ETF Share Classes: The Twenty Five Year Exception Just Became the Rule

For a quarter of a century, one firm could do something no competitor could. Vanguard ran mutual funds that had an ETF share class attached, so the same portfolio, the same manager and the same holdings could be bought either way. Everybody else had to choose.

That is over. Applications had been stacking up since the patent expired, the SEC granted the first new relief in November 2025, the exchanges adopted listing standards that same month, and the broker-dealer relief landed in March 2026. The structure is now available to the industry rather than to one firm.

For an adviser this is worth understanding for a specific reason. It changes what you are looking at when you compare two tickers, and it makes a question that used to be simple, is this a mutual fund or an ETF, into a question with a third answer.

What the structure actually is

Start with what a share class is, because the ETF version is not a new invention so much as an old idea extended.

A mutual fund already issues multiple share classes. Institutional, investor, retirement, and historically A, B and C shares with different loads. They are claims on one pool of securities, differing only in fee structure and who can buy them. One portfolio, one manager, several doors into it.

An ETF share class is another door. The fund holds one portfolio. Some investors buy a mutual fund class and transact at the end of the day at net asset value, directly with the fund. Others buy the ETF class and trade it on an exchange all day, with creation and redemption handled by authorized participants.

The holdings are identical because there is only one set of holdings. The performance before fees is identical. What differs is how you get in and out, and what that route costs.

The industry saw this coming well before it arrived. Brett Eichenberger of Cohen & Company, who audits registered funds, flagged it as pending and noted it runs both directions: "The other thing we could potentially see on the horizon is an ETF share class of mutual funds," and equally "we’re also seeing it on the other side where you have an ETF like yours that could then potentially offer a mutual fund share class."

He also placed the history correctly: "obviously, Vanguard’s had that for many, many years now, over 20 years, where we’ve seen a lot of exemptive reliefs filed for this."

How it opened up

The short version. Vanguard obtained exemptive relief in 2000 and held a patent on the structure that kept everyone else out. The patent expired in 2023, and applications began arriving.

The SEC issued a notice of intent on Dimensional Fund Advisors’ application on 29 September 2025 and granted the order on 17 November 2025, making Dimensional the first firm since Vanguard to receive it. By 17 March 2026 the Commission recorded approximately a hundred applications filed, roughly half of which had already been granted. Most of those had been pending well before Dimensional’s order rather than filed in response to it. The exchanges adopted generic listing standards for the structure on 24 November 2025, all three on the same day. The broker-dealer relief followed on 17 March 2026, when the Commission granted conditional exemptions from Rules 10b-10 and 14e-5 and from Section 11(d)(1).

Garrett Stevens and Rich Malinowski of Exchange Traded Concepts described the wave from inside the industry while it was still pending: "you’ve got all of the recent share class applications with the SEC to copy the" "Vanguard model and offer either an ETF share class of a mutual fund or a mutual fund share" class of an ETF.

Why issuers wanted it so badly

The commercial logic is worth spelling out, because it explains the hundred applications better than any investor benefit does.

Jeff Cullen of Schafer Cullen Capital Management put it in the plainest terms available: adding an ETF share class to an existing mutual fund is more workable "because if you make an individual share ETF from scratch, you start from zero." As a share class it does not start from zero, because the fund already has assets.

That is the whole thing. Launching a standalone ETF means starting at zero assets, funding years of costs, and hoping distribution arrives. Adding a share class to a fund that already has three billion dollars in it means the ETF is born with a track record, an existing portfolio and scale on day one.

Matt Camuso of Baron Capital described the pent-up demand from the traditional side, calling "ETF as a share class, probably being the biggest one" of the things that had been sitting on the sidelines, and reading the speed of adoption as "signs of just that pent up demand to access this" market.

What it means for an investor

The strategy question and the wrapper question separate. You can now evaluate a manager on the merits and choose the delivery mechanism afterward. Those used to be one decision.

Tax efficiency is the real open question. The ETF’s in-kind creation and redemption machinery is what makes an ETF tax efficient, and in this structure it operates inside a fund that also faces cash redemptions from its mutual fund holders. Those cash redemptions force sales, sales realise gains, and gains are distributed across the whole fund. In principle the in-kind flows can flush embedded gain out and offset that. In practice the benefit depends on the balance of flows between the two classes, and it is genuinely fund-specific.

This is the part to watch rather than assume. If you are buying the ETF class of a large legacy mutual fund for the tax treatment, the honest answer today is that the structure permits it and the history to prove it out does not yet exist.

Embedded gains come with the building. An ETF share class attached to a twenty year old mutual fund is a share class of that fund, including its accumulated unrealised gain. A newly launched standalone ETF starts clean.

Fees may differ, and the operational costs do. The classes have their own expense structures. The ETF class avoids some shareholder servicing costs and picks up listing and market-making ones.

What to actually check

Is this ticker a standalone ETF or a share class of something? The prospectus says so, and it is the first thing to establish, because everything else follows from it.

If it is a share class, how big is the mutual fund side and which way is it flowing? Large, stable mutual fund assets alongside a growing ETF class is a benign picture. Large mutual fund assets in sustained redemption is the case where cash-raising sales could generate gains for everyone in the fund.

What is the fund’s distribution history? Not the ETF class’s history, which will be short. The fund’s.

What are the accumulated unrealised gains? Disclosed in the annual report, and directly relevant if you are buying into a long-lived portfolio.

The framing worth keeping

An ETF used to be a fund structure. In this arrangement it is a distribution channel, and the fund underneath it may be decades old with a history of its own.

That is not a criticism of the structure. It solves a genuine problem for managers with good strategies stuck in a wrapper investors have stopped buying, and it gives investors access to portfolios that were previously behind a minimum and an end-of-day trade. It does mean the ticker tells you less than it used to, and the prospectus tells you more.

This is educational content and not investment advice. It is not a recommendation regarding any security. Investing involves risk, including possible loss of principal. Past performance does not guarantee future results.