Microsoft’s Bill Gates has taken the witness stand in a billion-dollar antitrust lawsuit accusing the software maker of duping a competitor prior to its Windows 95 rollout.

Mr. Gates arrived early Monday morning at the Salt Lake City federal courthouse, where he’s the first witness in his company’s defence.

Utah-based Novell says Microsoft tricked them into thinking its WordPerfect writing application would be included in the Windows 95 rollout. Novell says it was later forced to sell WordPerfect for a $1.2 billion loss.

Mr. Gates is the first witness as Microsoft presents its side of the case.

Microsoft lawyers say Mr. Gates dumped WordPerfect because it threatened to crash Windows 95 and wouldn’t be compatible with future versions.

Novell claims it was tricked, but Microsoft lawyers say the claims are groundless.

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