Compuware has filed a lawsuit against IBM, alleging that the latter used the software tools developer's intellectual property in its mainframe products.
The suit also alleges unfair competition, unfair trade practices, and monopolistic practices.
Compuware is charging IBM with using its source code in its File Manager and Fault Analyser tools.
Compuware claims that IBM products have many features that are similar to its own products and contain limitations and bugs that provide strong indications that Compuware's source code was copied.
In addition, Compuware claims that Big Blue has steered its services customers to its own products without fair competition and has denied rival vendors necessary technical information on IBM hardware and software.
Joseph Nathan, Compuware president, said: "We have been considering this distressing issue for quite some time and regrettably concluded that Compuware was required to take this action in order to protect the interests of the company, its customers and its shareholders."
According to Nathan, IBM's strategy was to develop the tools to lower the cost to its customers which paid licensing and maintenance fees to third-party vendors.
The suit said: "IBM has attempted to enter the mainframe software tools market and compete with independent software vendors by misappropriating Compuware's source code and even copying our user manual."
Nathan explained that IBM's File Manager user manual contains numerous passages that are verbatim copies of Compuware's own manuals, including documentation of Compuware features not found in IBM's products.
He maintained that the company has been trying to talk to IBM for more than a year with no results.
"Our sole mission with the lawsuit is to ask the courts to require fair play in the marketplace so that mainframe customers are free to select the software tools that provide the best value and performance," said Nathan.
An IBM spokeswoman said that the company does not comment on pending litigation.
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