New Zealand's stock market operator, NZX, and the Treasury say there's nothing untoward in government-controlled listed companies providing the Government with monthly financial reports.
Mighty River Power, Air New Zealand and Meridian's results are included in the Government's monthly accounts.
Ordinary shareholders get only quarterly or half yearly reports, and at least one fund manager has suggested this is not right.
But the NZX says companies don't have to share every piece of information with all shareholders to ensure fair, orderly and transparent markets.
It says retail investors are protected by rules ensuring price-senstive information is publicly released and by insider trading laws.
Treasury says only a handful of its officials see the information and those employees have to sign legal documents agreeing not to trade shares.