Asterion Industrial Partners takes Southern Water stake

(by Karma Loveday)

Southern Water has secured a further £300m of equity investment, delivering in full the £1.2bn equity support package announced in July 2025.

The new investment comes from a consortium led by Macquarie Asset Management, alongside new investor Asterion Industrial Partners (AIP), an independent European infrastructure investment manager headquartered in Madrid with approximately $10bn of assets under management. AIP will provide the majority of the new capital, becoming a minority shareholder in the company.

The equity boost will support the delivery of the company’s £8.5bn AMP8 programme. It takes total equity invested in Southern Water to £2.8bn since Macquarie Asset Management's acquisition in 2021. Southern Water highlighted that no dividends have been paid to shareholders during this period.