Data as of Sep 12, 2026. Both funds on the fields they both publish, from the same sources.
MGK vs XBI: how they differ
MGK and XBI hold 1% of their weight in the same names, and XBI returned more over the year.
Vanguard Mega Cap Growth Index Fund and State Street(R) SPDR(R) S&P(R) Biotech ETF.
What they hold in common
By the books each fund has filed, MGK and XBI hold 1% of their money in the same securities at the same weight.
| Holding | MGK | XBI |
|---|---|---|
| Vertex Pharmaceuticals Inc | 0.60% | 1.06% |
| Only in MGK | Only in XBI |
|---|---|
| NVIDIA Corp 13.29% | Apogee Therapeutics Inc 1.49% |
| Apple Inc 12.19% | Moderna Inc 1.41% |
| Microsoft Corp 7.52% | Twist Bioscience Corp 1.41% |
| Alphabet Inc 5.93% | Oruka Therapeutics Inc 1.38% |
| Alphabet Inc 4.67% | Kymera Therapeutics Inc 1.36% |
| Amazon.com Inc 4.47% | Viking Therapeutics Inc 1.31% |
| Broadcom Inc 4.28% | Praxis Precision Medicines Inc 1.29% |
| Meta Platforms Inc 4.08% | Erasca Inc 1.27% |
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.
| MGK Vanguard Mega Cap Growth Index Fund | XBI State Street(R) SPDR(R) S&P(R) Biotech ETF | |
|---|---|---|
| Where it sits | Core index fund | Core index fund |
| Issuer | Vanguard | State Street |
| What it is | Mega Cap Growth | SPDR S&P Biotech |
| Total return, 1 year | +14.9% | +64.0% |
| S&P 500 over the same days | +17.5% | +17.5% |
| Gap to the S&P 500 | −2.6 pts | +46.5 pts |
| Expense ratio | 0.07% | 0.35% |
| Already in the S&P 500 | 99.2% | 8.5% |
| Holdings | 56 | 150 |
MGK in plain words
MGK is an index equity fund tracking the Mega Cap Growth. Over the year to Sep 11, 2026 it returned +14.9% with distributions reinvested, against +17.5% for the S&P 500 and +23.0% for the Nasdaq-100. The prospectus expense ratio is 0.07% a year. By its holdings filed for Jun 30, 2026, 99% of the fund by weight is stocks the S&P 500 also holds, across 56 positions, with the top ten at 63.8%.
XBI in plain words
XBI is an index equity fund tracking the SPDR S&P Biotech. Over the year to Sep 11, 2026 it returned +64.0% with distributions reinvested, against +17.5% for the S&P 500 and +23.0% for the Nasdaq-100. The prospectus expense ratio is 0.35% a year. By its holdings filed for Jun 30, 2026, 8% of the fund by weight is stocks the S&P 500 also holds, across 150 positions, with the top ten at 13.3%. It sat 9.6% below its high of Feb 8, 2021 on Sep 11, 2026.
Questions people ask
- Which returned more over the last year, MGK or XBI?
- In the year to Sep 12, 2026, with distributions reinvested, MGK returned +14.9% and XBI returned +64.0%, so XBI returned more. One year is one year; the longer windows are in the table.
- Which is cheaper, MGK or XBI?
- MGK charges 0.07% a year and XBI charges 0.35%, so MGK is cheaper. Fees come from each fund's prospectus.
- How much do MGK and XBI overlap with the S&P 500?
- By their latest filed holdings, 99% of MGK and 8% of XBI by weight is stocks the S&P 500 already holds. Between the two funds, 1% of their books are the same securities at the same weight.
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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, MGK against XBI, data as of Sep 12, 2026. https://etfiq.com/compare/any/MGK-XBI Free to use with attribution; the underlying files are at Open data.
A comparison is not a recommendation. Standards and sources