Southeastern Asset Management (Longleaf)

Superinvestor

Southeastern Asset Management Inc

SEC CIK: 0000807985
Manager: Mason Hawkins
Style: Value
Latest filing: Aug 14, 2026

SEC filings (opens in a new tab)

WTM holding history

White Mountains Insurance Group Ltd in every 13F filed by Southeastern Asset Management (Longleaf), including the quarters it was sold out or no filing was made. Changes compare share counts with the previous calendar quarter.

WTM overview All 13F holders of WTM Full Q2 2026 holdings

Shares (Q2 2026): 17,104
Value: $35.5M
% of portfolio: 1.8%
Quarters held: 19; Since Q4 2021

Holdings of WTM by Southeastern Asset Management (Longleaf), by quarter
Quarter	Shares	Value	% of portfolio	Share change	Action	All holders
Q2 2026	17,104	$35.5M	1.8%	−1,760−9.3%	Reduced	Holders
Q1 2026	18,864	$41.4M	2.0%	−12,788−40.4%	Reduced	Holders
Q4 2025	31,652	$65.8M	2.9%	00.0%	Unchanged	Holders
Q3 2025	31,652	$52.9M	2.7%	+10,558+50.1%	Added	Holders
Q2 2025	21,094	$37.9M	1.9%	+2,610+14.1%	Added	Holders
Q1 2025	18,484	$35.6M	1.9%	−760−3.9%	Reduced	Holders
Q4 2024	19,244	$37.4M	1.8%	−1,494−7.2%	Reduced	Holders
Q3 2024	20,738	$35.2K	<0.1%	−685−3.2%	Reduced	Holders
Q2 2024	21,423	$38.9M	1.7%	−3,285−13.3%	Reduced	Holders
Q1 2024	24,708	$44.3M	1.7%	−7,738−23.8%	Reduced	Holders
Q4 2023	32,446	$48.8M	1.9%	−499−1.5%	Reduced	Holders
Q3 2023	32,945	$49.3M	1.8%	−9,272−22.0%	Reduced	Holders
Q2 2023	42,217	$58.6M	2.1%	−11,316−21.1%	Reduced	Holders
Q1 2023	53,533	$73.7M	2.5%	−1,960−3.5%	Reduced	Holders
Q4 2022	55,493	$78.5M	2.8%	−57,104−50.7%	Reduced	Holders
Q3 2022	112,597	$146.7M	3.7%	−13,006−10.4%	Reduced	Holders
Q2 2022	125,603	$156.5M	3.3%	+100+0.1%	Added	Holders
Q1 2022	125,503	$142.6M	2.5%	+73,901+143.2%	Added	Holders
Q4 2021	51,602	$52.3M	0.9%	+51,602	New	Holders