The land was categorised as sensitive because it was non-urban with an area greater than 5ha. One of the properties also adjoined the foreshore at Kauri Bay and Auckland's Kahuru Point.
The judgement also revealed that Mai, a Chinese citizen, was a friend and de facto husband respectively of the two CKRL owners. He is considered to have been an overseas person at all relevant times, as he did not ordinarily reside in New Zealand.
Under the Overseas Investment Act 2005, overseas investors must get consent from the Overseas Investment Office (OIO) before purchasing sensitive land. It is also an offence for an associate of an overseas person to give effect to an overseas investment without such consent.
The judgment found CKRL was "subject to the direction, control or influence of an overseas person" in acquiring the Clevedon Properties, and therefore was an "associate" of an overseas person.
CKRL admitted it had failed to seek consent when acting as Mai's associate in purchasing the land, in breach of the Overseas Investment Act.
Justice Katz said their culpability was not "materially reduced" by the fact that it had acted as an associate.
Katz said there was a strong need to deter breaches of the Act by associates of people overseas, as such breaches could "alienate sensitive New Zealand land" in a way that was more difficult to detect.
OIO Group manager Anna Wilson-Farrell said the regulator would pursue associates no differently to overseas investors who directly made purchases.
"It is a privilege for overseas people to invest in New Zealand and we will continue to investigate when investors fail to seek consent to buy sensitive land.
"This is the eleventh case in which the court has awarded penalties for the purchase of sensitive land without consent.
"We will continue to focus on the use of associate relationships as part of our ongoing compliance efforts, and we will take enforcement action whenever we see a breach of the Act.
"The court decision recognises this."
The judgement recognised CKRL had admitted liability for breaching the Act, and had engaged "constructively" with the regulator - the Chief Executive of Land Information New Zealand.