Fund · State Street(R) SPDR(R) S&P(R) Biotech ETF · measured from SEC filings
XBI holdings
XBI reports 158 holdings and behaves like 110.2 equally weighted ones, computed from its SEC Form N-PORT filing for 2026-06-30. The fact sheet publishes the first number; this page computes the second, and traces it across 28 quarters of filings.
Measured concentration
as of 2026-06-30Read this figure with the following in mind
5.9% of net assets is securities-lending cash collateral, excluded from the figure; counted as filed the fund would read 79.8
The figure below is what the filing says, published unchanged. What it may not do is sit beside a plain long-only fund and be read as the same quantity. How comparability is decided.
Computed by this site from the fund's SEC Form N-PORT filing; what the measure does not tell you · every fund in one table · hold it with other funds? X-ray the mix. Pricing: 99.9% at a quoted market price (level 1), 7 issuer countries.
What stands out
as of 2026-06-30XBI's largest investment is Apogee Therapeutics Inc at 1.49% of net assets. Moderna Inc and Twist Bioscience Corp follow; the three together are 4.31%. Ten companies are 13.32% of the fund; the other 148 share the rest. Among the 721 equity funds measured here, XBI behaves like 110.2 holdings against a median of 42.4 — 2.6 times the median. Across 28 quarterly filings XBI has become less concentrated: it behaved like 82.2 at 2019-09-30 and 110.2 at 2026-06-30. Between the 2026-03-31 and 2026-06-30 filings 13 positions were added and 11 dropped; 13.2% of the weight moved.
Each sentence is read from the fund's own SEC filing; the class median is computed across the comparable equity funds on this site. Nothing here is a view on the fund.
Every filing since 2019
28Between 2019-09-30 and 2026-06-30, XBI went from behaving like 82.2 equally weighted positions to 110.2 — 34% more, while its top ten went from 17.73% to 13.32% of net assets. Read across the funds on the concentration-over-time table.
| Period | Holdings | Effective | Top 10 | Largest |
|---|---|---|---|---|
| 2026-06-30 | 158 | 110.2 | 13.32% | 1.49% |
| 2026-03-31 | 155 | 106.5 | 13.66% | 1.83% |
| 2025-12-31 | 153 | 102.8 | 13.51% | 1.49% |
| 2025-09-30 | 134 | 77.2 | 19.48% | 2.26% |
| 2025-06-30 | 127 | 63.5 | 24.96% | 2.66% |
| 2025-03-31 | 127 | 64.2 | 26.04% | 2.88% |
| 2024-12-31 | 142 | 69.3 | 23.69% | 2.56% |
| 2024-09-30 | 144 | 66.1 | 25.73% | 2.67% |
Earlier filings (20 more, back to 2019-09-30)
| Period | Holdings | Effective | Top 10 | Largest |
|---|---|---|---|---|
| 2024-06-30 | 140 | 61.9 | 28.33% | 3.31% |
| 2024-03-31 | 137 | 116.6 | 10.92% | 1.16% |
| 2023-12-31 | 123 | 92.1 | 16.12% | 2.78% |
| 2023-09-30 | 135 | 101.9 | 13.96% | 1.66% |
| 2023-06-30 | 141 | 112.5 | 11.71% | 1.27% |
| 2023-03-31 | 148 | 120.4 | 11.2% | 1.29% |
| 2022-12-31 | 154 | 110.4 | 14.06% | 3.66% |
| 2022-09-30 | 155 | 123.3 | 11.27% | 1.39% |
| 2022-06-30 | 136 | 106.7 | 13.42% | 1.48% |
| 2022-03-31 | 158 | 126.9 | 10.62% | 1.16% |
| 2021-12-31 | 190 | 146.1 | 9.82% | 1.44% |
| 2021-09-30 | 189 | 158.3 | 8.63% | 0.99% |
| 2021-06-30 | 199 | 174.4 | 8.63% | 1.18% |
| 2021-03-31 | 193 | 172.1 | 7.64% | 0.84% |
| 2020-12-31 | 172 | 131.3 | 10.89% | 1.17% |
| 2020-09-30 | 143 | 112.3 | 13.18% | 1.87% |
| 2020-06-30 | 135 | 105.4 | 14.34% | 2.03% |
| 2020-03-31 | 124 | 73.1 | 23.22% | 2.77% |
| 2019-12-31 | 127 | 83.9 | 17.45% | 1.92% |
| 2019-09-30 | 119 | 82.2 | 17.73% | 2.09% |
One row per filed reporting period, newest first, read from EDGAR. Quarterly because that is the public filing cadence. Rows marked * are published but held out of the comparison above; the methodology page says when and why.
