In this articleDVABRK.AFollow your favorite stocksCREATE FREE ACCOUNTTraders work on the floor of the New York Stock Exchange on Feb. 13, 2025. NYSEDaVita, a company that provides dialysis services, saw shares tumbling Friday after issuing a weak outlook amid rising care costs, while big investor Berkshire Hathaway offloaded some shares in a preplanned agreement.The health-care stock fell 8% in premarket trading Friday. The Colorado-based company said it expects its 2025 adjusted profit per share to be between $10.20 and $11.30, compared to analysts’ average expectation of $11.24 per share, according to LSEG.The disappointing guidance underlined increasing patient care costs due to center closure costs and health benefit expenses. In the fourth quarter, the company incurred charges for closures of its dialysis centers in the U.S. totaling $24.2 million.Still, DaVita’s fourth-quarter earnings of $2.24 per share on an adjusted basis topped analysts’ estimates of $2.13 per share per LSEG.Loading chart…Separately, DaVita’s largest institutional investor Berkshire Hathaway sold 203,091 shares on Tuesday to reduce its stake to 45%, worth nearly $6.4 billion, a regulatory filing Thursday night showed.The sale was part of a share repurchase agreement the two parties reached back in April. DaVita agreed to buy back shares to reduce Berkshire’s ownership stake to 45% on a quarterly basis.Warren Buffett’s conglomerate first invested in DaVita in 2011. As of the end of September, DaVita was Berkshire’s 10th largest equity holding.Don’t miss these insights from CNBC PRODon’t expect a 20% S&P 500 three-peat this year, Wells Fargo saysBlackRock’s Rick Rieder thinks this corner of the bond market is too cheap to ignoreThe ‘clock is ticking’ on stalled stock market to make a move or break down, says chart analystAnalysts speculate selling by Buffett could be behind recent Bank of America weaknessJPMorgan manager says his $39 billion ETF can profit from volatility in 2025 — and it yields 7% …