Learn: closet indexing, active share, and fund fees

Explainers

• What is a closet index fund?

  A closet index fund charges active management fees for a portfolio that mostly matches its benchmark. Here is the measured definition we use, and how many funds in our registry meet it.

• What is active share, and what counts as low?

  Active share measures how much of a fund's portfolio differs from its benchmark index. Here are the thresholds we publish against and the measured spread across our registry.

• How do I check whether my fund is a closet indexer?

  Four steps using filed holdings rather than marketing material, plus an honest account of which funds our registry cannot yet classify and why.

• What does holdings overlap actually mean?

  Holdings overlap and active share answer different questions about the same two portfolios. Here is what each one does and does not tell you.

• What am I really paying for the active part of my fund?

  If most of a portfolio matches an index you could buy cheaply, the whole fee is buying only the part that differs. Here is that cost, computed per fund.