The brainchild of entrepreneurs, Melbourne-based advertising executive George Tomeski and Sydney's Luke Bunbury, PlayUp was spruiked in Australia and internationally as a world first in mobile-based, sport-focused, social media.

It attracted tens of millions from a star-studded band of investors including Malcolm and Lucy Turnbull and son Alex, former Telstra chairman Bob Mansfield, pub and pokie king Bruce Mathieson and ex-test cricketers Adam Gilchrist and Steve Waugh.

Founded in 2006 as a possible online gambling app, PlayUp appeared to be in serious trouble by 2014 after burning through $75 million raised from investors between 2007 and 2011, including from BRW Rich listers Allan Myers, QC, John Higgins and funds manager David Paradice.

Documents lodged with the Victorian Supreme Court reveal that six former employees are seeking to wind up Revo, claiming they're owed $500,000 in unpaid wages and superannuation.

One of the company's shareholders, Ben Smith has joined the action, claiming $100,000 in the name of his personal superannuation fund.

The legal stoush is likely to resurrect questions about the company's finances and what, exactly, PlayUp offered to lure such a glitterati of backers.

Ostensibly, at least in one of its iterations, the PlayUp product was an app that allowed users to buy content from sports organisations, media and sports statistics firms, and athletes. An interactive mobile chat feature was to allow "fans to engage with friends and content around live sports".

But bemused observers have often speculated that PlayUp was really intended as a gambling enterprise, and that lucrative betting markets in Asia and Europe, including China, were to be its money spinner.

Malcolm Turnbull bought shares in 2012. In 2013, as shadow communications spokesman he denied any conflict of interest in owning shares in an interactive mobile phone sports company.

At the time he and Revo Pty Ltd both insisted PlayUp was not a gambling product, but a social networking platform for sports fans. Mr Turnbull cited a written assurance from Revo chair Nick Greiner that PlayUp was not a gambling service.

Mr Greiner chaired Revo Pty Ltd, the company behind PlayUp and the subject of the wind-up action, from 2008. But he resigned in early 2015, one of string of board resignations in late 2014 and early 2015 including Asciano director Geoff Kleeman, Mr Mathieson, Mr Mansfield and Justin Ho, son of Hong Kong based gaming magnate, Stanley Ho.

Nick Greiner and Alexander Turnbull remain shareholders, as does Goldman Sachs' Simon Rothery​. Malcolm and Lucy Turnbull no longer hold shares, and sold out amid financial turmoil in the company and after a Fairfax Media story highlighted potential conflicts of interest with his role as shadow communications minister.

In February 2015 PlayUp chief executive Mr Tomeski, told Fairfax Media that the the business broke even in financial year 2014 under Greiner's watch, but shareholders say they have not received a financial report for the 2014-15 year and less than a year later, the company's head office in Melbourne's Flinders St is closed, its websites are down, and the company contact number is permanently engaged. The PlayUp app no longer appears to function.

The application to the Victorian Supreme Court – in the name of former employee David Fitzpatrick – follows a successful wind-up action by former chief executive of the European PlayUp subsidiary, Sophie Neary.

She was employed for a year from March 2013 but PlayUp defaulted on payments to her from September that year.

PlayUp has also faced action in Australia from the Fair Work Ombudsman over unpaid wages to several staff members. And in May the Victorian Commission of State Revenue applied to have Revo wound up. It then withdrew, allowing the company to trade on.

Revo directors, George Tomeski and Luke Bunbury, have refused to speak to The Age about the company's current status. Revo's former financial director Michael Stocky also refused to comment, as did former company director Geoff Kleeman.