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Impax Parent Rating

Above Average

UK-listed sustainable investing boutique Impax was founded in 1998 and has since been truly dedicated to sustainable investing.

The firm's assets under management increased steadily and organically over the first two decades, but in recent years the pace of growth has accelerated, driven by the acquisition of US-based Pax World Management in January 2018 and investor demand. While the firm managed around GBP 8.2 billion at the end of 2017, its AUM stood at almost 5 times that amount at GBP 38.9 billion as of May 2023. Impax has successfully integrated Pax World Management, rebranding the Pax funds to the Impax label at the end of December 2022. The rapid growth has been solidly digested by investing in risk-management and compliance functions. The firm also continued to invest in its listed equity team, which manages around 95% of assets. The team is a very stable and solid mix of industry veterans and up-and-coming talent and generally boasts strong investment and sustainability expertise and a very strong investment culture. With several strategies nearing their maximum capacity, it was comforting to see the firm's good investor stewardship when it soft-closed the small-and mid-cap-focused Specialists strategy in July 2020. Historically, Impax has lacked a meaningful global distribution capability of its own. This was addressed through partnerships, most notably with BNP Paribas. While this model will keep playing an important role, the firm has invested heavily to increasingly take control of the distribution of its funds. Impax is set for future growth, which can be driven by existing funds, but it will also launch new strategies, as exemplified by the launch of infrastructure strategies in 2021 and 2022 and the firm's quest to build out its fixed-income capabilities. Fund launches have always been within the proven competencies of the firm, and we would like to see that continue. Finally, we think the firm generally charges reasonable fees, but it can still attempt to share economies of scale with investors via lower fee levels.

Impax Investments


US Open-end ex MM ex FoF ex Feeder

Total Net Assets

8.56 Bil

Investment Flows (TTM)

−689.58 Mil

Asset Growth Rate (TTM)


# of Share Classes

Morningstar Rating # of Share Classes
Not Rated 2

Morningstar Mentions

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