Microsoft briefly became the world’s most valuable listed company after its 2021 stock rally.
Microsoft overtook Apple by market capitalization in October 2021, helped by strong investor interest in cloud computing and the company’s expanding recurring-revenue businesses. Its shares reached record levels as Azure and other enterprise services grew.
Microsoft began as a software company best known for MS-DOS and Windows, but it later developed major businesses in cloud infrastructure, productivity software, gaming, and professional networking. The transformation made its valuation less dependent on personal-computer sales.
Market-cap leadership can change quickly because it depends on relative share prices. Microsoft and Apple have repeatedly traded places near the top, so a statement about being the largest company usually needs a date and a measurement time.