I saw down below where someone was asking how long we have to invalidate or send in a submission of a patent up to 6 months after it is published. Does that mean that 3rd parties can not go back and invalidate patents from years ago that never should have been awarded? Some of those most egregious lawsuits involved patents that have been published for quite some time now.

As an example back around April a company called World Inc. started suing major video game companies like Blizzard, regarding patents 8,082,501, 7,493,558, 7,945,856 and 7,181,690 "System and Method for Enabling Users to Interact in a Virtual Space".(original filing, November 1995).

Virtual reality systems to the best of my knowledge were being developed and tested before November 1995(see the guys at VRML - April 1995, but started work in 1994) not to mention many games, although while primitive also used various aspects of what they are claiming. See CitySpace (1993, SIGGRAPH 1994), various Text Based (MUDS), Wolfenstein 3D(July 1995), Worlds Away(September 1995)

I mean you could take their claim and argue that they own the rights to things that every MMPORG has done in the last 20 years. Theres also a lot of other games and other pieces of the games that i mentioned that were using 2D. Just because you go from 2D to 3D, I could argue, doesn't mean that it's a clear invention either.

  • 4
    Would you mind editing this with some concrete discussion points and perhaps a specific example to back up the general feeling that the process is broken?
    – bmike
    Sep 20, 2012 at 15:28
  • 2
    your wish is my command :) i edited my original post.
    – geeksweep
    Sep 20, 2012 at 16:14
  • I recommend that you post the specific call for prior art as a new question. The original question ("Can we invalidate older patents") has been answered, and asking a different question here buries it.
    – Rob Napier
    Sep 20, 2012 at 16:19
  • thanks for the good point. I have made a new post regarding this. :)
    – geeksweep
    Sep 20, 2012 at 16:24
  • I think this is a duplicate of patents.stackexchange.com/questions/587/… Oct 4, 2012 at 15:34

2 Answers 2


Yes, there is a process for invalidating older patents. It is called reexamination. However, the process is costly (~$16k in filing fees) and somewhat complex. Provided you have the killer prior art that is needed to invalidate a patent, you will need more skin in the game than simple indignation to go this route.

But you can still ask for or post prior art and potentially make a difference.

Even thought you can't just submit that for free on a granted patent, you make it a bit easier for the folks that do have skin in the game by sharing what you have on the problematic patent(s). That way, if someone is sued for infringing, they'll be armed with what they need to defend themselves.

  • i just edited my post above - I think I have a strong case and I bet I could come up with even more examples if i searched my brain(and the interwebs) enough.
    – geeksweep
    Sep 20, 2012 at 16:14

Yes. An issued patent is presumed to be valid, but a challenger can produce prior art to demonstrate that the claims of the patent were anticipated or rendered obvious.

There are administrative post-grant procedures for challenging an issued patent, and, of course, anyone who is sued by a patent holder can support a defense of invalidity by producing prior art - even possibly art that was originally considered by the Patent Office when the patent was issued.

Source: If a patent has been issued, can it still be invalidated by prior art?

That said, the America Invents Act does create a new avenue for challenging patents, albeit a limited one. It allows third parties to introduce evidence of so-called “prior art” (proof the invention had already been invented) to block patents from being issued, and it also introduces a new framework to challenge patents in a “post-grant review” process.

Source: http://www.wired.com/threatlevel/2011/09/obama-signs-patent-reform-bill-crustless-sandwich-still-patented

  • So how does that new “post-grant review” process work?
    – Pacerier
    Jun 5, 2014 at 2:11

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .