A preamble may nevertheless be construed as limiting "if it recites essential structure or steps, or if it is necessary to give life, meaning, and vitality to the claim." Am. Med. Sys., Inc. v. Biolitec, Inc., 618 F.3d 1354, 1358 (Fed. Cir. 2010) (internal quotation marks omitted). Also, "[w]hen limitations in the body of the claim . . . derive antecedent basis from the preamble, then the preamble may act as a necessary component of the claimed invention."

The preamble also is not limiting if it is "duplicative" and simply "gives a descriptive name to the set of limitations in the body" such that deletion of the preamble would not affect the structure or steps of the invention. See Am. Med. Sys., Inc. v. Biolitec, Inc., 618 F.3d 1354, 1363 (Fed. Cir. 2010) (Dyk, J., dissenting) ("As the majority itself appears to recognize, we have not succeeded in articulating a clear and simple rule."); Bell Commc'ns Research, Inc. v. Vitalink Commc'ns Corp., 55 F.3d 615, 620 (Fed. Cir. 1995) ("Much ink has, of course, been consumed in debates regarding when and to what extent claim preambles limit the scope of the claims in which they appear."). Am. Med. Sys., Inc., 618 F.3d at 1358.

Such an infringing apparatus may be a machine tool apparatus that includes the claimed control features or a control apparatus that is separate from and communicates with a machine tool apparatus.Id. (emphasis added); see also Am. Med. Sys., Inc. v. Biolitec, Inc., 618 F.3d 1354, 1370 (Fed. Cir. 2010) (holding that the term "photoselective vaporization" as used in the preamble was simply "a label for the overall invention and not a limitation on the claims") (emphasis added); Schmalz, Inc. v. Better Vacuum Cups, Inc., No. 16-10040, 2017 U.S. Dist. LEXIS 144280, at *9 (E.D. Mich. Sep. 6, 2017) (stating that the term in the preamble was simply "a name for the structurally complete invention"); cf. Am. Med., 618 F.3d at 1359 (stating that, "[i]f the preamble 'is reasonably susceptible to being construed to be merely duplicative of the limitations in the body of the claim (and was not clearly added to overcome a [prior art] rejection), we do not construe it to be a separate limitation'"). IPT protests that its invention does not cover any kind of structure made up of a flange and hub (with certain dimensions); rather, its invention concerns a component of a HDD specifically.

The preamble has no separate limiting effect if, for example, "the preamble merely gives a descriptive name to the set of limitations in the body of the claim that completely set forth the invention." American Medical Systems, Inc. v. Biolitec, Inc., 618 F.3d 1354, 1359 (Fed.Cir. 2010). Still, it's not a simple matter to determine if a preamble is limiting.

Generally, the preamble does not limit the claims and, therefore, does not require construction. Am. Med. Sys., Inc. v. Biolitec, Inc., 618 F.3d 1354, 1358 (Fed. Cir. 2010). However, where "the claim preamble, when read in the context of the entire claim, recites limitations of the claim, or, if the claim preamble is 'necessary to give life, meaning, and vitality' to the claim, then the claim preamble should be construed as if in the balance of the claim."

In the opinion of Judge Dyk of the Court of Appeals for the Federal Circuit, the question of whether a preamble should be construed as limiting has been a question that the Federal Circuit has struggled to resolve. Am. Med. Sys. v. Biolitec, Inc., 618 F.3d 1354, 1363 (Fed. Cir. 2010) (Dyk, J., dissenting) (urging the Federal Circuit to address the issue en banc and advocating for a rule that a preamble acts to limit the claim). He characterized the Federal Circuit's case law on the subject to be "rife with inconsistency, both in result and in the articulation of the test," id., a view seconded by Donald Chisum, who referred to case law on the matter as "difficult to reconcile," id. at 1364 (quoting Donald S. Chisum, Chisum on Patents § 8.06[1][d] (2010)).

"Whether to treat a preamble term as a claim limitation is 'determined on the facts of each case in light of the claim as a whole and the invention described in the patent.'" Am. Med. Sys., Inc. v. Biolitec, Inc., 618 F.3d 1354, 1358 (Fed. Cir. 2010), quoting Storage Tech. Corp. v. Cisco Sys., Inc., 329 F.3d 823, 831 (Fed. Cir. 2003). Relying on expert opinion, Exergen also maintains that while the accused thermometers determine an oral equivalent temperature, they nonetheless detect human body temperature because the core temperature is the source of all temperature measurements on the body, and the oral temperature is dependent on the core temperature.

Voortman does not argue or show how the word "manufacture" as used in the preambles "define[s] or refine[s] the scope of the asserted claims," or provides "context essential to understanding" the meaning of the word "manufacturing" as used in the body of each claim. See Am. Med. Sys., Inc. v. Biolitec, Inc., 618 F.3d 1354, 1359 (Fed. Cir. 2010) (concluding that preamble's use of a "generic term" did not provide an antecedent basis for the term's use in the bodies of the independent claims). Instead, Voortman argues that the preambles should be construed to limit human intervention, indicating that the relevant preamble term is "automatic," not "manufacture."

Generally, the preamble does not limit the claims. Am. Med. Sys., Inc. v. Biolitec, Inc., 618 F.3d 1354, 1358 (Fed. Cir. 2010) (citing Allen Eng'g Corp. v. Bartell Indus., Inc., 299 F.3d 1336, 1346 (Fed. Cir. 2002)). The preamble may be construed as limiting "if it recites essential structure or steps, or if it is `necessary to give life, meaning and vitality' to the claim."

According to the Federal Circuit, although "there is no simple test for determining when a preamble limits claim scope," the court has "set forth some general principles to guide that inquiry." Am. Med. Sys. v. Biolitec, Inc., 618 F.3d 1354, 1358 (Fed. Cir. 2010). For example, because the preamble typically is not a separate claim limitation, "[i]f the preamble `is reasonably susceptible to being construed to be merely duplicative of the limitations in the body of the claim (and was not clearly added to overcome a [prior art] rejection),'" it does not limit the claims.