Datel has filed a lawsuit the US alleging that Microsoft deliberately altered its technology to force the UK-based firm's Max Memory cards out of the market.

The anti-trust complaint in a San Francisco federal court came after Microsoft's Dashboard update made third-party memory cards useless.

Mike Connors, Datel's founder, said: "For many years, Datel has brought to the public products that offer more capacity, extra functionality or other game enhancing features with the aim of offering a reasonably priced alternative to first-party accessories.

"The Max Memory card plugs into the Xbox 360 and allows a user to store games, characters, and similar information."

He added that it offered game information transport between Xbox systems.

"The Microsoft memory card does exactly the same thing, with the difference that it offers only one-quarter the memory while listing for the same retail price. Datel engineered the Max Memory card to be 100% compatible and over 50,000 Max Memory cards have been sold without a single report of harm to the Xbox console."

Microsoft's recent upgrade also makes Twitter and Facebook available on Xbox 360. Mr Connors previously criticised the upgrade as it would "prevent customers from exercising their freedom of choice".

In the lawsuit, Datel argued that Microsoft's first-party products are more expensive than Datel's, while offering less memory.

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