It is alleged that Airservices, a federal government-owned organisation, systemically breached the Fair Work Act by failing to pay required salary increases, superannuation contributions, Christmas leave and redundancy entitlements to a number of employees.

The suit stemmed from the use of "personal management contracts" when Airservices staff were promoted following the introduction of the 2009 Fair Work Act, lawyers representing the employees said last year.

Staff allegedly signed away the terms of their existing enterprise agreements and their rights to better leave entitlements, redundancy payments and superannuation contributions when they accepted the management contracts.

The suit is being run by Chamberlains law firm on behalf of employees and funded by Augusta Ventures, a commercial litigation funder.

Chamberlains employment litigation director Rory Markham has previously said the suit could represent "the largest underpayment of workers by a Commonwealth body corporate in Australian history".

"[It] will demonstrate that not even the public service is immune from underpayments and breaches of basic employment conditions," Mr Markham said last year.

In addition to reclaiming alleged shortfalls in superannuation and other entitlements, employees would also seek to have financial penalties imposed on Airservices Australia, according to court documents.

"Breaches of employment agreements carry penalties of up to $52,000 per contravention," Mr Markham said last year.

Airservices Australia is the government entity responsible for air traffic control, fire fighting and navigation services at a number of federally-leased airports across the country.

An Airservices spokesman said the organisation would not comment on the case while it was before the court.

"However, we can assure you that the scope and number of the claims we are now aware of is a fraction of what was reported last year," the spokesman said.

"Airservices takes its obligations as an employer seriously, and will vigorously defend any claims that we find to be without substance, including pursuing costs where it is in our legal right to do so."

A spokeswoman for Airservices Australia said last year that the agency had a "total commitment" to its staff.

"Airservices Australia is, and always has been, a responsible employer and we ensure that every employee's rights and entitlements are met and protected," the spokeswoman said.

"We have a total commitment to our duty of care for all Airservices' employees.

The case will return to court for a directions hearing in February.