SCO sued IBM over patent infridgement on UNIX, claiming that UNIX dripped into LINUX code. However, Novell sued SCO over the rights of UNIX - and won. In response to the court loss - and a possible $30M pay off - SCO filed BK.
SCO tried a new business plan in 2003. Faced with competition from LINUX, SCO decides to litigate instead of compete. (We see this a lot in telecom and tech). Now with a court loss and declining revenue, few assets, and debt, it's not suer if even BK can save it.