Addressing whether the phrase “a plurality of” should apply to each element in a series, the US Court of Appeals for the Federal Circuit entered judgment of non-infringement, finding that the district court’s claim construction that did not require a plurality of each recited component was at odds with the claim language based on the application of grammatical rules. SIMO Holdings, Inc. v. Hong Kong uCloudlink Network Technology Limited, Case No. 19-2411 (Fed. Cir. Jan. 5, 2021) (Taranto, J.)

SIMO sued uCloudlink for patent infringement based on sales of certain GlocalMe WiFi hotspot devices and a wireless phone model. Generally, these hotspots and patented technology seek to reduce costs for calls and internet access for people traveling internationally.

The sole patent claim at issue covered an apparatus that performed certain communications protocol data transfer and authentication functions that enabled an international traveler to take advantage of a non-subscribed carrier without incurring roaming charges. At issue was the interpretation of that claim language, specifically whether the preamble, which recited a series of technological components (e.g., memory, processors, programs and, importantly here, “non-local calls database”), was a limiting part of the claim, and, if so, whether the language that recited “a plurality of” these components meant that the claimed invention must have a plurality of each of these components, or just more than one of all of them taken together. This was a determining factor for infringement, as it was essentially undisputed that the uCloudlink devices did not have one (let alone multiple) non-local calls databases. The district court concluded that the preamble language was limiting but, parsing the grammar involved and noting that specification “states that the non-local calls database is optional,” concluded that a non-local calls database was not a necessary component, and that summary judgment of infringement was warranted. UCloudlink appealed.

The Federal Circuit agreed that the preamble was limiting, but disagreed that a structure not having a recited element could infringe. The claim in issue recited “[A] wireless communication client or extension unit comprising . . .” followed by a list of components including the non-local call database. Notwithstanding that the database was found in the preamble, the Court concluded that it was limiting because it followed the term “comprising” and provided the necessary structure for the invention, which otherwise would have had no limiting description of the physical components of the apparatus. Moreover, the Court noted that subsequent claim language, which recited “the wireless communication client” and “the extension unit,” referred to those items identified in the preamble after “comprising.”

The Federal Circuit relied on many grammatical canons, its own precedent, various Scalia & Garner textualist interpretation books and the law-school writing-class favorite, Strunk & White. Applying these sources together, the Court reiterated that nouns in series are generally each treated as modified by a phrase that precedes the series (here, “a plurality of”), and that such a rule is particularly forceful when the series ends in an “and” rather than an “or.” And, with no article preceding “non-local calls databases,” which ended the list, there was nothing that set the phrase apart from the rest of the series. Finally, after the list, certain components were expressly called out as already existing in a plurality (e.g., “the plurality of programs”), which moved the interpretive needle toward concluding that a plurality of each member of the series—including the non-local call databases—was required.

Notably, the Federal Circuit’s interpretation excluded some embodiments from the specification. This conflict was dismissed by the Court, which noted that exclusion of some embodiments can be appropriate where required by the claim language and where such embodiments are otherwise claimed (here, other claims lacked a requirement of “non-local call databases”), particularly where such embodiments are not identified as preferred.

Practice Note: For claims drafters, the opinion provides an important reminder to ensure precision in ordinary grammatical usages to reflect the intended meaning.