Successor Corporation Held Liable for Default Infringement Judgment Against Predecessor

DaewooFunai Electric Company v. Daewoo Electronics Corp. (Fed. Cir. 2010)

In 2004, Funai Electric sued four Daewoo entities for infringement of its patents covering various improved video cassette recorders (VCRs). Funai is a Japanese manufacturer of AV equipment. Daewoo was a historic Korean chaebol that splintered after a financial collapse in the late 1990’s.

Successor Liability: Two of the Daewoo defendants are predecessor companies of the other two defendants. One predecessor-successor pair includes Korean companies and the other pair includes their American counterparts.  At the time of the lawsuit, the two predecessor companies had legally transferred assets to their successors but had not yet ceased operations.  About one-year into the lawsuit, the two predecessor companies stopped participating in the litigation. The district court ordered a default judgment and awarded $8 million in default damages.  Funai then asked that the successor companies be held liable for the liabilities of their predecessors. The district court applied Korean corporate and contract law to hold that there is no successor liability. 

On appeal, the Federal Circuit reversed that judgment — holding that US successor-liability law (actually, New Jersey law) should apply when determining whether the American successor company is liable for the actions of its predecessor. Under New Jersey law, a successor company is liable when the business transfer is simply a “new hat” for the business. Since that was the case here, the Federal Circuit determined that the successor is liable for the default judgment.

The 50–page opinion (including a concurrence by Judge Linn) discussed several other issues. Notably, the opinion provides another example of a prosecution amendment made for purposes “tangential to patentability” and that therefore avoids prosecution history estoppel.

Prosecution History Estoppel: Funai argued that one of its asserted claims was infringed under the doctrine of equivalents (DOE).  Daewoo countered that DOE should be limited under the doctrine of prosecution history of estoppel based on a narrowing amendment made during prosecution of the application. In particular, the patentee had cancelled claims 1 and 2 and then added limitations from those claims into a former dependant claim.  The original claim 1 did not spell-out how insulation would take place while the amended claim indicated that a bearing holder would be “made of an insulating material.”

Under the Supreme Court’s Festo decision, an amendment made during prosecution does not implicate a prosecution history estoppel bar if the “rationale underlying the amendment [bears] no more than a tangential relation to the equivalent in question.”  On appeal, the Federal Circuit recognized the amended claim set as being narrowed, but held that “no estoppel exists” because amendment relating to the insulating material was made for purposes merely tangential to the patentability of the claim. 

It is apparent that the nature of the insulating material was not a factor in the allowance of claim 4, for this aspect was not at issue during prosecution. This limitation is in the category that the Court called “merely tangential” to the prosecution, as discussed in Festo.

The court therefore affirmed the holding of infringement under the doctrine of equivalents.

Adams Respiratory Therapeutics v. Perrigo – construction of pharmacokinetic claim terms

Adams Respiratory Therapeutics, Inc. v. Perrigo Company (Fed. Cir., August 5, 2010)
Panel: Linn, Moore (author), Friedman

By Jason Rantanen

Adams holds patent number 5,372,252, which covers an extended release formulation containing guaifenesin (an expectorant used to thin, loosen, and help expel mucus that causes congestion).  Perigo sought FDA approval for a generic version of Adams' product, Mucinex®.  After construing the claims, the district court granted summary judgment of noninfringement.  Adams appealed that decision.

The claim terms in dispute related to pharmacokinetic parameters.  These parameters are used to characterize the rate and extent of absorption of the active pharmaceutical ingredient ("API").  The primary term at issue, Cmax, indicates the maximum concentration of the API following dosing.

"Equivalent Cmax"
The parties' main dispute was over the meaning of the term "equivalent" in the context of "provides a Cmax in a human subject equivalent to the Cmax obtained when the first of three doses of a standard immediate release formulation having one third the amount of guaifenesin is dosed."  For purposes of FDA approval, a formulation is considered to be bioequivalent if, among other things, its Cmax is within 80% to 125% of the value with which it is being compared at a 90% confidence interval. The district court agreed with Perrigo that "equivalent" should be construed to mean equivalent under the FDA bioequivalence guidelines.

