China's 3D NAND maker YMTC (Yangtze Memory Technologies) has won a sales injunction against Micron in Germany. According to the legal trade publication ip fray, the Munich Regional Court I (Landgericht München I) ruled on September 18, 2026, that Micron had infringed two of YMTC's German utility models. YMTC has been expanding its litigation campaign since 2023 across the United States, China, the UK, and the Unified Patent Court (UPC), but this injunction emerged from the Munich case, where a ruling came just 347 days after filing. Notably, the rights at issue were not patents but utility models (Gebrauchsmuster), which are registered without substantive examination. How far this win on the "fast track" actually extends into the broader dispute can only be judged by looking at the three postponed cases, the ongoing US trial proceedings, and how much time is left on the rights themselves.
What the Munich court ordered — and what it didn't
The ruling was issued by the 7th Civil Chamber of the Munich Regional Court I, reportedly presided over by Judge Oliver Schön. Infringement was found on two German utility models: DE202020006166U1, "Staircase structure for a three-dimensional memory device" (case number 7 O 12615/25), and DE202021004551U1, "Barrier layer for word line contacts in 3D NAND" (case number 7 O 12614/25). Both rights relate to the stacking structure and wiring of 3D NAND, and Google Patents lists Yangtze Memory Technologies Co Ltd as the owner.
TechNode and IT Home report that the injunction covers the sale of infringing products within Germany. However, no report has identified the specific Micron product models affected. The amount of security required for enforcement, and whether YMTC has begun enforcement, also remain unknown.
The remaining three cases heard the same day were postponed. These involved DE202018007011U1 (a multilayer-stack three-dimensional memory device), DE202022003278U1 (a three-dimensional memory device), and European patent EP3931868 (a three-dimensional memory device with deposited semiconductor plugs) — all of which had their hearings pushed back. Of the five cases YMTC brought, only two resulted in an injunction.
Micron responded quickly. According to IT Home and others, the company said it disagrees with the ruling, has already filed an appeal, and is contesting the validity of the rights through separate proceedings. China's Kuai Technology reported that Micron emphasized the rights in question were "German utility models that did not undergo substantive examination, not rigorously examined patents," and stated that it holds more than 62,000 patents of its own. Citing IT Home, TechNode reported that this marks YMTC's first substantive injunction win since the dispute intensified in November 2023.
Why the utility models took effect first
The difference between a patent and a utility model lies in whether an examiner reviews the substance before registration. A patent is granted only after an examiner confirms novelty and inventiveness. German utility models, by contrast, are registered without substantive examination, and their term of protection begins on the filing date and expires ten years after the end of the month in which that filing date falls.
Because the right comes into existence without waiting for examination, the holder can bring infringement suits at an early stage. In exchange, the question of whether the right is actually valid is not verified at the time of registration, leaving room for the opposing party to challenge it later. Micron's repeated emphasis that these are "not rigorously examined patents" targets exactly this structural feature.
According to ip fray, the two utility models at issue in this case were derived from patent applications — that is, content from patent applications still under examination was carved out as rights that skip the examination wait. Google Patents lists the filing dates as March 23, 2020 and December 22, 2021.
The difference in timing shows up in the numbers. According to Micron's 10-Q (quarterly report), YMTC filed the five suits with the Munich Regional Court on October 6, 2025, and the ruling came on September 18, 2026 — 347 days later. By contrast, ip fray reported in October 2025 that YMTC's first lawsuit, filed in the US District Court for the Northern District of California (N.D. Cal.) in November 2023, remains stayed pending IPR (inter partes review, a US Patent Trial and Appeal Board proceeding for challenging patent validity) proceedings. Before a ruling could be reached in the US, the German case — filed nearly two years later — produced a result first.
ip fray also points to another factor: the UPC's transitional period is scheduled to end in 2030, though it could be extended, and once that period ends, the UPC will gain exclusive jurisdiction. This increases the strategic weight of using rights filed nationally within Germany. In this light, the fact that European patent EP3931868 landed among the postponed cases while the two utility models reached an injunction first can be read as an example illustrating the value of holding parallel national rights.
How this differs from the US staircase-structure patent that was partly struck down
Just before this ruling, a different "staircase structure" right had been struck down against YMTC in the United States. The right at issue was YMTC's US patent 12,010,838, and the post-grant review (PGR2025-00021) filed by Micron covered claims 1, 3–7, and 12–20. In early September 2026, the PTAB (US Patent Trial and Appeal Board) reportedly found these claims unpatentable. cloudnews.tech counted this as Micron's seventh win at the PTAB. This same patent is one of the rights YMTC is asserting in the N.D. Cal. case (3:23-cv-05792-RFL).
Because the names are similar, it's easy to see the German ruling and the US decision as two sides of the same right. But lining up the dates from Google Patents reveals they belong to different lineages.
| Right | Subject matter | Reference date | Latest outcome |
|---|---|---|---|
| US12010838B2 | 3D memory staircase structure | Priority date August 28, 2017 | Claims 1, 3–7, 12–20 reportedly found unpatentable (early September 2026) |
| DE202020006166U1 | 3D memory device staircase structure | Filing date March 23, 2020 | Infringement found, injunction issued by Munich Regional Court (September 18, 2026) |
The US patent, with a 2017 priority date, and the utility model, filed in 2020, stem from different originating applications. YMTC's US patent 12,010,838 (priority date August 28, 2017), whose claims the USPTAB reportedly found unpatentable in early September, and utility model DE202020006166U1 (filing date March 23, 2020), which the Munich court found infringed, both deal with staircase structures but appear to belong to different patent families. This comparison is based on dates and family information from Google Patents rather than an official family search, so the possibility of technically related content cannot be ruled out.
