AIVSX vs VBIAX: 2% overlap
American Funds Investment Company of America A and Vanguard Balanced Index Admiral share 2.2% of their portfolios by weight — computed as Σ min(wA, wB) over every holding both funds own.
You would hold two tickers and get the diversification of 2.0. Two funds that shared nothing would score 2.0; two identical funds score 1.0.
Top shared holdings
AIVSX and VBIAX hold 17 of the same securities. The ten contributing most to the overlap figure:
| Holding | in AIVSX | in VBIAX | Δ |
|---|---|---|---|
| LLY | 3.4% | 0.7% | 2.6% |
| MCD | 0.2% | 0.2% | 0.0% |
| TMO | 0.4% | 0.2% | 0.2% |
| APH | 0.5% | 0.1% | 0.3% |
| MO | 0.3% | 0.1% | 0.2% |
| CME | 0.1% | 0.1% | 0.0% |
| CMCSA | 0.7% | 0.1% | 0.6% |
| AGENCY-MBS | 0.1% | 8.1% | 8.0% |
| T | 0.1% | 0.2% | 0.1% |
| CEG | 0.1% | 0.1% | 0.0% |
Where AIVSX and VBIAX differ
Sector weights as a share of each fund, ordered by the size of the gap rather than the size of the sector — two funds that overlap heavily still usually diverge somewhere.
| Sector | AIVSX | VBIAX | Δ |
|---|---|---|---|
| Unclassified | 5.5% | 55.1% | −49.6pp |
| Information Technology | 29.2% | 1.0% | +28.2pp |
| Treasuries | 0.0% | 19.1% | −19.1pp |
| Industrials | 11.8% | 0.7% | +11.1pp |
| Health Care | 11.2% | 1.2% | +10.1pp |
| Consumer Discretionary | 10.0% | 0.5% | +9.5pp |
| Communication Services | 9.9% | 0.5% | +9.4pp |
| MBS Pass-Through | 0.1% | 8.1% | −8.0pp |
Δ is AIVSX minus VBIAX, in percentage points. Sector data is not published by every issuer, so “Unclassified” is a real category rather than a gap in the table.
What each fund holds alone
92.4% of AIVSX by weight, held in no part of VBIAX.
88.9% of VBIAX by weight, held in no part of AIVSX.
A large count with a small weight is the usual shape: the positions one fund adds are typically its smallest ones.
Concentration and cost
| AIVSX | VBIAX | |
|---|---|---|
| Top 10 holdings | 39.5% | 45.2% |
| Positions held | 168 | 5,119 |
| Cost per $10,000 held, per year | $58 | $7 |
Cost is the expense ratio applied to $10,000; it excludes any brokerage commission, bid-ask spread or tax consequence. Figures are facts about the funds, not a suggestion about which to hold.
Frequently asked
How much do AIVSX and VBIAX overlap?
AIVSX and VBIAX overlap 2.2% by portfolio weight — largely distinct portfolios. They share 17 holdings. The figure comes from current issuer holdings files (AIVSX as of 2026-03-31, VBIAX as of 2026-03-31).
How is the overlap between AIVSX and VBIAX calculated?
As the sum of the smaller weight in each fund, over every holding both funds own: Σ min(wA, wB). If AIVSX holds a stock at 6% and VBIAX holds the same stock at 4%, 4% counts as shared. The result is bounded between 0% and 100%, and it is computed after looking through any fund-of-funds to the underlying holdings.
Is it redundant to hold both AIVSX and VBIAX?
That depends on your goals — we state facts, not advice. At 2.2% overlap, each fund still contributes meaningfully distinct exposure.
What does AIVSX own that VBIAX doesn't?
AIVSX holds 168 positions and VBIAX holds 5,119; 151 of AIVSX's positions don't appear in VBIAX at all, and they are 92.4% of AIVSX by weight.
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Related comparisons
Sources: issuer holdings files, AIVSX as of 2026-03-31, VBIAX as of 2026-03-31. Weights are fractions of each fund. Diagnostics, not advice.