IVW vs MDY: 0% overlap
iShares S&P 500 Growth ETF and SPDR S&P MidCap 400 ETF Trust share 0.0% of their portfolios by weight — computed as Σ min(wA, wB) over every holding both funds own.
You would hold two tickers and get the diversification of 2.0. Two funds that shared nothing would score 2.0; two identical funds score 1.0.
Top shared holdings
IVW and MDY hold 0 of the same securities. The ten contributing most to the overlap figure:
| Holding | in IVW | in MDY | Δ |
|---|
Where IVW and MDY differ
Sector weights as a share of each fund, ordered by the size of the gap rather than the size of the sector — two funds that overlap heavily still usually diverge somewhere.
| Sector | IVW | MDY | Δ |
|---|---|---|---|
| Information Technology | 52.5% | 13.8% | +38.7pp |
| Industrials | 6.6% | 25.4% | −18.7pp |
| Communication Services | 14.7% | 1.5% | +13.2pp |
| Real Estate | 0.7% | 6.9% | −6.2pp |
| Financials | 9.2% | 14.8% | −5.7pp |
| Materials | 0.3% | 5.4% | −5.1pp |
| Energy | 0.0% | 4.9% | −4.9pp |
| Health Care | 6.3% | 9.7% | −3.4pp |
Δ is IVW minus MDY, in percentage points. Sector data is not published by every issuer, so “Unclassified” is a real category rather than a gap in the table.
What each fund holds alone
100.0% of IVW by weight, held in no part of MDY.
98.9% of MDY by weight, held in no part of IVW.
A large count with a small weight is the usual shape: the positions one fund adds are typically its smallest ones.
Concentration and cost
| IVW | MDY | |
|---|---|---|
| Top 10 holdings | 58.2% | 7.6% |
| Positions held | 149 | 400 |
| Cost per $10,000 held, per year | $18 | $23 |
Cost is the expense ratio applied to $10,000; it excludes any brokerage commission, bid-ask spread or tax consequence. Figures are facts about the funds, not a suggestion about which to hold.
Frequently asked
How much do IVW and MDY overlap?
IVW and MDY overlap 0.0% by portfolio weight — largely distinct portfolios. They share 0 holdings. The figure comes from current issuer holdings files (IVW as of 2026-07-23, MDY as of 2026-07-23).
How is the overlap between IVW and MDY calculated?
As the sum of the smaller weight in each fund, over every holding both funds own: Σ min(wA, wB). If IVW holds a stock at 6% and MDY holds the same stock at 4%, 4% counts as shared. The result is bounded between 0% and 100%, and it is computed after looking through any fund-of-funds to the underlying holdings.
Is it redundant to hold both IVW and MDY?
That depends on your goals — we state facts, not advice. At 0.0% overlap, each fund still contributes meaningfully distinct exposure.
What does IVW own that MDY doesn't?
IVW holds 149 positions and MDY holds 400; 148 of IVW's positions don't appear in MDY at all, and they are 100.0% of IVW by weight.
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Related comparisons
Sources: issuer holdings files, IVW as of 2026-07-23, MDY as of 2026-07-23. Weights are fractions of each fund. Diagnostics, not advice.