Berkshire Hathaway made significant moves in its portfolio last quarter, notably adding 12 million shares of Sirius XM and nearly 9 million shares of Occidental Petroleum, increasing its stakes to 35% and 28%, respectively. Conversely, it sold over 117 million shares of Bank of America and reduced its holdings in Nu Holdings and Citigroup, reflecting a strategic shift in its banking sector exposure. Despite concerns about market conditions, Buffett continues to invest, maintaining a robust portfolio valued at around $290 billion.