Introduction
For years, Inter Partes Review was the go-to weapon for companies facing a patent threat. File a petition, challenge the claims at PTAB, and — if the prior art was strong — get the patent invalidated or narrowed at a fraction of the cost of district court litigation. It was fast, relatively affordable, and it worked.
That playbook has changed. In early 2026, PTAB is denying over 63% of IPR petitions. Director Squires’ centralized institution process has made discretionary denial the norm, not the exception. Patents that are six or more years old are increasingly shielded under the ‘settled expectations’ doctrine. Ex parte reexamination filings are up 66% in 2025 as challengers scramble for alternatives.
Here’s what that means for your team: the first line of defense is no longer the IPR petition. It’s the patent invalidation search that feeds every path you have — IPR when it’s viable, ex parte reexam when it isn’t, and district court invalidity when neither works. How thoroughly that search is executed determines whether you fight from a position of strength or scramble with weak prior art when it matters most.
Why the PTAB Shift Makes Pre-Litigation Invalidity Search More Critical Than Ever
Let’s be direct about what’s happening at the PTAB. Under Director Squires, institution decisions are now centralized — meaning the Director’s office reviews petitions before the Board does. The result has been a surge in summary denials. If you want a deeper breakdown of how IPR and PGR strategies have shifted under the new PTAB regime, the landscape has changed significantly even from 18 months ago.
Three factors are driving denials right now:
- The ‘settled expectations’ doctrine. Patents that have been in force for six or more years are increasingly getting discretionary denials. The logic: patent owners and licensees have built businesses around these patents, and PTAB is giving more weight to that reliance. If the patent you’re targeting is older, IPR may simply not be available to you.
- Fintiv factors still apply. Parallel district court litigation can get your IPR petition denied under the Fintiv framework, even with strong prior art. If the district court case is moving fast, PTAB may decline to institute on efficiency grounds.
- The bar for ‘reasonable likelihood’ has risen. On paper, IPR institution requires showing a reasonable likelihood that at least one claim is unpatentable. In practice, the Director’s review has pushed the effective bar significantly higher.
The consequence is straightforward: district court invalidity defense and ex parte reexamination are now carrying a load they haven’t carried since before the America Invents Act. Both depend entirely on the quality of your prior art case. A weak invalidation search at the start means weaker leverage at every stage.
What a Rigorous Patent Invalidation Search Actually Covers
Most invalidity searches that fall short in litigation or PTAB proceedings share a common problem: they were scoped too narrowly, executed too quickly, or relied on a single database. Here’s what a thorough search actually looks like.
- Claim construction first. You can’t find the right prior art until you know exactly what the claims cover. Every independent claim gets parsed element by element — not a summary reading, but a careful construction that maps each limitation to what the patentee actually argued during prosecution. Skip this step and you’ll find art that looks relevant but doesn’t map to the claims the way a court or the PTAB will read them.
- Multi-database patent search. USPTO alone isn’t enough. A rigorous search covers USPTO, Espacenet, WIPO PATENTSCOPE, JPO (Japan), and KIPO (Korea) using both CPC/IPC classification-based search and keyword-plus-semantic search. The best prior art for any given patent is often sitting in a Japanese or Korean database that a keyword-only US search would never surface.
- Non-patent literature (NPL). This is where most searches fall short — and where some of the best prior art hides. Academic papers, conference proceedings, technical standards documents, product manuals, and public disclosures all count as prior art. In software, AI, and semiconductor cases, the paper that anticipates the claim is frequently a conference proceeding from a decade ago, not a patent.
- Foreign language prior art. Japanese, German, Korean, and Chinese language documents are routinely overlooked. That’s a problem, because foreign filings — especially Japanese and Korean — frequently predate US patents in fast-moving technology sectors and contain the most technically detailed prior art available.
- Prosecution history review. The file wrapper tells you what the patentee argued to get the claims granted. Those arguments define the boundaries of the claims — and they often reveal the exact distinctions over prior art that were made during prosecution. Understanding the prosecution history before you search means you know precisely what your prior art needs to show.
The Three Scenarios Where a Patent Invalidation Search Wins Before Trial
A strong invalidity position doesn’t just matter at trial. In most cases, it matters long before you get there.
