Berkshire's $1.6B Stake Boosts UnitedHealth to 8th in Trading Volume Amid 0.12% Decline

UnitedHealth (UNH) closed on August 14, 2025, with a 0.12% decline despite a surge in trading activity. The stock recorded a $7.01 billion volume, ranking eighth in the market—a 33.29% increase from the previous day’s volume. This follows a significant development in its ownership structure as Warren Buffett’s Berkshire Hathaway disclosed a new stake in the healthcare giant.

Berkshire Hathaway revealed a second-quarter purchase of over 5 million shares in UnitedHealth, valued at approximately $1.6 billion as of June 30. This positions the insurer as the 18th largest holding in Berkshire’s portfolio, trailing Amazon and Constellation Brands. The move marks Buffett’s return to a sector he previously divested from in 2010 amid regulatory challenges and rising healthcare costs. The investment has drawn attention due to UnitedHealth’s recent struggles, including a 46% year-to-date decline in its stock, federal investigations, and a revised profit forecast signaling billions in additional costs.

The acquisition aligns with Berkshire’s long-term strategy of capitalizing on undervalued assets. While Buffett himself may not have directly oversaw the decision, his investment lieutenants Todd Combs and Ted Weschler are likely responsible. UnitedHealth’s stock briefly surged in after-hours trading following the disclosure, though the broader market context and company-specific risks remain significant headwinds. The insurer continues to face scrutiny over Medicare billing practices and leadership changes, including the resignation of its CEO in May.

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