This passive ETF tracks the MSCI Climate Paris Aligned Index, building a portfolio of US large- and mid-cap stocks that follows a carbon reduction trajectory consistent with the Paris Agreement's 1.5°C goal. It goes beyond a simple ESG screen by applying a weighting method based on climate scenarios.

It suits long-term investors who want US equity exposure aligned with a carbon reduction pathway while preferring a low cost burden.

It is a passively managed (index-tracking) ETF launched by BlackRock (iShares) in 2021.

The fund tracks an MSCI climate index designed to match the Paris Agreement's 1.5°C carbon reduction scenario. It adjusts the portfolio by reducing the weight of high-carbon industries and increasing the weight of companies that stand to benefit from the climate transition, following a path that gradually lowers carbon intensity relative to its parent MSCI USA Index.

• Applies a Paris Agreement carbon reduction pathway alignment approach rather than a simple ESG screen
• Its low expense ratio makes it relatively cost-efficient among climate-themed ETFs

Assets under management (AUM) stand at $2.5B, and the expense ratio is 0.10% per year.

Compared with general ESG ETFs such as ESGU, DSI, and SUSA shown in the table, PABU stands out by applying a more specific climate standard: a carbon reduction pathway. Its expense ratio is on the low side within its category.

Because the portfolio centers on US large- and mid-cap stocks, it tends to move in a direction similar to the underlying MSCI USA Index. The climate filter reduces some energy and utilities weight, so its sector composition may differ from the broader market.

Institutional and pension fund interest in ESG and climate themes continues, and capital inflows into the Paris-aligned ETF category have persisted. However, supply and demand may be affected by the interest rate environment and changes in ESG regulation.

Its strengths are the Paris Agreement climate standard and a low expense ratio, while its weaknesses are sector deviations from general market indexes and climate policy risk.

ESGU, ESGV, DSI, and SUSA shown in the table are comparison targets in the same ESG and responsible investing category, and they apply broader ESG criteria than alignment with the Paris carbon pathway. USCA is a US climate-themed ETF with similar positioning. You may also consider LCTU, which specializes in decarbonization strategies, and CRBN, which broadly covers global carbon reduction themes.

Here are the points to check before investing in PABU. It is important to review in advance how the Paris Agreement carbon reduction pathway alignment is applied, as well as the sector composition differences and the expense ratio.

Changes in climate policy direction or the ESG regulatory environment may affect index composition and supply and demand. In addition, sector deviations resulting from reduced exposure to carbon-intensive industries can create short-term performance differences.

It is a suitable choice for investors who want to build a US equity portfolio consistent with the Paris Agreement carbon reduction pathway at a low cost. Because it applies a more specific climate goal than general ESG ETFs, it is useful for investors with clear climate investing principles.