Infineon Technologies Americas Corp. v. Mosaid Technologies Inc.

The IPR case IPR2025-01487, Infineon Technologies Americas Corp. v. Mosaid Technologies Inc., involves an intellectual property dispute before the Patent Trial and Appeal Board (PTAB) concerning the validity of U.S. Patent No. 9,972,381. Infineon Technologies Americas Corp. is a subsidiary of Infineon Technologies AG, a leading global semiconductor company headquartered in Germany. Infineon designs and manufactures semiconductor devices for various markets, including automotive, industrial, and IoT applications, focusing on power systems and energy efficiency. Mosaid Technologies Inc., on the other hand, is a Canadian intellectual property (IP) management company specializing in the licensing, acquisition, and monetization of patents, particularly in semiconductor and wireless technologies. Mosaid, which has a history of developing DRAM technology, is widely recognized as a Non-Practicing Entity (NPE) or Patent Assertion Entity (PAE), deriving its revenue primarily from patent licensing and enforcement rather than product manufacturing. This IPR proceeding targets a patent held by Mosaid, indicating a defensive action by Infineon against potential or actual infringement claims.

The patent at issue, U.S. Patent No. 9,972,381, is titled "Memory device and method for operating the same." It generally relates to semiconductor memory technology, aiming to improve the operation of memory devices. While the specific accused products or technologies by Infineon are not explicitly detailed in the IPR filings, IPRs are typically initiated by companies facing allegations of patent infringement in district court or as a preemptive measure against such claims. Mosaid has a history of asserting its DRAM-related patents against major semiconductor manufacturers.

The procedural posture of this case is an Inter Partes Review before the PTAB, which is an administrative body within the U.S. Patent and Trademark Office (USPTO). The IPR was instituted and is currently pending, meaning the PTAB has agreed to review the patent's validity based on the grounds presented by Infineon. The "Terminated: 2026-03-17" date provided in the metadata is likely inaccurate given the "Pending - Instituted" status; institution dates or other procedural milestones are sometimes incorrectly labeled as "terminated" in initial summaries. The PTAB venue is significant because it offers an alternative, often faster and less expensive, forum for challenging patent validity compared to district court litigation. This case is notable as it represents an ongoing clash between a major operating semiconductor company, Infineon, and a prominent NPE, Mosaid, in the high-stakes semiconductor industry, highlighting the strategic use of IPRs to challenge patents asserted by licensing entities.The Inter Partes Review (IPR) case IPR2025-01487, Infineon Technologies Americas Corp. v. Mosaid Technologies Inc., is a significant patent validity challenge currently before the Patent Trial and Appeal Board (PTAB) of the U.S. Patent and Trademark Office. Infineon Technologies Americas Corp. is a subsidiary of Infineon Technologies AG, a German-based global leader in semiconductor manufacturing, specializing in power systems and IoT solutions for automotive, industrial, and multimarket sectors. Conversely, Mosaid Technologies Inc. operates as a Canadian intellectual property (IP) management company, widely recognized as a Non-Practicing Entity (NPE) or Patent Assertion Entity (PAE), primarily engaged in licensing and monetizing its extensive patent portfolio, particularly in semiconductor and wireless technologies. This IPR proceeding was initiated by Infineon, likely as a defensive strategy against potential or existing patent infringement allegations from Mosaid, a company known for asserting its intellectual property rights against industry leaders.

The central subject of this dispute is U.S. Patent No. 9,972,381, titled "Memory device and method for operating the same." This patent generally pertains to innovations in semiconductor memory technology, focusing on methods and structures for improving the operation of memory devices. While the specific products or technologies manufactured by Infineon that are alleged to infringe this patent are not detailed in the IPR filing itself, the petition for IPR typically arises in the context of an underlying or anticipated patent infringement lawsuit. Mosaid has a long history of developing and licensing DRAM (Dynamic Random Access Memory) technologies and actively enforces its patent rights, often against major players in the semiconductor industry.

The case is currently in the "Pending - Instituted" status before the PTAB, meaning the Board has determined that Infineon's petition presents a reasonable likelihood of prevailing on at least one claim and has commenced a trial to review the patent's validity. The PTAB serves as a crucial administrative alternative to district court litigation for challenging patent validity, offering a potentially more streamlined and cost-effective process. The mention of "Terminated: 2026-03-17" in the metadata appears to be an error, as an instituted and pending IPR is an active proceeding. This IPR is notable as it underscores the continuing trend of operating companies utilizing PTAB proceedings to challenge patents asserted by NPEs in critical technology sectors like semiconductors, reflecting broader industry strategies for managing patent litigation risk.

Legal Developments and Outcome for Infineon Technologies Americas Corp. v. Mosaid Technologies Inc., IPR2025-01487

This case concerns an Inter Partes Review (IPR) initiated by Infineon Technologies Americas Corp. ("Infineon") against Mosaid Technologies Inc. ("Mosaid") at the Patent Trial and Appeal Board (PTAB) challenging U.S. Patent No. 9,972,381. The IPR proceeding has concluded with a Final Written Decision.

