Software company Compuware is charging IBM with using its intellectual property and engaging in illegal tying of its technologies and anti-competitive practices, according to a lawsuit this week.

IBM spokeswoman Laura Keeton said the company declined to comment on the suit. Compuware, a software developer for mainframe computers, has three main complaints against the dominant mainframe maker.

One is that IBM has stolen and used parts of copyrighted software code in IBM's File Manager and Fault Analyzer product. IBM has allegedly even copied material from Compuware's manual on the subject.

Compuware has also accused IBM of anti-competitive practices, including cutting off Compuware and other independent software vendors from information they need to develop their products.

IBM once had a deal with Compuware and other companies to provide them with information to develop software, but now, competition between the companies has "severely restricted the free flow of this information," Compuware said in its press release.

IBM has engaged in unlawful tying in violation of the Sherman Antitrust Act, by tying the purchase of software for mainframes to the purchase of its own software, Compuware said. The lawsuit harkens back to the 1970s when IBM was a frequent target of antitrust regulators.

"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," Compuware president Joseph Nathan said in a company release.

"Our applications provide faster, better and more cost-effective software solutions to help mainframe and distributed computer systems work more efficiently and effectively," Nathan added.

Lawsuits for anti-competitive practices have become common in the tech sector, as smaller players challenge the companies who hold a monopoly in their field. Sun brought a suit against Microsoft earlier this month, in an attempt to force it to release the underlying source code for Internet Explorer and separate Windows from other Microsoft software.

Among the specific charges levelled in Compuware's complaint:

• "IBM is also using its monopoly power in the sale of mainframe computers and related software to subvert competition on the merits," Compuware said. The company alleges that IBM is undermining development efforts by withholding information, tying the licensing of its monopoly software to mainframe software tools, and "using its position operating the information technology departments of thousands of major corporations to steer their purchases of the mainframe software tools."

• Compuware also alleges that there's a conflict between IBM's services unit telling customers to use Big Blue hardware and software--notably IBM's mainframe software. "It is impossible for a third party to supply mainframe software without the cooperation of IBM," Compuware said.

• Compuware said IBM didn't compete with its tools until "at least 1999" when Big Blue entered the market. "IBM's actual strategy was to create further dependence by its customers on the IBM line of products, thereby unlawfully extending IBM's already formidable monopolies," Compuware said.

  In an effort to get some of its tools to market, Compuware alleges IBM and its third-party vendors "elected simply to copy, among other things, portions of Compuware's source code for its File-AID IMS product and to copy and paraphrase large passages of Compuware's user documentation."

  News.com's Stephen Shankland contributed to this report.
  

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