PetroChina briefly reached a $1 trillion market capitalization in 2007.
On November 5, 2007, PetroChina’s shares began trading in Shanghai and briefly gave the company a market value of about $1 trillion. That valuation made PetroChina the world’s most valuable company by market capitalization for a short time, although the price rapidly fell from its opening level.
PetroChina is the listed arm of China National Petroleum Corporation, one of China’s major state-owned energy groups. Its businesses include exploration, production, refining, transportation, and sales of oil and natural gas.
The episode is often discussed as an example of how market capitalization can be distorted by differences between share markets. PetroChina had separate listings in Shanghai and Hong Kong, and the much higher Shanghai price applied to the company’s total share count. The valuation did not mean PetroChina had $1 trillion in cash or assets that could immediately be sold for that amount.