Federal Circuit No. 2014-1305, August 2, 2015
Inline Plastics Corp., is a claim construction appeal from a district court finding of non-infringement based on the construction of “tamper evident bridge” and “frangible section” in U.S. Patent No. 7,118,003 (“the ’003 Patent”). The ’003 Patent relates to plastic food containers that include a tamper evident seal, which the end user breaks to open the container. At issue was the number of score lines that delimit the tear strip. The accused product use a single score line along which the cover is severed from the base, whereas, the ’003 Patent specification describes and depicts embodiments having two parallel score lines above and below the tear strip, such that in operation the tear strip is fully removed.
Summary of Inline Plastics Corp. v. Easypak, LLC, 2014-1305
The district court relied on the disclosure of the specification and prosecution history to require that the claimed “tamper evident bridge” and “frangible section” include “a removable tear strip, delimited by at least two several score lines.” The Federal Circuit Panel reversed, finding that the district court erred in (1) importing limitations from a preferred embodiment in the specification and (2) relying on the prosecution history to limit claim scope without sufficient disclaimer.
First, regarding the specification, the district court found that the claims were unclear as to how a frangible section is removed (1 or 2 lines); the specification refers to frangible section 90 times, 42 of which specify that the frangible section must be removed (i.e., at least 2 score lines); and, nearly every drawing shows the frangible section attached by two parallel score lines or completely removed in the process of removal. The Panel found that the frequency with which a particular embodiment is described, without more, is not determinative of claim scope. In this case, a single disclosure of an alternative one score line embodiment supported a broad claim scope.
Regarding prosecution history, the district court found that “declarations made during patent prosecution to surpass the prior art reveal a definitive focus on the removability of the frangible section and thus clearly and unambiguously disavow any other embodiment to the contrary.” The Federal Circuit Panel disagreed, finding that (1) the applicants never distinguished the claimed invention on the basis of score lines, (2) declarants did not address the number of score lines in the frangible section, and (3) the patent examiner placed no emphasis on the number of severable lines. The Panel concluded that there is no discussion in the prosecution history of any patentability reliance on the number of score lines by which the frangible section is severed.
This case is instructive by showing the high threshold for restricting claim scope based on disavowal or disclaimer in the specification or prosecution history. The specification requires specific language adopting a particular embodiment or criticizing an alternative embodiment – frequency alone is insufficient. During prosecution, reference to a particular feature does not establish a disclaimer - there must be some “patentability reliance” either by the applicants or by the examiner.
