The Globe and Mail reports in its Friday edition that major stock indexes fell sharply on Thursday after Microsoft and Meta Platforms highlighted growing artificial-intelligence costs that could hit their earnings, curbing enthusiasm for megacaps that have fuelled the market rally this year. The Globe's Darcy Keith writes that souring sentiment on Wall Street spread to Canada, where the S&P/TSX Composite Index gave back much of its gain for October. The Toronto market ended down 350.92 points, or 1.43 per cent, at 24,156.87, its lowest closing level since Oct. 8, but still good enough for its fourth straight monthly increase. More turbulence for technology investors erupted after markets closed, when the biggest of the megacaps, Apple, reported quarterly results that included a slump in its net income after paying a one-time charge as part of a tax decision in Europe. Amazon also released its latest earnings after markets closed on Thursday, posting third-quarter profit and sales that beat Wall Street estimates. That sent its shares up 4 per cent after the closing bell, which more than made up for the decline during regular trading. Net income was $15.3-billion (U.S.), up 55 per cent from 2023's $9.9-billion (U.S.).