Berkshire Agrees to Limit Stake in DaVita to 25%
Berkshire also agreed not to push for board seats or seek to buy the company or engage in proxy fights with the company.
Berkshire is already DaVita's largest shareholder with a stake of about 13 percent.
But this isn't a Warren Buffett investment. Ted Weschler, who joined Berkshire in early 2012 as a portfolio manager, has been buying DaVita shares and signed the agreement.