Federal Circuit: Claim Construction Limited When Essential Structure Only in Preamble


The Federal Circuit has ruled that the preamble in a claim in a patent application can be limiting when it supplies “essential structure” and the body of the claim does not define “a structurally complete invention.”

SIMO Holdings Inc v Hong Kong Ucloudlink Network Technology Ltd involves a patent for “apparatuses and methods that allow individuals to reduce roaming charges on cellular networks when traveling outside their home territory.”

The court explained that

the patent notes that one way the user can avoid the roaming charges involves replacing a physical component of the phone—specifically, replacing the subscriber identity module (SIM) card inside the phone that identifies the phone to an in-reach cellular network. The user can replace the home-network SIM card … with a SIM card used for a "local" call on a cellular network in the user's present location….

However, according to the court, swapping SIM cards is “inconvenient, inefficient, and technically challenging for most subscribers, especially when traveling to multiple foreign countries.”

The patented invention purports to solve that problem.

SIMO, the patent owner, sued uCLoudlink and its US subsidiary, claiming that four uCloudlink products infringed SIMO’s patent.

The preamble of Claim 8 of the application recites:

A wireless communication client or extension unit comprising a plurality of memory, processors, programs, communication circuitry, authentication data stored on a subscribed identify module (SIM) card and/or in memory and non-local calls database, at least one of the plurality of programs stored in the memory comprises instructions executable by at least one of the plurality of processors for: …

(Emphasis in court decision.)

uCLoudlink argued that its product didn’t have a “plurality of . . . non-local calls database[s]” and thus that its product didn’t infringe the patent.

The court noted that

SIMO cites no authority holding a preamble not limiting in this situation, where the body identifies nothing but functional properties of the claimed apparatus. Our precedent explains why the preamble in this situation is limiting. In supplying the only structure for the claimed apparatus, the preamble language supplies “essential structure,” and the body does not define “a structurally complete invention”—which are two key reasons for preamble language to be deemed limiting.

The court pointed out that the patent was so badly written that it wasn’t clear what it was claiming:

the mix of plural, singular, and mixed-use forms of words in the list following "a plurality of" ("memory," "processors," "programs," "circuitry," "data," "database") leaves the phrase "a bit of a mess grammatically."

…given the collective character of the singular-form words, the extent of the divergence from standard American English, at least as used in patents, is not entirely clear.

The court noted that “a plurality of” means “at least two of,” and

If "at least one of" requires one or more of each item in a conjunctive list, "a plurality of" requires two or more of each item in a conjunctive list—such as claim 8's list joined by "and."

The fact that there was no article (“the” or “a”) before "non-local calls database" was also a source of confusion:

If the series modifier did not apply to all members of the group, a relevant artisan would expect an "a" before "non-local calls database" (and perhaps "memory"). That is because "[t]he typical way in which syntax would suggest no carryover modification is that a determiner (a, the, some, etc.) will be repeated before" one of the items in the list.

The court granted summary judgement of non-infringement to uCLoudlink and noted that it was up to SIMO to make sure that its patent claims were properly drafted:

The textual sloppiness—which SIMO had the obligation as the patent drafter to avoid—provides no significant textual counterweight to what we conclude are the decisive textual considerations already discussed that favor uCloudlink's narrower reading of "a plurality of" as applying to each item in the list following that phrase.

Categories: Patents