In Inline Plastics Corp. v. EasyPak, LLC, the Federal Circuit offered some bits of wisdom for patent application specification drafting, while applying well-known case law to conclude that claims are not limited to a specific embodiment when the specification includes a broader disclosure.

Inline Plastics Corporation sued EasyPak, LLC for infringement of U.S. Patent No. 7,118,003 (the '003 patent) and No. 7,073,680 (the '680 patent), directed to tamper-resistant plastic food containers.  Following the District Court's claim construction, Inline moved for entry of final judgment of non-infringement of its own '003 patent, on the premise that the claims as construed are not infringed.  Presumably, Inline did so in order to obtain a final judgment necessary for appeal.

The '003 patent covers plastic food containers with a tamper-evident and tamper-resistant feature.  The containers have a hinged plastic bridge between the top and bottom portions of the container, and the bridge has a frangible section that must be severed in order to open the container.  Thus, tampering or opening of the container is readily evident.  Figure 1 of the '003 patent shows an embodiment of the tamper-resistant container, and is reproduced below:

Claims 1 and 2 are representative:

1.  A tamper-resistant/evident container comprising:
    a) a plastic, transparent cover portion including an outwardly extending peripheral flange;
    b) a base portion including an upper peripheral edge forming at least in part an upwardly projecting bead extending substantially about the perimeter of the base portion and configured to render the outwardly extending flange of the cover portion relatively inaccessible when the container is closed; and
    c) a tamper evident bridge connecting the cover portion to the base portion.

2.  A tamper-resistant/evident container as recited in claim 1, wherein the tamper evident bridge includes a hinge joining the outwardly extending flange of the cover portion with the base portion, the hinge including a frangible section, which upon severing, provides a projection that extends out beyond the upwardly projecting bead of the upper peripheral edge of the base portion, for facilitating removal of the cover portion from the base portion to open the container.

The District Court construed "frangible section" to mean "a removable tear strip, delimited by at least two severable score lines."  This was a problem for Inline because while EasyPak's accused containers embody all of the elements of claims 1 and 2, the EasyPak frangible section has a single score line along which the cover is severed from the base.  Thus, using the District Court's claim construction, EasyPak could not infringe.

The District Court acknowledged that it limited the claims to the embodiment shown in Figure 1, and recognized that claims 1 and 2 did not contain a limitation to two severable score lines, but reasoned that the prosecution history supported this limitation.

Claim Term "frangible section"

The '003 specification describes the invention's features as "intended to prevent and deter opening container 10 without first removing frangible strip 18 from hinge 16."  The specification does use language such as "preferably" to describe the embodiment (e.g., "Preferably, frangible strip 18 is limited at least in part by a pair of parallel score lines 42a, 42b or areas that have been weakened or stressed during the forming process").  But, the specification also states that a single score line or perforation is an alternative embodiment.

Despite this explicit disclosure of an alternative single score line, the District Court limited "frangible section" to require at least two score lines.  The District Court referred to the frequency with which the specification described the frangible section as having two score lines that form a severable strip as support for doing so, and used a passing reference to the prosecution history as a secondary basis.

The Federal Circuit noted that the preferred embodiment is not described as having certain unique characteristics of patentable distinction from other disclosed embodiments.  Nor are traditional aspects of restrictive claim construction present (e.g., no disavowal or damaging statements present in the specification), and thus, Inline is entitled to claim scope commensurate with the invention that is described in the specification.

The Federal Circuit also analyzed the prosecution history, and found no support for any estoppel or disclaimer of claim scope.  The Federal Circuit found that during prosecution, Inline distinguished its invention from cited art on the basis that "[n]owhere in [cited art] is there any disclosure, teaching or suggestion to modify the container therein to provide a tamper evident bridge that connects a cover portion to a base portion."  The distinction between the cited art and the '003 device has no relation to the number of score lines on a tear strip, but rather to differences in the structure and opening mechanism as a whole.

EasyPak attacked Inline over phases of the prosecution asserting that a declaration submitted for long-felt need limited the claims to having two score lines, and that other declarations submitted for commercial success had the same limiting effect.  The Federal Circuit found no such statements in the declarations, and also noted that the patent examiner placed no emphasis on the number of severable lines whatsoever in making the determination of allowable subject matter.

The Federal Circuit noted that there simply is no discussion in the specification or the prosecution history of any patentability reliance on the number of score lines by which the frangible section is severed.

The doctrine of claim differentiation also supported Inline, in that Claim 4 depends from claim 2 and is specific to the embodiment of two parallel score lines.

Thus, the Federal Circuit found that the District Court erred in limiting the claims to a specific embodiment.

Claim Term "tamper evident bridge"

Construction of this claim term was also found to be in error since it similarly relied on the "two score lines".  The Federal Circuit reconstructed it to be "at least one".

It is curious to note the District Court's strict conclusion and reliance on a "preferred embodiment" that ignored the patent application's explicit recitation of alternatives so as to issue a limiting claim construction.  An odd reference to a "frequency with which the specification described the frangible section as having two score lines that form a severable strip," is not enough for this conclusion.  Generally, this will always be the case, in which the invention is overwhelmingly described in terms of a "preferred embodiment", and thus, will have a high frequency of description of that manner.  Other alternatives of the invention are usually described with less frequency in the specification, or even mentioned only one time per alternative.  Making sure that each alternative is recited the same number of times would result in redundant descriptions and lengthy patent applications, and just does not make sense to do.

In any event, it is long-standing case law that for broad patent disclosures, i.e., those that include description of many embodiments, absent any disavowal of claim scope or specific language in the specification limiting to one/preferred embodiment, claim terms should not be so limited.  And, here, the Federal Circuit followed such law.

Inline Plastics Corp. v. EasyPak, LLC (Fed. Cir. 2015)
Panel: Circuit Judges Newman, Clevenger, and Dyk
Opinion by Circuit Judge Newman