Not every stock in Berkshire Hathaway's portfolio was personally chosen by Warren Buffett, but those he's trusted to make investments follow the same basic principle that helped turn Berkshire into one of the largest companies in the world: Buy good companies with durable competitive advantages at reasonable prices. Many of the stocks in Berkshire's portfolio look like great buys, but others are less appealing. During the first two years of the pandemic, sky-high demand for PCs, electronics, and gadgets triggered a renaissance for the PC industry.