Steam could pay more than £600m after allegedly ripping off millions of PC gamers

, a lawsuit has been filed with the UK’s Competition Appeal Tribunal against Valve, accusing it of market dominance and overcharging UK consumers.

Digital rights campaigner Vicki Shotbolt who has brought forth the lawsuit says: “Valve is rigging the market and taking advantage of UK gamers.”

The lawsuit claims that Valve charges an “excessive commission of 30%” and that the costs have been wrongfully passed on to gamers.

This commission is how much money Valve takes for every purchase made by customers via Steam.

So for every £10/$10 purchase made via Steam, Valve will earn £3/$3 from that purchase, and the publisher or developer will earn £7/$7.

By contrast, Epic Games Store charges just a 12% commission from sales.

Other storefronts have variable rates. The App Store earns 30% from most purchases, but charges a lower commission of 10-15% for smaller studios and publishers.

Google Play charges 15% for earnings under $1million but 30% after this.

While a 30% commission is the standard for some of these services, there are usually exceptions made for smaller games.

Shotbolt claims that the lawsuit has been filed “to stop this unlawful conduct and help people get back what they are owed.”

Valve is being sued for £656million ($830million) for reportedly overcharging the UK’s 14million consumers.

Valve has not responded to the lawsuit, or made a comment at the time of writing.

If you want to read more about Steam, check out the games revealed at the Future Games Show.