Most valuable companies in history, adjusted for inflation

When Apple surpassed Exxon-Mobil as the world’s most valuable company in August 2012, it ignited a debate over what, precisely, “most valuable” means--and how inflation influences the calculation. Apple’s 2012 market valuation topped out at $661 billion U.S., the highest absolute-value figure in history, but a longer-term view of other corporate giants shows it has a ways to go before it can claim the all-time, inflation-adjusted top prize. Here are history's 9 most valuable companies, adjusted for inflation.

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9. Exxon-Mobil in 2007
Value then: $513.3 billion // Adjusted to 2012 dollars: U.S. $572.9 billion

HOW IT GOT SO BIG: Exxon-Mobil is the energy industry’s poster child for growth by acquisition. The most outsized product of a decades-long energy industry consolidation trend, the 1999 merger closed a loop first opened in 1911 with the government-imposed breakup of Standard Oil. The two companies that resulted, Jersey Standard and Socony, ultimately... more
9. Exxon-Mobil in 2007
Value then: $513.3 billion // Adjusted to 2012 dollars: U.S. $572.9 billion

HOW IT GOT SO BIG: Exxon-Mobil is the energy industry’s poster child for growth by acquisition. The most outsized product of a decades-long energy industry consolidation trend, the 1999 merger closed a loop first opened in 1911 with the government-imposed breakup of Standard Oil. The two companies that resulted, Jersey Standard and Socony, ultimately evolved into Exxon and Mobil. The combined organization topped the charts thanks to broad reserves, consistent production growth, and the runup in global energy indices.

WHAT’S HAPPENED SINCE: Its star has faded somewhat as oil prices have subsided from historic highs. But it hasn’t mis-stepped so much as remained vulnerable to volatile commodity pricing.

VALUE TODAY: $421 billion (#2 on current NASDAQ rankings)

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