One major exception came from Alphabet, which finished up 3.5%, passing Microsoft to become the world’s third-largest company. Until recently, Google-parent Alphabet was seen as an AI laggard, with more to lose from the new technology than gain. Alphabet has a rich source of funds in its massive advertising business, while rival OpenAI is likely to need more debt, stock issuance, and other creative forms of financing to pay for its AI models.