The suit charges Amazon.com, BarnesandNoble.com, Netflix and Overstock.com, whose online marketing programmes incorporate these patented technologies, with infringement of United States Patent Number 5,717,860. The suit also charges Amazon.com and BarnesandNoble.com with infringement of United States Patent Number 5,712,979. BTG owns these patents and is represented by the law firm of Robins, Kaplan, Miller & Ciresi, L.L.P. The suit asks for unspecified damages for past infringing activity and an injunction against future use of the technology. BTG has filed the suit following its efforts to reach an agreement to sell or license the patents to Amazon.com, BarnesandNoble.com, Netflix and Overstock.com on commercially reasonable terms.

The 5,717,860 and 5,712,979 patents were granted by the US Patent and Trademark Office in 1998, and were acquired by BTG in 2002. The technology was developed by Infonautics Corp., a pioneering provider of personalised web-based information agents and Internet sites. Infonautics, founded in 1992, created one of the first comprehensive, subscription-based online information resources on the Internet. The technology enables the efficient tracking of the movement of Internet users between websites and is used in certain online marketing programmes.

Ian Harvey, BTG's Chief Executive Officer, commented: "We believe the patents are fundamental to the tracking of users for the online marketing programmes used by Amazon.com, BarnesandNoble.com, Netflix and Overstock.com, and that the commercial potential of the patents is significant.”

Contacts:

Andy Burrows (UK IR, UK Media)
BTG
+44 207 575 1741
andy.burrows@btgplc.com

Ben Atwell (UK Media)
Financial Dynamics
+44 207 831 3113

Scott Williams (Business, US Media)
BTG
+ 1 610 943 3551
scott.williams@btgplc.com

About BTG
BTG is an intellectual property and technology commercialisation company that operates internationally. BTG creates value by investing in intellectual property and technology development, and in early stage ventures. We realise value through technology licensing, patent assertion and sale of equity investments. Through a multidisciplinary approach, we apply intellectual property and commercial expertise, together with specialist skills in science and technology, to create major product opportunities in the health and high tech sectors. BTG has commercialised important innovations, including Magnetic Resonance Imaging, working closely with Professor Sir Peter Mansfield, who was jointly awarded the 2003 Nobel Prize for Medicine, and others who made contributory inventions to MRI. BTG has also commercialised Multilevel Cell Memory, Campath® (alemtuzumab), the first monoclonal antibody treatment for chronic lymphocytic leukaemia, and recombinant Factor IX blood clotting protein. BTG operates through wholly owned subsidiaries BTG International Ltd and BTG International Inc in the UK and USA, respectively. Further information about BTG can be found at www.btgplc.com