IWD vs MDY: how much do they overlap?
iShares Russell 1000 Value ETF (IWD) · SPDR S&P MIDCAP 400 ETF Trust (MDY)
overlap by weight · 270 shared holdings
IWD: 866 holdings (as of 2026-03-31) · MDY: 400 holdings (as of 09-Jul-2026)
Note: the two funds' latest official filings have different dates, which can understate overlap slightly for funds tracking similar indexes.
Low overlap
What this means
IWD and MDY hold mostly different stocks. Combining them genuinely spreads your exposure across different parts of the market.
Overlap by weight sums the smaller of the two funds' weights for every stock they both hold — it answers "how much of my money is in the same stocks either way?" See methodology.
Top shared holdings
| Company | Ticker | in IWD | in MDY |
|---|---|---|---|
| TECHNIPFMC PLC | FTI | 0.09% | 0.78% |
| UNITED THERAPEUTICS CORPORATION | UTHR | 0.08% | 0.65% |
| CURTISS-WRIGHT CORPORATION | CW | 0.08% | 0.78% |
| WOODWARD, INC. | WWD | 0.07% | 0.67% |
| ROYAL GOLD, INC. | RGLD | 0.07% | 0.45% |
| US FOODS HOLDING CORP. | USFD | 0.07% | 0.61% |
| ATI INC | ATI | 0.06% | 0.71% |
| ILLUMINA, INC. | ILMN | 0.06% | 0.81% |
| NVENT ELECTRIC PUBLIC LIMITED COMPANY | NVT | 0.06% | 0.71% |
| XPO, INC. | XPO | 0.06% | 0.68% |
FAQ
How much do IWD and MDY overlap?
IWD and MDY have a 7.1% overlap by weight, sharing 270 holdings (out of 866 in IWD and 400 in MDY), based on official issuer holdings as of 2026-03-31.
What does 7.1% overlap mean?
IWD and MDY hold mostly different stocks. Combining them genuinely spreads your exposure across different parts of the market.
Which stocks do IWD and MDY both hold?
The largest shared positions are TECHNIPFMC PLC, UNITED THERAPEUTICS CORPORATION, CURTISS-WRIGHT CORPORATION, WOODWARD, INC., ROYAL GOLD, INC.. The full list of top shared holdings with weights in each fund is shown on this page.