Types of ESG Funds and Their Differences
What Are the Different Types of ESG Funds?
ESG funds are not a single category — they range from broad market portfolios with minimal fossil fuel exclusions to concentrated impact vehicles targeting specific social outcomes. The differences in strategy, portfolio construction, ESG methodology, and expected investment outcomes are large enough that two funds both labeled "ESG" may have almost nothing in common in practice. Understanding the taxonomy of ESG fund strategies is the foundation for evaluating whether a specific fund actually matches an investor's stated objectives.
ESG fund strategies describe the different approaches investment managers use to incorporate environmental, social, and governance considerations into portfolio construction — ranging from exclusionary screens through best-in-class selection, integration, thematic focus, and active impact investment.
Key Takeaways
- Exclusionary screening removes specific industries or activities (tobacco, weapons, fossil fuels) from the investment universe without necessarily improving the ESG quality of remaining holdings.
- Best-in-class selection overweights ESG leaders within each sector, allowing exposure to high-emitting industries while favoring the better-managed companies within them.
- ESG integration incorporates ESG factors into fundamental analysis without applying explicit exclusions or tilts.
- Thematic funds target specific ESG themes (clean energy, water, circular economy) with concentrated sector exposure.
- Impact funds seek measurable, intentional positive outcomes alongside financial returns, with the most demanding ESG methodology.
The ESG Fund Strategy Spectrum
ESG fund strategies sit on a spectrum from light ESG integration to deep impact investing. The Global Sustainable Investment Alliance (GSIA) categorizes sustainable investing approaches as follows:
1. Exclusionary (Negative) Screening
The oldest and most widespread ESG approach. Exclusionary screens remove companies or industries from the investment universe based on specific activities. Common exclusions:
- Tobacco production (most ESG funds)
- Cluster munitions and anti-personnel mines (virtually universal)
- Thermal coal mining above a revenue threshold
- Oil sands extraction
- Adult entertainment
- Gambling (in some Islamic finance and religious-mandate funds)
Portfolio construction implication: The remaining universe is investable; allocation within it is typically market-cap weighted or active fundamental selection.
ESG quality implication: Exclusions remove the worst ESG violators but do not actively select ESG leaders. The resulting portfolio can hold companies with mediocre ESG management as long as they are not in an excluded industry.
2. ESG Integration
ESG integration incorporates material ESG factors into investment analysis alongside financial factors, without applying explicit exclusions or tilts. The manager assesses ESG risks and opportunities as part of fundamental analysis, adjusting valuation and position sizing accordingly.
Portfolio construction implication: Portfolio resembles a fundamental active strategy; ESG quality is one factor among many in position sizing.
ESG quality implication: Depends entirely on the manager's investment process — genuine integration can produce strong ESG quality; nominal integration ("we consider ESG") may produce minimal differentiation.
3. Best-in-Class / Positive Screening
Best-in-class strategies overweight companies with above-average ESG scores within each sector. Unlike exclusionary approaches, best-in-class can hold oil companies (the ESG leaders within energy) and other high-risk sectors.
Portfolio construction implication: Sector-neutral or sector-tilted portfolio with ESG quality tilt within each sector.
ESG quality implication: Higher average ESG quality than the market; maintains diversification across sectors; includes transitioning companies that exclusionary approaches would eliminate.
4. ESG Momentum / Improvers
ESG momentum strategies favor companies with improving ESG scores or trajectories rather than those with currently high absolute scores. The theory: companies that are rapidly improving ESG quality are ahead of market pricing of that improvement.
Portfolio construction implication: Selects companies with measurable ESG score improvement over a defined period.
5. Thematic ESG Investing
Thematic strategies concentrate exposure in specific ESG-related themes:
- Clean energy (solar, wind, storage, grid)
- Water and utilities
- Circular economy and waste management
- Sustainable food and agriculture
- Smart cities and mobility
Portfolio construction implication: High sector concentration; significant deviation from broad market weights; often small/mid cap heavy.
ESG quality implication: High thematic relevance; may include companies with mixed overall ESG quality that contribute to the theme.
6. Shareholder Engagement and Active Ownership
Some funds focus their ESG strategy primarily on active engagement with portfolio companies — using ownership rights to advocate for governance, climate, and social improvements. The portfolio may resemble a broad market fund; the ESG value-add is created through engagement outcomes rather than portfolio composition.
7. Impact Investing
Impact investing seeks measurable, intentional positive outcomes alongside financial returns. Characteristics:
- Intentionality: Explicitly designed to produce defined social or environmental outcomes
- Additionality: Capital is directed where it has additional impact, not merely where good activities already happen
- Measurability: Outcomes are quantified against defined indicators
- Financial return: Returns range from below-market ("concessional") to market-rate, depending on strategy
Impact investing is most developed in private markets (social impact bonds, development finance, green project finance) but has expanded into public equities through "impact-tilted" equity strategies.
SFDR Classification as a Fund Taxonomy
Under the EU's Sustainable Finance Disclosure Regulation, EU-registered funds are classified as:
Article 6: No ESG integration claim — conventional funds that disclose how they do not consider sustainability risks.
Article 8: "Light green" — funds that "promote" environmental or social characteristics. The most common ESG fund classification; includes funds with exclusion screens, ESG integration, and best-in-class strategies.
Article 9: "Dark green" — funds that have sustainable investment as their objective. Typically thematic, impact, and SRI funds with explicit sustainability outcomes targets. Expected to have some form of Principal Adverse Impact (PAI) consideration.
The SFDR taxonomy is imperfect but provides a regulatory reference point for comparing ESG ambition levels across EU-registered funds.
Comparing Strategies on Key Dimensions
Common Mistakes
Assuming "ESG fund" means high ESG quality. Article 8 funds range from meaningful ESG integration to funds with minimal ESG differentiation from standard indices. The SFDR category is a floor, not a quality standard.
Selecting thematic funds without understanding concentration risk. Clean energy funds investing heavily in solar panel manufacturers in 2020–2021 experienced significant drawdowns in 2022–2023 as interest rates rose and policy uncertainty increased. Thematic concentration creates significant volatility relative to broad ESG funds.
Treating engagement-focused funds as passive. Funds with significant engagement programs may hold companies that look unfavorable on a point-in-time ESG screen but are active ownership targets. ESG quality must be assessed in the context of the engagement strategy.
Frequently Asked Questions
Which ESG fund type is best? There is no universally "best" type — the right strategy depends on the investor's objective. For values-driven exclusion, exclusionary funds are most appropriate. For broad market ESG quality, best-in-class is often preferred. For specific environmental themes, thematic funds. For measurable social outcomes, impact vehicles. Most sophisticated ESG investors combine multiple approaches across their portfolios.
What is the difference between SRI and ESG? Socially Responsible Investing (SRI) is historically associated with values-based exclusions — removing "sin stocks" from portfolios. ESG investing has evolved to encompass a broader range of approaches, including risk integration that does not necessarily involve exclusions. The distinction is blurring: modern SRI funds use ESG data, and many ESG funds include ethical exclusions.
Related Concepts
Summary
ESG fund strategies range from simple exclusion screens through best-in-class selection, integration, thematic concentration, and full impact investing. Each approach constructs portfolios differently, produces different ESG quality profiles, and carries different investment risk characteristics. SFDR's Article 6/8/9 classification provides a regulatory reference framework but should not be confused with a quality ranking. Effective fund evaluation requires understanding which ESG strategy type is being used, how the methodology is implemented, what ESG quality the resulting portfolio achieves, and whether the approach genuinely matches the investor's objectives.