Data as of Sep 12, 2026. Both funds on the fields they both publish, from the same sources.
IBB vs VBK: how they differ
IBB and VBK hold 11% of their weight in the same names, and IBB returned more over the year.
iShares Biotechnology ETF and Vanguard Small-Cap Growth Index Fund.
What they hold in common
By the books each fund has filed, IBB and VBK hold 11% of their money in the same securities at the same weight.
| Holding | IBB | VBK |
|---|---|---|
| Revolution Medicines, Inc. | 2.78% | 1.07% |
| Natera, Inc. | 2.89% | 1.04% |
| Incyte Corp. | 1.75% | 0.54% |
| Neurocrine Biosciences, Inc. | 1.30% | 0.48% |
| Bridgebio Pharma, Inc. | 0.98% | 0.37% |
| Exelixis, Inc. | 1.03% | 0.37% |
| Illumina, Inc. | 2.07% | 0.36% |
| Ionis Pharmaceuticals, Inc. | 1.00% | 0.35% |
| Medpace Holdings, Inc. | 0.95% | 0.34% |
| Cytokinetics, Inc. | 0.79% | 0.33% |
| Insmed, Inc. | 1.79% | 0.33% |
| United Therapeutics Corp. | 1.74% | 0.32% |
| Only in IBB | Only in VBK |
|---|---|
| Vertex Pharmaceuticals, Inc. 8.09% | Credo Technology Group Holding Ltd 1.27% |
| Amgen, Inc. 7.84% | Astera Labs Inc 1.05% |
| Gilead Sciences, Inc. 6.85% | Twilio Inc 0.88% |
| Regeneron Pharmaceuticals, Inc. 4.91% | Casey's General Stores Inc 0.83% |
| Argenx SE 3.76% | Carpenter Technology Corp 0.82% |
| Alnylam Pharmaceuticals, Inc. 3.12% | Curtiss-Wright Corp 0.79% |
| Biogen, Inc. 2.47% | FTAI Aviation Ltd 0.78% |
| Moderna, Inc. 1.99% | nVent Electric PLC 0.77% |
Weight overlap is an ETFIQ calculation: for every security both funds hold, the smaller of the two weights, summed. Above 50%, holding both is close to holding one of them twice. Holdings dated Jun 30, 2026.
| IBB iShares Biotechnology ETF | VBK Vanguard Small-Cap Growth Index Fund | |
|---|---|---|
| Where it sits | Core index fund | Core index fund |
| Issuer | iShares | Vanguard |
| What it is | Biotechnology | Small-Cap Growth |
| Total return, 1 year | +41.5% | +13.8% |
| S&P 500 over the same days | +17.5% | +17.5% |
| Gap to the S&P 500 | +24.0 pts | −3.7 pts |
| Expense ratio | 0.44% | 0.05% |
| Already in the S&P 500 | 35.6% | 10.2% |
| Holdings | 248 | 545 |
IBB in plain words
IBB is an index equity fund tracking the Biotechnology. Over the year to Sep 11, 2026 it returned +41.5% with distributions reinvested, against +17.5% for the S&P 500 and +23.0% for the Nasdaq-100. The prospectus expense ratio is 0.44% a year. By its holdings filed for Jun 30, 2026, 36% of the fund by weight is stocks the S&P 500 also holds, across 248 positions, with the top ten at 44.8%. It sat 6.5% below its high of Aug 19, 2026 on Sep 11, 2026.
VBK in plain words
VBK is an index equity fund tracking the Small-Cap Growth. Over the year to Sep 11, 2026 it returned +13.8% with distributions reinvested, against +17.5% for the S&P 500 and +23.0% for the Nasdaq-100. The prospectus expense ratio is 0.05% a year. By its holdings filed for Jun 30, 2026, 10% of the fund by weight is stocks the S&P 500 also holds, across 545 positions, with the top ten at 9.3%. It sat 7.0% below its high of Aug 17, 2026 on Sep 11, 2026.
Questions people ask
- Which returned more over the last year, IBB or VBK?
- In the year to Sep 12, 2026, with distributions reinvested, IBB returned +41.5% and VBK returned +13.8%, so IBB returned more. One year is one year; the longer windows are in the table.
- Which is cheaper, IBB or VBK?
- IBB charges 0.44% a year and VBK charges 0.05%, so VBK is cheaper. Fees come from each fund's prospectus.
- How much do IBB and VBK overlap with the S&P 500?
- By their latest filed holdings, 36% of IBB and 10% of VBK by weight is stocks the S&P 500 already holds. Between the two funds, 11% of their books are the same securities at the same weight.
Other comparisons
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Where these figures came from
ETFIQ links to the documents behind every figure. It is not affiliated with any issuer, and a link is not an endorsement.
Cite this page. ETFIQ, IBB against VBK, data as of Sep 12, 2026. https://etfiq.com/compare/any/IBB-VBK Free to use with attribution; the underlying files are at Open data.
A comparison is not a recommendation. Standards and sources