Patent claims must be written with sufficient clarity to inform those skilled in the relevant technology (i.e. “skilled in the art”) about the scope of the invention with reasonable certainty. That way competitors of the inventors can know when they may be infringing. This is a basic notice function of a patent. Its scope must be ascertainable with reasonable certainty. Patent claims that fail this test are referred to as “indefinite” and they are invalid.
For example in Horizon Pharma Inc. v Dr. Reddy’s Laboratories Inc. (Fed Cir January 6, 2021) (nonprecedential), the U.S. Court of Appeals for the Federal Circuit found that the way the word “target” was used in patent claims rendered the patent claims indefinite. The Federal Circuit therefore affirmed the judgment of the U.S. District Court for the District of New Jersey that had found the claims invalid as indefinite.
The problem was the use of the word “target” in an unconventional way. Claim 1 recited in part:
1. A method for treating osteoarthritis, rheumatoid arthritis, or ankylosing spondylitis comprising orally administering to a patient in need thereof an AM unit dose form and, 10 hours (±20%) later, a PM unit dose form, wherein:
the AM and PM unit dose forms each comprises:
naproxen, or a pharmaceutically acceptable salt thereof, in an amount to provide 500 mg of naproxen, and esomeprazole or a pharmaceutically acceptable salt thereof in an amount to provide 20 mg of esomeprazole;
said esomeprazole, or pharmaceutically acceptable salt thereof, is released from said AM and PM unit dose forms at a pH of 0 or greater,
the AM and PM unit dose forms target:
i) a pharmacokinetic (pk) profile for naproxen where:
the AM and PM unit dose forms further target a mean % time at which intragastrical pH remains at about 4.0 or greater for about a 24 hour period after reaching.
Opinion pp. 3 – 5 (Bolding of “target” added). Thus, the word “target” is used twice. First, it is used in the phrase “the AM and PM unit dose forms target:” and also in the phrase “the AM and PM unit dose forms further target.” In both of the above phrases, the noun or actor is a “dose.”
The first issue was the meaning of the word “target” itself. The patent owner (plaintiff-appellant) Horizon Pharma argued that as used in the claim the word target means only “produce.” That is, just producing a result. But the defendant-appellee Dr. Reddy argued that “target” has its ordinary meaning of “with the goal of obtaining.” It must be remembered from above that “dose” in the noun or actor. That is, it is a “dose” that is “targeting.”
The Federal Circuit noted that “The words of a claim are generally given their ordinary and customary meaning” citing “Phillips v. AWH Corp., (Fed Cir 2005) (en banc). Further, “the ordinary and customary meaning of a claim term is the meaning the term would have to a person of ordinary skill in the art in question at the time of the invention.” Opinion p. 7.
Applying the above, the Federal Circuit found that “target” is a commonly understood word and that its ordinary and customary meaning is to “set as a goal.” In reaching this conclusion, the Court reviewed relevant passages of the patent and concluded that there was nothing in the written description of the patent that changed the above ordinary and customary meaning. The Federal Circuit did agree that it is possible for a patent to give a claim term a special meaning that is different from its ordinary and customary meaning, but it found that the patent in this case did not give “target” any special meaning. Therefore, the Federal Circuit concluded that as used in claim 1 the word target meant “set as a goal.”
Having construed the term “target” the Federal Circuit then set forth the test for whether a claim is indefinite: “Patent claims are indefinite if they do not inform those skilled in the art about the scope of the invention with reasonable certainty.” Citing Nautilus, Inc. v. Biosig Instruments, Inc. (Fed Cir 2014). The issue in this case was not that the meaning of “target” was unclear. As noted above, the Federal Circuit was able to provide a meaning for the word “target.” The problem was the use of the word “target.”
The Federal Circuit noted that one circumstance where patent claims are indefinite is if the claims, as properly construed, are “nonsensical.” Opinion p. 9. Recall from above that the noun or actor in the phrases using the word target is a “dose.” The Federal Circuit noted that “Reading the claim literally, a dose form which is an inanimate object, cannot set a goal.” Thus the wording of the claim requiring a “dose” to “set a goal” was nonsensical. The meaning of those above phrases could not be ascertained with reasonable certainty. And the claims were indefinite and invalid. Therefore, the Federal Circuit affirmed the lower court’s holding that the claims of the patent were invalid for indefiniteness.