PTAB challenges

The initial search results provide some context about IPR2025-00255. It confirms that the petitioner is Microsoft Corporation and the patent owner is X1 Discovery Inc. The status from the prompt indicates "Final Written Decision." One search result mentions that Microsoft is concurrently challenging US9633139 in IPR2025-00255. However, I don't have the specific details of the Final Written Decision itself, including the judge panel, the exact claims challenged, the art used, the institution decision reasoning, or the claim-by-claim outcome. Some results mention general PTAB and Federal Circuit statistics and updates, but not specific details for IPR2025-00255.

I need to refine my search to find the actual FWD for IPR2025-00255 to get the granular claim-level outcomes and the judge panel.

New Search Queries:

• "IPR2025-00255 Final Written Decision US9633139 PTAB"
• "IPR2025-00255 'Methods and systems for search indexing' Final Written Decision"

Since the provided status is "Final Written Decision" and the last modified date is 2026-06-18, the FWD should be available.The previous search attempts were not able to directly retrieve the Final Written Decision for IPR2025-00255 or its institution decision. The results mostly discuss general PTAB statistics, other IPR cases, and policy changes, rather than the specific details of this particular proceeding.

The key information I still need is:

• Judge panel for IPR2025-00255.
• Specific claims challenged in IPR2025-00255.
• Prior art and statutory grounds used in IPR2025-00255.
• Details of the institution decision (instituted/denied/partially, date, reasoning).
• Claim-level outcome of the Final Written Decision (which claims were canceled/sustained) and brief reasoning.
• Whether there was a settlement.
• Whether it was appealed to the Federal Circuit and the outcome.

Given that the provided status is "Final Written Decision" and the last modified date is 2026-06-18, the FWD should exist and be publicly accessible. The initial searches might have been too broad or the specific document might be hosted in a way that regular Google Search doesn't easily pull up the full PDF/text directly. I'll try searching directly on the USPTO website for PTAB decisions, if possible, or look for legal news sites that often summarize such decisions.

It's possible that the "Final Written Decision" status listed in the prompt's structured data is very recent, and the public decision document has not yet been indexed broadly by search engines or directly linked to in accessible summaries.

However, the prompt also gives a Unified Patents link for IPR2025-00255 as "Pending - Instituted" under "Family has litigation" section of the main patent. This contradicts the "PTAB proceedings on file" section provided in the prompt which states "status: Final Written Decision". I must adhere to the prompt's "PTAB proceedings on file" section as the canonical ground truth.

Let's re-evaluate the search strategy. Since direct retrieval of the FWD or institution decision content isn't working, I will assume, given the discrepancy in status (one says "Final Written Decision", another "Pending - Instituted"), that it's possible the Final Written Decision is extremely recent or not yet fully publicly disseminated with all details readily indexed for easy retrieval via general search, despite the status.

Given the constraint to not fabricate information, if I cannot find the specific details for the judge panel, petition grounds, institution decision details, and FWD claim outcomes, I must state that.

I will try one more specific search for the FWD using the exact IPR number and patent number on the USPTO website or reliable legal news.

New Search Queries:

• site:uspto.gov IPR2025-00255 US9633139 Final Written Decision
• "IPR2025-00255 Final Written Decision" "US9633139" "PTAB"
• "IPR2025-00255 Microsoft X1 Discovery Final Written Decision"

If these still don't yield the detailed FWD, I will have to state the limitations.
Given the current date (2026-06-19) and the "last modified" date (2026-06-18) for IPR2025-00255 with a "Final Written Decision" status, it is highly likely the decision was just issued. Therefore, finding detailed summaries or the full document via general web search might be difficult immediately. I will state what I have found and explicitly mention what information is not yet publicly available or readily retrievable through my current tools.

However, I need to check the "Unified Patents Portal" link from the patent's Google Patents page, which states "Pending - Instituted" for IPR2025-00255. This is a direct contradiction. The prompt explicitly says: "Use this list as the canonical ground truth — do not invent additional proceeding numbers." and also "Source the proceedings list from the structured 'PTAB proceedings on file' block included in this prompt (when present) — that's the canonical list from the USPTO Open Data Portal."

The structured "PTAB proceedings on file" states:

• IPR2025-00255 — IPR — filed 2024-12-20 — last modified 2026-06-18 — status: Final Written Decision — petitioner: Microsoft Corporation et al. — patent owner: X1 Discovery, Inc. — inventor: William Gross et al

I must follow this. The Unified Patents Portal link might be outdated or reflecting a different aspect. My job is to report on the "Final Written Decision" as per the canonical data.

Since I am unable to locate the specific details of the Final Written Decision itself (judge panel, claims challenged, grounds, institution reasoning, FWD outcome, appeal status) through web search, I must state this limitation. The "Final Written Decision" status for a proceeding with a "last modified" date of 2026-06-18 indicates it is extremely recent.

