MTUM Investors: Watch Micron’s Weight at the November Reconstitution

The iShares MSCI USA Momentum Factor ETF (MTUM) has run hard this year, climbing 30% year to date and 38% over the past 12 months to roughly $326. Headline numbers, though, mask a violent rotation inside MTUM’s portfolio. The AI/cloud mega-caps that powered the momentum trade through 2025 have stumbled, while one AI-memory name has gained traction.

Details

According to a report from 24/7 Wall St., the upcoming November reconstitution of the MTUM ETF could see a significant increase in the weight of Micron Technology (MU). Micron, a memory chipmaker, has benefited from surging demand for high-bandwidth memory (HBM) used in AI processors. While shares of Microsoft (MSFT), Apple (AAPL), and Alphabet (GOOGL) have pulled back from highs, Micron has maintained its upward momentum.

Context

MTUM tracks the MSCI USA Momentum Factor Index, which selects stocks based on past performance. As the November reconstitution approaches, Micron’s weight in the fund is likely to increase if it continues to outperform. Conversely, mega-cap tech stocks may see their weights reduced if their momentum fades.

What This Means for Investors

MTUM investors should closely monitor the November reconstitution, as a higher Micron weight could boost the fund’s performance if the stock continues its rally. However, momentum strategies carry risks, especially if a stock’s trend reverses. This article does not constitute a buy or sell recommendation.