PetroChina was the first company to reach a $1 trillion market capitalization during its 2007 stock-market debut.
PetroChina reached the landmark on November 5, 2007, when its Shanghai-listed shares surged on their first day of trading. The company was valued at more than $1 trillion intraday, making it briefly the world's most valuable publicly traded company by market capitalization.
The valuation did not remain at that level for long. PetroChina's shares later declined substantially, illustrating why a debut-day market cap and a sustained valuation are different things. The company is the listed oil and gas arm of China National Petroleum Corporation, one of China's major state-owned energy groups.
This record is often overlooked because Apple later made the $1 trillion milestone famous in the United States. Apple's 2018 achievement was the first sustained $1 trillion valuation for a U.S. company, not the first time any listed company had touched the level.