Avalanche Technology Inc v. Everspin Tech Inc

I. Executive Summary and Procedural Information

• Parties & Counsel:
  • Plaintiff: Avalanche Technology, Inc. (Delaware)
  • Defendant: Everspin Technologies, Inc. (Delaware)
  • Plaintiff's Counsel: Tensegrity Law Group LLP; Richards, Layton & Finger, P.A.
• Case Identification: 1:26-cv-00091, D. Del., 01/28/2026
• Venue Allegations: Venue is asserted in the District of Delaware on the basis that Defendant Everspin Technologies, Inc. is a Delaware corporation and therefore resides in the district.
• Core Dispute: Plaintiff alleges that Defendant's Spin-Transfer Torque Magnetoresistive Random Access Memory (STT-MRAM) products infringe four patents related to the architecture and materials of perpendicular magnetic tunnel junctions (pMTJs).
• Technical Context: STT-MRAM is a non-volatile memory technology that uses electron spin to store data, positioning it as a potential successor to traditional memory technologies like Flash and SRAM in various high-performance applications.
• Key Procedural History: The complaint notes that contemporaneously with its filing, Plaintiff provided Defendant with a copy of a complaint filed in a parallel proceeding before the U.S. International Trade Commission (ITC), an action which may suggest a strategy to seek an exclusion order to block importation of the accused products.

Case Timeline

II. Technology and Patent(s)-in-Suit Analysis

U.S. Patent No. 9,318,179 - Spin-transfer torque magnetic random access memory with perpendicular magnetic anisotropy multilayers

The Invention Explained

• Problem Addressed: The patent describes a central challenge in developing STT-MRAM: the need to reduce the electrical current required to switch a memory cell's state (write data) while simultaneously maintaining high thermal stability to prevent data loss Compl. ¶29 '179 Patent, col. 1:56-60 Prior art using single magnetic layers struggled with this trade-off, as layers thin enough for low-current switching were often thermally unstable, while thicker layers lost the necessary magnetic properties Compl. ¶29 '179 Patent, col. 2:6-24
• The Patented Solution: The invention proposes a magnetic tunnel junction (MTJ) element where the key magnetic layers (the "free layer" and "pinned layer") are not single films but are instead "composite" structures built from one or more repeats of a "bilayer unit" Compl. ¶31 This unit consists of a nonmagnetic insulating layer and an iron-rich ferromagnetic layer '179 Patent, abstract This multilayer stack is designed to enhance perpendicular magnetic anisotropy by leveraging the interfaces between the layers, thereby achieving both lower switching current and high thermal stability Compl. ¶31 '179 Patent, col. 3:45-54
• Technical Importance: This multilayer approach provided a potential architectural solution to the fundamental trade-off between write-current and data-retention stability, a key obstacle to the commercialization of high-density STT-MRAM Compl. ¶32

Key Claims at a Glance

The complaint asserts infringement of one or more claims, referencing an independent claim in an un-provided exhibit Compl. ¶48 Compl. ¶55 Independent claim 1 is representative and includes the following essential elements:

• A composite free layer including one or more repeats of a bilayer unit (comprising an insulator and magnetic layer), having a variable magnetization direction perpendicular to the layer plane.
• A magnetic pinned layer having a first fixed magnetization direction perpendicular to the layer plane.
• A tunnel barrier layer formed between the composite free layer and the magnetic pinned layer.
• A magnetic fixed layer coupled to the magnetic pinned layer through an anti-ferromagnetic coupling layer, having a second fixed magnetization direction opposite to the first.

The complaint does not specify assertion of dependent claims but may reserve the right to do so.

