Is This Warren Buffett Stock a Smart Buying Opportunity?

Berkshire Hathaway owns dozens of businesses in its public equities portfolio, with well-known names like Apple, Coca-Cola, and Chevron commanding sizable allocations.But the Oracle of Omaha also likes to own financial services companies. There's one in particular, which the conglomerate has owned since 2011, that might fly under the radar. Is this Warren Buffett stock a smart buying opportunity right now?Tremendous gainsBank of America and American Express get a lot of the attention because they are two to ...