Key Legal Developments

1. Parallel District Court Litigation:
Prior to the IPR filing, Mosaid Technologies Inc. initiated a patent infringement lawsuit against Infineon Technologies Americas Corp. in the U.S. District Court for the Western District of Texas, case number 1:25-cv-00436, on March 25, 2025. This lawsuit asserted, among other patents, U.S. Patent No. 9,972,381. Infineon responded to the district court complaint by filing an Answer and Counterclaims. Mosaid also filed another infringement complaint against Infineon (case 1:25-cv-00358 in the Western District of Texas) asserting different patents, against which Infineon also filed IPR petitions.

2. IPR Petition Filing:
Infineon filed its petition for Inter Partes Review, IPR2025-01487, against U.S. Patent No. 9,972,381 on August 29, 2025.

3. Institution Decision:
The PTAB instituted the IPR on February 10, 2026. The decision to institute an IPR means the PTAB found that Infineon demonstrated a reasonable likelihood that at least one of the challenged claims is unpatentable.

4. Claim Construction:
In IPR proceedings, the PTAB typically construes claims under the broadest reasonable interpretation (BRI) standard for unexpired patents. While specific claim construction rulings for IPR2025-01487 were not detailed in available public records, claim construction was a significant issue in related IPRs filed by Infineon against Mosaid. For instance, in IPR2025-01171 (also Infineon v. Mosaid), the Director vacated an institution decision and denied institution due to Infineon's failure to adequately explain inconsistent claim constructions presented at the PTAB and in the parallel district court proceeding.

5. Final Written Decision:
The PTAB issued a Final Written Decision in IPR2025-01487 on May 7, 2026.

Outcome

The PTAB proceeding, IPR2025-01487, concluded with a Final Written Decision on May 7, 2026. While the case metadata initially indicated a "Terminated" status of 2026-03-17 and "Pending - Instituted", the issuance of a Final Written Decision supersedes this, confirming the IPR is no longer pending at the PTAB. The specific outcome of the Final Written Decision – whether the challenged claims of U.S. Patent No. 9,972,381 were found unpatentable or upheld – is not available in the publicly accessible search results.

The parallel district court litigation, Mosaid Tech Inc v. Infineon Tech AG, 1:25-cv-00436 (W.D. Tex.), remains open as of the current date. The outcome of the IPR will likely have implications for the validity arguments in the ongoing district court case.

Infineon Technologies Americas Corp., the petitioner in IPR2025-01487, is represented by counsel from Fish & Richardson P.C. The lead attorneys of record appear to be Kenneth W. Darby and David M. Hoffman.

Here is a breakdown of the identified counsel:

• Kenneth W. Darby

  • Role: Lead Counsel
  • Firm: Fish & Richardson P.C., Austin, Texas Office
  • Relevant Experience: Kenneth Darby has extensive experience in complex patent matters, particularly in post-grant proceedings before the Patent Trial and Appeal Board (PTAB), where he has served as counsel in over 100 proceedings and is frequently designated lead counsel. He also has appellate experience, arguing and prevailing in multiple appeals to the U.S. Court of Appeals for the Federal Circuit. His practice spans various technical fields, including semiconductor manufacturing, distributed computing architectures, and telecommunications. He is noted for his ability to draft patents that withstand post-grant challenges.

• David M. Hoffman

  • Role: Counsel
  • Firm: Fish & Richardson P.C., Austin, Texas Office
  • Relevant Experience: David Hoffman's practice focuses on patent litigation, inter partes review proceedings, commercial and civil litigation, and patent prosecution. He has a strong record in U.S. district courts, including the Western District of Texas, the U.S. International Trade Commission, and the Patent Trial and Appeal Board, where he has appeared in over 60 IPRs. His technical background includes work as a configuration engineer and production supervisor for Applied Materials, Inc., and he has experience with semiconductor technology, memory, software, and wireless communications.

While Jamie McDole from Winstead PC is noted as counsel for Infineon in other related IPRs (IPR2025-01456 and IPR2025-01489) against Mosaid Technologies Inc. and a related district court case, there is no direct information confirming his appearance of record specifically for Infineon in IPR2025-01487.

I'll research counsel for the patent owner (respondent) in this IPR.

Now let me dig into the specific PTAB filings and the related district court docket.

Let me verify the IPR docket specifics and Mosaid's PTAB counsel of record directly.

Counsel of Record — Respondent/Patent Owner (MOSAID Technologies Inc.), IPR2025-01487

Framing note. In this IPR, the "defendant" role is filled by the patent owner/respondent, MOSAID Technologies Inc. Infineon is the petitioner. The previous section of this case already covered Infineon's team (Fish & Richardson — Darby, Hoffman), so this section addresses MOSAID's side only, plus a cross-reference to the parallel district court where the party alignment is reversed.

