Microsoft, founded in 1975, briefly became the world’s most valuable publicly traded company in 1999.
Microsoft’s market value surged during the technology boom of the late 1990s. Its dominant Windows operating system and Office productivity software generated powerful recurring demand, while the rapid growth of personal computing increased investor enthusiasm for the company.
Microsoft was founded by Bill Gates and Paul Allen in Albuquerque, New Mexico. It moved its headquarters to the Seattle area as it expanded. By the end of the 1990s, its valuation reflected expectations that software would remain central to business and household computing.
The phrase “most valuable” refers to market capitalization, not revenue or total assets. Microsoft’s ranking changed as technology-stock prices moved, and the dot-com crash soon showed how quickly market valuations could reverse.