A month after, PSI has filed a countersuit that denies the charges and accuses Big Blue of abusing a monopoly in mainframe servers. PSI sells technology that lets Itanium-based machines run IBM's z/OS mainframe operating system and other software. IBM didn't immediately respond to requests for comment.
"In an effort to eliminate consumer choice and destroy the only viable source of competition to its own mainframe computers, IBM is tying its mainframe computers to its mainframe operating systems by conditioning the sale of its operating systems upon the purchase or continued use of an IBM mainframe computer," PSI said in its suit.
And in a statement, Christian Reilly, PSI's vice president of product management and marketing added, "What IBM is trying to do here would be the equivalent to a hypothetical situation in which Microsoft had monopoly power in the markets for both PCs and PC operating systems and then refused to license Windows to HP, Dell, or other PC manufacturers to maintain and sustain its monopoly position."