Compared with, in the essays
1Overlap with other funds
1Measured against every other fund on this site, from the same filings. Combined effective holdings is how the pair behaves held in equal size.
| With | Overlap | Shared | Combined effective |
|---|---|---|---|
| XBI vs IBB | 41.57% | 123 | 75.1 |
As filed, collateral included
5.87% collateralXBI's filing lists 159 positions including 5.87% of net assets in securities-lending cash collateral. Counted as filed the fund reads 79.8 effective holdings with a top ten of 17.99%; on its own investments — the figure above — it reads 110.2 with a top ten of 13.32%. The collateral is matched by a liability and is not a holding the fund chose; since 2026-09-18 every figure on this site sets it aside (methodology). Both numbers are in the data.
Largest positions, as filed
as of 2026-06-30The 15 largest of 158 positions in XBI's Form N-PORT, weight as a share of net assets, securities-lending collateral excluded. Every position, every quarter: XBI.csv.gz.
| # | Position | Weight | Cumulative |
|---|---|---|---|
| 1 | Apogee Therapeutics Inc | 1.49% | 1.5% |
| 2 | Moderna Inc | 1.41% | 2.9% |
| 3 | Twist Bioscience Corp | 1.41% | 4.3% |
| 4 | Oruka Therapeutics Inc | 1.38% | 5.7% |
| 5 | Kymera Therapeutics Inc | 1.36% | 7.0% |
| 6 | Viking Therapeutics Inc | 1.30% | 8.4% |
| 7 | Praxis Precision Medicines Inc | 1.29% | 9.6% |
| 8 | Erasca Inc | 1.27% | 10.9% |
| 9 | Revolution Medicines Inc | 1.20% | 12.1% |
| 10 | Rhythm Pharmaceuticals Inc | 1.20% | 13.3% |
| 11 | CG oncology Inc | 1.20% | 14.5% |
| 12 | SELLAS Life Sciences Group Inc | 1.19% | 15.7% |
| 13 | Vaxcyte Inc | 1.19% | 16.9% |
| 14 | Dianthus Therapeutics Inc | 1.18% | 18.1% |
| 15 | Cytokinetics Inc | 1.18% | 19.3% |
By country of issuer
as of 2026-06-30Share of XBI's own investments by the issuer country the filer reported (incorporation, not revenue). Each country links to every fund that holds it.
| Country | Share |
|---|---|
| United States | 94.86% |
| Ireland° | 1.24% |
| Bermuda° | 1.16% |
| Netherlands° | 1.03% |
| Switzerland | 1.02% |
| British Virgin Islands° | 0.53% |
| Canada | 0.16% |
Returns the fund reported
2019-07 – 2026-06Monthly total returns from Item B.5 of XBI's own filings, 84 months on record. Not computed here and not from a price feed.
Cross-checked against a series computed separately from prices: median difference 0.07 percentage points over 84 months, which is roughly the distributions. Every month with the filing it came from: XBI.json · all funds.
Who borrows XBI's shares
2026-06-30The fund lends its holdings, and Item B.4.a of the filing names every firm holding them. At 2026-06-30, $1.2bn was out to 24 borrowers, 11.63% of net assets. The largest, BARCLAYS BANK PLC, held 43.3% of it.
| Borrower | On loan | Share of the loan |
|---|---|---|
| BARCLAYS BANK PLC | $541m | 43.3% |
| BofA Securities, Inc. | $172m | 13.8% |
| JP MORGAN SECURITIES LLC | $114m | 9.2% |
| MORGAN STANLEY & CO LLC | $81m | 6.5% |
| GOLDMAN SACHS & CO. | $57m | 4.6% |
Cash collateral reported against the loan: 5.87% of net assets, 50.5% of the amount lent. That is a floor on the collateral, not the whole of it — collateral the fund does not hold as a position is not in this filing, so a figure under 100% is not evidence of under-collateralisation. How that figure behaves across all funds. Every quarter XBI has filed, with each borrower: XBI.json · all funds.
