Main Thematic Innovation ETF (TMAT)
TMAT — the Main Thematic Innovation ETF — invests in publicly traded companies identified as leaders or beneficiaries of major structural themes shaping global markets. The portfolio is rebalanced regularly to stay ahead of changing innovation fronts, from artificial intelligence and robotics to biotechnology and renewable energy.
The thematic investing movement and Main’s entry
Thematic investing emerged in the early 2010s as a distinct strategy: rather than buying broad sectors or markets, investors could construct a portfolio around a single transformative idea — think cloud computing, cybersecurity, or autonomous vehicles. The premise is that structural shifts (technological, demographic, regulatory, environmental) create winners and losers, and forward-looking investors can capture returns by identifying the winners early.
Main Street Partners (the asset manager behind TMAT) launched the Thematic Innovation strategy to capitalize on this opportunity. The idea was not novel, but the execution aimed to be rigorous: rather than assembling a static list of “innovation stocks,” the fund would identify evolving themes, refresh holdings quarterly, and stay positioned at the frontier of change. This requires active management and thematic research.
How the portfolio is constructed
TMAT begins with a universe of global equities (primarily US-listed companies, but with some international holdings). The investment team identifies thematic trends they believe will drive returns over the next three to five years. These are not short-term trades but medium-term structural shifts.
Recent themes have included artificial intelligence and machine learning, genomics and precision medicine, renewable energy and energy storage, automation and robotics, financial technology, and digital transformation. The team then selects companies they believe are positioned to benefit from these trends. This might include core infrastructure providers (makers of AI chips, renewable energy systems), early-stage innovators (biotech companies, software platforms), and established companies that are pivoting into new directions (legacy manufacturers adding robotic capabilities).
The portfolio is typically held in 20–50 positions, smaller than a traditional equity fund, which means meaningful allocation to thematic conviction. It is rebalanced quarterly, which allows the team to shift capital as themes evolve. If artificial intelligence moves from emerging to mature, for instance, the fund might rotate out of pure AI-play companies and into established tech firms using AI to improve operations.
The investor appetite for thematic funds
The appeal is straightforward: global demographic and technological change is real and long-term. Someone who believes the future is shaped by aging populations, climate transition, automation, and life-sciences innovation might reasonably want a portfolio tilted toward those trends. Thematic funds offer a packaged way to gain that exposure without having to identify individual winners and losers.
The risk is equally clear: thematic trends are not certainties. Artificial intelligence might drive extraordinary returns, or it might become commoditized and fail to produce outsized profits. Renewable energy is structurally sound but is cyclically driven by policy and commodity prices. A thematic fund’s success depends on both the thesis (Is the trend real? Will it last?) and the stock-picking (Has the team identified the right beneficiaries?).
How TMAT has evolved
Since inception, TMAT has lived through multiple market cycles and theme rotations. In the post-2020 period, the fund benefited from the sharp tech rally and the early enthusiasm for automation and AI. During the 2022 rate-hiking cycle, thematic funds suffered alongside growth stocks because many themes are embodied in high-growth companies with stretched valuations. The rebound in tech and AI in 2023–2024 has again favoured thematic positioning.
The quarterly rebalancing has allowed the fund to pivot. In periods when particular themes cooled, the team could reduce exposure and reallocate to emerging trends. This active management is the fund’s intended edge, though it also introduces the risk of poor timing and theme selection.
The fees and cost of active management
TMAT carries an expense ratio typical of actively managed equity funds — higher than a broad-market index ETF but in line with other thematic managers. The cost reflects the research required to identify themes, track companies, and execute quarterly rebalancing. Unlike passive index funds, which simply hold a fixed basket, TMAT’s value proposition depends on the quality of the active decisions.
Investors pay this fee because they believe the thematic approach — being positioned ahead of structural changes — will produce returns that exceed the benchmark and cover the cost. This is always an open question. Over long periods, active managers on average underperform broad indices net of fees. But thematic managers might be an exception if they genuinely identify trend winners before the broader market catches on.
Risks in thematic concentration
Thematic funds are inherently concentrated. TMAT is not diversified across all sectors of the economy — it is overweighted toward technology, healthcare, and industrials (automation) and underweighted toward traditional sectors like energy, finance, and consumer staples. This concentration is intentional and is the source of potential outperformance, but it is also a source of volatility.
If the markets decide that legacy sectors (value, dividend payers) are due for a rotation, TMAT would suffer. If the broad market experiences a drawdown and investors flee high-growth, innovative stocks (as happened in 2022), TMAT would likely decline faster than the overall market. The fund is not a defensive holding.
The other risk is theme momentum. Thematic funds can drive herding: as money flows into AI or renewable energy thematic funds, prices for those stocks rise, making them attractive to the thematic managers, which drives more money in, creating a feedback loop. When sentiment shifts and the flows reverse, the unwinding can be sharp.
The quarterly rebalancing question
The fund’s quarterly refresh is meant to keep it agile and forward-looking. But it introduces costs — trading costs, tax consequences (though the fund is structured to minimize this), and the risk of poor timing. If the team sells a theme too early, they miss the subsequent rally. If they hold too long, they overstay a trend.
Mechanically, quarterly rebalancing means the fund is always in a state of transition. Holdings are changing regularly, which affects how the fund behaves. Over a quarter, the team is evaluating which themes are wearing out and which are emerging. This is dynamic, but it also means there is no static “TMAT portfolio” — the portfolio is always becoming something else.
Comparison to broader growth and technology funds
Investors considering TMAT might compare it to:
- A broad growth ETF (captures much of the same upside but with lower fees and less active risk)
- A technology-sector ETF (similarly growth-oriented but sector-specific, not theme-specific)
- A dividend or value ETF (very different positioning, less thematic, more defensive)
- An actively managed growth fund (similar fees and active management, possibly different stock-picking discipline)
The differentiation is the thematic lens. If the investor believes that thematic trends are the primary drivers of future returns and that TMAT’s team can identify them effectively, then the fund is worth the fees. If the investor is skeptical of active management or believes broad diversification is superior to thematic concentration, a passive growth index fund might be more appropriate.
How to evaluate TMAT over time
Start with the fund’s fact sheet, which lists the major themes and the top holdings. Google a few of those holdings to understand what TMAT owns and why. The most recent quarterly fact sheet will show the latest rebalancing and any major shifts in the portfolio.
Compare TMAT’s total return (including dividends) to a broad growth benchmark (such as the Nasdaq-100 or the Russell 1000 Growth Index) over multiple time periods: one year, three years, five years. Track whether TMAT is adding or subtracting value. In periods where the thematic trends are in favour, TMAT should outperform. In periods where growth stocks are out of favour or valuation is collapsing, TMAT will likely underperform.
Ask yourself: Do I have conviction that these particular themes will drive market returns? Do I trust this management team to identify winners within those themes? Am I comfortable with the volatility? If yes on all counts, TMAT might fit. If you’re uncertain on any, the fees are hard to justify. A passive fund offers a lower-cost way to own growth stocks without betting on the manager’s thematic insights.