[Patents] Very basic patent question

[phm@a2e.de (PILCH Hartmut)]

> 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?

Why should the patent be invalid?

The fact that it is "essential" and might block a whole field doesn't make
it any less valid.

-- 
Hartmut Pilch                                         http://phm.ffii.org/
Protecting Innovation against Patent Inflation      http://swpat.ffii.org/
98000 signatures against software patents       http://www.noepatents.org/