Last month we learned that Warren Buffett bought shares of American Airlines, Delta Air Lines and United Airlines, according to Berkshire Hathaway’s third-quarter regulatory filings. He also confirmed that he purchased Southwest Airlines stock as well. If we look at the Dow Jones U.S. Airlines Index year-to-date, these allocations appear to have been well-timed.

Buffett Bought at Airline Bottom
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Buffett is universally recognized as one of the most influential investors of all time, so his decision to book a flight on airlines, after blasting the industry for years, is worth examining more closely.

Protected by an Economic Moat

We can mention a couple of things upfront. Most everyone knows Buffett is a value investor. He seeks equity in companies that the market has undervalued—including airlines. As I’ve pointed out before, if we use price-to-earnings as our valuation metric, airlines are among the least expensive in the industrials sector.

He also likes companies that are protected by what he calls a “moat,” the “something” that prevents new competitors from disrupting the industry, giving the veteran players a clear advantage in the marketplace. This is why Buffett has always been attracted to railroads. Because rail is prohibitively capital-intensive, the barriers to entry are high and competition is limited, giving companies greater market power.

Why Buffett Likes Airlines: Protected by a Moat

We see a similar moat protecting U.S. airlines. Since the industry consolidated a decade ago after a wave of bankruptcies, a vast majority of the market share is now concentrated in the big four carriers. In 2015, American, Delta, United and Southwest controlled about 77 percent of U.S. airline revenue.

These are pretty high-level factors to consider. When we delve deeper into the factors Buffett uses to assess equities, the airlines group becomes even more attractive.