer	Buy	$1,001 - $15,000	Feb 4, 2026
Gilbert Cisneros	Buy	$1,001 - $15,000	Dec 19, 2025
Julie Johnson	Sell	$1,001 - $15,000

Frequently Asked Questions

Which institutional investors own the most MRK stock?

As of the latest SEC 13F filings, BlackRock, Inc. is the largest institutional holder of MRK with a position worth $27.17B, representing 0.48% of their portfolio. In total, 17 institutional investors hold MRK with a combined value of $94.88B.

What percentage of MRK is owned by institutional investors?

Institutional investors hold $94.88B worth of MRK stock across 17 positions. The largest institutional holder is BlackRock, Inc. with $27.17B in holdings.

What is a 13F filing and why does it matter for MRK?

A 13F filing is a quarterly report required by the SEC from institutional investment managers with over $100 million in assets. It discloses their holdings in U.S. equities. For MRK, these filings reveal which major funds are accumulating or reducing positions, providing insights into institutional sentiment.

Track MRK institutional moves

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