The Labour and Green parties have scored an early win by forcing the Government to file a supplementary disclosure on the Mighty River Power offer document.
The document was lodged with the Registrar of Financial Service Providers yesterday afternoon.
The supplementary disclosure became necessary after the main opposition parties launched an electricity policy that sent shock waves through the industry. They are proposing to implement a single-buyer model - NZ Power - that would do away with the wholesale electricity market.
Finance Minister Bill English said the existing MRP offer document already outlined the principal risks associated with an investment in MRP shares. That covered the risk that changes in the regulatory environment, including for the wholesale or retail electricity market, might affect the company.
However, the Government received advice that the recent Labour-Greens proposal, if they were elected, to effectively replace competition with a state agency to act as a single buyer of wholesale electricity from generators could be material to decisions to invest in MRP shares, he said.
''Our advice is also that if Labour-Greens had announced this policy before the offer began, their announcement would have been referred to in the offer document submitted to the Financial Markets Authority.''
The supplementary disclosure set out the additional information so that prospective investors could factor that into their decision-making, Mr English said.
The share offer website was temporarily suspended while the supplementary disclosure was added and was set to open just after midnight; but all other details of the offer were to remain the same.
Investors who had already applied for shares were able to withdraw their application if they wished, until May 1.
The closing of the offer also remained at 5pm Friday, May 3.
Green Party energy spokesman Gareth Hughes said the Government needed to make sure Kiwis had full and up-to-date information when it asked them to buy MRP shares.
''Mighty River's document needs to reflect the impact that NZ Power will have on the company. When NZ Power forces power prices down to a fair level, saving families $300 a year, there will be a consequent downward movement in the company's profits,'' he said.
Anyone considering investing in MRP needed to know the Greens would tackle its ''excessive'' profits, Mr Hughes said. MRP would still be profitable, but it would not get away with charging exorbitant prices for cheaply-produced electricity.
''The Greens launched this plan before the Mighty River sale so potential investors would have fair warning of these changes. The Government and Mighty River now need to ensure those potential buyers are adequately informed,'' he said.
