ANCFX vs FXAIX: 41% overlap
American Funds Fundamental Investors A and Fidelity 500 Index share 40.7% 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 — FXAIX 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 1.6. Two funds that shared nothing would score 2.0; two identical funds score 1.0.
Top shared holdings
ANCFX and FXAIX hold 136 of the same securities. The ten contributing most to the overlap figure:
| Holding | in ANCFX | in FXAIX | Δ |
|---|---|---|---|
| MSFT | 4.5% | 5.0% | 0.4% |
| NVDA | 3.6% | 7.3% | 3.7% |
| AMZN | 2.8% | 3.5% | 0.7% |
| AVGO | 5.9% | 2.6% | 3.4% |
| GOOG | 3.6% | 2.5% | 1.2% |
| META | 2.3% | 2.4% | 0.1% |
| GOOGL | 1.6% | 3.1% | 1.5% |
| AAPL | 1.5% | 6.6% | 5.1% |
| LLY | 1.0% | 1.4% | 0.5% |
| V | 1.2% | 0.9% | 0.3% |
Where ANCFX and FXAIX 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 | ANCFX | FXAIX | Δ |
|---|---|---|---|
| Unclassified | 9.3% | 3.3% | +6.0pp |
| Consumer Staples | 9.4% | 5.4% | +4.1pp |
| Information Technology | 27.8% | 31.8% | −3.9pp |
| Financials | 8.1% | 12.0% | −3.8pp |
| Industrials | 12.0% | 8.3% | +3.7pp |
| Health Care | 6.2% | 9.6% | −3.4pp |
| Communication Services | 9.0% | 10.5% | −1.6pp |
| Energy | 2.3% | 3.4% | −1.1pp |
Δ is ANCFX minus FXAIX, 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
33.1% of ANCFX by weight, held in no part of FXAIX.
33.6% of FXAIX by weight, held in no part of ANCFX.
A large count with a small weight is the usual shape: the positions one fund adds are typically its smallest ones.
Concentration and cost
| ANCFX | FXAIX | |
|---|---|---|
| Top 10 holdings | 34.1% | 36.4% |
| Positions held | 233 | 506 |
| Cost per $10,000 held, per year | $61 | $1 |
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 ANCFX and FXAIX overlap?
ANCFX and FXAIX overlap 40.7% by portfolio weight — moderate overlap. They share 136 holdings. The figure comes from current issuer holdings files (ANCFX as of 2026-03-31, FXAIX as of 2026-02-28).
How is the overlap between ANCFX and FXAIX calculated?
As the sum of the smaller weight in each fund, over every holding both funds own: Σ min(wA, wB). If ANCFX holds a stock at 6% and FXAIX 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 ANCFX and FXAIX?
That depends on your goals — we state facts, not advice. At 40.7% overlap, each fund still contributes meaningfully distinct exposure.
What does ANCFX own that FXAIX doesn't?
ANCFX holds 233 positions and FXAIX holds 506; 96 of ANCFX's positions don't appear in FXAIX at all, and they are 33.1% of ANCFX by weight.
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Related comparisons
Sources: issuer holdings files, ANCFX as of 2026-03-31, FXAIX as of 2026-02-28. Weights are fractions of each fund. Diagnostics, not advice.