Holding: Method claims ordinarily do not require the recited steps to be performed in a specific order unless inherent logical or functional dependencies in the claim language compel a particular sequence.
Sound View owns US Patent No. 6,708,213, which discloses a method and apparatuses for reducing network latency and increasing the quality of media streamed to devices of users. This method uses intermediate helper servers (HSs) that cache content, coordinate distribution, and adjust data transfer rates. The HS receives a streaming media (SM) object request from a client computer and typically only stores one part of the requested SM object. The HS then has to retrieve the rest of the content from the other HSs in the network.
Claim 16 of the ‘213 Patent recites a method that comprises receiving a request for an SM object, allocating a buffer at one of the HSs to cache at least a portion of the SM object, downloading the portion of the SM object to the client and concurrently retrieving a remaining portion of the SM object from another HS, and adjusting a data transfer rate from the HS to the client.
Sound View sued Hulu for infringement of six of their patents, and only claim 16 of the ‘213 remained at issue. Sound View alleged that Hulu used third-party edge servers as HSs to deliver content to customers. However, the District Court granted summary judgment of non-infringement, finding that Hulu’s edge servers did not download and retrieve subsequent portions of the same SM object in the same buffer. This judgment was overturned by the Federal Circuit in a previous case, and the Federal Circuit remanded with instructions to construe the term “buffer.”
On remand, the district court construed the term “buffer” to mean “short term storage associated with said requested SM object.” Based on this construction, the district court once again granted summary judgment of non-infringement to Hulu. In its summary judgment ruling, the district court provided additional claim constructions, determining that the receiving step of claim 16 must be performed before the allocating step. The district court also determined that claim 16 required a specialized buffer specifically associated with the requested SM object rather than a general buffer.
The Federal Circuit found that the district court erred in construing the term “buffer” to require a buffer that is associated with a specific SM object. Relying on the plain and ordinary meaning of the word “buffer,” the Federal Circuit did not find anything in the claim language that would require the buffer to be associated with a single SM object. The specification discussed a couple of examples of specialized buffers, but this disclosure did not provide a clear and unmistakable disclaimer that the general purpose buffer of claim 16 should only be associated with a single SM object. Given the intrinsic evidence, the Federal Circuit ruled that the plain and ordinary meaning of “buffer” as a general buffer should be used.
Despite finding that the district court erred in its construction of the term “buffer,” the Federal Circuit agreed with the district court that claim 16 required a specific sequence for the first two steps. The first step recites “receiving a request for an SM object from one of said plurality of clients at one of said plurality of helper servers.” The second step recites “allocating a buffer at one of said plurality of HSs to cache at least a portion of said requested SM object.”
It is a general rule that steps in a method claim are not construed to require an order unless the steps of the claim actually recited an order. However, a claim may require an ordering of steps when the claim language, either through logic or grammar, requires that the steps be performed in the order written. Alternatively, the specification may directly or implicitly require an order of steps. In this case, the Federal Circuit held that both grammar and logic indicate that claim 16 required the receiving limitation to be performed before the allocating limitation.
The “request for an SM object” recited in the first limitation provides the antecedent basis for “said requested SM object” recited in the second limitation. According to the Federal Circuit, using the adjective “requested” to modify the noun “SM object” presents a logical relationship requiring the request to occur before the SM object can be described as being requested. By using the phrase “requested SM object” in the second limitation to reference the first limitation, it logically follows that the second limitation must occur after the first limitation.
Sound View argued that claims 10 and 13 in the ‘213 Patent present examples of method claims that require a specific order, and claim 16 does not include the same grammatical structures. However, the Federal Circuit refused to import limitations from these claims into claim 16. Sound View also argued that a claim should only require a certain order if the later recited step cannot be performed without first performing the earlier step. However, the Federal Circuit found this rule unsupported by case law. Instead, the claim language and specification determine whether the steps need to be performed in a certain order.
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