On appeal, Adams challenged the requirement of a 90% confidence interval, arguing that it makes sense when seeking FDA approval, but not when proving infringement. 

The Federal Circuit agreed with Adams.  In doing so, it rejected Perrigo's argument that the inventors had expressly defined "equivalent" as te FDA's bioequivalence guidelines.  Rather, the court construed Adams' reference to the FDA guidelines as referring specifically to the 80-125% range, not to the requirement of a 90% confidence interval.  According to the court:

Requiring a 90% confidence interval would inappropriately raise the bar for establishing infringement.  Adams must show that it is more likely than not that Perrigo's ANDA product will have a Cmax within the 980-125% range. Adams is not required to show that Perrigo's product will meet this requirement 9 times out of 10.

Slip Op. at 8.

Comment: This interpretation opens up a box of statistical worms, and I suspect that down the line the court may regret its venture into probability theory.  For the time being, however, it gives parties useful language to quote when attempting to prove infringement (and perhaps invalidity) via clinical results. 

A ≈ B ≈ C therefore A ≈ C
Adams also appealed the district court's ruling that it  impermissibly compared the accused product to Mucinex.  Adams' argument was that because the accused product was bioequivalent to Mucinex, and Mucinex was bioequivalent to a standard immediate release ("IR") product, then the accused product had a Cmax equivalent to the IR product. 

The Federal Circuit agreed that, under the circumstances of this case, Adams' argument was sufficient to preclude summary judgment of noninfringement.  The court cautioned, however, that "[i]f Adams had relied on the mere fact of bioequivalence of the two sets of products (and no PK data or Cmax values, that would not be enough to survive summary judgment."  Slip Op. at 11.  Here, however, Adams presented actual PK data and Cmax values, which a fact-finder could look at when assessing equivalence between the accused product and an IR product. 

The court also addressed the meaning of the term "bioavailable" in the context of the '252 patent.  The dispute hinged on whether the phrase "fully bioavailable in the subject's stomach" meant "both release and availability in the stomach for absorption, wherever that absorption might occur." 

Perrigo argued that because "bioavailable" is commonly understood to mean absorption, thus requiring the guaifenesin to be absorbed in the stomach.  Because guaifenesin is primarily absorbed in the small intestine, this construction would preclude a finding of infringement.

The court rejected the proposed construction as inconsistent with the specification: "Although the specification never expressly defines bioavailable, it uses the term when describing the availability of the drug for absorption, not the actual absorption."  Slip Op. at 14.  The court further noted that Perrigo's construction would exclude the preferred embodiment, which "is rarely, if ever, correct and would require highly persuasive evidentiary support."

Doctrine of Equivalents
Finally, Adams argued that the district court erroneously precluded it from relying on the doctrine of equivalents with respect to a dependant claim requiring that the total amount of guaifenesin released in to the patient be at least 3500 hr*ng/mL.  The panel concluded that the use of a numerical limit did not preclude Adams from arguing that an amount of 3494.38 hr*ng/mL was equivalent to 3500 hr*ng/mL. 

Doctrine of Equivalents at the Federal Circuit

By Dennis Crouch

When I wrote about the Doctrine of Equivalents (DOE) yesterday, I made a mental note that the Federal Circuit has not decided many DOE cases recently. To confirm this notion, I searched Westlaw for all Federal Circuit decisions that mention the “Doctrine of Equivalents.” Those results are presented below:



  • Of course, a decision's mention of the words "doctrine of equivalents" does not suggest that the appellate decision involved the DOE. However, the majority of these cases did at least involve allegations of infringement under the DOE.   
  • The rise in the late 1990’s and early 2000’s revolves around Festo.
  • For the past decade, the number of Federal Circuit patent infringement appeals has remained relatively steady.
  • To find the number of reported patent decisions, I searched Westlaw’s database of Federal Circuit decisions for the terms “patent /2 (infring! valid! invalid! obvious!)”.
  • These results continue the trends discussed in Allison & Lemley’s 2007 article “The (Unnoticed) Demise of the Doctrine of Equivalents.” and Lee Petherbridge’s excellent 2008 article “The Claim Construction Effect.”

