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.

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

Blackrock’s spot bitcoin exchange-traded fund is having its worst month ever as its underlying asset suffers its largest monthly decline in more than three years.

The iShares Bitcoin Trust ETF has recorded $2.2 billion in outflows this month, as of Monday, FactSet data shows. That’s nearly eight times the $291 million in losses suffered by the investment vehicle last October, or its second-worst month on record since its debut in early 2024. 

The outflows come as bitcoin is bleeding. The digital asset was last trading at $87,907.10 — down more than 20% over the past month and off more than 40% from its high of just north of $126,000 hit in early October. That makes November bitcoin’s worst month since June 2022, when the asset’s price fell about 39%.

“There’s no doubt that hot-money investments have had significant outflows,” Jay Hatfield, CEO and portfolio manager at Infrastructure Capital Advisors, told CNBC.

But, “the pullback is really focused on the gambling part of the market … and bitcoin is really the poster child for that,” he said. 

Investors are exiting Blackrock’s fund to rotate into risk-off assets such as gold amid mounting economic uncertainties and signs of souring market sentiment.

A recent survey from the University of Michigan showed that consumer sentiment has nosedived to near record-low levels. Meanwhile, investors are awaiting crucial data from the September retail sales and the producer price index reports, due out on Tuesday. And while the CME FedWatch Tool shows that traders are now pricing in more than 80% odds that the Federal Reserve will slash rates at its December meeting, such a cut remains far from sure bet.

Amid all the uncertainty, bitcoin is bleeding. And, investors in spot bitcoin ETFs, particularly newer holders, are feeling pressure to sell their shares — a reality that could extend the asset’s downside in the near term, Frank Chaparro, head of content and special projects at crypto-focused trading firm GSR, told CNBC. 

“With the macro environment becoming less certain, investors tend to de-risk across assets, which often means trimming exposure to crypto and other risk-sensitive stocks,” Chaparro said. “And for newer entrants who came in through the funds, any downturn can be unsettling – they can sell just as quickly as they bought.”

But while it’s true that spot bitcoin ETFs have brought in hoards of new retail investors who may be flighty during volatile times, the funds have also attracted a range of long-term investors such as institutions who can hold through the downturn, according to Joshua Levine, chairman at bitcoin treasury firm OranjeBTC, told CNBC. 

That institutional base could “dampen some of the extreme downside, but also smooth upside, reducing bitcoin’s volatility as the asset class matures,” Levine said. 

Shares of flash storage vendor Sandisk popped 7% in extended trading on Monday after the company was added to S&P 500.

Sandisk’s addition to the benchmark comes nine months after the company was spun out of Western Digital. Sandisk will replace marketing company Interpublic, which is being acquired by Omnicom, S&P Global said in a statement.

It’s the latest tech company to join the S&P 500, which gets an increasing amount of its value from internet, software and semiconductor businesses. AppLovin, Datadog, DoorDash and Robinhood became members of the index earlier this year.

Stocks tend to rally when they’re added to the benchmark as fund managers who track the S&P 500 need to buy shares to reflect the changes.

Western Digital bought Sandisk in 2016 for $15.6 billion. In February, Western Digital spun out its flash business as Sandisk, which now has a market cap of about $33 billion.

Sandisk sells fast storage drives for gaming PCs, digital cameras and security cameras, and is also trying to land deals with large-scale data center builders. Revenue in the latest quarter rose 23% to $2.31 billion. The company reported a 31% increase in exabytes sold.

Omnicom announced plans to acquire Interpublic in December, and on Monday said the deal received antitrust approval from the European Commission.

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