The Telecommunications Users Association (TUANZ) wants market authorities to investigate unusual movements in Chorus's share price.
TUANZ says it will write to the New Zealand Stock Exchange (NZX), the Financial Markets Authority(FMA) and the State Services Commission on Tuesday calling for an inquriy.
The association says on Friday, when a report into the financial viability of the telecommunications company was received by the Government but not released publicly, shares in Chorus jumped by 10 cents, or more than 7%,
The Ernst & Young Australia report was released on Saturday, and on Monday the shares closed 4 cents lower.
TUANZ chief executive Paul Brislen says a similar trading pattern has been observed at other times that Communications Minister Amy Adams has made major announcements.
Mr Brislen said the association is not making any accusations against anyone, but said many hundreds of millions of dollars are at stake.
He said the strange price movements in Chorus shares over the last year merit investigation by the NZX and FMA in order to assure everyone that no insider trading has occurred.
Ms Adams said if TUANZ has evidence of wrongdoing, it should present it, and she would hope it did have evidence before making such allegations.
The Financial Markets Authority said it has received one complaint about the trading of Chorus shares on Friday which it will look into in conjunction with NZX as the frontline regulator of the markets it operates. It will respond to TUANZ once it has received their letter.
The State Services Commission said it will respond accordingly when it receives the letter, while the NZX said it did not comment on regulatory matters relating to particular issuers.