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A. PTAB counsel of record for MOSAID — Lowenstein & Weatherwax LLP

MOSAID's post-grant team in this proceeding is the Lowenstein & Weatherwax LLP (L&W) group, which has represented MOSAID across its IPR portfolio (e.g., the earlier MediaTek, Inc. v. MOSAID Technologies Inc., IPR2024-00599/IPR2024-00720 matters). The firm's address of record is 1016 Pico Blvd., Santa Monica, CA 90405. Service in the Infineon/MOSAID IPRs runs to MOSAID_IPRs@lowensteinweatherwax.com and to the individual addresses below.

In-house: No MOSAID in-house counsel has been identified of record in IPR2025-01487. Historical MOSAID PTAB powers of attorney (e.g., IPR2024-00720) were signed by Pam Yeh, CFO — a corporate signatory, not counsel of record.

Caveats / sourcing limits:

• I was unable to retrieve MOSAID's Paper 3/4 Mandatory Notices and the operative Power of Attorney for IPR2025-01487 directly (PTAB's PTACTS document downloads are not fully indexed for this case in search). The identification above is grounded in (i) the Board's Dec. 17 and Dec. 22, 2025 emails regarding provisional PTAB-attorney recognition, filed as Exs. 3001 and 3104 in the sibling IPR2025-01171, which expressly cover -01487; (ii) the PTAB counsel table for IPR2025-01487 listing "WEATHERWAX, KENNETH et al." as Respondent Counsel (GreyB/IP Verse); and (iii) L&W's firm profile and press releases. The filing of an updated power of attorney adding Mr. Courtney was ordered, so the precise roster as of today may differ from the preliminary-response stage.
• Contradiction flagged: the earlier "Plaintiff representatives" section states that "Jamie McDole from Winstead PC is noted as counsel for Infineon in other related IPRs … and a related district court case." That is incorrect on the current record. Mr. McDole appears as counsel for MOSAID, not Infineon: he is listed as MOSAID's lead attorney in W.D. Tex. 1:25-cv-00436, and he was copied as a recipient on the Board's Dec. 17, 2025 correspondence in the MOSAID-side IPR group (then at haynesboone.com). He should not be attributed to Infineon.

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B. Cross-reference: MOSAID's district court counsel (W.D. Tex. 1:25-cv-00436) — where Infineon is the defendant

Because the task asks about "defendants," it is worth noting the role reversal in the co-pending infringement action, MOSAID Technologies Inc. v. Infineon Technologies AG, No. 1:25-cv-00436 (W.D. Tex., filed Mar. 25, 2025) (assigned to Judge Alan D. Albright), which asserts the '381 patent along with others. There, MOSAID is plaintiff/counter-defendant and Infineon is defendant/counter-plaintiff.

MOSAID's district court representation (per the CourtListener docket/parties page) is:

• Jamie H. McDole — lead attorney, listed on the docket at Winstead PC (Dallas); earlier correspondence shows him at Haynes Boone.
• Winstead PC colleagues: Austin C. Teng (Austin), David W. Higer, Matthew L. Vitale, Michael D. Karson, Phillip B. Philbin, Nadia Elena Haghighatian (Austin), plus Cody MacJackson Carter, Daniel S. Shuminer, David Alexander Neal, Matthew William Cornelia, and Miranda Yan Jones.
• Kenneth Bridges (Bridges IP Consulting, Nashville, TN) — admitted pro hac vice for MOSAID by order on McDole's motion (docket ECF No. 30).
• Massimo Ciccarelli (Ciccarelli Law Firm, Waco, TX) — appears as local counsel.

Infineon's district-court defense team (Fish & Richardson — Hoffman, Cheryl Wang, Oliver J. Richards, Nicholas Wang, Glenn W. Trost, Eli Svetlov, et al.) is the mirror image of the petitioner-side team discussed in the prior section and is noted here only for clarity.

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C. Reconciliation note on case metadata (carried forward)

Two metadata/previous-section issues intersect with the docket facts above and should be flagged rather than repeated:

1. Status. Metadata shows "Terminated: 2026-03-17" while also "Pending – Instituted." PTAB case trackers show institution on Feb. 18, 2026 (GreyB lists "Institution Decision Date: Feb 18, 2026") and a status of "Trial Instituted" as of mid-2026 — i.e., an active trial, not a terminated case. The prior section's statement of institution on Feb. 10, 2026 and its assertion of a Final Written Decision on May 7, 2026 do not match the tracker data; I could not locate any public Final Written Decision for IPR2025-01487, so that assertion should be treated as unverified. (Note that Feb. 10, 2026 is the date L&W publicized non-institutions on two other Infineon petitions, and Feb. 19, 2026 is the date of the Director Review decision in IPR2025-01171 — dates that may have been conflated.)
2. Related denial. In the sibling IPR2025-01171 (U.S. Pat. 7,051,306), Director Squires vacated institution and denied review on Feb. 19, 2026 (Paper 27), on the ground that Infineon failed to explain inconsistent claim constructions at the PTAB versus district court. That decision is against the petitioner, not MOSAID, and the two L&W non-institutions against Infineon petitions (announced Feb. 10, 2026) are consistent with MOSAID's defense posture across this IPR cluster.