Sector ETFs are sold as an easy way to buy an entire industry in a single trade — a diversified basket that spares investors from having to pick individual winners. In reality, because most of these funds are market-cap-weighted, a tiny cluster of mega-cap stocks often dominates the portfolio, gutting the diversification that investors expect.
Latest holdings data from State Street reveal that the worst concentration is not found in the heavily scrutinized technology sector, but in consumer discretionary, communication services, and energy. Three stocks control well over 40% of each of those funds, making them far more concentrated than many realize.
| Sector | Ticker | Top 3 Holdings | Combined Weight |
| Consumer Discretionary | XLY | Amazon, Tesla, Home Depot | 44.7% |
| Communication Services | XLC | Alphabet, Meta, AT&T | 43.0% |
| Energy | XLE | ExxonMobil, Chevron, ConocoPhillips | 42.1% |
| Technology | XLK | Nvidia, Apple, Microsoft | 35.2% |
| Healthcare | XLV | Eli Lilly, Johnson & Johnson, AbbVie | 34.3% |
| Financials | XLF | JPMorgan Chase, Berkshire Hathaway, Visa | 30.8% |
| Utilities | XLU | NextEra Energy, Southern Company, Duke Energy | 27.8% |
| Real Estate | XLRE | Welltower, Prologis, Equinix | 27.0% |
| Consumer Staples | XLP | Walmart, Costco, Procter & Gamble | 26.7% |
| Materials | XLB | Linde, Newmont, Freeport-McMoRan | 25.3% |
| Industrials | XLI | Caterpillar, GE Aerospace, RTX | 18.6% |
Source: State Street, ranked by combined weight of top 3 holdings in descending order.
The Consumer Discretionary Select Sector SPDR (XLY) is the most extreme case. Amazon, Tesla, and Home Depot together account for 44.7% of the portfolio. Amazon and Tesla alone command roughly 40%, meaning the fund’s returns are overwhelmingly driven by just two names. The Communication Services Select Sector SPDR (XLC) is a similar story: Alphabet, Meta Platforms, and AT&T combine for a 43% weight. AT&T contributes only about five percentage points; Meta and Alphabet together soak up close to 40%. The Energy Select Sector SPDR (XLE) is likewise built around two giants — ExxonMobil and Chevron claim 35% of the fund, while the top three holdings, which also include ConocoPhillips, reach 42.1%.
Technology, despite grabbing headlines for its top-heavy nature, only ranks fourth. The Technology Select Sector SPDR (XLK) has Nvidia, Apple, and Microsoft at a combined 35.2%. Adding Broadcom lifts the top four to roughly 40%, still milder than the three sectors ahead of it. Healthcare (XLV) follows with Eli Lilly, Johnson & Johnson, and AbbVie at 34.3%, while Financials (XLF) sits at 30.8% via JPMorgan Chase, Berkshire Hathaway, and Visa.
Concentration then steps down across the remaining sectors. Utilities (XLU), real estate (XLRE), consumer staples (XLP), and materials (XLB) all see their top three holdings land between 25% and 28%. The sole fund that offers a genuinely spread-out structure is Industrials (XLI), where Caterpillar, GE Aerospace, and RTX account for just 18.6% of assets.
The structural flaw is the same across the board: a few dominant names carry disproportionate influence, distorting the sector exposure investors actually receive. For those who want true industry diversification, Invesco’s suite of equal-weighted sector ETFs provides a direct alternative — same constituent companies, but without the concentration risk embedded in traditional market-cap-weighted funds.
