MDYG vs XBI: Holdings Overlap
MDYGState Street® SPDR® S&P 400™ Mid Cap Growth ETF
State Street (SPDR) · 245 holdings · $2.9B · as of 2026-08-06
XBIState Street® SPDR® S&P® Biotech ETF
State Street (SPDR) · 149 holdings · $10.0B · as of 2026-08-06
How similar are MDYG and XBI?
State Street® SPDR® S&P 400™ Mid Cap Growth ETF (MDYG, by State Street (SPDR)) holds 245 positions; State Street® SPDR® S&P® Biotech ETF (XBI, by State Street (SPDR)) holds 149. They have 9 holdings in common, and by portfolio weight the two funds are 5.3% identical. In practical terms the pair is lightly overlapping, with most of each portfolio distinct.
- Overlap by Weight
- 5.3%Sum of the smaller weight of each shared holding
- Shared Holdings
- 9MDYG holds 245 · XBI holds 149
- Weight in Shared Holdings
- MDYG 6%·XBI 10%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 MDYG
236 of 245 positions (94.3% of the fund) are not held by XBI. Showing the top 30 by weight.
Only in XBI
140 of 149 positions (90.4% of the fund) are not held by MDYG. Showing the top 30 by weight.
Sector Breakdown
| Sector | MDYG | XBI |
|---|---|---|
| Health Care | 15.5% | 95.5% |
| Industrials | 29.8% | 0.0% |
| Information Technology | 20.2% | 0.0% |
| Consumer Discretionary | 9.0% | 0.0% |
| Financials | 8.0% | 0.0% |
| Other Sectors | 17.3% | 0.0% |
| Unclassified | 0.0% | 4.6% |
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. “Unclassified” is weight we could not classify (0% of MDYG, 5% of XBI).
Performance
| Fund | 1M | YTD | 1Y | 3Y (ann.) | 5Y (ann.) | 10Y (ann.) | Yield |
|---|---|---|---|---|---|---|---|
| MDYG | +3.3% | +21.6% | +28.0% | +16.0% | +8.5% | +11.3% | 0.56% |
| XBI | -4.0% | +29.2% | +85.3% | +26.3% | +4.5% | +9.5% | 0.36% |
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 MDYG vs XBI →
Shared Holdings(9)
The top 9 shared positions account for 100% of the overlap, led by UTHR, NBIX and EXEL.
 UTHRUnited Therapeutics Corporation COM | 1.21% | 0.95% | 0.95% |
|---|---|---|---|
 NBIXNeurocrine Biosciences Inc COM | 0.86% | 0.96% | 0.86% |
 EXELExelixis, Inc. COM | 0.70% | 0.96% | 0.70% |
 ARWRArrowhead Pharmaceuticals Inc COM | 0.64% | 1.17% | 0.64% |
 HALOHalozyme Therapeutics Inc COM | 0.54% | 1.18% | 0.54% |
 ROIVRoivant Sciences Ltd SHS | 0.49% | 1.19% | 0.49% |
 KRYSKrystal Biotech Inc COM | 0.45% | 1.00% | 0.45% |
 BMRNBiomarin Pharmaceutical Inc. COM | 0.36% | 1.06% | 0.36% |
 CYTKCytokinetics Incorporated | 0.32% | 1.17% | 0.32% |
Frequently Asked Questions
How much do MDYG and XBI overlap?
MDYG and XBI overlap by 5.3% of portfolio weight. They share 9 holdings (MDYG holds 245 positions and XBI holds 149), based on each fund's latest SEC-reported holdings.
Is it redundant to own both MDYG and XBI?
The two portfolios are 5.3% identical by weight. Owning both is not redundant. Most of each portfolio is distinct, so the funds can serve different roles.
What are the biggest shared holdings of MDYG and XBI?
The largest positions held by both funds are UTHR, NBIX, EXEL, ARWR and HALO. Together the top 9 shared positions account for 100% of the total overlap.
What does MDYG own that XBI doesn't?
236 positions (94.3% of MDYG) are unique to MDYG, led by ATI, TWLO and FTI. In the other direction, 140 positions (90.4% of XBI) are unique to XBI.