AllianzIM U.S. Equity Buffer15 Uncapped May ETF (MAYU)

The AllianzIM U.S. Equity Buffer15 Uncapped May ETF (MAYU) wraps the US equity market inside a structure that provides 15% annual downside protection while allowing investors to capture gains dollar-for-dollar with no ceiling — a rare combination that appeals to investors who want a cushion against crashes but will not accept truncated upside.

“No cap on the upside. Just a floor on the downside.”

That simple framing captures MAYU’s core premise. In a market year with a −20% return, MAYU investors lose 5% (the 15% buffer absorbs the first 15 percentage points). In a year with a +25% return, MAYU investors capture the full 25%. The cost of that uncapped upside — unusual in the buffer-fund category — is reflected in the 15% downside protection, which is higher than some competing funds, and in the fund’s expense ratio.

The uncommon trade: bigger buffer, no cap

Buffer-fund managers typically offer downside protection by capping upside. The fee paid by option sellers (who write the downside protection) reduces what can be offered to upside investors. MAYU inverts that constraint: it offers a deep buffer — 15%, deeper than most peers — and uncapped upside. The result is a more expensive fund, because the managers must source the downside protection from somewhere other than sold upside.

The strategy likely involves long put options on the US equity index, funded in part by selling shorter-dated options or managing a collar with a very high strike (one that is far above current prices and hence inexpensive to sell). The net cost is higher than a fund that caps upside, which is why MAYU’s expense ratio is above the typical 0.35% range — expect something closer to 0.50% to 0.75% annually.

The “uncapped” feature means MAYU does not reset its upside limit each May the way other buffer funds do. Instead, the fund resets the buffer level (maintaining the 15% protection) but allows all gains, no matter how large, to flow through to shareholders. This is mechanically complex: the fund must continuously adjust its hedge as prices move higher, buying more protection when the buffer is partially consumed and scaling back when the index rallies.

The equity universe and mechanics

MAYU provides exposure to the broad US equity market — large caps, mid-caps, and small caps. The fund does not hold all stocks; it typically holds a representative sample of 300+ companies and uses equity index derivatives to synthesize the remainder and to embed the buffer and cap mechanics.

The annual reset in May recalibrates the 15% downside barrier. The buffer is fixed by design; what changes from year to year is the cost of maintaining it, which flows through to the expense ratio. A year with elevated volatility means costlier hedging, which may raise the fund’s fees slightly or reduce assets from slightly weaker returns. A calm year does the opposite.

Costs and the price of uncapped upside

MAYU’s expense ratio is higher than peers, likely 0.55% to 0.70% per year. This reflects the cost of the deep downside protection (15% is a thick buffer) plus the cost of eliminating the upside cap. For investors paying an extra 0.30% to 0.40% per year versus a capped buffer fund, the benefit is real only if they hold through at least one or two strong rally years where they would have been capped by the alternative.

The fund is liquid, trading on the NASDAQ throughout the day, but the complexity of the derivative structure means trading volume may be lower than plain-vanilla index funds. Bid–ask spreads are usually tight for investors in round lots (100 shares or more), but the liquidity is dependent on market conditions and the fund’s assets under management.

The reality of the 15% buffer

The 15% downside protection is an annual feature. An investor who experiences a year with a −25% market return loses 10% (the 15% buffer mitigates 15 percentage points). An investor who experiences three years of −10%, −5%, and −5% market returns loses 5%, 0%, and 0% in MAYU — the buffer absorbs the full decline each year.

But the buffer does not carry over across years. If the market falls 10% in year 1, the investor loses 0% in MAYU. If the market then falls another 10% in year 2, the investor again loses 0% in MAYU (because a fresh 15% buffer applies). However, if the market falls 15% in year 1, the investor loses 0%; if it falls another 15% in year 2, the investor loses 0% in year 2. The buffer resets annually, not cumulatively.

An investor who buys and holds MAYU for a decade experiences 10 separate one-year buffers. Those periods when the market fell more than 15% benefited fully from the protection; those when it fell less saw partial protection; and those when it rose benefited from the uncapped upside.

Who MAYU suits

MAYU is designed for:

Investors who have lived through sharp downturns and want real downside insurance without sacrificing upside when optimism returns.
Conservative allocators who want a “growth equity” position with a meaningful floor, especially in late career or early retirement when portfolio damage feels costly.
Individuals and institutions that can tolerate the higher fees for the psychological benefit of the large buffer and the full upside capture.
Portfolios where MAYU serves as a complete “equity with guardrails” allocation, reducing the need for external hedging or a separate bond position.

MAYU is less suitable for:

Investors who are cost-sensitive and would feel the 0.60% fee drag over decades.
Investors who are indifferent to volatility and can stomach 30% or 40% drawdowns; the buffer provides little value to them.
Young savers with 40+ years to retirement, for whom the upside cap of capped-buffer funds is not a genuine loss over time.

How to research MAYU

Start with AllianzIM’s fund prospectus and fact sheet. Verify the exact buffer level (it should be 15%), the current expense ratio, the underlying equity universe (is it the Russell 3000? S&P 500 + midcaps?), and the reset schedule.

Examine the fund’s performance history over the past three to five May reset cycles, paying attention to down years. In a year when the broad US equity market fell 20%, did MAYU deliver approximately a 5% loss? Check for consistency. Also examine up years: in a year when equities rose 25%, did MAYU capture the full 25%? The uncapped feature should show up clearly in performance records.

Compare MAYU’s longer-term total returns (especially over a full market cycle, including at least one significant downturn) against plain-vanilla US equity index funds. The math should show whether the buffer’s protection in down years outweighs the fee burden in calmer periods. Because MAYU is more expensive than a simple index fund, it must prove its value through real downside protection, not just theory.

Finally, understand the fund’s role in a broader portfolio. MAYU is not a silver bullet; it is one tool for managing equity volatility. Investors should be clear on whether it is their sole equity holding or part of a diversified allocation.