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Longleaf Partners increased ACI position by 1,222,843 shares

Mar 28, 2026Last updated Apr 16, 2026

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

SOUTHEASTERN ASSET MANAGEMENT INC/TN/ AUM: $2.2B INCREASED

AUM: $2.2B · 92 holdings · Period: 2025-12-31

+1,222,843 Share Change

5,296,811 Current Shares

$90.9B Current Value

4.05% Portfolio %

+30.0% Change %

Position Change Detail

Issuer ALBERTSONS COS INC

Ticker ACI

Shares 4,073,968 → 5,296,811 +1,222,843

Value $71.3B → $90.9B

Portfolio Weight 4.05%

Change Type Increased

Period of Report 2025-12-31

Other Longleaf Partners Positions This Period

Ticker	Issuer	Change Type	Share Change	Value
RYN	RAYONIER INC	Increased	+1,147,193	$110.2B
AVTR	AVANTOR INC	Decreased	1,143,628	$35.4B
0J7Q	IAC INC	Increased	+1,080,300	$130.6B
ESRT	EMPIRE ST RLTY TR INC	Increased	+1,072,638	$24.1B
PCH	POTLATCHDELTIC CORPORATION	Increased	+955,591	$112.5B
TRIP	TRIPADVISOR INC	Increased	+492,788	$41.3B
SHEN	SHENANDOAH TELECOMMUNICATION	Increased	+491,652	$33.9B
CLW	CLEARWATER PAPER CORP	Increased	+442,386	$24.0B
HTHT	H WORLD GROUP LTD	Decreased	356,629	$10.9B
LPX	LOUISIANA PAC CORP	New	+231,095	$18.7B

Other Whales Moving ACI This Period

Manager	Change Type	Share Change
State Street	Decreased	3,594,865
Invesco	Increased	+3,236,483
Arrowstreet	Increased	+2,519,432
Millennium	Increased	+1,296,200
Renaissance Tech	Exited	1,027,080
GMO	Decreased	879,122
WorldQuant	Decreased	721,778
BlackRock	Decreased	643,203
Gotham Asset	Increased	+626,740
Schonfeld	Increased	+389,578

View all sentiment, news, and whale activity for ACI (ALBERTSONS COS 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