In a suit filed before the federal Copyright Tribunal on Friday, The Copyright Agency will allege its members are owed millions in back pay for an estimated 200 million photocopies and other reproductions of newspaper, magazine and journal articles and photos by state public servants.

Writers, illustrators, journalists, academics and other holders of copyright join the agency which returns fees to them when their work has been reproduced or photocopied by institutions such as libraries and government agencies.

"For five years we have attempted to get the NSW Government to recognise the value in tens of millions of pages of author, publisher, researcher, photographer, cartoonist and journalist content," said Copyright Agency CEO Adam Suckling.

"Thousands of NSW executives and public servants have copied up to 200 million pages of copyright material without the appropriate approval or recompense.

"The NSW Government is the only government in Australia refusing to pay a fair rate."

The average Australian author makes about $13,000 from their work according to agency estimates.

Public servants copy work such as newspaper and magazine articles, academic journal articles, illustrations and photos in the course of their duties.

The agency's case argues if NSW paid the same compensation as all other state governments, it should owe $7.5 million in fees over the past five years.

But Fairfax understands the case alleges the state government is about $6 million short of that figure and has recently even allegedly suspended payments entirely.

NSW would make $1.5 million a year in copyright payments if it had the same fee structure as other states.

In late 2015 the government paid the agency about $500,000 per year for its previous three years' copyright fees but it is alleged to have since stopped paying the fees.

The agency also takes a fee from the money returned to authors.

But critics have recently said the agency itself has been diverting millions of dollars meant to be returned to its members to fund a campaign against a proposal for the introduction of "fair use" copyright laws in Australia, which would allow institutions such as universities to freely copy small amounts of text without paying fees.

The transparency of its accounts and retaining of money from "orphan authors" who cannot be traced, was also criticised by the Productivity Commission.

A spokeswoman for the NSW Department of Justice declined to comment on the alleged facts of the dispute but said the government was trying "to achieve a fair and equitable arrangement".

"As negotiations are commercially sensitive, it would be inappropriate to make any further comment," the spokeswoman said.

Disclosure: The author is a member of The Copyright Agency. Last year he received $155.66 for reproduction of his work via payments from that agency.