ARRIS Group Inc v. Cirrex Systems LLC

1. Case Identification

• Case #: IPR2015-00530
• Patent #: 6,404,953
• Filed: January 5, 2015
• Petitioner(s): ARRIS Group, Inc., Tellabs, Inc., Alcatel-Lucent USA, Inc., and Source Photonics, Inc.
• Patent Owner(s): Cirrex Systems LLC
• Challenged Claims: 1, 23, 24, 26, 31, 47, and 51

2. Patent Overview

• Title: Optical Assembly with High Performance Filter
• Brief Description: The ’953 patent relates to optical assemblies designed to reduce optical noise. The invention comprises a waveguide (such as an optical fiber), a filter in optical communication with the waveguide, and an opaque mask that adheres to one or more surfaces of the filter to block unwanted light from entering the assembly.

3. Grounds for Unpatentability

Ground 1: Claims 1, 23, and 31 are obvious over Shih

• Prior Art Relied Upon: Shih (Patent 5,546,486).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner argued that Shih discloses an optical assembly with all elements of the challenged claims. Shih teaches an optical fiber (waveguide) with an "optical barrier" (mask) made of chromium and gold applied to the fiber's end face to block unwanted light from entering the fiber's cladding, thereby reducing noise. Shih then applies an antireflection (AR) coating (filter) over the end face and the mask. Dependent claim 23 is met because AR coatings are known to be thin-film layers of alternating refractive index (e.g., titania and silica). Claim 31 is met as Shih's waveguide is explicitly an optical fiber.
  • Motivation to Combine (for §103 grounds): Petitioner contended that the AR coating taught by Shih is a type of thin-film filter. In the alternative, if the AR coating is not considered a filter, a person of ordinary skill in the art (POSITA) would have been motivated to substitute a conventional thin-film filter for Shih's AR coating. This substitution would have been a predictable design choice to further improve noise reduction by selectively filtering wavelengths, a well-known goal in the field.
  • Expectation of Success: A POSITA would have had a high expectation of success, as applying thin-film filters to fiber end faces was a common and well-understood technique for managing light transmission.

Ground 2: Claims 1, 23, 31, and 51 are anticipated by Nicholson

• Prior Art Relied Upon: Nicholson (Patent 4,883,062).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner asserted that Nicholson discloses every limitation of the claims. Nicholson teaches an optical fiber sensor that includes an optical fiber (waveguide) with an interference filter formed on its end. This filter is surrounded by an "absorbance layer" of carbon black (mask) that adheres to the outer face and peripheral edge surfaces of the filter to absorb stray light. Nicholson's interference filter is described as having alternating layers of dielectric and metal, meeting the "thin-film layers" limitation of claim 23. The mask's position on the peripheral edge surface explicitly anticipates claim 51.

Ground 3: Claims 24 and 26 are obvious over Yokoyama in view of Takashashi

• Prior Art Relied Upon: Yokoyama (Patent 5,457,558) and Takashashi ("Temperature stability of thin-film narrow-bandpass filters produced by ion-assisted deposition," a 1995 journal article).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner argued that Yokoyama discloses the base optical assembly of claim 1, including an optical multiplexer with a multi-layer dielectric filter. However, Yokoyama does not explicitly disclose the "at least 95%" packing density required by claims 24 and 26. Takashashi remedies this by teaching that high-performance filters can be produced using ion-assisted deposition (IAD) techniques to achieve "near-unity packing densities," explicitly including ranges of 0.9 to 1.0 (90-100%).
  • Motivation to Combine: A POSITA would combine Yokoyama's filter with Takashashi's deposition process for predictable benefits. Takashashi taught that high packing density improves filter performance by increasing the refractive index and reducing the degrading effects of ambient moisture. A POSITA seeking to improve the performance and reliability of Yokoyama’s high-performance multiplexer would have been motivated to use the known IAD techniques described by Takashashi to achieve a packing density of at least 95%.
  • Expectation of Success: The combination involved applying a known process (IAD) to a known device (optical filter) to achieve a predictable and desirable result (improved stability and performance). Petitioner also argued this was a matter of routine optimization, not invention.
• Additional Grounds: Petitioner asserted additional anticipation challenges based on Yokoyama alone (claims 1, 23, 31) and Naganuma (Patent 5,905,827) (claims 1, 31, 47, 51), and an obviousness challenge over Naganuma in view of Fulton (a 1994 SPIE paper) for claims 24 and 26.

4. Key Claim Construction Positions

• "waveguide": Petitioner proposed this term be construed as "an optical structure such as an optical fiber having the ability to transmit light in a bound propagation mode along a path parallel to its axis, and to contain the energy within or adjacent to its surface," consistent with the patent's specification.
• "mask": Petitioner adopted the Board's construction from a related IPR, defining "mask" as "a material that blocks the passage of at least selected photons."
• "thin-film filter": Petitioner also adopted the Board's prior construction of "a filter comprised of stacked layers for filtering light."

5. Arguments Regarding Discretionary Denial

• Petitioner asserted that review was not statutorily barred under 35 U.S.C. § 315(b), despite the petition being filed more than one year after service of the complaint in a related district court case. Petitioner argued the bar did not apply because it had timely filed a first petition (IPR2014-00815) challenging other claims of the ’953 patent, and this second petition was accompanied by a motion for joinder to that pre-existing proceeding, as permitted under 35 U.S.C. § 315(c).

6. Relief Requested

• Petitioner requested institution of an inter partes review and cancellation of claims 1, 23, 24, 26, 31, 47, and 51 of the ’953 patent as unpatentable.