Genus-Species; Doctrine of Equivalents; and Patentable Subject Matter

By Dennis Crouch

For many, the most interesting aspect of this case comes at the end in Judge Dyk’s dissent. Dyk makes the case that genes should not be patentable. 

* * * *

Intervet Inc. v. Merial Limited (Fed. Cir. 2010)

In 2006, Intervet filed a complaint against Merial — asking the DC District Court for a declaratory judgment that Intervet’s Porcine Circovirus vaccine (PCV-2) did not infringe Merial’s gene patent.  Merial’s patent claims both the isolated DNA molecule of PCV-2 and a vector that contains the DNA.  The application includes a listing of several different sequences that all fall within the PCV-2 category. 

Although Intervet also uses a PCV-2 vector. The DJ plaintiff argues that its DNA molecule is different from the one described and deposited by Merial. The district court agreed — holding that the Intervet product was only 99.7% homologous to the closest deposited sequence and therefore outside of the literal claim scope. The district court also applied prosecution history estoppel to rejected Merial’s claims of infringement under the doctrine of equivalents (DOE). On appeal, the Federal Circuit reversed on both claim construction and DOE.

Genus Not Limited to Examples: The asserted claim includes a limitation of a “PCV-2” DNA molecule. The District Court limited that term to cover only the DNA sequences that were deposited with the PTO. On appeal, the Federal Circuit rejected that construction as overly limiting. Rather, the appellate panel held that the deposited sequences serve as a representative sample of PCV-2 DNA sequences. “Sequences are representative of the scope of broader genus claims if they indicate that the patentee has invented species sufficient to constitute the genera. Here, the deposited strains are representative species of the larger ‘type II’ genus, where the genus is identified and claimed as the invention.” In describing its invention, the specification noted that the PCV-2 desposited sequences had a 96% homology and that the invention did not cover PCV-1 sequences that at most shared 76% homology with the deposited sequences.  Taking those quantitative limits from the specification, the Federal Circuit ruled that the claimed PCV-2 molecule should be construed as being “about 96% or more homologous with the … sequences disclosed in the present specification, and about 76% or less homologous with the [disclosed PCV-1] sequence.”

What is Equivalents are Surrendered by a Narrowing Amendment: An accused infringer may still be liable even though its product does not literally infringe every element of an asserted patent claim.  Under the doctrine of equivalents (DOE), a patentee may be able to provie infringement by showing that one or more elements of the accused product are equivalent to elements in the claim.  Under the limiting doctrine of prosecution history estoppel (PHE), a patentee will ordinarly be estopped from claiming DOE over a claim element that was narrowed during prosecution. (A narrowing amendment made for purposes related to patentability creates a rebuttable presumption that estoppel applies.)

Here, one of Merial’s original claims was directed to a markush group of open reading frames (ORFs) that had been described in the specification as “ORFs 1–13.”  In an initial rejection, the examiner suggested that the limitation could refer to ORFs of non-PCV-2 molecules. Although the patentee argued that the claim was clear, it still added the limitation that the claimed ORFs were PCV-2 ORFs.  The Federal Circuit held that this was a narrowing amendment substantially related to patentability. That narrowing amendment therefore created a presumption that the patentee had surrendered all equivalents that relate to non-PCV-2 ORFs. The district court erred, however, in holding that this narrowing amendment would estopp the the patentee from asserting that the claims cover a non-claimed PCV-2 ORF as an equivalent. “Such a draconian preclusion would be beyond a fair interpretation of what was surrendered. The rationale for the amendment was to narrow the claimed universe of ORFs down to those of PCV-2, and bore only a tangential relation to the question of which DNA sequences are and are not properly characterized as PCV-2.”

Dissenting-in-part, Judge Dyk discussed his argument that the claims directed toward the isolated form of a naturally occurring gene are likely unpatentable under 35 U.S.C. § 101.

[T]he isolated DNA claim raises “substantial issues of patentable subject matter under 35 U.S.C. § 101. . . . Neither the Supreme Court nor this court has directly decided the issue of the patentability of isolated DNA molecules. Although we have upheld the validity of several gene patents, none of our cases directly addresses the question of whether such patents encompass patentable subject matter under 35 U.S.C. § 101. . . .

