AMD Just Passed Nvidia at the Top of a $45 Billion Semiconductor ETF. Micron Is Closing In.
As of July 15, AMD surpassed Nvidia as the largest holding in the $45 billion iShares Semiconductor ETF (SOXX), with weights of 8.51% versus 8.35%. This shift reflects AMD's stronger stock momentum since the June rebalance, driven by its 200% annual gain compared to Nvidia's 22%, despite Nvidia's larger market cap. Micron Technology is also rising rapidly, nearing the top three positions.
Nvidia (NVDA 1.97%) is a $5.1 trillion company, roughly six times the size of AMD (AMD 0.66%). But in the $45 billion iShares Semiconductor ETF (SOXX 1.64%), the chipmaker no longer sits on top.
As of July 15, AMD was the fund's largest holding at 8.51% of assets, with Nvidia second at 8.35% and Micron Technology (MU +0.04%) close behind at 7.73%, according to the fund's own holdings data. Broadcom sits fourth at 7.32%, packing the top four into a spread of just over one percentage point. The gaps are thin enough that a single trading day could reorder them.
A year ago, that ordering would have been hard to imagine. Micron traded below $120 per share last July. As of this writing, the stock is up more than 600% over the past 12 months, and AMD has gained more than 200%. Nvidia, over the same stretch, has risen about 22%.
Of course, the fund isn't making a judgment about which company is best. Its math is mechanical. But that math is worth understanding, because it measures where the semiconductor rally's gains have actually landed over the past year.
Image source: Nvidia.
A cap that levels the giants
The exchange-traded fund (ETF) tracks the NYSE Semiconductor Index, which holds the 30 largest U.S.-listed semiconductor companies and weights them by float-adjusted market capitalization -- with a catch. The five largest stocks are capped at 8% of the index when weights are reset, and every other holding at 4%. The index rebalances quarterly, most recently after the third Friday of June.
That cap is arguably the most important thing to understand about the fund. Left to pure market-cap math, Nvidia's $5.1 trillion valuation would run several times the 8% limit and dominate the entire fund. Instead, Nvidia gets pinned at the ceiling alongside anything else that outgrows it. Between resets, weights simply drift with share prices.
NASDAQ: SOXX
Key Data Points
So the top of this fund doesn't rank company size. It ranks share-price momentum since the last reset. AMD's stock has outrun Nvidia's since the June rebalance, and that is the entire reason it now sits on top. Come the index's September reconstitution, anything riding above the cap gets pinned right back at 8%, and the drift starts over.
What the reshuffle actually measures
The reshuffle's real message is in the stock charts -- and in the results behind them.
Micron reported revenue of $41.5 billion for its fiscal third quarter of 2026 (the period ended May 28, 2026), up from $23.9 billion the prior quarter and $9.3 billion in the year-ago period. It was a record quarter, and net income reached $28.2 billion. Micron's high-bandwidth memory (the stacked chips that feed artificial intelligence (AI) accelerators) is at the center of that demand, and its newest generation is already shipping in high volume.
NASDAQ: MU
Key Data Points
"Micron's record fiscal Q3 financial results and even stronger outlook for Q4 reflect the strategic value of memory in the AI era," said CEO Sanjay Mehrotra in the company's fiscal third-quarter earnings release.
AMD's run has a similar shape. First-quarter revenue rose 38% year over year to $10.3 billion, with data center revenue up 57% to $5.8 billion as its Instinct graphics processing units (GPUs) ramp. Management guided for about $11.2 billion of revenue in the second quarter, which would be an acceleration.
NASDAQ: AMD
Key Data Points
And Nvidia? Its business hasn't slowed at all. Revenue for its fiscal first quarter of 2027 (the period ended April 26, 2026) rose 85% year over year to a record $81.6 billion, with data center revenue up 92% to $75.2 billion. The slip in the fund is not a slip in the business.
What changed is everything around Nvidia. A year ago, it was the AI trade. Now the trade has widened -- to the memory makers feeding the data centers and to a second source of AI accelerators -- and the widening shows up as faster stock appreciation everywhere else in the fund.
NASDAQ: NVDA
Key Data Points
For Nvidia shareholders, however, I don't think the demotion is a sell signal. The company just posted 85% growth on record revenue of $81.6 billion. But the leaderboard is a useful reminder that the AI buildout now has more than one way to win, and more than one way to cool.
Sure, Nvidia lost its spot at the top of the fund. But I don't believe the investment case for the stock changed with it.