U.S. Patent No. 9,419,210 - Spin-transfer torque magnetic random access memory with perpendicular magnetic anisotropy multilayers

The Invention Explained

• Problem Addressed: As a continuation of the application leading to the '179 Patent, the '210 Patent addresses the same technical problems in the STT-MRAM field Compl. ¶¶33-35 These include the high write currents and poor scalability of prior MRAM devices and the challenge of balancing low switching current with high thermal stability in STT-MRAM architectures '210 Patent, col. 1:44-60
• The Patented Solution: The '210 Patent discloses a similar solution to the '179 Patent, proposing an improved STT-MRAM element with an MTJ where the free layer is a "composite" structure made of one or more "stacks" of a bilayer unit Compl. ¶37 This bilayer unit comprises a nonmagnetic insulating layer and an iron-rich ferromagnetic layer '210 Patent, col. 3:45-54 This multilayer approach is intended to enhance perpendicular anisotropy through its multiple interfaces, enabling lower switching current density while maintaining thermal stability for reliable data retention Compl. ¶37 Compl. ¶38
• Technical Importance: The technology described aims to provide a manufacturable and reliable STT-MRAM element that overcomes the critical performance trade-offs that hindered prior art devices Compl. ¶36

Key Claims at a Glance

The complaint asserts one or more claims, referencing an independent claim in an un-provided exhibit Compl. ¶63 Compl. ¶70 Independent claim 1 is representative and includes the following essential elements:

• A composite free layer including one or more stacks of a bilayer unit (comprising an insulator and magnetic layer), having a variable magnetization direction perpendicular to the layer plane.
• A magnetic pinned layer having a first fixed magnetization direction perpendicular to the layer plane.
• A non-magnetic tunnel barrier layer formed between the composite free layer and the magnetic pinned layer.
• A magnetic fixed layer coupled to the magnetic pinned layer through an anti-ferromagnetic coupling layer, having a second fixed magnetization direction opposite to the first.

The complaint does not specify assertion of dependent claims.

U.S. Patent No. 11,678,586 - Memory system having thermally stable perpendicular magneto tunnel junction (MTJ) and a method of manufacturing same

Technology Synopsis

The complaint alleges this patent addresses limitations in prior art STT-MRAM with perpendicular magnetic tunnel junctions (pMTJs), specifically the challenge of reducing switching current while maintaining high thermal stability Compl. ¶39 The disclosed solution is an MTJ architecture with a free layer composed of two ferromagnetic sub-layers separated by a thin perpendicular enhancement layer (PEL), which is alleged to reduce magnetic damping and enhance anisotropy without requiring high-temperature processing Compl. ¶40

Asserted Claims

The complaint asserts one or more claims, referencing an independent claim Compl. ¶78 Compl. ¶85

Accused Features

The Everspin Accused Products are alleged to infringe Compl. ¶79

U.S. Patent No. 10,490,737 - Magnetic memory element including magnesium perpendicular enhancement layer

Technology Synopsis

The complaint states this patent addresses the trade-off between the scalability of STT-MRAM devices and the thermal stability required for data retention, which degrades as device size is reduced Compl. ¶43 The patented solution is an STT-MRAM element with a specific MTJ structure-comprising a magnetic free layer, a reference layer, and a fixed layer separated by an anti-ferromagnetic coupling layer-designed to be thermally stable and manufacturable Compl. ¶44

Asserted Claims

The complaint asserts one or more claims, referencing an independent claim Compl. ¶93 Compl. ¶100

Accused Features

The Everspin Accused Products are alleged to infringe Compl. ¶94

III. The Accused Instrumentality

Product Identification

The accused products are STT-MRAM devices, identified as the PERSYST XSPI Octal Interface MRAM devices, PERSYST xSPI Quad Interface MRAM devices, and STT-DDR devices Compl. ¶15

Functionality and Market Context

The complaint alleges these products are high-performance, non-volatile memory that use STT technology and a perpendicular magnetic tunnel junction (pMTJ) to store data by manipulating the spin of electrons Compl. ¶13 Compl. ¶14 A diagram from Defendant's website shows an MTJ structure with a "Free Layer," "Tunnel Barrier," and "Fixed Layer," illustrating how current passes through the junction to set a magnetic state Compl. ¶14 The complaint alleges these products compete directly with Plaintiff's product portfolio and are marketed for use in industrial, Internet of Things (IoT), and embedded systems Compl. ¶12 Compl. ¶18

IV. Analysis of Infringement Allegations

Although the complaint references claim chart exhibits that were not provided, the narrative allegations supply a basis for a representative summary of the infringement theory.

