Berkshire Hathaway, under the investment guidance of Warren Buffett, has periodically acquired and divested equity stakes in major global pharmaceutical corporations, adjusting its portfolio holdings based on long-term valuation assessments and sector stability. While historical filings revealed strategic investments in prominent drug manufacturers like Johnson & Johnson, Pfizer, and Merck, subsequent quarterly portfolio adjustments reflect dynamic asset reallocation strategies typical of the conglomerate's disciplined investment philosophy.