Microsoft shares soared more than 15% after the company reported stronger-than-expected fourth-quarter results, with investor enthusiasm centered on continued AI-driven growth. The rally pushed the stock sharply higher in a single session and sent the company’s market capitalization to a new record.

The move was especially notable because it represented the biggest one-day increase in market value ever recorded in the stock market, according to the report. Investors appeared to respond to both the earnings beat and signs that Microsoft’s AI investments are translating into stronger business momentum.

The surge also marked a major shift in sentiment around the stock. Microsoft had trailed some peers for much of the year, making the post-earnings jump stand out even more as traders reassessed the company’s position and growth outlook.

With the latest gain, Microsoft reinforced its standing as one of the market’s most closely watched companies in the AI trade. The results suggested that demand tied to artificial intelligence remains a powerful driver for revenue expectations and for investor confidence in the company’s longer-term growth story.