Technology Properties Limited LLC v. Huawei Technologies Co. Ltd.

         Appeals from the United States District Court for the Northern District of California in Nos. 3:12-cv-03865-VC, 3:12-cv-03876-VC, 3:12-cv-03877-VC, 3:12-cv-03880-VC, 3:12-cv-03881-VC, Judge Vince Chhabria.

          Thomas Cecil, Nelson Bumgardner PC, Fort Worth, TX, argued for all plaintiffs-appellants. Plaintiff-appellant Phoenix Digital Solutions LLC also represented by Barry James Bumgardner, Brent N. Bumgardner, Edward R. Nelson, III; Travis Campbell, Robert Greenspoon, Flachsbart & Greenspoon, LLC, Chicago, IL.

          Barry James Bumgardner, Nelson Bumgardner PC, Fort Worth, TX, for plaintiff-appellant Technology Propertied Limited, LLC. Also represented by William L. Bretschneider, Silicon Valley Law Group, San Jose, CA.

          Charles Thomas Hoge, Kirby Noonan Lance & Hoge LLP, San Diego, CA, for plaintiff-appellant Patriotic Scientific Corporation.

          Mark D. Fowler, DLA Piper U.S. LLP, East Palo Alto, CA, argued for all defendants-appellees. Defendants-appellees Samsung Electronic Co., Ltd., Samsung Electronics America, Inc. also represented by Erik Ryan Fuehrer, Aaron Wainscoat; James Martin Heintz, Reston, VA; Stanley Joseph Panikowski, III, Robert Chen Williams, San Diego, CA.

          Timothy C. Bickham, Steptoe & Johnson, LLP, Washington, DC, for defendants-appellees Huawei Technologies Co., Ltd., Futurewei Technologies, Inc., Huawei Device Co., Ltd., Huawei Device USA Inc., Huawei Technologies USA Inc.

          Charles M. McMahon, McDermott, Will & Emery LLP, Chicago, IL, for defendants-appellees ZTE Corporation, ZTE USA, Inc. Also represented by Hersh H. Mehta.

          Christian A. Chu, Fish & Richardson, PC, Washington, DC, for defendants-appellees LG Electronics, Inc., LG Electronics U.S.A., Inc. Also represented by Scott Andrew Elengold.

          Stephen R. Smith, Cooley LLP, Washington, DC, for defendants-appellees Nintendo Co., Ltd., Nintendo of America, Inc. Also represented by Matthew J. Brigham, Palo Alto, CA.

          Before Moore, Wallach, and Chen, Circuit Judges.

          Moore, Circuit Judge.

         The present appeals arise from five cases in the Northern District of California. Technology Properties Limited LLC, Phoenix Digital Solutions LLC, and Patriot Scientific Corp. (collectively "Technology Properties") asserted U.S. Patent No. 5, 809, 336 (the "'336 patent") against Huawei Technologies Co., Ltd., Futurewei Technologies, Inc., Huawei Device Co., Ltd., Huawei Device USA Inc., Huawei Technologies USA Inc., ZTE Corp., ZTE USA, Inc., Samsung Electronics Co., Ltd., Samsung Electronics America, Inc., LG Electronics, Inc., LG Electronics U.S.A., Inc., Nintendo Co., Ltd., and Nintendo of America Inc. (collectively "Appellees") in five separate litigations. After claim construction, the parties stipulated to non-infringement based on the district court's construction of "an entire oscillator disposed upon said integrated circuit substrate." Technology Properties appealed, and our court consolidated the appeals. Because the district court erred in a portion of its construction of "entire oscillator, " we vacate and remand.

         I. Background

         A. The '336 Patent

         The '336 patent discloses a microprocessor with two independent clocks-a variable frequency system clock connected to the central processing unit ("CPU") and a fixed-frequency clock connected to the input/output ("I/O") interface. '336 patent at 3:26-35. The variable-frequency system clock is a ring oscillator. Id. at 16:56-57. A ring oscillator is made by connecting an odd number of inverters in series, then connecting the output of the final inverter to the input of the first, creating an inherently unstable (i.e., oscillating) output. Id. at Fig. 18. A ring oscillator's frequency is considered "variable" because it fluctuates based on external stressors such as temperature and voltage. Id. at 16:59-67. For example, the same circuit will oscillate at 100 MHz at room temperature but only 50 MHz at 70 degrees Celsius. Id.

         The '336 patent's I/O clock is a quartz crystal. Id. at 17:25-27. A crystal is a piece of material that oscillates at a specific frequency when voltage is applied. Unlike ring oscillators, crystals maintain a steady frequency regardless of their environment. For this reason, the I/O clock in the '336 patent is considered "fixed." See id. at 17:33 (describing the "fixed speed" I/O interface).

         The '336 patent teaches improving microprocessor performance by decoupling the CPU and I/O clocks. The variable-speed CPU clock is fabricated on the same silicon substrate as the rest of the microprocessor, including the CPU itself. Id. at 16:57-58. Because the CPU and CPU clock are fabricated on the same silicon substrate, they react similarly to external stressors. Id. at 16:63-67. This allows the maximum processing speed of the CPU to track the oscillating frequency of its clock. As the patent describes it, the "CPU 70 will always execute at the maximum frequency possible, but never too fast." Id. at 17:1-2. The I/O clock is located off-chip and controls the chip's I/O interface. "By decoupling the variable speed of the CPU 70 from the fixed speed of the I/O interface 432, optimum performance can be achieved by each." Id. at 17:32-34. The two-clock arrangement is illustrated in Figure 17:

         (Image Omitted)

Id. at Fig. 17.

         Claim 6 of the '336 ...