Google LLC v. Sonos, Inc.

Background

Google accused Sonos of infringing claims in three patents. The parties appeared for a claim-construction hearing, where they asked the court to interpret nine terms. They stipulated to dismissal of the infringement claims involving the ’206 patent, leaving eight terms for decision in the patents identified in the opinion as the ’187, ’375, and ’586 patents.

Claim construction is the process of determining what disputed patent-claim language means. The court generally applies the ordinary meaning that a person of ordinary skill in the relevant technology would understand, while considering the patent claims, specification, prosecution history, and, to a lesser extent, outside evidence. The court also addressed whether certain language was governed by 35 U.S.C. § 112(f), which limits a functional claim element to the corresponding structure described in the patent and its equivalents.

The Court’s Constructions

1. “Domain information” — ’187 patent. The court adopted the plain and ordinary meaning proposed by Sonos. It found that the surrounding claim language already made clear that the term referred to information concerning an existing group of devices sharing rights through a common account for accessing protected digital content. The court rejected Google’s more detailed construction as redundant.

2. “Logic circuitry” — ’187 patent. The court adopted Google’s construction: plain and ordinary meaning, not governed by § 112(f). Because “circuitry” and “logic” together conveyed a sufficiently definite class of structures to a skilled person, Sonos did not overcome the presumption that § 112(f) did not apply.

3. “Private key” — ’187 patent. The court adopted Google’s construction: “a non-public key that is used as an input to a cryptographic algorithm designed such that, without the key, the output of the algorithm cannot be computed.” The court concluded that the patent did not clearly redefine the term or disclaim its full scope. Although the preferred embodiment described public-key cryptography, the patent also stated that alternate security techniques, including symmetric-key techniques, were covered.

4. “Combined search results set” and related language — ’375 patent. The court adopted Sonos’s construction: the set must include two or more of the following: one or more favorite items, one or more search results from a first global index, or one or more search results from a second global index. The court rejected Google’s proposed requirement that the set include at least one personalized search. It held that the claim language expressly allowed a set consisting only of results from the first and second global indexes, and the court could not rewrite the claims to correct a possible drafting error.

5. “Stored [for the user] in a client-side storage of a client device” — ’375 patent. The court adopted Sonos’s construction: information must be retained in a computer-readable medium of the client device for later retrieval by the user, and transitory storage is excluded. The court therefore held that temporary storage, such as information fleetingly held in random access memory while being sent to a server, was outside the term’s scope.

6. Preambles of claims 1 and 15 — ’586 patent. The court adopted Google’s construction and held that the preambles are limiting. The references to an audio-enabled wireless device and a wireless mesh network supplied structure and context for the claim limitations. The court noted that a mesh network is understood as having the capability to connect nodes through multiple wireless paths.

7. “Reset element” — ’586 patent. The court held that the term means “hardware that places the controller in a prescribed state.” It adopted this construction after the parties revised their proposals and found that the reference to the audio-enabled wireless device in Google’s proposal was already apparent from the claim’s context.

8. “Preamble portion” — ’586 patent. The court adopted the plain and ordinary meaning and rejected Sonos’s proposed requirement that the term mean a series of bits used to initiate and synchronize the receiving device. The court found that the outside technical evidence was disputed and did not justify adding that limitation to the claim language.

Disposition and Significance

The court entered the claim constructions described above. The opinion did not decide whether Sonos infringed the patents or whether the patent claims were valid. It determined the meanings and scope of the eight disputed terms for the continuing patent case.