Pamela Jones, a paralegal who has closely followed the SCO v. Novell case since its beginning on her Groklaw blog, initially deemed this the end of the line. "It's over," she wrote on her site.

However, SCO could appeal the ruling. Also, as Jones noted later on her blog, a SCO spokesman told The Salt Lake Tribune that the company would continue its related lawsuit against IBM. SCO may drop the copyright infringement charges regarding Unix in the IBM case, but SCO has other claims related to contracts that it can assert against IBM, the spokesman is quoted as saying.

SCO's main telephone line went unanswered on Tuesday afternoon and the company had not posted a statement on its Web site.

SCO has lost many rulings in the dispute over the past couple of years. Linux users closely watch the case because they worry that if SCO prevails, they could face legal action too.

The battle dates back to 2003 when SCO sued IBM, claiming that it had violated SCO's rights by contributing Unix code to Linux. The following year, SCO sued Novell, saying that it falsely claimed rights to Unix.