The trillion dollar mark is an artificial one for sure. But the market capitalization is a good proxy for the financial power of a company. It's basically what

The trillion dollar mark is an artificial one for sure. But the market capitalization is a good proxy for the financial power of a company. It's basically what the market values the entire company to be worth. If an alien has $1 trillion dollars, it can theoretically buy Apple (if the shareholders are willing to sell, and if the US regulatory agencies would approve the acquisition.)