According to the Companies site
http://www.business.govt.nz/companies who list the biggest 10 shareholders (at last update anyway) the two biggest shareholders are:
Allocation 1:186946448 shares (39.69%)
NEW ZEALAND CENTRAL SECURITIES DEPOSITORY LIMITED (the Reserve Bank)
2 The Terrace, Wellington , New Zealand
Allocation 2:74702524 shares (15.86%)
CROWN FIBRE HOLDINGS LIMITED (Minister of Finance and Minister of State Owned Enterprises)
C/- Bell Gully, Level 22, Vero Centre, 48 Shortland Street, Auckland, Null, 1010 , New Zealand
If this is correct surely the Government/Taxpayers own 55.55% of Chorus? Or am I missing something here?