DCT
1:18-cv-01462
In Depth Test LLC v. Qorvo Inc
I. Executive Summary and Procedural Information
- Parties & Counsel:
- Plaintiff: In-Depth Test LLC (Texas)
- Defendant: Qorvo, Inc. (Delaware)
- Plaintiff’s Counsel: Friedman, Suder & Cooke; Farnan LLP
- Case Identification: 1:18-cv-01462, D. Del., 09/21/2018
- Venue Allegations: Venue is alleged to be proper based on Defendant's incorporation in Delaware and its transaction of business within the district.
- Core Dispute: Plaintiff alleges that Defendant’s semiconductor test systems and methods infringe a patent related to identifying statistical "outliers" in test data.
- Technical Context: The technology concerns statistical process control in high-volume semiconductor manufacturing, where identifying subtle performance deviations can improve yield and reliability.
- Key Procedural History: The complaint notes that the patent-in-suit has been asserted in prior litigations against other parties. It also highlights that the patent has been the subject of multiple inter partes review (IPR) and covered business method (CBM) review proceedings before the Patent Trial and Appeal Board, several of which were terminated and three of which resulted in denial of institution.
Case Timeline
| Date | Event |
|---|---|
| 2001-05-24 | U.S. Patent 6,792,373 Priority Date |
| 2004-09-14 | U.S. Patent 6,792,373 Issue Date |
| 2014 | Prior litigation involving the patent-in-suit initiated against other parties |
| 2015-01 | Defendant Qorvo formed by merger |
| 2015-2017 | Patent Trial and Appeal Board proceedings initiated on the patent-in-suit |
| 2018-09-21 | Complaint Filing Date |
II. Technology and Patent(s)-in-Suit Analysis
U.S. Patent No. 6,792,373 - "Method and Apparatus For Semiconductor Testing" (issued Sep. 14, 2004)
The Invention Explained
- Problem Addressed: The patent's background describes the difficulty in analyzing the enormous volume of data generated during semiconductor testing. Conventional methods either involved analyzing incomplete data samples, which could miss defects, or required significant processing time and storage, making real-time analysis impractical (ʼ373 Patent, col. 1:29-62).
- The Patented Solution: The invention proposes a test system where a computer, connected to the semiconductor tester, performs a supplemental statistical analysis on the test data as it is acquired ("at run time"). Instead of merely checking if a component passes or fails based on fixed limits, the system identifies components that are statistical "outliers" relative to their peers in the same batch, even if those components are technically within the acceptable control limits (ʼ373 Patent, Abstract; col. 2:17-27). This allows for a more granular classification of component quality.
- Technical Importance: This approach provided a method to identify potentially unreliable components that would otherwise pass standard tests, thereby enabling manufacturers to improve process controls and grade component performance more accurately (Compl. ¶10).
Key Claims at a Glance
- The complaint asserts at least independent claim 1 (Compl. ¶14).
- The essential elements of independent claim 1 are:
- A test system, comprising:
- a tester configured to test a component and generate test data; and
- a computer connected to the tester and configured to receive the test data, identify an outlier in the test data, and generate an output report including the identified outlier.
- The complaint reserves the right to assert infringement under the doctrine of equivalents (Compl. ¶15).
III. The Accused Instrumentality
Product Identification
The complaint identifies the accused instrumentalities as "semiconductor test systems and/or practicing infringing methods used to test/manufacture semiconductors," particularly those used in Automotive Semiconductor applications (Compl. ¶14). These systems are alleged to facilitate compliance with quality standards such as ISO/TS 16949 and AEC Q001 Guidelines For Part Average Testing (Compl. ¶14-15).
Functionality and Market Context
The complaint alleges that the accused systems are used during the fabrication process to test for manufacturing defects and include a computer that performs statistical analysis on test results (Compl. ¶15). This analysis allegedly identifies and reports components that, while within normal control limits, are "statistical 'outliers'" compared to other components from the same batch (Compl. ¶15).
IV. Analysis of Infringement Allegations
'373 Patent Infringement Allegations
| Claim Element (from Independent Claim 1) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| a tester configured to test a component and generate test data | Defendant uses test equipment during its fabrication process to test components for manufacturing defects or anomalous behavior. | ¶15 | col. 4:32-37 |
| a computer connected to the tester and configured to receive the test data | The accused test systems include a computer that receives testing results generated by the test equipment and performs statistical analysis. | ¶15 | col. 4:41-50 |
| identify an outlier in the test data | The analysis performed identifies components that fall within the control limits but that are statistical “outliers” from the other components that also fell within the control limits. | ¶15 | col. 6:42-47 |
| and generate an output report including the identified outlier | The analysis performed identifies and then reports the components that are statistical "outliers". | ¶15 | col. 18:4-9 |
- Identified Points of Contention:
- Scope Questions: A central dispute may concern the meaning of "outlier." The complaint alleges infringement by systems that perform "Part Average Testing," but it does not detail how that specific industry standard maps to the patent's claimed method of identifying outliers. The question will be whether "Part Average Testing" or similar statistical methods used by the Defendant meet the specific definition of "outlier" identification as contemplated by the patent.
- Technical Questions: The complaint's infringement theory is stated at a high level. A key technical question will be what evidence demonstrates that Defendant's systems actually perform each claimed step. For example, what evidence shows that the accused systems generate a specific "output report" that includes the identified "outlier" data, as opposed to simply using statistical data internally for process control?
No probative visual evidence provided in complaint.
V. Key Claim Terms for Construction
- The Term: "outlier"
- Context and Importance: This term is the core of the asserted claim and distinguishes the invention from simple pass/fail testing. The outcome of the case may depend heavily on whether the Defendant's statistical process controls are found to "identify an outlier" as that term is construed by the court. Practitioners may focus on this term because the patent appears to give it a specific technical meaning that may be narrower than a general statistical definition.
- Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: A party could argue that "outlier" should be given its plain and ordinary meaning in the field of statistics, which might encompass a wide range of anomaly detection techniques. The claim itself does not contain limiting language, and the specification discusses various statistical relationships and algorithms that could be used for analysis (ʼ373 Patent, col. 13:15-46).
- Evidence for a Narrower Interpretation: The specification provides a specific definition: "those test results that stray from the first set but do not exceed the control limits or otherwise fail to be detected are referred to as 'outliers'" (ʼ373 Patent, col. 6:42-47). This language, which explicitly distinguishes an "outlier" from a component that fails a test by exceeding control limits, could support a narrower construction that requires the accused system to identify anomalous-but-passing components.
VI. Other Allegations
The complaint does not contain sufficient detail for analysis of indirect or willful infringement.
VII. Analyst’s Conclusion: Key Questions for the Case
- A core issue will be one of definitional scope: Is the term "outlier," as used in Claim 1, limited to the patent's specific definition of a statistically variant component that nonetheless passes standard control limits, or can it be construed more broadly to encompass other forms of statistical anomaly detection, such as those used in industry-standard "Part Average Testing"?
- A key evidentiary question will be one of functional proof: Can the Plaintiff provide specific evidence that the Defendant’s accused testing systems perform the complete, ordered sequence of the claim—specifically, that they not only identify statistical outliers (under the court’s construction) but also "generate an output report including the identified outlier" for subsequent use, as required by the final limitation of Claim 1?