DCT
5:18-cv-00024
Panduit Corp v. Corning Optical Communications LLC
I. Executive Summary and Procedural Information
- Parties & Counsel:
- Plaintiff: Panduit Corp. (Delaware)
- Defendant: Corning Optical Communications LLC (North Carolina)
- Plaintiff’s Counsel: Tharrington Smith, L.L.P. (with Steptoe & Johnson LLP as Of Counsel)
- Case Identification: 5:18-cv-00024, W.D.N.C., 02/07/2018
- Venue Allegations: Venue is alleged to be proper as Defendant resides in the judicial district, has committed alleged acts of infringement there, and maintains a regular and established place of business within the district.
- Core Dispute: Plaintiff alleges that Defendant’s methods for manufacturing and selecting high-performance multimode optical fibers infringe patents related to a specific performance-prediction metric.
- Technical Context: The technology concerns methods for testing multimode optical fibers to more accurately predict their data-carrying capacity, a critical factor for high-speed networks in data centers.
- Key Procedural History: The complaint alleges that Plaintiff put Defendant on notice of the patents and the alleged infringement during a meeting on December 20, 2017, less than two months before the suit was filed. U.S. Patent No. 8,488,115 is a continuation of the application that resulted in U.S. Patent No. 8,351,027.
Case Timeline
| Date | Event |
|---|---|
| 2009-06-15 | Priority Date for ’027 and ’115 Patents (Provisional App.) |
| 2013-01-08 | ’027 Patent Issued |
| 2013-01-01 | Alleged Infringing Activity Commences (approx. via video reference) |
| 2013-07-16 | ’115 Patent Issued |
| 2017-12-20 | Pre-Suit Notice Allegedly Given by Plaintiff to Defendant |
| 2018-02-07 | Complaint Filed |
II. Technology and Patent(s)-in-Suit Analysis
U.S. Patent No. 8,351,027 - “Method And Metric For Selecting And Designing Multimode Fiber For Improved Performance,” issued January 8, 2013
The Invention Explained
- Problem Addressed: The patent’s background section asserts that then-current industry standards for measuring fiber optic performance, such as Effective Modal Bandwidth (EMB), were poor predictors of actual performance as measured by Bit Error Rate (BER) (Compl., Ex. A, ’027 Patent, col. 1:57-62). This could lead to fibers passing standard tests but failing in real-world, high-speed applications (’027 Patent, col. 2:6-16).
- The Patented Solution: The invention proposes a new metric, termed "DMD Shift," to more accurately select high-performance multimode fibers. The method involves measuring the delay of light pulses sent through the fiber at different radial positions, then subtracting the delay measured at a first, inner radius from the delay measured at a second, outer radius. Fibers where this calculation results in a negative number are selected as having superior performance characteristics (’027 Patent, Abstract; col. 4:20-31).
- Technical Importance: This metric was designed to provide manufacturers and network designers with a more reliable method for qualifying multimode fibers for demanding applications like 10 Gb/s Ethernet, thereby reducing the risk of difficult-to-diagnose channel failures (’027 Patent, col. 2:11-16).
Key Claims at a Glance
- The complaint primarily asserts independent claim 1 (Compl. ¶21).
- Claim 1 of the ’027 Patent recites the essential elements:
- A method for selecting multimode optical fiber for use in a communications network comprising:
- measuring the peak delay for pulses traveling through different radii of a number of multimode optical fibers;
- subtracting the peak delay at a first radius of each multimode optical fiber from the peak delay at a second, larger radius of each multimode fiber; and
- choosing for use in a communications network those optical fibers in which the result of the subtraction is a negative number.
- The complaint alleges infringement of "one or more claims of the '027 Patent, including claim 1" (Compl. ¶21).
U.S. Patent No. 8,488,115 - “Method And Metric For Selecting And Designing Multimode Fiber For Improved Performance,” issued July 16, 2013
The Invention Explained
- Problem Addressed: As a continuation, the ’115 Patent addresses the same problem as the ’027 Patent: the unreliability of existing metrics in predicting the real-world Bit Error Rate performance of multimode fibers (Compl., Ex. B, ’115 Patent, col. 2:10-20).
