USPTO to Enforce Stricter Mapping in IPR Petitions — A Win for Patent Owners and Innovators

The U.S. Patent and Trademark Office (USPTO) recently issued a pivotal memorandum, signaling a significant change in how inter partes review (IPR) petitions must be structured. Starting September 1, 2025, petitioners will be required to explicitly specify where each element of a claim appears in the cited prior art patents or printed publications, reverting from the more flexible approach previously tolerated since IPR’s inception in 2012.

TO READ THE USPTO MEMORANDUM CLICK HERE. 

What’s Changing (and What’s Staying the Same)

Strict Enforcement of 37 C.F.R. § 42.104(b)(4)

• Petitioners can no longer rely on general knowledge—such as applicant‑admitted prior art (AAPA), expert testimony, common sense, or other non‑published evidence—to supply missing claim limitations

• Instead, every claim element must be directly matched to express disclosures in patents or printed publications.

Allowed Use of General Knowledge – but Limited

• General knowledge may still be used to support:

  • Motivation to combine references,

  • Contextual understanding,

  • Establishing what a person of ordinary skill in the art (POSITA) would know

  • Note that the memorandum cites to, “affirming general knowledge in the IPR proceeding in the form of expert testimony and applicant admitted prior art (AAPA) to demonstrate how a skilled artisan would have understood a prior art reference’s disclosure as teaching a claim limitation.”  Because of this, petitioners should have either expert testimony and/or AAPA to bolster positions supporting a motivation to combine or demonstrate knowledge of a POSITA. 

Why This Shift Matters

1. Reinforces Patent Owners’ Rights

Patent owners now gain a stronger procedural footing. If a petitioner improperly leans on general knowledge to fill evidentiary gaps, patent owners can challenge the petition on that basis—potentially leading to denials before institution. 

2. Elevates the Bar for Petitioners

With general knowledge disallowed for filling claim gaps, petitioners must conduct more rigorous prior art searches and ensure completeness of their citations. This increases both the time and precision required in drafting IPR petitions.

3. Alignment with Federal Circuit Decisions

The policy revision responds to Federal Circuit rulings—including Qualcomm v. Apple (2022 and 2025) and Shockwave Medical v. Cardiovascular Systems—that underscored the statutory requirement that IPR grounds be based solely on prior art patents or printed publications.

Implementation Timeline

• Effective Date: Applies to all IPR petitions filed on or after September 1, 2025 

• Petitioners must now explicitly map every claim element to a specific location in a prior art reference.

• Any reliance on general knowledge must be strictly for permissible purposes—not for supplying limitations

Key Takeaways

Stakeholder	Implication
Petitioners	Must conduct thorough prior art research and create detailed mappings from claim elements to prior art disclosures. General knowledge no longer fills in missing pieces.
Patent Owners	Should carefully analyze IPR petitions for improper reliance on general knowledge and use this policy to bolster defenses.
Practitioners	Need to sharpen petition strategies and preemptively address potential gaps in claim mapping.

This revision ensures clarity and fairness in IPR proceedings, obliging petitioners to build more robust, transparent, and defensible challenges.

Patent owners, in turn, gain reinforced procedural defenses to help safeguard their intellectual property.  Between the doctrine of settled expectations and the USPTO’s new guidance mandating strict element-by-element mapping, patent owners’ rights are being significantly strengthened against IPR challenges.