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Harris (Oakmark) increased MRK position by 4,248,797 shares

Mar 28, 2026Last updated Apr 16, 2026

This StonkWhisper whale intelligence report documents significant institutional position changes in $MRK based on SEC 13F filings and block-level trading data. Quarterly 13F disclosures are required for institutional investment managers with at least $100 million in qualifying assets under management. These filings reveal long positions in U.S. equities held as of quarter end. Material changes in institutional positioning — particularly from concentrated funds with a history of high-conviction bets — are tracked by StonkWhisper as leading indicators of institutional thesis formation or exit.

HARRIS ASSOCIATES L P AUM: $79.1B INCREASED

AUM: $79.1B · 228 holdings · Period: 2025-12-31

+4,248,797 Share Change

13,608,288 Current Shares

$1432.4B Current Value

1.81% Portfolio %

+45.4% Change %

Position Change Detail

Issuer MERCK & CO INC

Ticker MRK

Shares 9,359,491 → 13,608,288 +4,248,797

Value $785.5B → $1432.4B

Portfolio Weight 1.81%

Change Type Increased

Period of Report 2025-12-31

Other Harris (Oakmark) Positions This Period

Ticker	Issuer	Change Type	Share Change	Value
KDP	KEURIG DR PEPPER INC	Increased	+23,133,072	$2363.3B
WBD	WARNER BROS DISCOVERY INC	Decreased	15,863,984	$2224.2B
APA	APA CORPORATION	Decreased	12,920,320	$278.1B
CTVA	CORTEVA INC	Increased	+10,484,052	$1099.4B
ZBH	ZIMMER BIOMET HOLDINGS INC	Increased	+7,300,436	$1064.2B
BAC	BANK AMERICA CORP	Decreased	7,091,720	$1050.9B
NKE	NIKE INC	Increased	+6,177,991	$918.9B
DAL	DELTA AIR LINES INC DEL	Increased	+6,162,045	$1312.7B
TRGP	TARGA RES CORP	Increased	+5,420,811	$1745.1B
CMCSA	COMCAST CORP NEW	Increased	+5,400,310	$803.4B

Other Whales Moving MRK This Period

Manager	Change Type	Share Change
Arrowstreet	Decreased	8,764,580
Millennium	Increased	+5,996,251
Two Sigma	Decreased	1,955,401
State Street	Increased	+1,859,990
Adage Capital	Increased	+1,634,216
Balyasny	Increased	+1,502,303
ExodusPoint	Decreased	838,093
American Century	Increased	+808,970
Fisher Investments	Increased	+805,201
Acadian	Decreased	608,296

View all sentiment, news, and whale activity for MRK (MERCK & CO INC).

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Data sourced from SEC 13F institutional holdings filings. This page does not constitute financial advice. StonkWhisper presents public records — it does not verify or guarantee the accuracy of institutional filings. 13F filings are reported quarterly and may lag actual positions.

Last updated: April 16, 2026 at 06:01 UTC