The Two Flavors of Invalidation: IPR vs. PGR
Both IPR and PGR are trial proceedings conducted before a panel of three Administrative Patent Judges (APJs). Unlike a random jury drawn from the local DMV line, these judges actually have technical backgrounds. If your patent relies on pseudo-scientific jargon to mask a lack of innovation, they will know. However, the two proceedings have very different rules of engagement.
1. Timing is Everything
- PGR: This is the early-bird special. You must file a PGR petition within the first 9 months after a patent is issued or reissued.
- IPR: This is the long game. You generally cannot file an IPR until the 9-month PGR window has slammed shut. Crucial trap: If you are sued for patent infringement in district court, you have exactly one year from the date you are served the complaint to file your IPR petition. Miss that deadline, and the PTAB doors are locked.
2. Grounds for Attack
- PGR (The Kitchen Sink): PGRs are broad. You can attack a patent on virtually any statutory ground. Is it not novel (102)? Is it obvious (103)? Is it an abstract idea pretending to be software (101)? Did the inventor fail to actually describe how to build the thing (112)? You can throw it all at the wall here.
- IPR (The Sniper Rifle): IPRs are strictly limited. You can only challenge the patent based on novelty (102) and obviousness (103), and your evidence is entirely restricted to prior art consisting of patents and printed publications. You cannot argue that the invention is an ineligible abstract concept, nor can you bring in a physical prototype as prior art.
3. The Trap of Estoppel
Estoppel is the legal system’s way of saying, “Speak now or forever hold your peace.” If the PTAB issues a Final Written Decision, you are barred from raising those same invalidity arguments in future district court or ITC proceedings.
- PGR Estoppel: Terrifyingly broad. You are barred from raising any ground you raised or “reasonably could have raised.” Because PGR allows for almost any invalidity argument, losing a PGR effectively strips you of most of your defenses in court.
- IPR Estoppel: Narrower, simply because you are statutorily limited to raising only 102 and 103 challenges based on printed publications.
4. The Price Tag
The PTAB is billed as a “cheaper” alternative to district court litigation. That is true, but only in the way that buying a Porsche is cheaper than buying a private jet. A PGR requires a $20,000 filing fee and a $27,500 post-institution fee. An IPR costs $19,000 to file and $22,500 if instituted. And that is just what you pay the government—factor in attorney fees, and you are easily looking at hundreds of thousands of dollars.
The Ultimate Showdown: PTAB vs. District Court
Why do challengers rush to the PTAB when they are already fighting in district court? Because the deck is heavily stacked in their favor.
Because these paths run parallel, defendants immediately ask the district court to pause (stay) the infringement lawsuit while the PTAB does its dirty work. If the PTAB kills the patent, the multi-million-dollar court case simply evaporates.
The 2025–2026 Reality Check: A Statistical Bloodbath
If you are a patent holder, the latest statistics might give you a mild panic attack, followed by a strange sense of relief, followed by another panic attack.
IPRs continue to absolutely dominate the landscape, accounting for about 95% of all PTAB petitions, with PGRs hovering around 5%. But the real story of the last couple of years is the wild swing in institution rates.
The Rise of the Discretionary Denial
The PTAB does not have to hear your case. They have the discretion to deny a petition, often because a parallel district court trial is moving too fast and the PTAB doesn’t want to duplicate efforts.
Over the course of 2025 and into 2026, under changing USPTO leadership, the use of these “discretionary denials” skyrocketed. In 2024, the institution rate (the percentage of petitions the PTAB agreed to hear) sat at a comfortable 68%. By early 2026, that overall institution rate had plummeted to around 37%.
If you’re a patent holder, this sounds like great news! The “Death Squad” is taking fewer cases! But don’t pop the champagne just yet.
The Kill Rate Remains Brutal
If the PTAB does institute your trial, they are coming for blood.
Recent data from late 2025 and early 2026 shows that when the PTAB issues a Final Written Decision, they cancel an astonishing 76.5% of all instituted claims. In nearly 60% of those decisions, every single instituted claim was wiped off the face of the earth. Less than a quarter of instituted claims survived the ordeal unscathed.
In short: The bouncer at the door of the PTAB has gotten incredibly strict about who they let into the club. But once you’re inside, the mortality rate hasn’t changed a bit.
The Cynical Bottom Line
The modern patent litigation ecosystem operates on a simple, ruthless premise: grant the patent easily, but make it wildly expensive to defend.
For challengers, the PTAB remains the ultimate weapon of mass destruction. Sure, you might have to file your petition early and pray you don’t get slapped with a discretionary denial, but spending $400,000 at the PTAB to completely vaporize a plaintiff’s patent is infinitely better than spending $5 million in federal court arguing in front of a jury that thinks “Java” is just a type of coffee.
For patent owners, your beautiful, gold-sealed certificate from the USPTO is ultimately just an invitation to a high-stakes knife fight in Alexandria. May the odds—and the Administrative Patent Judges—be ever in your favor.
Disclaimer: The information provided in this article is for educational and informational purposes only and does not constitute legal advice. As a professional in the field of patent law, I provide these insights as a general guide to USPTO and international procedures. I am not a registered patent attorney. Patent laws, assignment formalities, and international treaties are highly complex and continuously evolving; always consult with a qualified, registered patent practitioner to evaluate the specific ownership circumstances of your intellectual property.