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Patent practice is an area of the law in which tradition is commonly relied upon. For example, “comprising” has been established in patent law, and is recognized by courts, as being an open-ended transitional term (i.e., similar to “including”) in claim language, whereas its dictionary definitions include definitions that indicate that it may be closed-ended. However, sometimes a language construct may be thought to have a particular, “traditional” meaning that may have been used in claim drafting and construction, but which has never been formally examined to determine its actual meaning by courts. In 2004, language constructs of the form, “at least one of A, B, and C,” were carefully considered and were interpreted by the U.S. Court of Appeals for the Federal Circuit (“CAFC”) as having a particular meaning that is contrary to the “traditional” meaning, and the CAFC recently upheld this holding.

In particular, prior to February 2004, many, if not most, patent practitioners believed that “at least one of A, B, and C” was a way of stating, “at least one of A, at least one of B, and/or at least one of C.” In February 2004, the CAFC issued a decision in SuperGuide Corp. v. DirecTV Enters. that caused, or should have caused, patent practitioners to think otherwise. In that decision, the CAFC, based on principles of English grammar, established that there is a rebuttable presumption that “at least one of A, B, and C” means “at least one of A, at least one of B, and at least one of C.” This finding was based on the plain meaning of the phrase, as “at least one of” distributed over “A, B, and C,” and cited to the well-known Strunk & White treatise on English language as providing evidence of the correctness of the finding. As far as being a rebuttable presumption, the court stated, “We further conclude that nothing in the specification rebuts the presumption that the “211 patentee intended the plain and ordinary meaning of this language.” This implied that it could be possible to rebut the presumption if the patent specification provided evidence that a different construction should be used. Despite this, many patent practitioners continued to write claims using the form, “at least one of A, B, and C,” assuming that this language would interpreted as previously understood, despite the decision in SuperGuide.

During the years following the SuperGuide decision, several lower court cases were decided, in which the rebuttable presumption of the conjunctive nature of “at least one of A, B, and C” was further examined. For example, in 3rd Eye Surveillance, LLC v. United States and Rex Medical, L.P. v. Intuitive Surgical, Inc., courts held that the case of “at least one of A and B” (i.e., a list of only two items) could provide an exception to the above rule and could be interpreted disjunctively. Another exception to the rule was provided in Joao v. Sleepy Hollow Bank and Orion IP, LLC v. Staples, Inc., in which the courts held that if the interpretation of the phrase according to the grammatical rule as being conjunctive resulted in a nonsensical claim interpretation (for example, if the items are mutually incompatible), the phrase should be interpreted as being disjunctive. A number of lower court decisions including Power-One, Inc. v. Artesyn Techs., Inc  and Rowe Int’l Corp. v. Ecast, Inc looked to the specifications of the respective patents under consideration to determine whether or not the presumption of a conjunctive reading could be rebutted, as was suggested in SuperGuide.

Most recently, the CAFC rendered a decision in SIMO Holdings Inc. v. Hong Kong uCloud Network Tech. Ltd., which treated claim language of the form, “a plurality of A, B, and C.” The CAFC cited to its previous decision in SuperGuide and distinguished the case before it from the scenario in Joao, to rule that “a plurality of A, B, and C” is to be interpreted as “a plurality of A, and plurality of B, and a plurality of C” (i.e., “a plurality of” is distributed over the list of “A, B, and C”). It is noted that the CAFC brought, as an additional authority on English grammar, the more recent treatise Reading Law: The Interpretation of Legal Texts written by the late U.S. Supreme Court Justice Antonin Scalia and noted legal writing authority Bryan Garner. Perhaps the CAFC did this in response to the fact that there are those who believe that Strunk & White is outdated, to show that the principle being relied upon continues to be an accepted principle of English grammar. Consequently, SuperGuide remains authoritative as a guide in drafting and interpreting claim language containing alternative elements.

The principles of claim drafting and construction set forth in SuperGuide should never have been ignored, and now that they have been affirmed in SIMO Holdings, patent practitioners should take steps to avoid the types of language in the claims interpreted in SuperGuide and in SIMO Holdings, unless the interpretations set forth in these cases are exactly what is intended. Fortunately, there are ways to avoid the issues that arose in these cases and to obtain a disjunctive interpretation of a list of claim features.

Using the example of “at least one of,” one may simply substitute “or” instead of “and,” resulting in “at least one of A, B, or C.” An even simpler way of doing this is to simply write, “A, B, or C.” As a third example, one may present the alternatives in Markush form, i.e., as “at least one item selected from the group consisting of A, B, and C.”

For the specific case considered in SIMO Holdings, if the point was to specifically recite that a plurality of the alternatives was intended, one could write claim language of the form, “a plurality of A, B, or C,” or of the form, “a plurality of items selected from the group consisting of A, B, and C.” Note that there are other possibilities, and it should be considered whether one intends to claim a plurality that contains only one of multiple items from the list or may contain multiple versions/copies of one or more of the items from the list. For example, one may use wording like “a plurality of A, a plurality of B, or a plurality of C” to denote that a plurality of at least one of the items is intended or wording like “either a plurality of A, a plurality of B, or a plurality of C” to specifically include a plurality of only one of the items.

SuperGuide and SIMO Holdings have firmly established the conjunctive interpretation of claim language in which a term (e.g., “at least one of” or “a plurality of”) is distributed over a conjunctive listing of items (“A, B, and C”). The principles set forth in these cases should never have been ignored and should not be ignored in the future. Fortunately, there are ways in which claims may be written that avoid the issues treated in these cases, and practitioners should recognize that the “traditional” claim language was never correct, based on grammatical rules, and should be avoided unless it is specifically what is intended (i.e., a conjunctive list).

About the Author: Jeffrey W. Gluck is a partner at Panitch Schwarze Belisario & Nadel representing clients in a variety of areas including patent counseling and opinions, licensing and transactions, interferences, patent prosecution and reissue, and reexaminations. He also assists on trial litigation and has been a lead attorney in appellate litigation. Jeffrey specializes in sophisticated electrical and computer-related technologies, but his practice includes other technologies, as well.

Reprinted with permission from the May 10 issue of The Legal Intelligencer. © 2021. ALM Media Properties, LLC. Further duplication without permission is prohibited. All rights reserved.
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