- The Patented Solution: The patented solution is functionally identical to that of the parent ’027 Patent, based on calculating a "DMD Shift" by measuring and subtracting pulse delays at different fiber radii. A key distinction is that the independent claim of the ’115 Patent uses the term "pulse delay" rather than the "peak delay" recited in the ’027 Patent (’115 Patent, col. 6:30-46).
- Technical Importance: The invention provides the same benefit as its parent patent: a more accurate method for sorting and selecting fibers to ensure high performance in demanding network environments (’115 Patent, col. 2:6-9).
Key Claims at a Glance
- The complaint primarily asserts independent claim 1 (Compl. ¶33).
- Claim 1 of the ’115 Patent recites the essential elements:
- A method for selecting multimode optical fiber for use in a communications network, said method comprising:
- measuring a pulse delay for pulses traveling through different radii of a number of multimode optical fibers;
- subtracting the pulse delay at a first radius of each multimode optical fiber from the pulse delay at a second, larger radius of each multimode fiber; and
- choosing for use in the communications network those optical fibers in which the result of the subtraction is a negative number.
- The complaint alleges infringement of "one or more claims of the '115 Patent, including claim 1" (Compl. ¶33).
III. The Accused Instrumentality
Product Identification
The accused instrumentalities are Defendant’s methods for manufacturing, testing, and selecting multimode optical fibers, including at least its OM4+ fiber products (Compl. ¶¶13-16, 26, 38).
Functionality and Market Context
The complaint alleges that Defendant’s manufacturing process involves using measurements to select or classify fiber optic materials (Compl. ¶16). Specifically, it alleges on information and belief that Defendant "measures the peak delay and/or pulse delay for pulses traveling through different radii of a number of multimode optical fibers to determine the design of, and to select, the fiber optic materials" (Compl. ¶16). The complaint references a marketing video allegedly explaining that Corning's manufacturing process involves measuring optical and physical parameters to verify performance (Compl. ¶16). It is further alleged that for at least its OM4+ fiber, this selection process results in a "Differential Mode Delay (DMD) profile exhibiting negative p-shift or negative relative delays," which corresponds to the negative number required by the asserted claims (Compl. ¶¶26, 38). Figure 5 of the ’027 patent, attached as Exhibit A, provides a bar chart that visually distinguishes between fibers with a desirable "Left Shift" (negative metric) and those with an undesirable "Right Shift" (positive metric), illustrating the core sorting principle of the invention (Compl., Ex. A, Fig. 5).
IV. Analysis of Infringement Allegations
’027 Patent Infringement Allegations
| Claim Element (from Independent Claim 1) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| measuring the peak delay for pulses traveling through different radii of a number of multimode optical fibers; | Defendant allegedly measures the "peak delay and/or pulse delay for pulses traveling through different radii" to test and select its fiber optic materials. | ¶16, ¶23 | col. 4:22-25 |
| subtracting the peak delay at a first radius of each multimode optical fiber from the peak delay at a second, larger radius of each multimode fiber; | After measurement, Defendant allegedly subtracts the peak delay at a first radius from the peak delay at a second, larger radius. | ¶24 | col. 4:25-28 |
| and choosing for use in a communications network those optical fibers in which the result of subtracting the peak delay at the first radius from the peak delay at the second radius is a negative number. | Defendant allegedly chooses fibers for use, such as its OM4+ fiber, where the result of the subtraction is a negative number, described as a "negative p-shift or negative relative delays." | ¶25, ¶26 | col. 4:28-31 |
’115 Patent Infringement Allegations
| Claim Element (from Independent Claim 1) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| measuring a pulse delay for pulses traveling through different radii of a number of multimode optical fibers; | Defendant allegedly measures the "peak delay and/or pulse delay" for pulses at different radii as part of its selection and classification process. | ¶16, ¶35 | col. 6:32-35 |
| subtracting the pulse delay at a first radius of each multimode optical fiber from the pulse delay at a second, larger radius of each multimode fiber; | Following the measurement, Defendant allegedly performs a subtraction of the pulse delay at a first radius from that at a second, larger radius. | ¶36 | col. 6:35-39 |
| and choosing for use in the communications network those optical fibers in which the result of subtracting the pulse delay at the first radius from the pulse delay at the second radius is a negative number. | Defendant allegedly selects its OM4+ fiber using methods that result in a negative number, corresponding to a "negative p-shift or negative relative delays." | ¶37, ¶38 | col. 6:39-43 |
- Identified Points of Contention:
- Technical Questions: A primary factual question will be whether Defendant's actual, internal quality control and selection processes for multimode fiber perform the specific measurement and calculation steps recited in the claims. The complaint's allegations are based on "information and belief" and high-level marketing materials, raising the question of what evidence discovery will yield about the specific parameters Defendant measures (e.g., peak vs. pulse delay) and the calculations it performs (Compl. ¶16).
