IJK vs MDY: Holdings Overlap
IJKiShares S&P Mid-Cap 400 Growth ETF
iShares · 242 holdings · $11.0B · 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 (IJK: 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 IJK and MDY?
iShares S&P Mid-Cap 400 Growth ETF (IJK, by iShares) holds 242 positions; State Street® SPDR® S&P MIDCAP 400® ETF Trust (MDY, by State Street (SPDR)) holds 399. They have 233 holdings in common, and by portfolio weight the two funds are 62.3% identical. In practical terms the pair is heavily overlapping, with largely the same stocks driving both funds.
- Overlap by Weight
- 62.3%Sum of the smaller weight of each shared holding
- Shared Holdings
- 233IJK holds 242 · MDY holds 399
- Weight in Shared Holdings
- IJK 95%·MDY 66%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 IJK
9 of 242 positions (5.2% of the fund) are not held by MDY.
Sector Breakdown
| Sector | IJK | MDY |
|---|---|---|
| Industrials | 31.3% | 25.9% |
| Information Technology | 17.3% | 15.6% |
| Financials | 7.2% | 16.0% |
| Health Care | 14.4% | 10.3% |
| Consumer Discretionary | 10.2% | 11.6% |
| Other Sectors | 19.4% | 25.7% |
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 |
|---|---|---|---|---|---|---|---|
| IJK | +3.1% | +21.4% | +27.9% | +15.9% | +8.4% | +11.3% | 0.52% |
| 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 IJK vs MDY →
Shared Holdings(233)
The top 10 shared positions account for 12% of the overlap, led by ATI, TWLO and FTI.
 ATIATI, Inc. | 1.21% | 0.83% | 0.83% |
|---|---|---|---|
 TWLOTwilio, Inc., Class A | 1.17% | 0.80% | 0.80% |
 FTITechnipFMC plc | 1.71% | 0.76% | 0.76% |
 CRSCarpenter Technology Corporation | 1.20% | 0.76% | 0.76% |
 PEverpure, Inc., Class A | 1.14% | 0.75% | 0.75% |
 NVTnVent Electric plc | 1.17% | 0.72% | 0.72% |
 CWCurtiss-Wright Corporation | 1.54% | 0.72% | 0.72% |
 FIVEFive Below, Inc. | 0.77% | 0.68% | 0.68% |
 OKTAOkta Inc. Class A | 0.82% | 0.66% | 0.66% |
 BURLBurlington Stores, Inc. | 0.76% | 0.64% | 0.64% |
 XPOXPO, Inc. | 1.40% | 0.63% | 0.63% |
 ILMNIllumina, Inc. | 0.62% | 0.80% | 0.62% |
 DYDycom Industries, Inc. | 0.62% | 0.67% | 0.62% |
 UTHRUnited Therapeutics Corporation | 1.57% | 0.62% | 0.62% |
 NYTNew York Times Co. (The), Class A | 0.83% | 0.62% | 0.62% |
 THCTenet Healthcare Corporation | 1.02% | 0.60% | 0.60% |
 WWDWoodward, Inc. | 1.31% | 0.60% | 0.60% |
 MTSIMACOM Technology Solutions Holdings, Inc. | 0.88% | 0.54% | 0.54% |
 MKSIMKS, Inc. | 0.67% | 0.54% | 0.54% |
 FNFabrinet | 1.15% | 0.53% | 0.53% |
 ITTITT, Inc. | 1.00% | 0.52% | 0.52% |
 MOG-AMoog, Inc., Class A | 0.51% | 0.64% | 0.51% |
 RBCRBC Bearings Incorporated | 1.05% | 0.49% | 0.49% |
 RGLDRoyal Gold, Inc. | 1.26% | 0.49% | 0.49% |
 RBARB Global, Inc. | 1.09% | 0.47% | 0.47% |
Frequently Asked Questions
How much do IJK and MDY overlap?
IJK and MDY overlap by 62.3% of portfolio weight. They share 233 holdings (IJK holds 242 positions and MDY holds 399), based on each fund's latest SEC-reported holdings.
Is it redundant to own both IJK and MDY?
The two portfolios are 62.3% identical by weight. Owning both mostly doubles down on the shared core rather than diversifying: the same large positions drive both funds.
What are the biggest shared holdings of IJK and MDY?
The largest positions held by both funds are ATI, TWLO, FTI, CRS and P. Together the top 10 shared positions account for 12% of the total overlap.
What does IJK own that MDY doesn't?
9 positions (5.2% of IJK) are unique to IJK, led by CASY, FLEX and 28T. In the other direction, 166 positions (39.2% of MDY) are unique to MDY.