PetroChina became the world’s most valuable public company in 2007 after its stock-market debut.
PetroChina’s shares began trading in Shanghai in November 2007, and the company’s value briefly rose above US$1 trillion on its first day. The surge made it the world’s largest public company by market capitalization at that moment, although the valuation quickly fell as trading conditions changed.
PetroChina is the publicly listed arm of China National Petroleum Corporation, one of China’s major state-owned energy groups. Its business includes exploration, production, refining, chemicals, and natural-gas operations.
This episode is a reminder that market-cap records can be short-lived. A first-day price spike does not necessarily represent a stable long-term ranking, and PetroChina’s later position differed substantially from its debut-day peak.