Foreign persons may hold an aggregate of 35% (5% for individual investors) of the shares of Telstra. By 'foreign persons' is notably understood foreign citizens not ordinarily resident in Australia, or companies where foreign citizens not ordinarily resident in Australia hold a particular type of stake in the company of not less than 15% individually or not less than 40% in aggregate.
"8BG  Meaning of unacceptable foreign‑ownership situation
For the purposes of this Act, an unacceptable foreign‑ownership situation exists in relation to Telstra if:
(a)  there is a group of foreign persons who hold, in total, a particular type of stake in Telstra of more than 35%; or
(b)  there is or are one or more foreign persons each of whom holds a particular type of stake in Telstra of more than 5%.
[...]
8BI  Compliance by Telstra
(1)  Telstra must take all reasonable steps to ensure that an unacceptable foreign‑ownership situation does not exist in relation to Telstra.
[...]
Schedule—Ownership definitions
2  Definitions
(1)  In Part 2A and this Schedule, unless the contrary intention appears: [...]
foreign citizen means an individual who is not an Australian citizen.
foreign company means a company incorporated outside Australia.
foreign person means:
(a)  a foreign citizen not ordinarily resident in Australia; or
(b)  a company where:
(i)  a foreign citizen not ordinarily resident in Australia; or
(ii)  a foreign company;
holds a particular type of stake in the company of 15% or more; or
(c)  a company where a group of 2 or more persons, each of whom is either:
(i)  a foreign citizen not ordinarily resident in Australia; or
(ii)  a foreign company;
holds, in total, a particular type of stake in the company of 40% or more; or
(d)  the trustee of a trust estate in which a foreign citizen not ordinarily resident in Australia or a foreign company holds a substantial interest; or
(e)  the trustee of a trust estate in which 2 or more persons, each of whom is either a foreign citizen not ordinarily resident in Australia or a foreign company, hold an aggregate substantial interest.[...]" (Telstra Corporation Act 1991 (Act No. 79 of 1991), last amended by Communications Legislation Amendment (Deregulation and Other Measures) Act 2019 on 12 December 2019, Sections 8BG, 8BI and Schedule, Section 2)
Telstra Corporation Act 1991 (Act No. 79 of 1991), last amended by Communications Legislation Amendment (Deregulation and Other Measures) Act 2019 on 12 December 2019, Sections 8BG, 8BI and Schedule, Section 2
[<a href="https://www.legislation.gov.au/Details/C2020C00011">Act</a>]