'179 Patent Infringement Allegations

'210 Patent Infringement Allegations

Identified Points of Contention

• Scope Questions: A central dispute may arise over the term "composite free layer" and its requirement for "one or more repeats/stacks of a bilayer unit." The infringement analysis will likely depend on whether the specific multi-layer structure used in Everspin's products can be characterized as meeting this limitation, or if it represents a distinct, non-infringing architecture.
• Technical Questions: The complaint relies on high-level marketing descriptions of the accused products. A key question for the court will be what the evidence from reverse engineering or discovery reveals about the actual physical composition, layer structure, and material properties of the accused MTJs. The presence or absence of specific structures like a secondary fixed layer coupled through an anti-ferromagnetic coupling layer will be a critical factual determination.

V. Key Claim Terms for Construction

• The Term: "composite free layer including one or more repeats [or stacks] of a bilayer unit" (from claim 1 of the '179 and '210 Patents).
• Context and Importance: This term defines the core structure of the invention that purports to solve the trade-off between thermal stability and switching current. Infringement will likely depend on whether the layered structure within the accused products falls within the scope of this term. Practitioners may focus on this term because it is a structural limitation at the heart of the patented solution.
• Intrinsic Evidence for Interpretation:
  • Evidence for a Broader Interpretation: The specification describes the general purpose of the multilayer structure as leveraging multiple interfaces to enhance anisotropy '179 Patent, col. 3:45-54 Plaintiff may argue that any layered structure achieving this purpose using repeating two-layer units meets the claim's intent.
  • Evidence for a Narrower Interpretation: The abstract and detailed descriptions define the "bilayer unit" with some specificity as comprising "a nonmagnetic insulating layer and an iron-rich ferromagnetic layer" '179 Patent, abstract '179 Patent, col. 4:1-12 Defendant may argue the term is limited to this specific material combination and arrangement, potentially excluding other multilayer free layer designs.

VI. Other Allegations

Indirect Infringement

The complaint alleges induced infringement based on Defendant's alleged encouragement of customers and partners, such as GlobalFoundries, to manufacture and use the accused products Compl. ¶20 Compl. ¶22 It also points to the provision of "xSPI Evaluation Boards" with user guides and manuals that allegedly instruct on infringing use Compl. ¶18 Compl. ¶23 Contributory infringement is alleged on the basis that the accused MRAM devices are a material part of the patented inventions, are not staple articles of commerce, and are especially adapted for an infringing use Compl. ¶54 Compl. ¶69

Willful Infringement

Willfulness is alleged based on Defendant's knowledge of the asserted patents, which Plaintiff asserts began, at the latest, upon the filing of the complaint and a parallel ITC complaint Compl. ¶53 Compl. ¶58 Compl. ¶73 Compl. ¶88

VII. Analyst's Conclusion: Key Questions for the Case

• A core issue will be one of definitional scope: can the claim term "composite free layer including one or more repeats of a bilayer unit," which describes a specific repeating two-layer structure, be construed to read on the actual physical architecture of the free layer within Defendant's STT-MRAM products? The case may turn on whether Defendant's design is found to be a mere variation or a fundamentally different approach to solving the same technical problem.
• A key evidentiary question will be one of technical correspondence: what will discovery and technical analysis reveal about the material composition and layer-by-layer structure of the accused devices? The complaint's allegations are based on public-facing documents; the infringement case will depend on whether the physical evidence confirms that these products contain the specific multi-layer pinned and fixed layer structures required by the asserted claims.
• A third area of focus will be knowledge and intent: given the allegation of a parallel ITC filing, the court may examine the timing and nature of Defendant's awareness of the asserted patents. This will be critical not only for the willfulness claim but also for establishing the knowledge and intent elements required for the indirect infringement claims.