RSP's $100 billion puts a price on concentration talk

Invesco's RSP, the S&P 500 Equal Weight ETF, crossed $100 billion in assets in mid-August, the first time the fund has reached that level since its 2003 launch, and the firm confirmed the mark Sept. 1. InvestmentNews puts this year's net inflows above $12 billion as investors rotate away from the cap-weighted S&P 500 while the artificial-intelligence-driven mega-cap rally cools.

The construction answers the concentration question plainly: equal slices of roughly 500 constituents instead of market-cap shares, a structure that has outperformed the cap-weighted benchmark by several percentage points this year. Advisors have carried a data line into meetings for months: the top 10 companies now account for roughly 37% to 40% of the index's weight, per S&P Dow Jones Indices. The milestone has turned that chart into a portfolio review.

Matthew Smart, chief investment officer at WWM Investments, told InvestmentNews the milestone matters less than the conversation it forces. Diversification, in Smart's framing, decides which risks remain rather than eliminating risk — 2022 is his standing example, when investors who assumed bonds would cushion their portfolios watched stocks and fixed income fall together. “We want different streams of return and we want to understand exactly where the portfolio's exposures are coming from,” Smart said.

Smart welcomes the market's broadening beyond the Magnificent Seven but stops short of calling it a wholesale rotation out of mega-cap technology, noting that the earnings concentration that was extraordinary in 2023 has spread across more sectors, with estimates extending into 2027. His test for whether the broadening is real is the one he gives clients: “We're trying to make sure a portfolio doesn't require mega-cap leadership to continue in order to succeed.” For clients who do not realize how concentrated they are, the remedy is looking through the full portfolio rather than the fund label.

PWD's Q2 RIA flow data points the same way: demand for semiconductor and AI funds followed the tickers model portfolios already favored, which suggests the equal-weight money may be clearing through the same rails rather than arriving as fresh advisor conviction.

If that is the distribution path, the real test sits in the model portfolios that carried the AI trade into RIA accounts in the first half. Whether RSP appears in those sleeves by year-end will say more about the rotation's durability than the next monthly flow print. Equal weight hedges a specific failure mode — index-level concentration — and nothing else; what the $100 billion measures is how concrete advisors' concentration fears have become.