Amazon became the second U.S. company to reach a $1 trillion market capitalization in September 2018, after Apple.
Amazon crossed the threshold on September 4, 2018, when its share price rose above the level required to value the company at $1 trillion. Apple had reached the milestone about one month earlier. The event showed how investors valued Amazon’s combination of online retail, logistics, cloud computing, and subscription services.
Amazon began as an online bookseller founded by Jeff Bezos in 1994, but it expanded into a broad technology and commerce company. Amazon Web Services became especially important because cloud computing generated substantial revenue and operating profit.
The phrase “second U.S. company” is narrower than “second company worldwide,” because companies outside the United States had also reached very high valuations. Market capitalization is calculated by multiplying a company’s share price by its outstanding shares, so the ranking can change daily.