A Google cloud logo is seen at the announcement of Google’s biggest-ever investment in Germany on November 11, 2025 in Berlin, Germany.
Sean Gallup | Getty Images News | Getty Images
Alphabet on Monday resuscitated the artificial intelligence trade, which had been flagging the previous week. Its stock jumped 6.3%, lifting associated AI names such as Broadcom, Micron Technology and AMD. Major indexes rallied, with the Nasdaq Composite posting its best day in six months.
Investors were particularly enthusiastic about Broadcom because it helps to design and manufacture Google-parent Alphabet’s custom AI chips. In other words, the more market share Alphabet’s AI offerings gain, the greater the benefit to Broadcom — rather like Nvidia and the broader AI sector at the moment. Broadcom shares surged 11.1% on this notion, making it the S&P 500’s top gainer.
But while investors may cheer Alphabet’s leadership on Monday, not everyone wants it to have the last word.
“Some investors are petrified that Alphabet will win the AI war due to huge improvements in its Gemini AI model and ongoing benefits from its custom TPU chip,” Melius Research analyst Ben Reitzes wrote to clients in a Monday note. “GOOGL winning would actually hurt several stocks we cover — so prepare for volatility.”
Approaching the market’s moves from another angle, Melissa Brown, managing director of investment decision research at SimCorp, said it’s a concern when just one stock lifts the market. “That just doesn’t seem to me to be a sustainable force behind driving the market higher over the next however many days,” she added.
Alphabet on Monday may have brought about alpha — in the sense of market outperformance and potentially beginning a new phase of AI enthusiasm — but letting it be the omega as well could pose problems for investors.
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And finally…
Futures-options traders work on the floor at the New York Stock Exchange’s NYSE American (AMEX) in New York City, U.S., Nov. 19, 2025.
Brendan McDermid | Reuters
Could markets be facing an ‘everything bubble’? Investors are divided
Dan Hanbury, who co-manages the Global Strategic Equity strategy at investment manager Ninety One, told CNBC that while the formation of an AI bubble appears to be “the ultimate question at the moment,” off-kilter prices stretch far beyond the realms of artificial intelligence.
“I think if you step back and look at valuations, it’s very hard to argue there’s not a bubble in the U.S. market,” he conceded. But despite there being “lots of red flags” in equity markets, Hanbury said market participants needed to take a broader view.
— Chloe Taylor