Magnificent Seven Share of S&P 500: 30.8% and a $1 Trillion Day

The Magnificent Seven share of the S&P 500 is close to a third of the index. Six of the seven, Nvidia, Apple, Microsoft, Alphabet, Amazon and Meta, made up 30.8% of the S&P 500 as of November 2, 2026, according to The Motley Fool, and that count leaves out Tesla. The index's 10 largest companies held 39%, up from about 36.4% two years earlier.

So is the market more concentrated than at the dot-com peak? By the top-10 measure, yes, and by a wide margin. The harder question is what that concentration does to risk, and Thursday, November 5, gave a live answer: the seven lost more than $1 trillion in market value in one session, and Nvidia alone accounted for more than $440 billion of it, CNBC reported.

30.8%

Six Mag 7 stocks' S&P 500 weight, Nov 2

39%

Top 10 stocks' share of the index

26.6%

Top 10 share at the tech bubble peak

$440B+

Nvidia's market value lost on Nov 5

Six stocks, almost a third of the index

Apple is now the largest company in the S&P 500 at a 7.2% weight, just ahead of Nvidia at 7.1%, according to The Motley Fool's figures as of November 2. Microsoft follows at 5.5%, Alphabet at 4.9%, Amazon at 3.9% and Meta at 2.3%. Every dollar put into an S&P 500 index fund therefore sends about 31 cents to these six companies, before Tesla is counted.

Many trackers quote a figure for all seven that sits several points higher once Tesla is added. We could not confirm a current all-seven number from a primary source, so we use the six-stock figure here. Either way, the group is large enough that its daily moves set the direction of the whole index on most days.

The total barely moved in two years, the mix did

The surprise in the data is how stable the total has been. The same six stocks made up about 30.2% of the S&P 500 in October 2024, The Motley Fool calculated, against 30.8% now. Underneath that flat line, money moved between them.

Alphabet gained the most weight, helped by a stock that rose about 63% over two years. Of the four with published figures, Microsoft lost the most, as its shares rose about 23.6% over the same stretch, behind the market. Meta, up about 7% in two years, slipped. The group is less a single block than it looks: the six share an AI story but not the same results.

An equal-weighted basket of all seven, the Roundhill Magnificent Seven ETF, returned 41.9% over two years against 31.7% for an S&P 500 fund. The group still beat the market, but three of the six large names trailed it.

What concentration looked like on November 5

Concentration cuts both ways. On Thursday the Nasdaq Composite fell more than 5% and the S&P 500 more than 4%, their worst days since April 4, 2025, CNBC and IBTimes reported. The S&P 500 technology sector fell 7.30%, its worst day since March 16, 2020. Nvidia dropped more than 9% and finished the day down 2.6% for the year.

The damage did not stay with the giants. After the session, 174 stocks in the S&P 500, or 34.6%, were at least 20% below their 52-week highs, and 61.6% were at least 10% below, according to the same CNBC data. When the largest names carry the index on the way up, a sharp drop in them can hide how many other stocks were already weak. We covered the session in AI Stocks Crash: Chip Index Falls 12%.

More concentrated than the dot-com peak

The top 10 stocks held 40.8% of S&P 500 market value in May 2026, J.P. Morgan Asset Management strategists Meera Pandit and Corey Hill wrote, well above the 26.6% peak of the tech bubble. The Motley Fool's November figure of 39% suggests the share has eased only slightly since. Measures differ by provider and date, so treat the bars below as a range, not a precise series.

Weight is only half the picture. J.P. Morgan noted that the top 10 earn just over one third of the index's profits, so their size is backed by a large share of real earnings, and it put their valuation at about 26 times earnings, 25% above their long-term average. How that compares with the leaders of 2000 is laid out in our dot-com bubble vs AI bubble comparison and the dot-com bubble timeline. Concentration this high means index investors carry more single-company risk than at any point in that era; it does not by itself mean those companies are overvalued.

What the AI Bubble Index says about concentration

The AI Bubble Index read 63.9 after Friday's close, in its Normal band, up from 62.9 a week earlier. Concentration is measured inside its valuation and concentration family, which read 57.9, down from 70.4 on October 6 as AI stocks fell from their highs. The sentiment and attention family, at 92.5, is the most stretched part of the index, while the demand gap is the coolest at 40.1.

The index has drifted down from 68.5 in early October to the low 60s, and it rose slightly on Thursday and Friday despite the selloff; it weighs many inputs beyond a single day's prices. The full methodology is on the methodology page, and our guide to Magnificent Seven stocks and concentration risk explains why a few names can dominate an index without the whole market being in a bubble.