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PRIMECAP decreased XNCR position by 456,700 shares

Mar 28, 2026Last updated Apr 16, 2026

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

PRIMECAP MANAGEMENT CO/CA/ AUM: $132.1B DECREASED

AUM: $132.1B · 319 holdings · Period: 2025-12-31

456,700 Share Change

10,218,322 Current Shares

$156.4B Current Value

0.12% Portfolio %

-4.3% Change %

Position Change Detail

Issuer XENCOR INC

Ticker XNCR

Shares 10,675,022 → 10,218,322 456,700

Value $125.2B → $156.4B

Portfolio Weight 0.12%

Change Type Decreased

Period of Report 2025-12-31

Other PRIMECAP Positions This Period

Ticker	Issuer	Change Type	Share Change	Value
WFC	WELLS FARGO CO NEW	Decreased	6,566,583	$779.2B
SONY	SONY GROUP CORP	Decreased	6,140,660	$1492.5B
NWL	NEWELL BRANDS INC	Decreased	5,309,046	$32.4B
OPTU	ALTICE USA INC	Exited	4,869,860	—
MU	MICRON TECHNOLOGY INC	Decreased	4,860,499	$7076.7B
CHV	CHEVRON CORP NEW	Decreased	4,037,474	$354.4B
NFLX	NETFLIX INC	Increased	+3,826,870	$377.2B
ELAN	ELANCO ANIMAL HEALTH INC	Decreased	3,744,068	$1045.8B
INTC	INTEL CORP	Decreased	3,273,242	$2809.3B
AZN	ASTRAZENECA PLC	Decreased	2,942,710	$3393.6B

Other Whales Moving XNCR This Period

Manager	Change Type	Share Change
State Street	Increased	+833,423
Hudson Bay	Increased	+424,997
Two Sigma	Decreased	360,639
Citadel	Decreased	177,978
Renaissance Tech	Decreased	156,231
Acadian	Decreased	120,477
Millennium	Decreased	108,139
Point72	New	+55,339
Marshall Wace	Exited	41,716
Winton	Decreased	37,417

View all sentiment, news, and whale activity for XNCR (XENCOR INC).

Track PRIMECAP and other whale moves in real time on The Wire →

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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