I think that such patents do in fact raise serious questions of patentable subject matter. The Supreme Court’s recent decision in Bilski v. Kappos has reaffirmed that “laws of nature, physical phenomena, and abstract ideas” are not patentable. No. 08-964, slip op. at 5 (U.S. June 28, 2010) (quoting Diamond v. Chakrabarty, 447 U.S. 303, 309 (1980)); Funk Bros. Seed Co. v. Kalo Inoculant Co., 333 U.S. 127, 130 (1948). Just as the patentability of abstract ideas would preempt others from using ideas that are in the public domain, see Bilski, slip op. at 13, so too would allowing the patenting of naturally occurring substances preempt the use by others of substances that should be freely available to the public. Thus, “a new mineral discovered in the earth or a new plant found in the wild is not patentable subject matter. Likewise, Einstein could not patent his celebrated law that E=mc2; nor could Newton have patented the law of gravity.” Chakrabarty, 447 U.S. at 309. These aspects are properly conceptualized as representing a public domain, “free toall men and reserved exclusively to none.” Id. (quoting Funk Bros., 333 U.S. at 130) (quotation mark omitted).

In Funk Brothers, the Court considered the patentability of a mixture of several naturally-occurring species of bacteria. 333 U.S. at 128-31. The patented product was a mixture of bacteria used in agricultural processes, enabling plants to draw nitrogen from the air and convert it for usage. The inventor discovered that certain strains of the bacteria were effective in combination with one another, and contrary to existing assump-tions, did not exert mutually inhibitive effects on each other. The Court held that the invention was not pat-entable subject matter. Id. at 131. The inventor “did not create a state of inhibition or of non-inhibition in the bacteria. Their qualities are the work of nature. Those qualities are of course not patentable.” Id. at 130. The Court furthermore noted:

The qualities of these bacteria, like the heat of the sun, electricity, or the qualities of metals, are part of the storehouse of knowledge of all men. They are manifestations of laws of nature, free to all men and reserved exclusively to none. He who discovers a hitherto unknown phenomenon of na-ture has no claim to a monopoly of it which the law recognizes. If there is to be invention from such a discovery, it must come from the applica-tion of the law of nature to a new and useful end.


In Chakrabarty, the Court considered whether a human-made microorganism is patentable subject matter under section 101. 447 U.S. at 305. The microorganism in question was a bacterium that had been genetically engineered to break down crude oil. In concluding that the man-made bacteria was patentable, the Court observed that the claim “is not to a hitherto unknown natural phenomenon, but to a nonnaturally occurring manufacture or composition of matter.” Id. at 309. The Court went on to distinguish Funk Brothers on the ground that the Chakrabarty bacterium possessed “markedly different characteristics from any found in nature. . . . His discovery is not nature’s handiwork, but his own; accordingly it is patentable subject matter under § 101.” Id. at 310 (em-phasis added).

Thus, it appears that in order for a product of nature to satisfy section 101, it must be qualitatively different from the product occurring in nature, with “markedly different characteristics from any found in nature.” It is far from clear that an “isolated” DNA sequence is qualita-tively different from the product occurring in nature such that it would pass the test laid out in Funk Brothers and Chakrabarty. The mere fact that such a DNA molecule does not occur in isolated form in nature does not, by itself, answer the question. It would be difficult to argue, for instance, that one could patent the leaves of a plant merely because the leaves do not occur in nature in their isolated form.



Narrowing Amendment and Prosecution History Estoppel

Felix v. American Honda (Fed. Cir. 2009)

Mr. Felix sued Honda for infringement of his patent covering a truck bed with a storage compartment underneath the bed. The Honda Ridgeline advertises a “lockable In-Bed Trunk®” that appears to serve the same overall purpose. The problem is that Felix’s asserted claim is rather narrow and the district court found no literal infringement and no infringement under the doctrine of equivalents. Asserted claim 6 reads as follows:

6. In combination with a vehicle including a vehicle bed, the improvement of a storage system which includes: a) an opening formed in the vehicle bed and including an opening rim; b) a compartment with an interior; c) said compartment being mounted on said bed with said compartment interior accessible through said opening; d) a lid assembly including lid mounting means for mounting said lid in covering relation with respect to said opening; e) a channel formed at the rim of said bed opening and including an inner flange; f) a weathertight gasket mounted on said flange and engaging said lid in its closed position; and g) a plurality of drain holes formed in said channel.