- Licensing negotiation. If you’ve identified prior art that would materially threaten the patent’s validity, the licensor knows it too — once you show them. A well-documented invalidity position changes the negotiating dynamic entirely. Instead of being pressured into a royalty based on the patent’s stated value, you’re negotiating with a credible alternative in hand: invalidate the patent, or accept a rate that reflects its actual risk profile.
- Demand letter response. A significant proportion of patent assertion campaigns end at the demand letter stage when the target responds with a strong invalidity analysis. Assertion entities — particularly those running volume campaigns — move on when the path to settlement becomes expensive. A well-executed prior art search delivered promptly after a demand letter is one of the most cost-effective tools in patent defense.
- Pre-trial motion practice. For cases that do proceed to district court, a robust prior art record built before claim construction gives your counsel the ammunition for summary judgment on invalidity. It also supports your invalidity expert’s report at trial. The search that was done early, thoroughly, and to a court-ready standard is the one that actually moves the needle.
“The invalidity search isn’t just preparation for PTAB or trial. It’s the document that determines your leverage at every stage — from the first licensing conversation to the last day of trial. The earlier it’s done well, the more options you have.”
Where Most Patent Invalidation Searches Fall Short
Knowing what a good search looks like is only half the picture. Here’s where searches typically break down — and why it matters when the stakes are high.
- Keyword-only searches. Searching patent databases with product terminology instead of claim language misses the art a skilled examiner would have found. Patents use classification codes, not product names. A keyword-only search gives you art that matches your vocabulary, not art that maps to the claims.
- Stopping at the USPTO. The best invalidating reference for a US patent is often sitting in the JPO or KIPO database. If your search stops at the US border, you’re leaving some of the most powerful prior art on the table.
- Skipping NPL entirely. Standards documents, academic papers, and conference proceedings regularly anticipate claims — especially in software, AI, and wireless technology. A search without NPL coverage has a structural blind spot that experienced patent assertion counsel will exploit.
- Finding art but not charting it. A reference that’s found but not mapped to specific claim elements is nearly useless in litigation. Every relevant reference needs a claim chart that shows element-by-element how the art anticipates or renders obvious each limitation. That’s what counsel and courts actually work from.
- Missing continuation chains. The asserted patent may have siblings — continuations, divisionals, or continuation-in-part applications — with overlapping or broader claims. If your search doesn’t cover the full family, you may be invalidating the wrong claims while the commercially important ones remain standing.
How TT Consultants Conducts Patent Invalidation Searches
TT Consultants patent invalidation search service is built for exactly the environment described above — where IPR isn’t always available and the invalidity position has to hold up in district court or ex parte reexamination.
Every engagement starts with claim construction — parsing each independent claim before a single database is searched. The search covers USPTO, Espacenet, JPO, KIPO, and WIPO PATENTSCOPE using CPC and IPC classification-based search, keyword-plus-semantic methods, and dedicated NPL search across academic databases, conference proceedings, and technical standards. Foreign language documents — Japanese, Korean, German — are reviewed directly, not via machine translation only.
The output is a court-ready invalidity report: element-by-element claim charts for every relevant reference, prosecution history analysis showing what the patentee argued to get the claims granted, and a clear mapping of which references anticipate under § 102 vs. render obvious under § 103. For more on how invalidation search strategies feed into IPR, reexamination, and district court proceedings, TTC’s approach covers all three paths from a single search engagement.
With IPR harder to get than ever, your invalidity search needs to be litigation-grade from day one. TT Consultants delivers prior art searches that give you real leverage — wherever the case goes. → Contact Us
Conclusion: The Takeaway
The PTAB isn’t the reliable institution path it used to be. That’s not a temporary fluctuation — it’s the current reality under Director Squires’ leadership, and it’s reshaping how companies approach patent defense from day one.
The shift puts more weight on the patent invalidation search than ever before. When IPR is denied, the prior art case has to work in district court or ex parte reexamination. When it’s not denied, the petition still lives or dies on the quality of the references submitted. Either way, the search is the foundation.
The companies that invest in a rigorous, multi-database, NPL-inclusive, claim-charted invalidity search at the start have more options at every stage — in negotiations, before the PTAB, and in court. The ones that don’t are starting every dispute from behind.
