China ? PetroChina Co. became the world’s first company valued at more than a trillion dollars Monday, catapulting over U.S. energy titan Exxon Mobil Corp. as eager Chinese got their first shot at investing in the oil giant when its stock began trading on the Shanghai exchange.

Shares of PetroChina nearly tripled as investors scrambled to get in on the offering of China’s largest oil and gas company. But most of the stock remains in the hands of the state-owned China National Petroleum Corp., and analysts cautioned that Monday’s $1.1 trillion valuation wasn’t directly comparable with the market values of Western companies owned entirely by private investors.

Monday’s IPO raised $8.9 billion, making it the largest ever for China’s mainland market.