IWF vs MDY: Holdings Overlap
IWFiShares Russell 1000 Growth ETF
iShares · 387 holdings · $127.3B · as of 2026-03-31
MDYState Street® SPDR® S&P MIDCAP 400® ETF Trust
State Street (SPDR) · 399 holdings · $27.1B · as of 2026-08-06
Holdings snapshots are 128 days apart (IWF: 2026-03-31, MDY: 2026-08-06). Weights and index membership change between snapshots, so the true current overlap is typically higher than shown. For funds tracking the same index, the gap can be 5–15 points.
How similar are IWF and MDY?
iShares Russell 1000 Growth ETF (IWF, by iShares) holds 387 positions; State Street® SPDR® S&P MIDCAP 400® ETF Trust (MDY, by State Street (SPDR)) holds 399. They have 95 holdings in common, and by portfolio weight the two funds are 1.5% identical. In practical terms the pair is essentially distinct, holding almost none of the same securities.
- Overlap by Weight
- 1.5%Sum of the smaller weight of each shared holding
- Shared Holdings
- 95IWF holds 387 · MDY holds 399
- Weight in Shared Holdings
- IWF 1%·MDY 27%Share of each fund's weight in stocks both funds own
Based on each fund's latest official holdings. How is this calculated?
What makes each fund different
Only in IWF
292 of 387 positions (98.4% of the fund) are not held by MDY. Showing the top 30 by weight.
Sector Breakdown
| Sector | IWF | MDY |
|---|---|---|
| Information Technology | 49.2% | 15.6% |
| Industrials | 6.7% | 25.9% |
| Financials | 5.9% | 16.0% |
| Consumer Discretionary | 13.1% | 11.6% |
| Communication Services | 12.4% | 2.2% |
| Other Sectors | 12.5% | 33.7% |
Share of each fund's portfolio weight by GICS-style sector, compiled from issuer fund data and our own classification of the holdings, not the issuers' published sector charts.
Performance
| Fund | 1M | YTD | 1Y | 3Y (ann.) | 5Y (ann.) | 10Y (ann.) | Yield |
|---|---|---|---|---|---|---|---|
| IWF | +2.7% | +5.5% | +13.1% | +22.0% | +12.6% | +17.8% | 0.35% |
| MDY | +3.1% | +18.1% | +25.6% | +14.2% | +8.8% | +10.9% | 0.99% |
Total returns including dividends, from adjusted daily closes as of 2026-08-07. 3Y/5Y/10Y are annualized. Yield is trailing-12-month distributions over the last close. Past performance does not predict future results.
Project the growth of $10,000 in IWF vs MDY →
Shared Holdings(95)
The top 10 shared positions account for 32% of the overlap, led by BURL, P and SGI.
 BURLBurlington Stores Inc. COM | 0.07% | 0.64% | 0.07% |
|---|---|---|---|
 PEverpure, Inc., Class A | 0.06% | 0.75% | 0.06% |
 SGISomnigroup International Inc. COM | 0.05% | 0.37% | 0.05% |
 GWREGuidewire Software Inc COM | 0.05% | 0.37% | 0.05% |
 PENPenumbra Inc. COM | 0.04% | 0.35% | 0.04% |
 TOSTToast, Inc., Class A | 0.04% | 0.45% | 0.04% |
 NBIXNeurocrine Biosciences Inc COM | 0.04% | 0.44% | 0.04% |
 TXRHTexas Roadhouse Inc COM | 0.04% | 0.37% | 0.04% |
 DTDynatrace Inc COM NEW | 0.04% | 0.39% | 0.04% |
 LSCCLattice Semiconductor Corporation COM | 0.04% | 0.48% | 0.04% |
 MEDPMedpace Holdings Inc. COM | 0.04% | 0.36% | 0.04% |
 EQHEquitable Holdings Inc COM | 0.04% | 0.40% | 0.04% |
 BAHBooz Allen Hamilton Holding Corporation Class A | 0.03% | 0.24% | 0.03% |
 EXELExelixis, Inc. COM | 0.03% | 0.36% | 0.03% |
 MUSAMurphy USA Inc. COM | 0.03% | 0.25% | 0.03% |
 CAVACAVA Group Inc. COM | 0.03% | 0.17% | 0.03% |
 MANHManhattan Associates Inc COM | 0.03% | 0.31% | 0.03% |
 KNSLKinsale Capital Group Inc COM | 0.03% | 0.23% | 0.03% |
 SFMSprouts Farmers Markets Inc COM | 0.03% | 0.22% | 0.03% |
 HALOHalozyme Therapeutics Inc COM | 0.03% | 0.28% | 0.03% |
 DOCUDocusign, Inc., Class A | 0.03% | 0.30% | 0.03% |
 PLNTPlanet Fitness, Inc., Class A | 0.02% | 0.11% | 0.02% |
 BROSDutch Bros, Inc., Class A | 0.02% | 0.19% | 0.02% |
 CHWYChewy, Inc., Class A | 0.02% | 0.15% | 0.02% |
 CELHCelsius Holdings Inc. COM NEW | 0.02% | 0.10% | 0.02% |
Frequently Asked Questions
How much do IWF and MDY overlap?
IWF and MDY overlap by 1.5% of portfolio weight. They share 95 holdings (IWF holds 387 positions and MDY holds 399), based on each fund's latest SEC-reported holdings.
Is it redundant to own both IWF and MDY?
The two portfolios are 1.5% identical by weight. Owning both is genuine diversification: the funds hold almost none of the same securities.
What are the biggest shared holdings of IWF and MDY?
The largest positions held by both funds are BURL, P, SGI, GWRE and PEN. Together the top 10 shared positions account for 32% of the total overlap.
What does IWF own that MDY doesn't?
292 positions (98.4% of IWF) are unique to IWF, led by NVDA, AAPL and MSFT. In the other direction, 304 positions (77.7% of MDY) are unique to MDY.