IJH vs MDY: how much do they overlap?
iShares Core S&P Mid-Cap ETF (IJH) · SPDR S&P MIDCAP 400 ETF Trust (MDY)
overlap by weight · 388 shared holdings
IJH: 399 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.
High overlap
What this means
IJH and MDY are largely the same portfolio. Holding both adds little diversification — most dollars end up in the same underlying stocks.
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 IJH | in MDY |
|---|---|---|---|
| TechnipFMC PLC | FTI | 0.87% | 0.78% |
| Curtiss-Wright Corp. | CW | 0.78% | 0.78% |
| XPO Inc | XPO | 0.71% | 0.68% |
| Woodward Inc. | WWD | 0.67% | 0.67% |
| United Therapeutics Corporation | UTHR | 0.8% | 0.65% |
| ATI Inc | ATI | 0.62% | 0.71% |
| Mastec, Inc. | MTZ | 0.62% | 0.66% |
| Carpenter Technology Corporation | CRS | 0.61% | 0.82% |
| US Foods Holding Corp | USFD | 0.63% | 0.61% |
| NVent Electric PLC | NVT | 0.6% | 0.71% |
FAQ
How much do IJH and MDY overlap?
IJH and MDY have a 89.2% overlap by weight, sharing 388 holdings (out of 399 in IJH and 400 in MDY), based on official issuer holdings as of 2026-03-31.
What does 89.2% overlap mean?
IJH and MDY are largely the same portfolio. Holding both adds little diversification — most dollars end up in the same underlying stocks.
Which stocks do IJH and MDY both hold?
The largest shared positions are TechnipFMC PLC, Curtiss-Wright Corp., XPO Inc, Woodward Inc., United Therapeutics Corporation. The full list of top shared holdings with weights in each fund is shown on this page.