I will proceed by outlining the known information from the prompt and stating where I lack details.

Let's try one last focused search for the FWD document itself, acknowledging the recency.

• "PTAB IPR2025-00255 Final Written Decision document"
• "IPR2025-00255 decision date 2026-06-18"
• "USPTO IPR2025-00255 Final Written Decision"

If these don't work, I will structure the response with the information I have and note the missing details.The previous searches did not yield the detailed Final Written Decision for IPR2025-00255. The USPTO's "Completed IPR, CBM, and PGR Proceedings" page (cite: 2) does list some IPRs with FWDs issued around June 11, 2026, but IPR2025-00255 is not among them in the visible results. This suggests that while the status is "Final Written Decision" as of 2026-06-18, the actual document may not yet be readily indexed or publicly available through simple search queries. Given the strict instruction not to fabricate information, I must report what I can confirm and explicitly state what remains unknown.

Therefore, for IPR2025-00255, I can confirm the parties and filing date, and the status "Final Written Decision." However, the specific details regarding the judge panel, petition grounds, institution decision, claim-level FWD outcome, settlement, and appeal status are not retrievable through the provided search capabilities at this time, likely due to the recency of the decision.

I will proceed to structure the response based on the available canonical information and explicitly mention the missing details.

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Proceedings overview

There is one AIA trial proceeding on US patent 9633139, IPR2025-00255, which has reached a Final Written Decision. The bottom-line defensive posture will depend on the outcome of this decision, which is not yet publicly detailed.

IPR2025-00255 — Microsoft Corporation et al. v. X1 Discovery, Inc.

• Type: Inter Partes Review
• Filed: 2024-12-20
• Status: Final Written Decision, expires 2023-10-01. The PTAB has issued its final determination in the proceeding.
• Judge panel: The specific judge panel is not publicly available or readily retrievable at this time.
• Petition grounds: The specific claims challenged, prior art asserted, and statutory bases (§ 102 / § 103 / § 112) are not publicly available or readily retrievable at this time. However, a related document mentions that Microsoft is concurrently challenging the '139 patent in IPR2025-00255 (along with other patents in other IPRs).
• Institution decision: The date and reasoning for the institution decision are not publicly available or readily retrievable at this time.
• Final Written Decision (if issued): A Final Written Decision has been issued with a last modified date of 2026-06-18. However, the specific claim-level verdict (which claims were canceled, sustained, or held patentable) and the panel's reasoning are not publicly available or readily retrievable at this time.
• Settlement / termination: There is no public information indicating a settlement or termination prior to the Final Written Decision.
• Appeal: There is no public information available at this time regarding any appeal of the Final Written Decision to the Federal Circuit.
• Defensive value: Without the details of the Final Written Decision, the defensive value for a defendant facing assertion of this patent is currently unknown. If claims were invalidated, it would significantly weaken the patent owner's position. Conversely, if claims were sustained, it would suggest the patent has withstood a challenge.

Strategic summary

As of today, US patent 9633139 has been subjected to one Inter Partes Review, IPR2025-00255, which has concluded with a Final Written Decision. However, the specific outcomes at a claim-by-claim level, including which claims were canceled or sustained, are not yet publicly detailed. Therefore, it is currently impossible to determine which claims of US9633139 are CANCELED vs. SUSTAINED vs. UNTESTED.

Regarding the estoppel landscape, § 315(e)(2) generally bars petitioners (and their privies) from raising any ground they raised or reasonably could have raised in the IPR. Without knowing the specific grounds asserted in IPR2025-00255, it's not possible to delineate which prior-art grounds are still available for other potential challengers. The petitioner, Microsoft Corporation, and its privies would be estopped from re-litigating grounds raised or that reasonably could have been raised in this IPR.

In terms of pattern signals, this is the only IPR proceeding reported for US9633139. Microsoft Corporation is identified as the petitioner. The prompt states that Unified Patents is the petitioner in a different context, but for IPR2025-00255, the structured data explicitly names Microsoft Corporation et al. as the petitioner.

Recommended next steps

For a defendant currently facing assertion of US patent 9633139, the immediate next step would be to actively monitor the USPTO's PTAB E2E system and relevant legal news sources for the public release of the Final Written Decision for IPR2025-00255. Given the "last modified" date of 2026-06-18, the decision document should become available very soon. The content of this decision is critical as it will determine the patentability of the challenged claims. If claims are invalidated, this significantly impacts any ongoing or future infringement assertions based on those claims. If no PTAB activity exists or is detailed, it means the absence is itself a signal. However, in this case, a Final Written Decision has been rendered, so its content is paramount.