In particular, the accused Honda truck bed has a “weathertight gasket” mounted on the lid rather than to the flange as claimed in the Felix patent.

On appeal, the Federal Circuit affirmed the lower court’s judgment of non-infringement – finding Honda did not literally infringe and that Felix’s claim under the doctrine of equivalents (DOE) was foreclosed by prosecution history estoppel. Here, I will discuss the DOE dispute.

Doctrine of Equivalents: The patent claims spell out the boundaries of an inventor’s claimed invention. However, courts may extend the scope of exclusionary rights beyond the literal claim language to capture equivalent products. In recent years, the doctrine of equivalents has been limited. This case, the doctrine of prosecution history estoppel came into play because Felix had narrowed his claims prosecution. (Actually, the applicant cancelled the broad independent claims and re-wrote the dependent claims into independent form. Under Honeywell, that process has the same estoppel effect as narrowing the independent claim.)

Tangential: The presumption of estoppel can be overcome with evidence that the reason for the narrowing amendment is no more than tangentially related to the equivalent in question. The evidentiary standard for proving the “no more than tangential relationship” is quite high. Here, Felix offered a credible alternative explanation, but the Federal Circuit rejected his argument because (1) he did not prove that his alternative was “the only reason” for the amendment and (2) he did not “explain the entire amendment.”

“Because we conclude that Felix is barred by the doctrine of prosecution history estoppel from relying on the doctrine of equivalents to prove that the accused In-Bed Trunk meets the gasket limitation, we also affirm the district court’s summary judgment of no infringement by equivalents.”

Drafting Strategies: One interesting aspect of this case is that Felix had to go through a couple of rounds of amendments. After first amending to add the gasket, Felix then had to amend again to secure allowance. Although the first amendment did not directly lead to allowance, the narrowing amendment still created a presumption of estoppel:

“The fact that the first amendment did not succeed and that a further amendment was required to place the claim in allowable form, however, is of no consequence as to the estoppel. It is the patentee’s response to a rejection—not the examiner’s ultimate allowance of a claim—that gives rise to prosecution history estoppel.

We therefore hold that the presumption of prosecution history estoppel attaches when a patentee cancels an independent claim and rewrites a dependent claim in independent form for reasons related to patentability, even if the amendment alone does not succeed in placing the claim in condition for allowance.”

Judge Linn also pointed to an “open question” in footnote 4:

“We leave open the question of whether the presumption of surrender would have attached as to the gasket limitation if, in response to the first office action, Felix had cancelled both claim 1 and claim 7, and had rewritten claim 8 in independent form, instead of attempting to secure the broader coverage of rewritten claim 7 as an intermediate step.”

[Corrected 3:40 CST]


Improper Summary Judgment on Doctrine of Equivalents; Marking Products that Perform Method Claims

Crown Packaging v. Rexam Beverage Can (Fed. Cir. 2009)

On summary judgment, the district court held that Rexam did not infringe Crown’s patent beverage can-top patent. The lower court also found that that Crown did not infringe Rexam’s beverage can “necking” patent. On appeal, the Federal Circuit reversed both rulings.

The Doctrine of Equivalents: Over the past two decades, the doctrine of equivalents been pushed out of the usual infringement discussion. Part of the doctrine’s downgrade is due to restricted application due to prosecution history estoppel (Festo) and tighter doctrine (Warner-Jenkinson). Perhaps equally important in the decline of the DOE has been the rise of claim construction as the primary variable of patent litigation. Rather than arguing for infringement as an equivalent, applicants are instead arguing for broad construction of the claim terms. Finally, patent drafters are – on average – better today than they were twenty years ago and spend more energy on considering how to draft claims that capture literal infringement. In a 2007 paper, Professors Lemley and Allison found something similar – that since the late 1990’s (even before Festo), that “equivalents claims usually failed, most often on summary judgment.” Their paper title – “Demise of the Doctrine of Equivalents” – overstates its case. The DOE is sometimes valuable.

