The investors wrote to the Australian Stock Exchange (ASX) on Wednesday, saying that the proposed $8.75 billion acquisition of AZEK by James Hardie would significantly dilute interests of existing shareholders and "irreversibly change their rights" without any vote. The investors - which include top pension funds AustralianSuper and UniSuper and institutional investors Schroder Investment and Fidelity Australia - called on the ASX to make shareholder approval a condition for share issuance above a threshold as well as for modifications to listings. Some of the investors who have written to the ASX are shareholders in both James Hardie and AZEK.