The shift occurred Monday after Amazon's shares rose 3 per cent to close at USD 1,629.51 and lifted the e-commerce leader's market value to USD 797 billion.
Meanwhile, Microsoft's stock edged up by less than 1 per cent to finish at USD 102.06, leaving the computer software maker's value at USD 784 billion.
If that were to happen, it's likely to slow the growth of companies in technology and other industries that generate a substantial chunk of their revenue outside the US.
That's one reason most technology stocks are well off their peaks. Amazon, for instance, remains 21 per cent below its high reached in September when the company's stock value stood above USD 1 trillion.
Apple was worth even more back then, but its stock has plunged by 37 per cent since early October to erase about USD 400 billion of its market value.
Apple confirmed some of investors' worst fears last week when it warned that disappointing demand for iPhones, especially in China, caused its revenue for its most recent quarter to fall well below the projections of its management and industry analysts.
(This story has not been edited by Business Standard staff and is auto-generated from a syndicated feed.)