Tivo, the developers of digital TV recorders, have won a patent for technology which can pause live television broadcasts, sending shares in the company soaring.

Shares in the company jumped 70% on Thursday and continued to climb on Friday to a $12.25 high on the New York stock exchange, although it remains a long way off its 52-week high of $37.50.

The leap in value was also driven by the addition of 35,000 new US subscribers to its service.

"We are pleased that Tivo is receiving formal recognition for the invention of unique and novel technologies - underpinning the making of Personal Video Recording devices," said Jim Barton, Tivo's chief technology officer.

Viewing habits

Personal video recorders are seen as the next generation of video recorders - machines which can store TV programmes digitally without the need for tapes and allow users to record and play at the same time.

A viewer can pause a programme at any point return to it at a later date and the machine continues to record so you do not miss the end of a show.

Tivo devices can also learn the viewing habits of users and record programmes it thinks you will like.

The technology has made little impact in the UK since it was launched more than six months ago and has about 250,000 subscribers in the US.

'Key component'

Tivo has long term plans to license its technology.

"Technology licensing has always been a key component of our strategy," said Mr Barton.

"It is in our interest to see the PVR category grow."

The company has called on Microsoft, which has a similar product called Ultimate TV, to check its patent carefully and to contact Tivo about possible licensing.

"Legal action is only one aspect of a licensing strategy," said Mr Barton.