By Andy Yang, Esq., Patent Attorney — The Law Office of Andy Yang
Understanding Post-Grant Patent Challenges
Many inventors assume that once the U.S. Patent and Trademark Office (USPTO) grants a patent, the rights are secure.
In reality, a granted patent can still be attacked and even overturned.
Two separate forums can review patent validity after issuance: the Patent Trial and Appeal Board (PTAB) and the federal district courts.
These dual tracks—administrative review and judicial litigation—often move forward at the same time.
When they reach opposite results, the question becomes: Who really has the final say?
1. The Two Tracks of Post-Grant Review
Administrative Review at the PTAB (USPTO)
The PTAB is an expert administrative body inside the USPTO that handles post-grant validity challenges such as Inter Partes Review (IPR) and Post-Grant Review (PGR).
Key features include:
- Technically trained judges: Most Administrative Patent Judges are scientists, engineers, or former patent examiners—many hold advanced degrees.
- Focused scope: PTAB proceedings analyze prior-art and enablement issues using a preponderance of the evidence standard.
- Predictable timeline: Most reviews finish within 12–18 months.
- Direct appeal: Decisions go straight to the U.S. Court of Appeals for the Federal Circuit, a specialized appellate court dedicated to patent law.
Because the PTAB combines technical expertise with procedural efficiency, many companies view it as the most credible forum for assessing patent validity.
Judicial Review in District Courts
District courts are part of the Article III judicial branch and hear infringement lawsuits and declaratory-judgment actions.
When a defendant claims that a patent is invalid, the court can rule on validity using a clear-and-convincing-evidence standard—higher than the PTAB’s.
However, district courts face structural limits:
- Judges are generalists, not scientists.
- Juries and law clerks usually lack technical backgrounds.
- Each court manages its own docket without specialized patent panels.
- Complex technology must be explained through expert testimony, Markman claim-construction hearings, and lengthy discovery.
These differences mean that two institutions may evaluate the same patent under different evidentiary standards, schedules, and levels of technical expertise.
2. When the PTAB and the Courts Reach Different Results
Parallel proceedings can—and often do—produce conflicting outcomes.
The controlling decision depends not on which forum is “right,” but on which decision becomes final first.
(a) If the District Court’s Judgment Becomes Final First
Once a district court’s invalidity judgment is final—after appeals or the time to appeal has expired—it binds the patent owner and effectively extinguishes the patent rights.
Even if the PTAB previously upheld the same claims, the court’s judgment overrides it in practice because Article III courts hold ultimate judicial authority.
The USPTO usually follows by marking the patent invalid in its public records.
Example:
In Fresenius USA, Inc. v. Baxter Int’l, Inc., 721 F.3d 1330 (Fed. Cir. 2013), the Federal Circuit held that if the administrative cancellation occurred before the district-court judgment was final, the PTAB (then the Board of Reexaminations) controlled.
Conversely, when a court’s judgment becomes final first, its invalidation stands despite earlier administrative validation.
(b) If the PTAB Cancels Claims After a Court Decision but Before Judgment Is Final
Timing can also favor the PTAB.
If the PTAB issues a final cancellation before the district court’s decision becomes final, the PTAB’s ruling moots the litigation—even overturning a jury verdict or damages award.
That was the precise outcome in Fresenius: once the USPTO cancellation became final, the patent claims ceased to exist and the damages judgment vanished.
(c) If Both Decisions Are on Appeal
When both tracks reach the Federal Circuit on appeal, the court can consolidate the cases or coordinate their resolution.
The Federal Circuit often gives deference to the administrative record because PTAB decisions are developed through a specialized, technical process.
3. The Practical Rule: “First Final Wins”
| Scenario | Controlling Decision | Effect |
| PTAB cancels claims before court judgment is final | PTAB controls → patent cancelled | Litigation becomes moot |
| Court invalidates patent before PTAB decision is final | Court controls → patent invalidated | USPTO updates record accordingly |
| PTAB upholds patent, but court later invalidates it and judgment becomes final | Court controls once judgment is final | Patent effectively dead |
Because each forum operates independently, timing determines control.
For companies defending their intellectual property, this means litigation strategy and procedural coordination are critical.
4. Coordinating Strategy Between the PTAB and the Courts
A smart patent-defense or enforcement plan accounts for both systems.
For patent owners:
- Consider requesting a stay of district-court litigation while PTAB review is pending.
- Monitor the appeal schedules in both forums so favorable rulings become final first.
- Ensure claim amendments or substitute claims at the PTAB align with infringement positions in court.
For challengers:
- File PTAB petitions early to create procedural leverage.
- Emphasize efficiency and technical expertise when requesting a litigation stay.
- Use consistent expert declarations across both tracks to maintain credibility.
When coordinated properly, dual-track management can reduce costs, narrow issues, and prevent conflicting outcomes.
5. Why This Dual System Exists
Congress created the PTAB through the America Invents Act (AIA) to offer a faster, technically focused alternative to litigation.
Yet the Patent Act (35 U.S.C. § 282) still allows courts to hear invalidity defenses.
As a result, patent owners can face two simultaneous reviews applying different burdens of proof.
While this overlap sometimes causes friction, it also gives businesses multiple options to defend or challenge patents.
The key is understanding which forum offers the better strategic advantage for your specific technology and case posture.
6. Key Takeaways for Patent Owners and Challengers
- Both the PTAB and district courts can decide patent validity, but they apply different rules and standards.
- Conflicting outcomes are possible; the first final decision controls.
- PTAB judges have deep technical experience, while district-court judges are generalists assisted by experts and juries.
- Timing, coordination, and forum selection can make or break a patent-enforcement strategy.
Need Guidance on PTAB and Court Strategy?
At The Law Office of Andy Yang, we help inventors, startups, and technology companies protect their patents across both forums—before the PTAB and in federal court.
If your patent is being challenged or you’re evaluating a defense strategy, contact us to discuss how to align your PTAB and litigation positions for the strongest result.
Next in the Series:
👉 Why Many Patent Attorneys Believe District Courts Shouldn’t Invalidate Patents