Even so, this distinction changes the frame of the discussion. The PTAB's decision does not directly affect the validity of the German utility models, nor did it invalidate the entire US patent — its effect is limited to the specific claims challenged. TrendForce reports that Micron has filed more than 20 invalidity petitions since 2024. The wins Micron is accumulating in the US and the injunction YMTC obtained in Germany are proceeding in parallel, on different sets of rights.
Mapping a dispute that spans seven courts
Micron's own disclosures allow the scope of the dispute to be tallied. Adding up YMTC's filings by court, as listed in the 10-Q for the quarter ended May 28, 2026, produces the following:
| Court | Filing date (service date for China) | Complaints | Asserted rights | Status confirmed |
|---|---|---|---|---|
| US N.D. Cal. | November 9, 2023; July 12, 2024 | 2 | 19 | Reportedly stayed pending IPR |
| Beijing IP Court | January 22, 2024 (service) | 3 | 3 | Unknown |
| Shanghai IP Court | September 11, 2024 (service) | 5 | 5 | Unknown |
| US E.D. Texas | October 6, 2025 | 1 | 8 | Unknown |
| UK High Court (London) | October 6, 2025 | 1 | 3 | Unknown |
| UPC Düsseldorf Local Division | October 6, 2025 | 3 | 3 | Unknown |
| Munich Regional Court I | October 6, 2025 | 5 | 5 | Injunction on 2, 3 postponed (September 18, 2026) |
| Total | 20 | 46 |
According to Micron's 10-Q, since 2023 YMTC has filed 20 complaints across seven courts — two in the US, two in China, plus the UK, the UPC, and Germany — asserting a cumulative total of 46 rights (which may include overlaps, and cover not only patents but also German utility models and European patents). The total adds up the 8 and 11 filings under N.D. Cal., 3 in Beijing, 5 in Shanghai, 8 in Texas, 3 in London, 3 at the UPC, and 5 in Munich. Since the same right can be asserted in multiple suits, these figures should be read as cumulative counts, not unique rights.
The 2024 N.D. Cal. suit covers DDR5 DRAM in addition to 3D NAND, and one LPDRAM patent is also asserted in the Texas case. "Unknown" in the table does not mean no result has been reached — only that no result could be confirmed.
What the table reveals is that YMTC expanded its litigation into four courts simultaneously on a single day, October 6, 2025. Of the seven courts listed in Micron's disclosures, the only one reported to have reached a first-instance injunction is the Munich Regional Court, with two of its five cases succeeding, while the N.D. Cal. case remains stalled pending IPR proceedings.
Outside the courtroom, Micron has also been racking up procedural wins. Bloomberg Law reported in March 2026 that Micron's declaratory judgment suit, filed in N.D. Cal. on October 7, 2025, was dismissed under the first-to-file rule because YMTC had filed in Texas the day before. A separate suit YMTC brought against Micron and lobbying firm DCI Group in the US District Court for the District of Columbia, alleging a coordinated public-opinion campaign, was dismissed by Judge Carl J. Nichols in an opinion dated August 13, 2026, which found that the publications in question did not constitute commercial speech.
YMTC was added to the US Commerce Department's Entity List (a roster of entities subject to export controls) in 2022 and remained on it as of February 2026. Despite this, it continues to pursue litigation in US federal courts. This is not a case of the company moving to Europe because it couldn't sue in the US — rather, the reality appears to be that while the US proceedings were stalled by review processes, the German proceedings simply moved faster.
How far will the injunction actually reach?
This ruling is a first-instance decision, and Micron can seek to suspend enforcement of the injunction at the Munich Higher Regional Court (Oberlandesgericht München). ip fray's Florian Mueller believes that unless the appellate court halts the injunction, enforcement is likely to begin soon. That said, neither the amount of security required for enforcement nor the specific products covered by the injunction have appeared in confirmed reporting so far.
There are also time constraints. Section 23(1) of the German Utility Models Act (GebrMG) stipulates that the term of protection begins on the filing date and ends ten years after the end of the month in which that filing date falls. Applying this provision, the two rights underlying the injunction would run, at the latest, until the end of March 2030 and the end of December 2031 respectively — meaning only about 3.5 years and 5.3 years remain from the date of the ruling. This is an upper bound that assumes renewal fees are paid and that the Google Patents filing dates match the legally recognized filing dates. Cancellation or an appellate ruling could cause the rights, or the injunction, to lose effect sooner.
The impact on supply, at this point, remains a matter of media speculation. Tom's Hardware reported that the injunction could restrict Micron's supply into Germany. However, since the injunction's scope is reported to be limited to sales within Germany, this ruling does not have any direct legal effect on consumers or businesses in Japan purchasing Micron-made SSDs or memory. There is likewise no confirmed evidence at this time that it will spill over into domestic NAND pricing or supply.
Whether the injunction becomes an actual burden for Micron will depend on three conditions: whether the Higher Regional Court declines to suspend enforcement, whether YMTC posts the required security and proceeds with enforcement, and whether the two utility models' validity holds up in separate proceedings. If all three conditions align, YMTC would end up losing individual claims one by one in the US while still holding a bargaining chip in Europe. The next hearing dates for the three postponed cases will offer the first clue as to which way this goes.