Function-Way-Result Test: There are at least two alternate tests for infringement under the doctrine of equivalents. The function-way-result test considers “on a limitation by limitation basis” whether “the accused product performs substantially the same function in substantially the same way with substantially the same result as each claim limitation of the patented product.”

Summary Judgment on DOE: Here, the issue was not so much the law of the DOE, but rather the requirement for summary judgment that there be no remaining material issue of fact. Crown’s patent claims an “annular reinforcing bead,” while Rexam’s product uses a reinforcing fold. The lower court found those different enough to avoid infringement under the DOE. On appeal, however, the Federal Circuit reversed – finding at least one unresolved material issue of fact that precluded summary judgment. DOE requires expert testimony to step through the function-way-result test. And, here, the patentee’s expert stepped through each element and his testimony had not been completely indicted or even refuted.

Because Crown provided evidence in support of its position that the annular reinforcing bead of claim 14 of the ‘826 patent had only one function, and because we must resolve any reasonable factual inferences in favor of the nonmoving party, we conclude that there is a material issue of fact regarding the function of the claimed bead. Accordingly, we reverse and remand the district court’s grant of summary judgment of noninfringement.

This decision by Judge Moore is in line with the court’s 2008 Voda case which was affirmed after parsing expert testimony to ensure that the elements had been properly proven. (In Voda, the court used the alternative “insubstantial difference” test.)

Unmarked Sales by Licensee: In a scenario reminiscent of the recent Quanta v. LG case, Rexam licensed its patents to Belvac to make “neckers” used to stretch out the top of the can bodies. Under the license, Belvac was required “to notify its customers that they would require a separate license from Rexam to perform the smooth die necking method” that is claimed in Rexam’s patents. The license did not require Belvac to mark the machines that it sold. And, in fact, Belvac did not mark them with the Rexam patent number. Crown then used the machine to make over one hundred billion cans.

Marking under 35 U.S.C. § 287(a): The district court found that this past infringement was not actionable because Crown was not on notice of the patent. That decision seemingly follows from 35 U.S.C. § 287(a). Under that provision, a patentee who does not properly mark a patented article “is not entitled to damages for infringement prior to actual notice.” (quoting CAFC decision).

Marking of Method Claims: Rexam’s trick here was to assert only method claims. On its face, Section 287 applies to “any patented article,” and Federal Circuit precedent has clearly stated that the marking requirement does not apply when only method claims are asserted. With palpable regret, Judge Moore writes:

“The law is clear that the notice provisions of § 287 do not apply where the patent is directed to a process or method. Bandag, Inc. v. Gerrard Tire Co., 704 F.2d 1578, 1581 (Fed. Cir. 1983). In Hanson, 718 F.2d 1075 (Fed. Cir. 1983)—we held that 35 U.S.C. § 287(a) did not apply where the patentee only asserted the method claims of a patent which included both method and apparatus claims. Hanson is factually identical to this case, and we are therefore bound by the rule of Hanson.”

Thus the patentee is free to claim damages back six years under Section 286 even without marking or providing actual notice. This decision thus provides an additional reason to include method claims in a patent application. Now, it would be improper to conclude that there is no reason to mark products that perform method claims. In the 1993 American Medical Systems case, the Federal Circuit ruled that marking would be required if “both apparatus and method claims” were asserted and there is a “tangible item to mark.” In this case, the patent claimed both a method and apparatus, but Rexam sued only on the method claims.

CAFC Finally Affirms a Finding of Infringement by Equivalents

PatentLawPic391Dr. Voda v. Cordis Corp. (Fed. Cir. 2008)

Dr. Voda’s case is an exciting tale of an individual inventor litigating against a major corporation in the red sandy soil of western Oklahoma. 

A jury found that Cordis catheters infringed Voda’s patents and adjudged a reasonable royalty to be 7.5% of gross sales. The jury also found the infringement willful and the patents not invalid.  The district court then affirmed the jury verdict but denied Voda’s request for injunctive relief.

Claim Construction: Voda’s claim included the requirement that the catheter be engaged “along a line” of the aorta. The district court, however, found that the claim is not limited to linear portions of the aorta. On appeal, the CAFC confirmed the construction — reminding us that “the context in which a term is used in the asserted claim can be highly instructive.” Phillips. When engaged, it is clear that the catheter may curve along the aorta.

