Vector has spoken publicly for the first time about a private prosecution it has brought against a company which it believes "behaved fraudulently in carrying out a significant project."
There are heavy secrecy orders over the case, which will not come to trial until October 2020.
The lines company said in a statement the amount which is the subject of the charges exceeds $1 million.
"This followed a whistle-blower from the company raising serious concerns with Vector."
"Vector has taken this action because it strongly believes that if this type of illicit conduct is left unchecked it leads to inflated infrastructure costs which in turn flow through to electricity prices for Auckland energy consumers, who are Vector's majority beneficial owners."