KEY POINTS There are plenty of great Buffett stocks, including Apple, Amazon, Chevron, Bank of America, and Mastercard. Markel is sort of a "baby Berkshire" and provides diversification with its equity holdings. Markel has underperformed in recent years, but is doing well in 2022 and is valued attractively. This stock offers something that none of Berkshire's other holdings can.Don't underestimate the power of $Berkshire Hathaway(BRK.A)$($Berkshire Hathaway(BRK.B)$) 13F-HR filing to the U.S. Securities and Exchange Commission (SEC). The SEC requires the company to disclose all of the stocks that it owns on a quarterly basis.In a real sense, Berkshire's 13F-HR provides a peek into what Warren Buffett