The parties and the patents
The proceedings are AEM Americas, Inc. v. Advantest Test Solutions, Inc., IPR2027-00005 (U.S. Patent 12,320,841) and IPR2027-00006 (U.S. Patent 11,674,999). AEM Americas, Inc. is the petitioner, and both petitions name nine real parties in interest, including AEM Holdings Ltd. and AEM Singapore Pte. Ltd. Advantest's mandatory notices, filed October 26, 2026, identify Advantest America, Inc. and Advantest Corporation as additional real parties in interest.
What the claims cover
The '999 patent issued June 13, 2023 from an application filed April 20, 2022, a continuation of the application that issued as the '841 patent on June 3, 2025. Both claim priority to a provisional application filed November 19, 2020. Claim 1 of the '841 patent covers a test system for testing circuits of an integrated circuit semiconductor wafer, including a test computer, a wafer probe contacting a first surface of the wafer, a wafer thermal interposer layer that contacts a second surface and uses resistive traces to selectively heat zones corresponding to areas of the wafer, a cold plate, and a thermal controller that maintains the temperatures of those areas by controlling the cold plate's cooling and the traces' heating. Claim 1 of the '999 patent covers a related system with a tester system; a test stack that includes a wafer probe, a wafer thermal interposer layer, and a cold plate; a thermal controller; and a pin lift mechanism whose pins pass through aligned holes in the cold plate and the interposer layer to lift the wafer.
The grounds
IPR2027-00005 challenges claims 1 to 27 of the '841 patent, and IPR2027-00006 challenges claims 1 to 25 of the '999 patent, on the same three grounds under 35 U.S.C. 103: DiBattista (U.S. Patent 6,549,026) in view of Herchen-1, Herchen-2, Pease, and Natsuhara; DiBattista in view of Costello, Herchen-1, and Criminale; and Sugiyama in view of Parkhe, Natsuhara, Criminale, and the knowledge of a person of ordinary skill in the art. Each petition is supported by the declarations of two technical experts.
The San Diego infringement case
Both petitions identify Advantest Test Solutions, Inc. v. AEM Holdings Ltd., No. 3:25-cv-02604 (S.D. Cal.), as a related matter. Advantest filed that case on October 1, 2025 against AEM Holdings Ltd., AEM Singapore Pte. Ltd., and AEM Americas, Inc., asserting the '999 and '841 patents, and the docket shows it assigned to District Judge James E. Simmons, Jr. The complaint alleges that AEM copied Advantest's wafer active thermal interposer technology with the help of a former Advantest executive, and it seeks damages, enhanced damages for any infringement found willful, and an injunction.
On June 29, 2026, Judge Simmons granted the defendants' motion to dismiss with leave to amend. The court held that the complaint did not allege non-conclusory facts showing infringing acts in the United States, as 35 U.S.C. 271(a) requires, and that the induced and contributory infringement claims failed without an underlying act of direct infringement. Advantest filed an amended complaint on July 20, 2026, the defendants moved to dismiss it on August 3, 2026, and a September 22, 2026 docket entry submitted that motion for decision.
What to watch next
In notices dated October 13, 2026, the Board accorded both petitions a filing date of October 4, 2026. Under 37 CFR 42.107(b), Advantest may file a preliminary response within three months of those notices. Under the USPTO's interim Director discretionary process, any discretionary denial brief from Advantest is due within two months of them. Watch for those filings, the institution decisions, and a ruling on the pending motion to dismiss in San Diego.