The Oracle of Omaha just took a $1.6 billion stake in the battered healthcare giant, sending shares soaring 9% after hours.

TheStreet. Warren Buffett is arguably the most successful investor of all time. He's amassed an amazingly massive net worth by buying and usually holding stocks for the long haul. Trained under legendary value fund investor Benjamin Graham,

UnitedHealth shares clocked the largest one-day percent increase since March 2020, as tracked by Dow Jones Market Data Group. It was on pace for the best day in 17 years before giving back some of those gains. For the week, shares rose over 21%, the best week since May 2009. Still, the stock is down more than 50% over the past 12 months.

Warren Buffett's modus operandi is to wait for price dislocations to present themselves. In a historically pricey stock market, locating value has been virtually impossible. Yet, with UnitedHealth Group stock losing more than half its value since the midpoint of April, a rare price dislocation has emerged.

Buffett owned UnitedHealth shares before selling his stake in 2010, though his Berkshire Hathaway recently acquired shares.

Warren Buffett’s Berkshire Hathaway Inc. took new positions in UnitedHealthcare Group Inc. and homebuilder D. R. Horton Inc., and went deeper into other homebuilding and home-related companies, according to a filing late Thursday.

However, Apple is not the only big position that Buffett has been reducing. He also continues to sell down his stake in Bank of America . Buffett sold about 4% of his remaining Ba