Assets under management rose 6% to £13.3bn in the six months to March, helped by interest in funds such as Global Women’s World Leadership and a strong performance by Global Opportunity’s fund.
Net inflows were £887mln and Ian Simm, chief executive, said it had benefitted from its long-term backing of green and sustainable technologies.
At the end of April, funds under management had risen further to £13.7bn.
“Developed over two decades, Impax's specialist expertise as investors in the transition to a more sustainable economy is resonating with a range of asset owners around the world,” Simm said.
Global Opportunities, a broad-based equity fund, was the best performer with the funds acquired in 2018 with the Pax World Group and fixed income the areas that saw outflows.
Shares, though, eased 5% to 265p despite the strong operating performance as Peel Hunt noted the weak performance of environmental funds in general during May.
Green indices dropped by around 8% said the broker, though it added investor interest remains high and Impax has several significant new accounts set to launch.
The broker also raised its price target to 290p although its investment recommendation was lowered to ‘add’ from ‘buy’.
Interim revenues rose 32% to £33.8mln reflecting the addition of Pax, but lower margins here held back underlying profits, which were flat at £7.7mln.
The interim dividend rises to 1.5p from 1.1p.