- Scope Questions: The use of "peak delay" in the ’027 Patent versus "pulse delay" in the ’115 Patent raises the question of whether these terms have distinct technical meanings. The litigation may focus on whether Defendant's process, if it involves any delay measurement, meets the narrower definition of "peak delay," the potentially broader definition of "pulse delay," or neither.
V. Key Claim Terms for Construction
The Term: "peak delay" (’027 Patent) vs. "pulse delay" (’115 Patent)
- Context and Importance: The distinction between these two terms is critical. The complaint alleges infringement by measuring "peak delay and/or pulse delay," effectively treating them as interchangeable (Compl. ¶16). However, the use of a specific term ("peak delay") in the parent patent and a different term ("pulse delay") in the continuation suggests a deliberate choice by the patentee. The viability of the infringement case for each patent may depend on the construction of its respective term and how it maps to Defendant's actual process.
- Intrinsic Evidence for a Broader Interpretation: The specification of the ’027 Patent discusses "pulse delay" in a general sense (e.g., ’027 Patent, col. 1:33-36), which may support an argument that "peak delay" is simply one embodiment of a "pulse delay" measurement and the terms are closely related.
- Intrinsic Evidence for a Narrower Interpretation: The decision to claim "peak delay" specifically in the ’027 Patent, while the specification also describes measuring delay between the "leading edge" and "trailing edge" of pulses (’027 Patent, col. 4:2-4), suggests that "peak delay" was intended to have a precise technical meaning distinct from other types of delay measurements. The subsequent use of the different term "pulse delay" in the ’115 claims could be argued to reflect an intentional change in scope.
The Term: "choosing for use in a communications network"
- Context and Importance: This method step requires an act of selection based on the calculated metric. A central dispute may be whether Defendant's internal manufacturing process of sorting or classifying fibers constitutes "choosing" them "for use," or if that act only occurs later by a downstream customer who installs the fiber.
- Intrinsic Evidence for a Broader Interpretation: The patent abstract states the metric can be used to "select, sort, or verify fiber performance" (’027 Patent, Abstract). This language could support Plaintiff's view that an internal sorting process that qualifies fibers for sale as high-performance products satisfies this limitation.
- Intrinsic Evidence for a Narrower Interpretation: A defendant may argue that its manufacturing steps are too attenuated from the final "use in a communications network" and that it merely classifies products without "choosing" them for any specific end use, leaving that choice to its customers.
VI. Other Allegations
- Indirect Infringement: The complaint alleges both induced and contributory infringement for each patent, asserting that Defendant acts with knowledge of the patents to "actively induce others" or that others act under Defendant's "direction and control or who are in a joint enterprise" to perform the infringing methods (Compl. ¶¶19-20, 31-32).
- Willful Infringement: The complaint seeks enhanced damages and attorneys' fees, which requires a finding of willful or egregious conduct (Compl., Prayer for Relief ¶D, E). The factual basis for this allegation is Defendant's alleged pre-suit knowledge of the patents and infringement, which Plaintiff claims was established during a meeting on December 20, 2017 (Compl. ¶¶19, 31).
VII. Analyst’s Conclusion: Key Questions for the Case
- A core issue will be one of evidentiary proof: can Plaintiff produce evidence from discovery to demonstrate that Defendant’s confidential, internal manufacturing and quality control processes for its multimode fibers practice the specific "measure-subtract-choose" steps recited in the asserted claims?
- The case may also hinge on a question of claim construction: does the term "peak delay" in the ’027 Patent carry a more restrictive meaning than the term "pulse delay" in the ’115 Patent, and does Defendant's actual testing methodology fall within the scope of one, both, or neither of these definitions?
- A final key question will be one of infringement and liability: does an internal corporate process of sorting and classifying manufactured goods (optical fibers) constitute "choosing for use in a communications network" as required by the method claims, or is this action too remote from the final end use to be considered an act of infringement?