“Microsoft has taken steps to render inoperable the competing Datel memory card for no visible purpose other than to have that market entirely to themselves,” Datel attorney Marty Glick explained in a press release. “They accomplished their recent update by making a system change that will not recognize or allow operation of a memory card with greater capacity than their own. We believe that with the power Microsoft enjoys in the market for Xbox accessories this conduct is unlawful.”

In the press release, Datel goes on to say that the lawsuit is intended to “restore competition” which, the company suggests, is beneficial to consumers. It’s now up to a federal court in San Francisco to determine whether the Max Memory-crippling Xbox update constitutes unlawful anti-competitive behavior on the part of Microsoft.

The last time Datel went to court, it viewed the experience from the other side. Sony filed suit against the peripheral maker over the “Lite Blue Tool,” which would have enabled users to run unsigned code on PSP hardware.