The specification does indicate that the “present invention [includes a] straight portion.” However, the CAFC refused to see that statement as a “clear disavowal of claim scope” because the specification discusses other instances where the same portion could be curved.

Doctrine of Equivalents: Cordis had redesigned some of its products to avoid literal infringement. However, these were found to infringe under the Doctrine of Equivalents. In particular, a “second straight portion” claim element was not literally found in the Cordis products, but the jury found that the products did include an equivalent element.

At the court’s option, either of two tests of equivalent may be used:

Under the insubstantial differences test, “[a]n element in the accused device is equivalent to a claim limitation if the only differences between the two are insubstantial.” Honeywell Int’l Inc. v. Hamilton Sundstrand Corp., 370 F.3d 1131, 1139 (Fed. Cir 2004). Alternatively, under the function-way-result test, an element in the accused device is equivalent to a claim limitation if it “performs substantially the same function in substantially the same way to obtain substantially the same result.” Schoell v. Regal Marine Indus., Inc., 247 F.3d 1202, 1209-10 (Fed. Cir. 2001).

The CAFC looked to Voda’s experts to find evidence of insubstantial difference. In particular, Voda’s expert testified that the Cordis “curve portion” was essentially straight and that “cardiologists would have difficulty distinguishing the two during use.”  In addition, Voda introduced evidence that the Cordis curve portion “performed the same function as a straight portion, in the same way, to achieve the same result. . . . Accordingly, we affirm the jury’s findings of infringement with respect to these claims.”


  • EBay: Voda argued for an injunction based on the irreparable harm to its exclusive licensee. The CAFC rejected that justification — finding that the irreparably harmed must be the party seeking the injunction.
  • Seagate: The CAFC vacated the willfulness finding that was based on pre-Seagate law.
  • Festo: The CAFC did find that some of Voda’s claims were not infringed under the DOA. Those claims had been narrowed during prosecution and were subject to prosecution history estoppel.
  • Prior Appeal: In the 2007 appeal in this case, the CAFC held that Voda could not assert its foreign patents covering the same product in US courts. [LINK]


Prison: The last stand for land line phones.

TIP Systems v. Phillips & Brooks (PBG) (Fed. Cir. 2008)

“This is a patent infringement case pertaining to wall-mounted telephones designed for use by prison inmates.”  Both the accused device and the patents focus on a telephone system that operates without the dangers of a phone cord. However, the TIP patents require a “handset” mounted in the wall of the phone box with a mouthpiece that “extends through” the wall.  These claims are exemplified in the figures.

The accused devices do not use a traditional handset, but rather use a separate ear-piece and mouthpiece. In addition, the accused device wall is flush – and the mouthpiece does not break through the wall.

Questionable claims of infringement are naturally resolved by a Markman hearing and subsequent summary judgment of noninfringement. Here, the district court found (i) that the claimed handset must include a handle with both an ear-piece and mouthpiece and (ii) that the mouthpiece must pass through an aperture in the front wall of the phone box.  It was clear that the accused device did not exhibit either of these features and thus could not infringe.

The definition of the handset was made easy because the claims stated that: “a telephone handset being a handle with an ear-piece at one end and a mouthpiece at an opposite end.” The exact definition is support from the figures is also provided in the specification.

The CAFC affirmed on claim construction then went on to consider whether the elements may still be covered under the doctrine of equivalents (DOE). 

If an element is not literally covered by a claim, the device may still be considered infringing if the accused element is equivalent to the claimed element. Thus, to infringe a patent, each claim element or its equivalent must be found in an accused device.

Whether equivalency exists may be determined based on the “insubstantial differences” test or based on the “triple identity” test, namely, whether the element of the accused device “performs substantially the same function in substantially the same way to obtain the same result.” 

The game in the doctrine of equivalents is defining an ‘element.’  The patentee wants a broad definition (the telephones as a whole are very similar) while the defendant argues for a narrow definition. Here, the defendants won when the courts found that a “handle” is an element of the claim.  Since the accused devices have no structure that is similar to a handle, they cannot infringe even as an equivalent.


