DaVita confirmed a ransomware attack exposed data of 2.7M patients, with hackers accessing lab databases. Care at nearly 3,000 clinics and home programs continued, though operations briefly stalled. The attack cost $13.5 mn in Q2, including remediation and patient care expenses. Retail sentiment on Stocktwits turned 'extremely bearish,' worsened by Berkshire Hathaway trimming its stake last month.