The almost four-year long battle between TiVo and former sister companies Dish Network and EchoStar over DVR timeshifting technology rages on. The US Patent and Trademark Office has given a preliminary rejection to TiVo's software claims that could be used to find EchoStar in contempt of court and thus responsible for a billion dollar payout.

In the short term, EchoStar may be on course to avoid the contempt of court suit that would earn it huge legal penalties for allegedly disregarding the court's order to change its DVRs so they no longer infringed upon TiVo's patents.

"We are pleased that the Patent and Trademark Office (PTO) issued an initial office action rejecting Tivo's software claims as invalid in light of two prior patents," reads a statement from Dish Network and EchoStar today.  "These software claims are the same claims that EchoStar was found to have infringed in the contempt ruling now pending on appeal. We believe that the PTO's conclusions are highly relevant to the issues on appeal as well as the pending sanctions proceedings in the district court."

TiVo, however, believes the ruling is just business as usual.

In a statement today, TiVo said, "This is an initial step in the lengthy process known as 'reexamination,' and it is not unusual for the PTO to provide a preliminary finding of invalidity and to then later find that the claims are valid after hearing an explanation from the patent owner. Indeed, this is precisely what happened with the first reexamination of the Barton Patent that EchoStar filed in 2005. Among other things, the next step in the reexamination process provides TiVo, for the first time, the opportunity to discuss and distinguish the references presented by EchoStar, and to present new claims."