Investors who never bought a single Nvidia share still felt Jensen Huang's resignation this week. Nvidia made up 6.39% of State Street's SPDR S&P 500 ETF Trust (SPY) and 6.80% of Invesco QQQ, which tracks the Nasdaq-100, as of Nov. 11, according to the issuers' daily holdings files. In VanEck's Semiconductor ETF (SMH), the share was 17.67%.

Those weights explain why the same piece of news produced very different results across portfolios. Nvidia shares fell as much as 14% on Thursday, Nov. 12, after the company said Huang had stepped down as chief executive, then closed at $166.19, down 4.34%, according to Nasdaq data. Chief Financial Officer Colette Kress is serving as interim CEO while keeping her finance job, The San Francisco Standard reported. For the many investors in Hong Kong, Singapore and across Asia who hold U.S. index funds through brokers or retirement accounts, the question is less about Nvidia itself than about how much of it sits inside the funds they own. Capital Times has covered the stock's swing on Thursday separately.

This article is for education only and is not investment advice.

How much Nvidia is in S&P 500, Nasdaq-100 and MSCI World funds

Index funds that weight companies by market value hold more of the biggest companies. Nvidia, one of the most valuable listed companies in the world, ranks near the top of most broad U.S. and global indexes.

In SPY, the largest S&P 500 tracker, Nvidia was the second-biggest holding on Nov. 11, behind Apple at 7.89% and ahead of Microsoft at 5.89%, the State Street file showed. Other funds that track the S&P 500 hold the index in roughly the same proportions, so the figure is a fair guide for most S&P 500 products.

QQQ held 106 positions on Nov. 11. Nvidia ranked second there too, at 6.80%, behind Apple at 8.43% and ahead of Microsoft at 6.29%, Invesco's data showed. The Nasdaq-100 leaves out financial companies and leans more heavily toward technology, which is why its top names carry slightly bigger weights.

Global funds dilute the exposure. The iShares MSCI World ETF (URTH), which holds 1,250 stocks across developed markets, had 4.42% in Nvidia on Nov. 11, second only to Apple at 5.78%, according to BlackRock's iShares site. Many Asian investors own MSCI World exposure through Ireland-domiciled funds instead, a choice Capital Times explained in its guide to U.S. versus Irish ETFs. Those funds track the same index, so their Nvidia weight should be similar.

Semiconductor ETFs: same theme, very different Nvidia exposure

Sector funds are where the differences grow. SMH, with $64.41 billion in net assets on Nov. 12, held 26 stocks, and Nvidia's 17.67% stake was its biggest, worth about $11.5 billion, VanEck's holdings page showed as of Nov. 11. Taiwan Semiconductor Manufacturing came next at 10.05%, followed by Broadcom at 6.13%.

The iShares Semiconductor ETF (SOXX), with $44.74 billion in net assets, looks similar on paper but is built differently. Its 30 holdings were led by Advanced Micro Devices at 10.23% on Nov. 11. Broadcom held 8.14% and Micron Technology 7.37%. Nvidia ranked fourth at 6.90%, according to iShares. SOXX's 6.90% stake in Nvidia was less than half of SMH's, though both funds are sold as chip-sector ETFs.

The gap matters on a day like Thursday, when Nvidia fell while some rivals rose. SOXX's net asset value slipped just 0.26% on Nov. 12, iShares data showed.

What the drop means in dollars

A simple rule of thumb: a fund's loss from one stock roughly equals the stock's move multiplied by its weight in the fund. The calculation ignores what every other holding did that day, so it shows Nvidia's contribution, not the fund's actual return.

Using Thursday's 4.34% decline and the Nov. 11 weights, Nvidia alone would have cut about 0.28 percentage point from an S&P 500 fund, or roughly $28 on a $10,000 holding, by Capital Times' calculation. The hit works out to about $30 in QQQ and SOXX, $19 in an MSCI World fund and $77 in SMH. At Thursday's intraday low, when Nvidia was down about 14%, the drag on SMH from Nvidia alone would have been close to 2.5%.

Those figures look small for broad funds, but the exposure is concentrated. Mark Malek, chief investment officer at Siebert Financial, said Nvidia's succession risk becomes a portfolio risk for millions of investors, The San Francisco Standard reported. Investors who own both an S&P 500 fund and a technology or chip fund often hold more Nvidia than they realize, because the stock appears in each one.

Holdings also shift daily as prices move, so weights after Thursday's drop will be slightly lower than the Nov. 11 figures. Issuers publish updated files on their fund pages each business day, which is the most reliable way to check exposure.

The next test for index investors comes on Nov. 17, when Nvidia reports quarterly results with Kress as interim chief executive.