An exchange-traded fund has seen strong performance but little adoption this year is giving itself a makeover, and is turning to cannabis to do it.

The Tierra XP Latin America Real Estate ETF US:LARE, which, as the name implies, tracks companies involved in Latin America’s real-estate market, is filing to change the focus of its holdings. The new focus amounts to a massive overhaul in exposure, strategy, region, and sector: it will now track an index of cannabis companies.

According to an October filing with the Securities and Exchange Commission, the fund, which has traded since 2015, hasn’t only decided to change its name, but in an unusual step, also “its underlying index and investment objective.”

The new fund, the Alternative Agroscience ETF, is expected to begin trading at some point in December. At that point, it will offer exposure to companies that “are primarily engaged in the legal cultivation of cannabis, or the legal production and distribution of cannabis-related products for medical or non-medical purposes,” the filing read. However, the fund “will not include any company that engages in the cultivation, production or distribution of marijuana or products derived from marijuana for medical or non-medical purposes” until it becomes legal under all local and national laws.

It isn’t unheard of for a fund to change the benchmark it tracks, but typically such changes are from one index provider to another, with little change in the underlying strategy. In 2012, for example, Vanguard adopted the FTSE Emerging Index for its emerging-market funds, replacing the MSCI Emerging Markets Index. While the two indexes differ in some notable ways, the basic exposure offered is consistent across the two.

A shift like the Tierra fund is gunning to do, where investment thesis changes, is nigh on unprecedented, said Todd Rosenbluth, director of ETF and mutual fund research at CFRA. “Unless investors read SEC filings, they’ll wake up one morning and realize they own a completely different product than what they thought.”

In a statement provided to MarketWatch, Sam Masucci, chief executive officer of ETF Managers Group, wrote, “According to rules of the 40’ ACT and SEC regulations there are clear procedures to protect and inform investors of an index change. As stated by regulation a new prospectus will be mailed out to the home of every shareholder prior to the index changeover.”

ETF Managers Group is the sponsor to the fund.

CFRA’s Rosenbluth said that the only ETF shift of this magnitude that he could think of was when Deutsche Bank last month changed one fund, which had offered currency-hedged exposure to Italy’s equity market, to an unhedged one tracking German equities US:GRMY.

“That was significant because you went from one single-country exposure to another, but this is even more surprising,” he said, suggesting the change was done because it was more efficient and inexpensive to change the focus of an existing ETF than launch a new one. “There’s an existing framework, the time to market would be faster, and they may be able to avoid the licensing and exchange fees involved with a new fund, which are expenses that can really add up.”

The filing didn’t give a ticker symbol or a fee for the new fund. The Tierra fund currently has an expense ratio of 0.79%.

The fund is extremely small and thinly traded. It has about $6 million in assets, according to FactSet, and the 30-day average trading volume is about 1,300 shares. However, the performance has been strong: up more than 24% thus far this year.

Rosenbluth hypothesized the fund’s historical performance would remain intact after the switch in the index it follows, rather than it being retroactively adjusted to match the new index’s moves. “Even though investors shouldn’t use a performance record to make their investment decisions, we know they do, and someone looking at this next year will think the 24% gain reflects marijuana, not Latin American real estate. That’s a problem, because the drivers of an emerging-market real-estate fund are night and day from marijuana investments. This fund is a wolf in sheep’s clothing.”

As for the benefits of using the existing ETF shell to create a cannabis fund rather than launching a new fund, he speculated: “There’s an existing framework, the time to market would be faster, and they may be able to avoid the licensing and exchange fees involved with a new fund, which are expenses that can really add up.”

A statement from Masucci, provided in response to an earlier version of this story, didn’t address the performance issue. However, it indicated that “being an advisor and ETF issuer we have a need to make sure a fund resonates strongly with investors and that it’s solving a portfolio allocation problem. LARE was a strategic product that was a first to market and saw strong performance, but for whatever reason the performance wasn’t reflected by the growth in investor interest.” LARE is the Tierra fund’s ticker symbol.

The change in the fund comes at a time when the ETF industry is seeing massive growth, although that growth is hugely concentrated within extremely low-fee products that provide exposure to broad swaths of various asset classes. According to Vanguard, which cited May data from Morningstar, there is nearly $8 trillion in funds that charge between 1 and 47 basis points. The next cheapest category—charging between 0.48% and 0.65% of assets—has about $2.5 trillion, a downward slope that continues the more expensive the fund is.

Funds that charge more, or which offer exposure to more niche parts of the market, have struggled to amass much in assets. Such funds can be unprofitable to run, even if they have strong performance; as a result, the number of funds that have closed has risen lately.

What every cannabis investor should be paranoid about

The new focus of the fund, if approved, will grant ETF Managers Trust access to a part of the ETF space that has proved popular and has few major players. The first marijuana-themed ETF, the Horizons Marijuana Life Sciences Index ETF HMMJ, +2.15% , made its debut earlier this year on the Toronto stock exchange.

The fund has proved popular ever since, amassing $157 million in assets, a high amount for a new fund, while its 30-day average trading volume is nearly 200,000, also on the high end for a new fund. Over the past three months, it has gained more than 30% in value.

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