Half of the board of directors in Chorus Limited must be New Zealand citizens, per company statute.
"Half of Board to be New Zealand citizens
17.4  A person who is not a New Zealand citizen shall not be eligible for appointment or election as a director if, immediately after his or her appointment or election as such, the number of directors who are New Zealand citizens would be less than one half of the total number of directors then in office.
17.5  If at any time the number of directors who are New Zealand citizens is reduced below one half of the total number of directors then in office, the Board shall ensure (whether by exercising its powers under clause 17.12 or otherwise) that within two months of the date of that reduction, sufficient directors are appointed so that not less than one half of the total number of directors then in office are New Zealand citizens.[...]" (Constitution of Chorus Limited [accessed on 13.10.2021], Part C, Clauses 17.4 and 17.5)
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"This Deed is made on 11 November 2011
between Chorus Limited (Chorus)
and Her Majesty the Queen in right of New Zealand (the Crown)
Introduction [...]
C. Chorus, a New Zealand's public company focusing on the supply of fixed access and aggregation services in New Zealand, was created out of the demerger of Telecom Corporation of New Zealand Limited (TCNZ).
D. Pursuant to the Transaction Documents, Chorus has agreed to build and operate the Network in the Coverage Area and CFH will provide certain funding to Chorus for that purpose.
It is agreed 
[...]
4. Chorus' Constitution
4.1 Chorus represents and warrants for the benefit of the Crown that on the date of the Final Court Orders, Chorus adopted the Constitution. The Crown acknowledges that it has approved the form of the Relevant Constitutional Provisions in the Constitution.
4.2 Chorus must, and must procure that the Chorus directors and employees, at all times comply with the Relevant Constitutional Provisions.
4.3 Without limiting any other provision of this Deed, including clause 4.2, Chorus must, and must procure that the Board will, take all action permitted by the Constitution so as to ensure that:
(a) no person shall have a relevant interest in 10 percent or more of the total voting share for the time being without, and except in accordance with the terms of, the prior written approvals of the Crown given under this Deed; or
(b) no person who is not a New Zealand national shall have a relevant interest in more than 49.9 percent of the total voting shares for the time being without, and except in accordance with the terms of, the prior written approvals of the Crown given under this Deed [...]" (Deed of Operation and Governance Undertakings, 2011)
Constitution of Chorus Limited [accessed on 13.10.2021], Part C, Clauses 17.4 and 17.5
Deed of Operation and Governance Undertakings, 2011
[<a href="https://company.chorus.co.nz/governance">Statute</a>],[<a href="https://company.chorus.co.nz/governance">Deed</a>]