In a rare moment of unity, Telstra, Optus, and Vodafone are fighting against a claim that their mobile networks infringe patents in how customers' mobile phones are tracked on mobile networks.
The case was brought against the three telcos at the end of 2013, with Brisbane-based video and sat-nav company Voxson alleging that the mobile network operators are infringing on two patents held by the company since the early '90s.
The first patent, Vox 1, forms the basis for the assisted GPS standard telecommunications that companies use to pinpoint the location of mobile users.
The second patent, Vox 2, covers the transmission of video signals over telephone networks.
Voxson alleges that the three mobile companies have been infringing on the use of the two patents in the daily running of their mobile networks, from users accessing their location in maps apps to using video chat services including FaceTime and Skype, to even simply watching videos online through YouTube.
The allegations cover the 2G, 3G, and 4G networks of all three carriers.
In the case of Vox 1, Voxson alleges that the telcos are required to use the patents in order to comply with the standards that make GPS technology interoperable between various carriers across the globe.
All three telcos reject the claims, and in a hearing in Sydney on Tuesday were united in attempting to have the claim struck out.
"Given this is the subject of legal proceedings, we are only able to confirm that we are vigorously defending our position against what we believe to be unjustified claims," a spokesperson for Optus told ZDNet.
ZDNet understands that the three telcos are disputing the methods of implementing these patents.
Justice Annabelle Bennett is hearing the case. Bennett also heard the long-running Apple-Samsung patent dispute stemming back to 2011, before it was finally dropped by the two tech giants in 2014.
Bennett, who specialised in intellectual property law prior to being appointed to the Federal Court in 2003, told Voxson that she believes the patents should still be considered despite the fact that many of the technologies at the centre of the case were not conceived when Voxson filed the patents.
"The Patents Act has to deal with changing technologies. It has got to be done using existing concepts and applying them to new technologies," she said.
The telcos have argued that Voxson will need to be more specific with its cases of alleged infringement before the hearing can proceed. Bennett indicated on Tuesday that more hearings would take place within the next few weeks.