Equal-Weight S&P 500 Fund Crosses $100 Billion as Investors Rotate Away From Concentration Risk

The Invesco S&P 500 Equal Weight ETF, ticker RSP, surpassed $100 billion in assets this week, the first time any fund using this approach has reached that threshold, according to data reported by CNBC on August 23.

What happened

RSP has pulled in more than $12 billion in net inflows during 2026 and is up over 13% year to date, compared with roughly 9% for the Vanguard S&P 500 ETF, VOO, the largest fund tracking the standard market-cap-weighted index. RSP holds the same 500 companies as the S&P 500 but assigns each one roughly equal weight instead of weighting by market capitalization, rebalancing every quarter. Launched in 2003, it is the oldest and largest fund using this method.

• RSP assets under management: over $100 billion, a first for an equal-weight fund
• 2026 net inflows: more than $12 billion
• Year-to-date return: RSP +13%, VOO +9% (through August 21)
• Top 10 S&P 500 holdings: roughly 40% of the index's total weight

Why it matters

The gap has one clear driver: concentration. Seven stocks, Alphabet, Amazon, Apple, Meta, Microsoft, Nvidia and Tesla, account for close to a third of the S&P 500's total value. That group was roughly flat in the first half of 2026 while the broader index gained 9.3%. An investor holding a standard S&P 500 fund carries a large, undiversified position in seven companies without ever choosing to.

Equal weighting removes that position. Nathan Geraci, president of NovaDius Wealth Management, said investors have grown more attentive to concentration risk as the performance gap between mega-cap and mid-cap stocks narrows. Cinthia Murphy, director of research at VettaFi, was more direct: "All of a sudden, people are paying attention."

Concentration is often invisible until holdings are aggregated. A single S&P 500 fund looks diversified on a statement. Only a consolidated view across brokers and account types shows that the same seven companies can dominate a portfolio through several different funds at once.

What to watch next

RSP's inflows have accelerated through August, and Invesco has filed for additional equal-weight products tracking other indexes, per ETF.com. If mega-cap technology earnings, including Nvidia's results due August 26, disappoint against high expectations, the rotation into equal-weight strategies could extend. A strong Nvidia print would test whether the shift reflects a lasting change in how investors think about diversification, or a short-term hedge against a handful of expensive stocks.

Portfolio trackers that consolidate holdings across brokers make concentration visible before it becomes a problem, rather than after a single stock or sector reprices sharply.