AIVSX vs FXNAX: 0% overlap
American Funds Investment Company of America A and Fidelity U.S. Bond Index share 0.2% of their portfolios by weight — computed as Σ min(wA, wB) over every holding both funds own.
Different holding dates. These holdings were published 31 days apart — FXNAX as of 2026-02-28, the rest through 2026-03-31. Each fund is compared using its most recent file, so any trading in between shows up as a difference.
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 FXNAX hold 2 of the same securities. The ten contributing most to the overlap figure:
| Holding | in AIVSX | in FXNAX | Δ |
|---|---|---|---|
| AGENCY-MBS | 0.1% | 16.5% | 16.4% |
| CASH | 0.1% | 1.3% | 1.3% |
Where AIVSX and FXNAX 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 | FXNAX | Δ |
|---|---|---|---|
| Treasuries | 0.0% | 45.4% | −45.4pp |
| Information Technology | 29.2% | 0.0% | +29.2pp |
| MBS Pass-Through | 0.1% | 16.5% | −16.4pp |
| Corporate — industrial & other | 0.0% | 14.1% | −14.1pp |
| Industrials | 11.8% | 0.0% | +11.8pp |
| Health Care | 11.2% | 0.0% | +11.2pp |
| Consumer Discretionary | 10.0% | 0.0% | +10.0pp |
| Communication Services | 9.9% | 0.0% | +9.9pp |
Δ is AIVSX minus FXNAX, 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
100.1% of AIVSX by weight, held in no part of FXNAX.
83.4% of FXNAX 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 | FXNAX | |
|---|---|---|
| Top 10 holdings | 39.5% | 69.4% |
| Positions held | 168 | 1,266 |
| Cost per $10,000 held, per year | $58 | $3 |
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 FXNAX overlap?
AIVSX and FXNAX overlap 0.2% by portfolio weight — largely distinct portfolios. They share 2 holdings. The figure comes from current issuer holdings files (AIVSX as of 2026-03-31, FXNAX as of 2026-02-28).
How is the overlap between AIVSX and FXNAX 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 FXNAX 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 FXNAX?
That depends on your goals — we state facts, not advice. At 0.2% overlap, each fund still contributes meaningfully distinct exposure.
What does AIVSX own that FXNAX doesn't?
AIVSX holds 168 positions and FXNAX holds 1,266; 166 of AIVSX's positions don't appear in FXNAX at all, and they are 100.1% of AIVSX by weight.
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Related comparisons
Sources: issuer holdings files, AIVSX as of 2026-03-31, FXNAX as of 2026-02-28. Weights are fractions of each fund. Diagnostics, not advice.