Learn · Holdings filed for periods June 30, 2026 to August 31, 2026
What is active share, and what counts as low?
Data as of June 30, 2026 to August 31, 2026 holdings (filed July 20, 2026 to October 29, 2026)
Active share is the share of a fund’s portfolio that differs from its benchmark index, measured position by position. A fund at 30% active share has 70% of its portfolio in the same holdings at the same weights as the index, so only 30% of it can possibly perform differently.
Across 200 funds with measured active share in our registry as of August 31, 2026, 16 sit under 5%, 99 fall in the 5% to 60% closet-index range, and 85 reach 60% or more.
The thresholds we publish against
| Band | What it means | Funds |
|---|---|---|
| Under 5% | Index tracking. The fund is not trying to differ from the index. | 16 |
| 5% to 60% | The closet-index range. Most of the portfolio matches the index. | 99 |
| 60% and over | Genuinely active. The portfolio substantially differs. | 85 |
The 60% line is the convention in the academic literature that introduced the measure, and we publish against it rather than inventing our own. The 5% floor is ours: it separates funds that match an index because that is their stated job from funds that match one while charging to differ.
The measured range
The lowest active share in the registry is Vanguard Total Stock Market Index Fund (VITSX) at 0.0002% — an index fund holding its index. The highest is The Fairholme Fund (FAIRX) at 97.4%, a portfolio with almost nothing in common with its best-fit comparison.
0 published funds have no measured active share at all. That is a gap in the holdings data, not a score of zero.
How the number is produced
Active share compares a fund’s holdings with the index’s, position by position, and adds up the portion that does not match. Half the sum of the absolute weight differences gives a figure between zero and one hundred per cent: zero when the two portfolios are identical, one hundred when they share nothing.
Two practical things follow. Holdings must be matched to the same security before they can be compared, which depends on the identifiers both filings disclose; where too little matches, we publish no figure rather than one computed on the fraction that did. And the result moves with the benchmark chosen, so a fund can sit above the line against one index and below it against another.
Why the thresholds are where they are
The 60% line is the convention in the academic literature that introduced the measure, and we publish against it rather than inventing our own. Below it, a majority of the portfolio is doing what the index does. The 5% floor is ours, and it exists to separate two populations that would otherwise be scored together: funds that match an index because tracking it is their stated job, and funds that match one while charging to differ.
Neither line is magic. A fund at 58% and a fund at 62% are not different in kind, and we would rather publish the number than argue about the band it falls in. The bands exist to make a large registry readable, not to settle individual cases.
What a low number does not tell you
Active share says nothing about returns. A high-active-share fund can lose to its index for a decade, and a fund at 30% can beat it. What a low number does establish is arithmetic: the part of the portfolio that matches the index will return what the index returns, minus the fee charged on it.
It is also benchmark-dependent. Active share is measured against a specific index; against a different one the same portfolio scores differently. We publish the best-fit comparison we computed, and name it on every fund page.
And it is blind to anything that is not an equity holding. A fund whose strategy lives in options, futures or cash management can show a low active share while doing something quite unlike its index. The measure sees portfolios, not intentions, which is its strength when reading a fee and its limit when reading a strategy.
Reading it alongside the fee
On its own, active share is a description, not a verdict. It becomes useful the moment it is set against what the fund charges, because the two together answer a question neither answers alone: how much portfolio difference is this fee buying? A fund at 20% active share charging a tenth of a per cent is a cheap near-tracker. The same 20% at one and a half per cent is a very different proposition, and the number by itself cannot tell them apart.
That pairing is what the registry publishes for every fund it can classify, and it is why a fund is never labelled on active share alone.
Next: what the active part actually costs, or read the full methodology.