Aust Grand Prix 'volunteers' win payout

People who worked for free at the Australian Grand Prix have won back pay from a global labour hire giant.

Adecco brought in unpaid volunteers to work in customer service roles at the Australian Grand Prix in Melbourne in March, the Media Entertainment and Arts Alliance said on Sunday.

The company has now paid five workers a total of $3500 for their labour during the four-day event following a Fair Work Ombudsman's investigation after a tip off from the union.

"We're concerned that these revelations just scratch the surface," Adam Portelli, MEAA's Victoria and Tasmania regional director said in a statement.

"It's alarming that a multinational labour hire company thought it could get away with such blatant behaviour."

Another 18 people, directly recruited by the Australian Grand Prix Corporation, may also paid despite initially claiming they were "volunteers" or "interns."