VB vs XBI: how much do they overlap?
Vanguard Small-Cap ETF (VB) · SPDR S&P Biotech ETF (XBI)
overlap by weight · 51 shared holdings
VB: 1312 holdings (as of 2026-03-31) · XBI: 149 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.
Low overlap
What this means
VB and XBI hold mostly different stocks. Combining them genuinely spreads your exposure across different parts of the market.
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 VB | in XBI |
|---|---|---|---|
| Natera Inc | NTRA | 0.37% | 1.16% |
| United Therapeutics Corp | UTHR | 0.36% | 0.91% |
| REVOLUTION Medicines Inc | RVMD | 0.26% | 1.18% |
| Moderna Inc | MRNA | 0.25% | 1.49% |
| Insmed Inc | INSM | 0.25% | 1.15% |
| Incyte Corp | INCY | 0.22% | 1% |
| Neurocrine Biosciences Inc | NBIX | 0.19% | 1% |
| Bridgebio Pharma Inc | BBIO | 0.18% | 1.2% |
| Roivant Sciences Ltd | ROIV | 0.18% | 1.16% |
| Ionis Pharmaceuticals Inc | IONS | 0.17% | 0.78% |
FAQ
How much do VB and XBI overlap?
VB and XBI have a 4.8% overlap by weight, sharing 51 holdings (out of 1312 in VB and 149 in XBI), based on official issuer holdings as of 2026-03-31.
What does 4.8% overlap mean?
VB and XBI hold mostly different stocks. Combining them genuinely spreads your exposure across different parts of the market.
Which stocks do VB and XBI both hold?
The largest shared positions are Natera Inc, United Therapeutics Corp, REVOLUTION Medicines Inc, Moderna Inc, Insmed Inc. The full list of top shared holdings with weights in each fund is shown on this page.