RGAGX vs SPY: 50% overlap
American Funds Growth Fund of America R6 and SPDR S&P 500 ETF Trust share 49.6% of their portfolios by weight — computed as Σ min(wA, wB) over every holding both funds own.
Different holding dates. These holdings were published about 5 months apart — RGAGX as of 2026-02-28, the rest through 2026-07-23. 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 1.5. Two funds that shared nothing would score 2.0; two identical funds score 1.0.
Top shared holdings
RGAGX and SPY hold 170 of the same securities. The ten contributing most to the overlap figure:
| Holding | in RGAGX | in SPY | Δ |
|---|---|---|---|
| NVDA | 6.1% | 7.9% | 1.9% |
| MSFT | 4.0% | 4.4% | 0.4% |
| GOOGL | 2.9% | 2.9% | 0.0% |
| AVGO | 4.3% | 2.9% | 1.4% |
| AMZN | 2.9% | 3.6% | 0.7% |
| GOOG | 2.9% | 2.4% | 0.6% |
| META | 4.2% | 2.1% | 2.2% |
| AAPL | 1.8% | 7.4% | 5.6% |
| MU | 1.8% | 1.8% | 0.0% |
| LLY | 3.3% | 1.5% | 1.9% |
Where RGAGX and SPY 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 | RGAGX | SPY | Δ |
|---|---|---|---|
| Unclassified | 7.6% | 0.0% | +7.6pp |
| Information Technology | 30.6% | 37.5% | −6.9pp |
| Financials | 6.5% | 12.4% | −5.8pp |
| Communication Services | 13.2% | 9.3% | +3.9pp |
| Consumer Discretionary | 12.7% | 8.8% | +3.9pp |
| Consumer Staples | 2.4% | 4.6% | −2.2pp |
| Health Care | 11.0% | 9.1% | +1.8pp |
| Utilities | 0.5% | 2.3% | −1.8pp |
Δ is RGAGX minus SPY, 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
24.1% of RGAGX by weight, held in no part of SPY.
24.8% of SPY by weight, held in no part of RGAGX.
A large count with a small weight is the usual shape: the positions one fund adds are typically its smallest ones.
Concentration and cost
| RGAGX | SPY | |
|---|---|---|
| Top 10 holdings | 36.7% | 36.9% |
| Positions held | 309 | 505 |
| Cost per $10,000 held, per year | $30 | $9 |
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 RGAGX and SPY overlap?
RGAGX and SPY overlap 49.6% by portfolio weight — moderate overlap. They share 170 holdings. The figure comes from current issuer holdings files (RGAGX as of 2026-02-28, SPY as of 2026-07-23).
How is the overlap between RGAGX and SPY calculated?
As the sum of the smaller weight in each fund, over every holding both funds own: Σ min(wA, wB). If RGAGX holds a stock at 6% and SPY 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 RGAGX and SPY?
That depends on your goals — we state facts, not advice. At 49.6% overlap, each fund still contributes meaningfully distinct exposure.
What does RGAGX own that SPY doesn't?
RGAGX holds 309 positions and SPY holds 505; 138 of RGAGX's positions don't appear in SPY at all, and they are 24.1% of RGAGX by weight.
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Related comparisons
Sources: issuer holdings files, RGAGX as of 2026-02-28, SPY as of 2026-07-23. Weights are fractions of each fund. Diagnostics, not advice.