Warren Buffett's Berkshire Hathaway posted a record quarterly operating profit of $11.22 billion in the first quarter of this year. The operating profit jumped 39% from $8.07 billion a year earlier. However, the company's net income fell 64% to $12.7 billion. Berkshire also reduced its stake in Apple to $135.4 billion from $174.3 billion at the end of 2023.