All directors involved in an Australian proprietary company must be at least 18 years of age.
Shareholders, also known as members, do not have to meet the above requirement. However, they do need to be able to understand their rights and responsibilities within the company and consent to the issue of shares.
A company can establish its own minimum age specification for members.
It is assumed that upon registration the member has given their written consent to become a shareholder in the new company.
N.B. In order to obtain an ABN all directors and shareholders will need to provide their TFN. If a minor does not have a TFN they will need to apply for one or alternatively, the member will need to be removed from their shareholding position. To do so you will need to contact ASIC directly and submit a Form 484.