Novell has spent a month arguing that Microsoft was trying to protect its Windows monopoly when it rejected the WordPerfect writing application for the Windows '95 rollout.
Novell says it was forced to sell WordPerfect for a $1.2 billion loss two years later as Microsoft's own office programs gained market share.
Now it's Microsoft's turn to defend itself before the jury.
First, however, the company will ask a judge Friday to toss out the Novell complaint as groundless.
U.S. District Court Judge Frederick Motz has set aside an entire day for arguments.
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