Since the previous filing
2026-03-31 → 2026-06-30154 positions became 156: 13 added (2.1% of the fund at the later date), 11 dropped (5.9% at the earlier date). Half the sum of all weight changes, a turnover proxy: 13.2%. Positions are matched on identifiers, so a security whose identifier changed shows as one drop and one add. Every filing of XBI compared this way, as a feed: changes.xml · all funds: filings received.
| Largest increases | 2026-03-31 | 2026-06-30 | Largest decreases | 2026-03-31 | 2026-06-30 |
|---|---|---|---|---|---|
| SELLAS Life Sciences Group Inc | 0.27% | 1.19% | Arcutis Biotherapeutics Inc | 1.09% | 0.71% |
| Oruka Therapeutics Inc | 0.50% | 1.38% | Alkermes PLC | 1.45% | 1.11% |
| Relay Therapeutics Inc | 0.38% | 1.10% | Madrigal Pharmaceuticals Inc | 1.38% | 1.06% |
| uniQure NV | 0.37% | 1.03% | United Therapeutics Corp | 1.24% | 0.92% |
| Dianthus Therapeutics Inc | 0.66% | 1.18% | Immunome Inc | 0.86% | 0.59% |
| Absci Corp | 0.18% | 0.56% | Ardelyx Inc | 0.62% | 0.35% |
New: Avalo Therapeutics Inc (0.35%), Jade Biosciences Inc (0.32%), Solid Biosciences Inc (0.24%), Immix Biopharma Inc (0.20%), Candel Therapeutics Inc (0.19%), First Tracks Biotherapeutics Inc (0.17%). Gone: Apellis Pharmaceuticals Inc (1.83%), Amicus Therapeutics Inc (1.15%), Arcellx Inc (1.14%), Soleno Therapeutics Inc (0.67%), Day One Biopharmaceuticals Inc (0.32%), KalVista Pharmaceuticals Inc (0.29%).
Asset categories and pricing
as of 2026-06-30| Asset category (as filed) | Share of investments |
|---|---|
| equity EC | 94.31% |
| short-term investment STIV | 5.59% |
| derivative DE | 0.10% |
99.9% of XBI is carried at a quoted market price (fair-value level 1). Categories and levels are the filer's, from Form N-PORT; what a low level-1 share does and does not mean is in the measure's page.
Neighbours by effective holdings, equity funds
10Every measured equity fund lined up by how many holdings it behaves like; these sit either side of XBI (110.2). Same filings, same arithmetic. Position in this list says nothing about which fund is better.
| Fund | Reports | Behaves like | Top ten | As of |
|---|---|---|---|---|
| FEM First Trust Emerging Markets AlphaDEX Fund | 153 | 104.8 | 18.43% | 2026-06-30 |
| DOL WisdomTree True Developed International Fund | 301 | 105.9 | 20.01% | 2026-06-30 |
| DSPY Tema S&P 500 Historical Weight ETF Strategy | 504 | 107.1 | 22.79% | 2026-05-31 |
| XSVM Invesco S&P SmallCap Value with Momentum ETF | 119 | 107.7 | 15.15% | 2026-07-31 |
| AUSF Global X Adaptive U.S. Factor ETF | 195 | 109.9 | 16.76% | 2026-05-31 |
| USMV iShares MSCI USA Min Vol Factor ETF | 168 | 110.5 | 15.14% | 2026-07-31 |
| DTD WisdomTree U.S. Total Dividend Fund | 823 | 113.4 | 21.04% | 2026-06-30 |
| FCTR First Trust Lunt U.S. Factor Rotation ETF | 166 | 113.9 | 18.11% | 2026-06-30 |
| DBEU Xtrackers MSCI Europe Hedged Equity ETF | 429 | 114.1 | 20.52% | 2026-05-29 |
| ACWI iShares MSCI ACWI ETF | 2,268 | 114.3 | 24.13% | 2026-07-31 |
Essays that examine XBI
1-
XBI vs IBB: Equal-Weight vs Cap-Weight Biotech — Two Very Different Risk Profiles
XBI weights biotech names roughly equally, tilting hard toward small- and mid-cap clinical-stage companies; IBB is cap-weighted and dominated by a handful...
Mentions are detected across the full text of every article, so an appearance may be a passing comparison rather than the subject. Nothing here is a recommendation to buy or sell — see the disclaimer.