If a minor is included as a shareholder of the company then they must feature as an associate for the purpose of obtaining an ABN. Company directors must be at least 18 years of age.
Each associate must provide their TFN in the ABN application. If an associate does not have one and they are an Australian citizen then they must first apply for one. There is no minimum age specification for TFN application either.
It is understood that all members of a company have issued written consent to validate their inclusion as a company officeholder. If a minor is incapable of providing and comprehending this requirement, he/she should not be involved in the company structure.