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American Century decreased REGN position by 109,108 shares

Mar 28, 2026Last updated Apr 23, 2026

This StonkWhisper whale intelligence report documents significant institutional position changes in $REGN 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.

AMERICAN CENTURY COMPANIES INC AUM: $199.0B DECREASED

AUM: $199.0B · 2,811 holdings · Period: 2025-12-31

109,108 Share Change

551,487 Current Shares

$425.7B Current Value

0.21% Portfolio %

-16.5% Change %

Position Change Detail

Issuer REGENERON PHARMACEUTICALS

Ticker REGN

Shares 660,595 → 551,487 109,108

Value $371.4B → $425.7B

Portfolio Weight 0.21%

Change Type Decreased

Period of Report 2025-12-31

Other American Century Positions This Period

Ticker	Issuer	Change Type	Share Change	Value
KOS	KOSMOS ENERGY LTD	Decreased	19,075,012	$10.3B
NFLX	NETFLIX INC	Increased	+15,804,792	$1642.0B
KVUE	KENVUE INC	Decreased	10,309,137	$461.2B
T	AT&T INC	Decreased	6,329,511	$98.5B
FNB	F N B CORP	Decreased	5,985,954	$42.8B
GFL	GFL ENVIRONMENTAL INC	Decreased	5,025,075	$42.9B
VICI	VICI PPTYS INC	Decreased	4,649,026	$68.4B
MARA	MARA HOLDINGS INC	Decreased	4,372,799	$2.2B
UAA	UNDER ARMOUR INC	Decreased	3,552,342	$2.3B
APH	AMPHENOL CORP NEW	Increased	+3,437,013	$788.3B

Other Whales Moving REGN This Period

Manager	Change Type	Share Change
AQR Capital	Decreased	692,032
Capital World	Decreased	600,363
Renaissance Tech	Decreased	266,080
Point72	Decreased	200,599
Two Sigma	Decreased	188,752
Bridgewater	Decreased	162,636
Acadian	Decreased	138,710
DE Shaw	Decreased	122,799
LSV	Increased	+110,914
Citadel	Increased	+109,300

View all sentiment, news, and whale activity for REGN (REGENERON PHARMACEUTICALS).

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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 23, 2026 at 06:01 UTC