Tech stocks have worst week in months after ‘nobody saw DeepSeek coming’ amid AI mania - MarketWatch
1. DeepSeek's emergence startled investors in AI stocks. 2. Nvidia lost $552 billion in market value this week. 3. Concerns arise over AI chip makers' competitive moats. 4. Tech sector saw its worst week since September. 5. Big Tech's capital spending expected to increase by 25% in 2023.