Harbor Osmosis International Resource Efficient ETF (EFFI)

The appeal of owning the whole world and owning only the world’s most efficient companies is simple: you do not give up growth to embrace sustainability.

The Harbor Osmosis International Resource Efficient ETF takes the resource-efficiency screen global. While Harbor’s emerging-markets fund (EFFE) targets only developing economies, EFFI casts wider — it holds companies from both developed and emerging markets that have demonstrated efficient use of resources. The fund owns utilities in Germany, tech manufacturers in South Korea, miners in Australia, and financial firms in Singapore, selected on a single criterion: do more with less.

The index underlying EFFI applies resource-efficiency metrics to a broad international equity universe spanning nearly all countries and sectors. Unlike a simple global index that weights companies by market capitalization regardless of efficiency, EFFI’s index screens for environmental resource use — carbon intensity, water consumption, material waste, circular economy practices — and constructs a portfolio that overweights efficient producers while underweighting inefficient ones. A company can be in any industry, any geography; the screen is blind to sector and region.

Issued by Harbor Capital Advisors as a standard exchange-traded fund, EFFI holds actual company shares, trades with intraday pricing and liquidity, and carries an expense ratio in the range of global equity ETFs. It has no leverage, no derivative overlays, no daily reset mechanics — it is straightforward equity investing with a sustainability lens applied at the portfolio level.

The strategy rests on two observations. First, resource efficiency often signals better management. A company that has invested in lean manufacturing, renewable energy, waste reduction, and circular supply chains tends to have capital discipline, lower operating costs, and higher margins. Those characteristics predict returns. Second, the world is moving toward carbon pricing, resource scarcity, and regulatory pressure on waste and emissions. Companies that are already efficient face lower transition risk than those that will be forced to retool later. By overweighting efficiency today, EFFI may be front-running a shift in competitive advantage that plays out over decades.

But global diversification brings complexity. EFFI holds hundreds of securities across developed and emerging markets, each with its own currency, regulatory environment, and economic cycle. A portfolio spread so widely is by definition moderate in its bets — it cannot concentrate heavily in any single market or industry and still be called global. This breadth is protective but also dilutive: exceptional growth opportunities might be missed, and in periods when the stock market is driven by narrow momentum in a few mega-cap tech names, a broad diversified fund underperforms simply by not being concentrated enough.

Currency exposure across EFFI is real. Holdings include companies priced in dollars, euros, yen, yuan, rupees, and dozens of other currencies. A strengthening dollar erodes returns; a weakening dollar enhances them. Over years this averaging cancels somewhat, but over shorter periods it is a major source of volatility independent of stock performance.

The efficiency screen itself is backward-looking and imperfect. Companies are ranked on past and current resource use; this does not guarantee future efficiency or that their investments in sustainability will pay off. And the screening data varies in quality across regions: transparency and standardization are higher in developed markets, lower in emerging ones, creating potential bias in what gets captured.

Researching EFFI requires starting with the prospectus, which lays out exactly which efficiency metrics are used and how holdings are selected. The fact sheet shows the current portfolio — the top holdings, geographic and sector breakdowns, and an honest look at where the fund is concentrated. Comparing EFFI’s returns, volatility, and sector makeup to a simple global market-cap index (such as MSCI All Country World Index) over multiple periods reveals whether the efficiency filter has driven outperformance or merely shifted volatility around. Looking at the fund’s performance across market regimes — years of tech dominance, years of value dominance, crisis years — shows how the sustainability screen behaves when markets shift.