Its More Than a Presumption, It's a Rule: "A" Means "One or More"

Baldwin Graphic Systems, Inc., v. Siebert, Inc., [2007-1262](January 15, 2008)[RADER, Michel, Moore] The Federal Circuit The Federal Circuit affirmed-in-part, reversed-in-part, and remanded the case because the district court erred in its construction of some of the disputed claim terms.
SIGNIFICANCE: "A" means one or more, unless there is something specific in the claim, specification, or prosecution history to the contrary. Process limitations should not be read into apparatus claims. The order of steps in a method claim is not important, unless the claim, specification, or prosecution history clearly indicates otherwise
BRIEF: The district court construed "a pre-soaked fabric roll" to mean "a single pre-soaked fabric roll, " concluding that "a" means "one" in this context because of the subsequent use of "said fabric roll" as suggesting a singular fabric roll. The Federal Circuit was firm in rejecting this construction of "a" "This court has repeatedly emphasized that an indefinite article ‘a’ or ‘an’ in patent parlance carries the meaning of ‘one or more’ in open-ended claims containing the transitional phrase ‘comprising.’" The Federal Circuit said that That "a" or "an" can mean "one or more" is best described as a rule, rather than merely as a presumption or even a convention. The exceptions to this rule are extremely limited: a patentee must evince a clear intent to limit "a" or "an" to "one."
The Federal Circuit also rejected the district court's interpretation that read process limitations into the apparatus claims, or which imposed an order of steps in the process, not mandated by the claims themselves, or anything in the specification or prosecution history.