Warren Buffett’s Berkshire Hathaway revealed a previously confidential holding in UnitedHealth Group, buying 5,039,564 shares during the second quarter, according to a Form 13F filed with the US Securities and Exchange Commission late Thursday. The position was valued at roughly $1.57 billion at the end of June. The filing shows Berkshire continued to reshape its roughly $300 billion equity portfolio. It opened new positions in steelmaker Nucor, homebuilders Lennar and D.R. Horton, billboard operator Lamar Advertising and security-products maker Allegion, while exiting its stake in T-Mobile US and trimming long-standing holdings in Apple and Bank of America. Other high-profile investors also moved into the health-insurance giant. David Tepper’s Appaloosa Management expanded its UnitedHealth stake by about 1,300% to 2.45 million shares worth roughly $665 million, and Michael Burry’s Scion Asset Management reported UnitedHealth stock and call options valued near $115 million. UnitedHealth shares rose more than 7% in post-market trading after the disclosures. Even with the jump, the stock remains about 35% below its average price for the first half of the year, underscoring the steep sell-off that has attracted value-oriented investors.