Continued Vitiation of The Doctrine of Equivalents

Wleklinski (dba Comfort Strapp) v. Targus (Fed. Cir. 2007) (Non-Precedential).

PatentLawPic128In March, 2007, the Central District of California dismissed Comfort Strapp’s complaint on summary judgment — finding no proof of infringement.  Comfort Strapp’s patent relates to a comfortable shoulder strap for luggage.

The fight was over the construction of an “auxiliary strap means” limitation that requires the strap’s end sections be “made of a relatively non-stretchable material” and the strap’s center section be “made of [stretchable] material.”  Because the Targus auxiliary strap was made of a single material, the CAFC agreed that it could not literally infringe.

Doctrine of Equivalents: Accused products that exhibit only ‘insubstantial differences’ from the claimed patent may also be considered infringing under the doctrine of equivalents. (DOE). However, the DOE cannot apply where it would vitiate a claim limitation.

Here, the Federal Circuit panel agreed that as a matter of law, the doctrine of equivalents does not allow a claimed two-material strap to encompass a strap made of only one material. According to the appellate panel, such a reading would be “the fundamental opposite of the claimed invention.” Citing Freedman Seating.

Notes: Although the court’s trend to limit the doctrine of equivalents began well before the Supreme Court’s KSR ruling. The bulked-up nonobviousness test naturally reduces the scope of the doctrine of equivalents as the DOE cannot extend to cover variations that would have been obvious at the time of patenting.

CAFC: Meaning of “About”

UltracetOrtho-McNeil Pharm. v. Caraco Pharm. (Fed. Cir. 2006).

Ortho’s patent covers a pain-relief combo of tramadol and acetaminophen with a ratio of “about 1:5.” Caraco’s drug has a ratio of 1:8.67.  The lower court construed the claims and found no infringement.

Claim Construction: On appeal, the Federal Circuit construed the term “about 1:5” by first looking at the intrinsic evidence.  In the patent and claims, Ortho had used the term “about” repeatedly: disclosed ratios included about 1:1, about 1:5, about 1:19 to about 1:5, and about 1:1600. 

The court reasoned that the term must have a narrow meaning in this patent because a broad meaning would leave other claimed ratios meaningless. The court also noted that the literal meaning of the term should be narrowly construed because Ortho “could have easily claimed a [broader] range of ratios”

An expert testified that the statistical range should be 1:3.6 to 1:7.1 based on a confidence interval constructed from the data in the patent, and the Federal Circuit agreed. (The patent discussed the importance of 95% CI).

Literal Infringement: The Federal Circuit found that there could be no literal infringement because the upper claimed bound for the ratio was 1:7.1 while Caraco’s ratio was 1:8.67.

Doctrine of Equivalents: No DOE because Ortho cancelled claims with broader range during reissue. Interestingly, the Court made this ruling based on vitiation rather than prosecution history estoppel:

[I]t cancelled the broader “comprising” claims, except for claim 6. In sum, having so distinctly claimed the “about 1:5” ratio, Ortho cannot now argue that the parameter is broad enough to encompass, through the doctrine of equivalents, ratios outside of the confidence intervals expressly identified in the patent. We agree with the district court that to do so would eviscerate the limitation.

Summary judgment of noninfringement affirmed

Even under DOE, “predetermined” combo must be determined beforehand

BingoPlanet Bingo v. Gametech (Fed. Cir. 2006).

Planet Bingo is the exclusive licensee of two patents covering a way to play bingo.  This game combines the numbers with an indicator (such as the color red) to give enhanced awards. The patent claims a “predetermined” winning combination, and that is where the dispute lies.

In the accused game of “rainbow bingo,” the color of the first ball chosen serves as the indicator.  Since that color is not known before the game begins, the court found it was not “predetermined.” as required by the claims.

Planet Bingo, however, asserted infringement under the DOE. Although the defendant’s indicator color is not known before the game begins, it is known immediately after the first bingo ball is drawn — something that is equivalent.  The CAFC disagreed, finding that under Warner-Jenkinson, a color that is “predetermined” cannot, as a matter of law, be equivalent to a color that is selected immediately after the game starts.

Here, the court focused particular attention on foreseeability of the asserted equivalent — apparently assuming that most variations in the bingo-arts would be foreseeable.