But if they pop: There are only so many trillions that can vanish from portfolios before it triggers a recession.

By Wolf Richter for WOLF STREET.

Trillions of dollars fly by so fast they’re hard to see. By now, 11 US companies have a market value of $1 trillion or more. Combined, they have a market cap of $29 trillion.

Walmart [WMT] was already in the $1 trillion club for a few weeks, if barely, but recently fell off the wagon. If we add Walmart back into it, the 12 US companies have a market cap of $30 trillion – roughly 43% of the total market capitalization of all S&P 500 stocks.

During that little dip from January 28 to March 6 this year, the combined market value of these 12 companies dropped by $1.8 trillion. Over the 58 trading days since then, their combined value jumped by $4.9 trillion. Over the past six years, market value exploded from $6 trillion to $30 trillion. These are generational gains (data via YCharts):

Micron Technology [MU] became the latest entry into that club. Since the low of April 3, 2025, the stock exploded by 1,315%, and its market capitalization exploded from $72 billion to just over $1 trillion. And it did the second half of that trip, from $500 billion to $1 trillion in just 48 trading days, an all-time record — creating another WTF AI Mania Chart.

The 11 US companies in the Trillion Dollar Club:

1. NVIDIA [NVDA]: $5.11 trillion
2. Apple [AAPL]: $4.58 trillion
3. Alphabet [GOOG/GOOGL]: $4.57 trillion
4. Microsoft [MSFT]: $3.34 trillion
5. Amazon [AMZN]: $2.91 trillion
6. Broadcom [AVGO]: $2.12 trillion
7. Tesla [TSLA]: $1.64 trillion
8. Meta Platforms [META]: $1.61 trillion
9. Micron Technology [MU]: $1.09 trillion
10. Eli Lilly [LLY]: $1.04 trillion
11. Berkshire Hathaway [BRK.A/B]: $1.02 trillion
12. Walmart [WMT]: $922 billion

Eli Lilly is threatening to fall off the wagon. It wouldn’t take much for Micron to fall off the wagon either – just a minor day-to-day squiggle would do it. These are volatile stocks at this point.

$30 trillion used to be a huge amount. Not long ago – only four years ago exactly – the entire debt of the US government was $30 trillion. Of course, four years later, it’s $39 trillion. And not because it gained in value, or anything.

There are three other companies with market values of over $1 trillion, but they’re not US companies: chipmakers SK Hynix and Taiwan Semiconductor Manufacturing Company (TSMC) and Saudi Aramco.

Every little dip in market cap of these 12 companies combined represents trillions of dollars of market value vanishing from portfolios without a trace. And every little rally represents trillions of dollars in value being created in portfolios out of nowhere.

If there is even just a 20% dip, God forbid, it would wipe out $6 trillion. $6 trillion in stock market losses used to be some serious money. Now, just another dip by 12 stocks?

A tried-and-true tech selloff in just these top stocks, of the kind we’ve seen before several times after periods of these kinds of generational gains, would… well, whatever else that would do, it would throw the US economy into the recession that people have been feverishly predicting for years.

There are only so many trillions that can vanish from portfolios before it begins to impact economic decision making by consumers and companies alike, and derail economic growth.

That was the case during the 2.5-year-long Dotcom Bust: A year into it, in March 2001, the recession started; and it lasted to November 2001. The Dotcom Bust didn’t bottom out until October 2002, by which time the Nasdaq Composite had collapsed by 78%.

It had shaken up a lot of economic decision making, particularly in areas where internet companies (names that ended with .com), telecom companies, tech hardware and software companies, and biotech companies were densely concentrated, such as Silicon Valley, San Francisco, Seattle, and Boston – they had a depression in those locations.

But the turmoil largely passed by other parts of the country, and the overall recession was pretty mild, compared to the mess that came afterwards which was triggered by the Housing Bubble falling on top of overleveraged and reckless but tightly interconnected banks.

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