Comment Blame the law, not PCI-SIG (Score 3, Informative) 689
The core of the problem is that PCI-SIG has little choice under trademark law -- unless they vigorously persue all infringement, they can potentially lose their trademark. Under trademark law, if the trademark holder knows of infringement and allows it, they loosen their grip on the trademark.
As an extreme example, if PCI-SIG did not pursue it legally in this case, and a few other cases, someone could re-assign pins on the PCI connector, and call their device a "PCI" card. When PCI-SIG went after them, the infringing firm could claim that "PCI" had become a generic term due to PCI-SIG's lack of protecting their trademark, and potentially win the case.
That's why phrases like "xerox machine" or "styrofoam cooler" sometimes result in C&D letters. It's not necessarily that Xerox does not want its name to be synonymous with copiers, but rather they must protect their trademark or lose it.
As an extreme example, if PCI-SIG did not pursue it legally in this case, and a few other cases, someone could re-assign pins on the PCI connector, and call their device a "PCI" card. When PCI-SIG went after them, the infringing firm could claim that "PCI" had become a generic term due to PCI-SIG's lack of protecting their trademark, and potentially win the case.
That's why phrases like "xerox machine" or "styrofoam cooler" sometimes result in C&D letters. It's not necessarily that Xerox does not want its name to be synonymous with copiers, but rather they must protect their trademark or lose it.
