Company · Ownership research

Merck & Co., Inc. MRK

CIK 0000310158 · CUSIP 58933Y105

Insider trading Initial holdings Institutional holders

Quarter-end disclosures, not live holdings.

Several CUSIPs are reported for this company; this page shows CUSIP 58933Y105 (MRK), not CUSIP 58933Y905 (MRK), CUSIP 58933Y955 (MRK), CUSIP 589331107 (MRK), and does not merge CUSIPs.

This page lists the top 20 of 3,819 rows by value; the complete set is available through the API.

Some filings reported values in thousands; those figures were scaled ×1,000 to dollars.

Top 20 institutions

Weight means this stock's share of the manager's own portfolio.

By reported value

#	Manager	Value	Manager weight	Change vs prior	Source
01	BlackRock, Inc. CIK 2012383 · View history	$27.17B 225,830,330 shares	0.48%	+6.73M(+3.10%)Added	SEC filing ↗ May 13, 2026	▾
02	VANGUARD CAPITAL MANAGEMENT LLC CIK 2100119 · Amended · View history	$19.37B 160,987,624 shares	0.48%	—	SEC filing ↗ May 15, 2026	▾
03	STATE STREET CORP CIK 93751 · View history	$14.45B 119,325,673 shares	0.50%	-714.50K(-0.60%)Reduced	SEC filing ↗ May 15, 2026	▾
04	WELLINGTON MANAGEMENT GROUP LLP CIK 902219 · View history	$10.14B 84,314,971 shares	1.89%	-2.12M(-2.50%)Reduced	SEC filing ↗ May 15, 2026	▾
05	VANGUARD PORTFOLIO MANAGEMENT LLC CIK 2100121 · Amended · View history	$8.10B 67,304,305 shares	0.42%	—	SEC filing ↗ May 8, 2026	▾
06	GEODE CAPITAL MANAGEMENT, LLC CIK 1214717 · View history	$7.14B 59,558,154 shares	0.44%	-489.83K(-0.80%)Reduced	SEC filing ↗ May 15, 2026	▾
07	JPMORGAN CHASE & CO CIK 19617 · Amended · View history	$6.26B 52,972,983 shares	0.42%	+23.77M(+81.40%)Added	SEC filing ↗ May 13, 2026	▾
08	CHARLES SCHWAB INVESTMENT MANAGEMENT INC CIK 884546 · View history	$5.99B 49,765,225 shares	0.91%	+1.20M(+2.50%)Added	SEC filing ↗ May 15, 2026	▾
09	MORGAN STANLEY CIK 895421 · View history	$5.73B 47,632,487 shares	0.35%	+2.69M(+6.00%)Added	SEC filing ↗ May 15, 2026	▾
10	FMR LLC CIK 315066 · View history	$5.35B 44,516,010 shares	0.28%	+3.68M(+9.00%)Added	SEC filing ↗ May 15, 2026	▾
11	BANK OF AMERICA CORP /DE/ CIK 70858 · View history	$3.70B 30,774,221 shares	0.27%	+2.92M(+10.50%)Added	SEC filing ↗ May 18, 2026	▾
12	NORTHERN TRUST CORP CIK 73124 · View history	$3.26B 27,090,023 shares	0.43%	-144.62K(-0.50%)Reduced	SEC filing ↗ May 14, 2026	▾
13	Fisher Asset Management, LLC CIK 850529 · View history	$3.18B 26,436,284 shares	1.08%	+1.56M(+6.30%)Added	SEC filing ↗ May 5, 2026	▾
14	PRICE T ROWE ASSOCIATES INC /MD/ CIK 80255 · View history	$2.77B 23,042,842 shares	0.32%	+4.29M(+22.90%)Added	SEC filing ↗ May 15, 2026	▾
15	Invesco Ltd. CIK 914208 · Amended · View history	$2.63B 21,855,101 shares	0.26%	+1.31M(+6.40%)Added	SEC filing ↗ May 12, 2026	▾
16	UBS AM, a distinct business unit of UBS ASSET MANAGEMENT AMERICAS LLC CIK 861177 · View history	$2.46B 20,414,819 shares	0.51%	+981.42K(+5.10%)Added	SEC filing ↗ May 13, 2026	▾
17	GOLDMAN SACHS GROUP INC CIK 886982 · View history	$2.42B 20,133,379 shares	0.32%	+784.66K(+4.10%)Added	SEC filing ↗ May 15, 2026	▾
18	Legal & General Group Plc CIK 764068 · View history	$2.35B 19,538,545 shares	0.54%	-238.30K(-1.20%)Reduced	SEC filing ↗ May 8, 2026	▾
19	Bank of New York Mellon Corp CIK 1390777 · View history	$2.25B 18,713,363 shares	0.41%	-451.16K(-2.40%)Reduced	SEC filing ↗ May 5, 2026	▾
20	AMERIPRISE FINANCIAL INC CIK 820027 · Amended · View history	$1.96B 16,262,708 shares	0.45%	+288.30K(+1.80%)Added	SEC filing ↗ Jul 17, 2026	▾

Showing 20 / 3,819 institutions. The complete set is available through the API.

Coverage & totals by quarter

Reporting institutions

3,819

Cancelled or null records excluded

Disclosed shares

1,931,694,118

Not deduplicated across managers

Disclosed value

$231.84B

Not market cap or free float

Reporting institutions by quarter

Counts also change with data coverage and reporting entities; they do not measure net buying. Distinct managers with a live stock row in this CUSIP; totals may include overlapping filings and are not a share of the company.

Merck & Co., Inc. · Q1 2026

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{"action":"holders","cusip":"58933Y105","quarter":"2026Q1","type":"positions","page_size":100}

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Sources, coverage & how to read this data

Figures are as reported to the SEC and merged with later amendments where Akkru could match them. Preview limits apply to what is listed, not to the totals, which come from the complete reported data. Nothing is zero-filled: a missing quarter or month is shown as missing.