Oyster Optics, LLC v. Ciena Corporation, AT&T, Inc.
- Jeffrey White
- 4:20-cv-02354
- U.S. District Court · Northern District of California
- 13
In Oyster Optics v. Ciena, Judge White defined disputed terms in a fiber-optics patent without deciding infringement.
Oyster Optics, LLC and Ciena Corporation, the parties to the patent dispute; the constructions govern the meaning of disputed terms in the ’500 Patent claims at issue.
What happened
Oyster Optics, LLC sued Ciena Corporation, alleging infringement of patents involving fiber-optic communications. After proceedings involving a stay and patent-review decisions, the court held a hearing to determine the meaning of disputed terms in the remaining patent claims.
The court defined “phase modulate” as altering light’s phase to create an optical signal whose phase represents data. It gave related terms the corresponding meaning, defined “amplitude-modulate” as altering light’s amplitude to create an optical signal whose amplitude represents data, and required an interferometer to measure interference produced by splitting and recombining light, with at least one beam delayed before recombination.
The order left the term “mode” for a later supplemental order and stated that the court would schedule another case-management conference in that order. Judge White issued the claims-construction order on July 11, 2022.
The detailed version
- Oyster Optics, LLC v. Ciena Corporation, AT&T, Inc. · No. 4:20-cv-02354
- Jeffrey White
- July 11, 2022
Background
Oyster Optics, LLC alleged that Ciena Corporation infringed U.S. Patent Nos. 6,665,500 and 10,554,297. The parties later stipulated to dismiss the claims and counterclaims concerning the ’297 Patent. After a stay related to inter partes reviews—proceedings in which the Patent Trial and Appeal Board reviews patent validity—Oyster limited its claims to claims 5 and 16 of the ’500 Patent. The Patent Trial and Appeal Board had found several other claims invalid, while finding that the petitioner had not proved dependent claim 5 invalid; appeals were pending before the Federal Circuit.
This order concerned claim construction, meaning the court’s determination of the meaning and scope of patent claims. The disputed terms were “phase modulate” and its variants, “amplitude modulate” and its variants, and “a receiver having an interferometer.” The court stated that it would address “mode” in a supplemental order after further briefing.
Claim Construction
“Phase modulate” and related terms
The parties disagreed primarily about whether “phase modulate” excludes amplitude modulation. The court rejected Ciena’s proposed limitation that phase modulation cannot include amplitude modulation. It relied on the claims and specification, which describe systems using phase modulation, amplitude modulation, or both, as well as persuasive claim-construction decisions concerning the same patent in related litigation.
The court construed “phase modulate” to mean: “alter the phase of light to create an optical signal having a phase that is representative of data.” The court gave “phase modulated [optical] signals” no additional construction beyond that definition. It construed “phase modulator” to mean: “a device that alters the phase of light to create an optical signal having a phase that is representative of data.”
“Amplitude modulate” and related terms
The court also rejected Ciena’s proposed limitation that amplitude modulation cannot include phase modulation. It construed “amplitude-modulate[ing]” to mean: “alter[ing] the amplitude of light to create an optical signal having an amplitude that is representative of data.”
“A receiver having an interferometer”
Oyster proposed a broader construction based on measuring interference phenomena from signal and reference beams. Ciena proposed a more specific construction requiring the receiver to split light into two waves, delay one, recombine them, and detect the recombined intensity.
The court did not adopt Ciena’s proposed construction in full, because it would improperly limit the claim to one configuration. However, the court concluded that the specification and inventor testimony supported requiring the interferometer to separate and recombine light and to use interference for measurement. The court construed “a receiver having an interferometer” to mean: “a receiver having a device that performs a measurement using the interference phenomena produced by the splitting and recombining of one or more beams of light where at least one of those beams of light is delayed before recombining with other beams of light.”
Disposition and Remaining Proceedings
The court entered the stated constructions for the three disputed terms. It reserved construction of “mode” for a supplemental order and said it would set a further case-management conference in that order. The order was signed by Judge Jeffrey S. White on July 11, 2022.
Read the full 13-page opinion on CourtListener, the free public archive maintained by the Free Law Project.