Stocks are doing something that normally should not happen at the same time.

Major indexes keep closing at record highs even as Treasury yields climb to levels not seen in over two decades. That combination has traditionally meant trouble for expensive growth stocks, not fresh records.

Jim Cramer says there is a clear explanation for the disconnect. It comes down to just three companies carrying far more weight than their size alone would suggest.

Also read: Jim Cramer noticed something odd about the stock market

Cramer says a few stocks are masking the real picture

“Mad Money” host Jim Cramer said Nvidia, Microsoft and Meta are propping up the broader market even as surging Treasury yields pressure nearly everything else on Wall Street. “Here, I think there’s tremendous distortion caused by some very big winners, namely Nvidia, Microsoft and Meta,” he said.

The numbers back up his point. The Nasdaq Composite closed at a fresh record on October 5. Nvidia climbed roughly 2.1 percent to secure its first record close since May. Meta rose about 1.9 percent. Microsoft added 1.5 percent, according to CNBC.

Cramer’s Charitable Trust, the portfolio run by CNBC’s Investing Club, owns shares of all three companies.

Nvidia’s advance pushed its market value to roughly $5.7 trillion, cementing its position as the most valuable public company in the world. Some measures of market breadth remained weak beneath the headline gains, according to Reuters. The S&P 500 also advanced, though it remained just below its own all-time high reached earlier in the year.

Cramer’s broader argument is that this concentration makes the bond market an unusually important signal. If rising yields eventually catch up to even Nvidia, Microsoft and Meta, the record highs could prove far less durable. So much of the recent gains rest on so few names.

Cramer’s framing leaves investors with a fairly direct takeaway. The bond market, not the stock market’s headline numbers, may be the better gauge of underlying risk right now.

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The Treasury yield surge behind the unusual pattern

The yield move underpinning Cramer’s warning has been dramatic. The 10-year Treasury yield climbed to roughly 5.32 percent on October 5. The 30-year yield pushed to around 5.67 percent, according to TheStreet.

That climb has been building for weeks. Just days earlier, the 10-year yield touched its highest level since 2002. The 30-year reached its highest point since July 2002, pushing long-term Treasury yields to levels unseen since before the 2008 financial crisis.

Analysts say the move is not simply about Federal Reserve policy anymore. Elevated real yields, heavy government borrowing and growing competition for capital are combining with a higher term premium. That dynamic goes beyond what a single rate decision could explain.

Even a surprisingly weak jobs report has done little to calm the bond market. September payrolls grew by just 29,000, well below the roughly 90,000 economists expected. That pulled the odds of an October Fed rate hike down sharply.

Yet even with hike odds falling, the 10-year yield remained stubbornly near 5.25 percent. Forces beyond monetary policy are now driving the long end of the curve.

Why concentration in a handful of stocks worries Wall Street

The reliance on so few stocks to carry the market has not gone unnoticed. The four biggest AI spenders, Meta, Microsoft, Amazon and Alphabet, are on track to spend roughly $725 billion on capital expenditure this year. That is up 77 percent from last year’s already record total, according to Yahoo Finance.

That concentration cuts both ways. An investor who has never bought shares of Nvidia or Microsoft may still carry heavy exposure to both through index funds. The market’s apparent strength and its underlying vulnerability are increasingly tied to the same small group of names.

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Nvidia itself is leaning into the moment. Cramer said he is closely watching how the chipmaker trades as it begins executing on its expanded buyback authorization. He reads it as the company using its scale to support its own shares even amid broader market jitters.

Not every part of the AI trade is participating equally. Several stocks and sectors that had previously lagged have struggled even as Nvidia, Microsoft and Meta climbed. Cramer has generally favored established market leaders through this divergence. He has also argued that former leaders can become attractive again after falling behind the broader market.

What investors should watch from here

Cramer’s framing leaves investors with a fairly direct takeaway. The bond market, not the stock market’s headline numbers, may be the better gauge of underlying risk right now.

As long as yields keep climbing, the gains concentrated in a handful of mega-cap names could prove more vulnerable than the record closes suggest.

Several catalysts in the coming days could reshape that picture. Minutes from the Federal Reserve’s September meeting are due. They will offer fresh clues about how officials are weighing persistent inflation against a softening labor market. A fresh mortgage rate reading is already sitting above 7 percent, its highest level in several years.

Until yields show clear signs of stabilizing, Cramer’s message is that investors should watch the bond market closely. The stocks responsible for those record closes represent a narrower slice of the market than the headlines imply.

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