[Patents] Very basic patent question

[moeller@scireview.de (Erik Moeller)]

Hi,

if a company holds a patent on an essential technology, and another company 
wants to be active in the same field, can the other 
company sue the patent-holder to get the patent declared invalid, before 
starting to work on an actual product, or does it have 
to be sued by the patent-holding company to get the patent contested in court?

Thanks,

Erik Moeller
-- 
Scientific Reviewer, Freelancer, Humanist -- Berlin/Germany
Phone: +49-30-45491008 - Web: <http://www.humanist.de/erik>
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