If you are invalidating a patent is their a fee? How long does it take?
I am not sure about the fees, but it's a mind-bending process and can take several days if companies didn't find a good lead. I was stumbling upon some case studies of invalidation searches and found an article of a company. The article shows how they cracked an invalidation case and generated a good lead. That might help you understand how the whole process can vary in time. Here you go - INVALIDATION SEARCH – HOW WE CRACKED THE TOUGHEST CASE WE CAME ACROSS Based on resources and search criteria fees may vary.