• BASICS: If an accused system/process does not literally meet a claim element, but has an equivalent thereto, there may be infringement under the Doctrine of Equivalents (DOE). Equivalents analysis is applied to each claim element separately, not to claim as a whole. Warner-Jenkinson (U.S. 03/03/1997) (unanimous). Equivalents is evaluated from perspective of a person having ordinary skill in the art (PHOSITA) at time of the alleged infringement, and intent is irrelevant. Warner-Jenkinson (U.S. 03/03/1997) (“If the essential predicate of the doctrine of equivalents is the notion of identity between a patented invention and its equivalent, there is no basis for treating an infringing equivalent any differently from a device that infringes the express terms of the patent. Application of the doctrine of equivalents, therefore, is akin to determining literal infringement, and neither requires proof of intent.”).
  • Formulation: “This court applies two articulations of the test for equivalence. 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.’ 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.’” Voda (Fed. Cir. 08/18/08) (aff’g jury verdict of equivalents infringement). One DOE formulation is whether the claim element and accused structure/step perform substantially the same claim-recited function (Applied Med. (Fed. Cir. 05/15/06)) in substantially the same way, to achieve substantially the same result. Graver Tank (U.S. 05/29/1950) (aff’g equivalents infringement where accused welding-flux composition used silicate of manganese instead of claim-recited silicate of an alkaline earth metal, but prior art and experts showed that manganese silicates had been used in welding fluxes and the two were substantially identical in operation and result.); Machine Co. (U.S. 1878); Tomita II (Fed. Cir. 03/17/17) (non-precedential) (aff’g judgment of no structural equivalence to means-plus-function element). “An analysis of the role played by each element in the context of the specific patent claim will … inform the inquiry as to whether a substitute element matches the function, way, and result of the claimed element, or whether the substitute element plays a role substantially different from the claimed element.” Warner-Jenkinson (U.S. 03/03/1997); Intendis (Fed. Cir. 05/16/16) (aff’g finding of DOE infmt.: accused isopropyl myristate performed substantially the same function as the claimed triglyceride and lecithin); VirnetX (Fed. Cir. 09/16/14) (rev’g jury verdict of DOE; security here not equivalent to encryption). Spec. may or may not evidence the claim element’s function, way or result, in the claimed composition, and court may look to understanding of a skilled artisan (here, the defendant’s representations to the FDA in its ANDA). Intendis (Fed. Cir. 05/16/16). The substantial differences test may be more appropriate for non-mechanical cases than the function-way-result test, because “a compound may appear to be equivalent under the FWR test, but not under the substantiality of the differences test.” Mylan (Fed. Cir. 05/19/17) (comparing both tests in analyzing whether silver oxide and manganese dioxide are “equivalent” in patents claiming methods for preparing a chemical compound, and noting that when compounds are expressly named in claims, “an infringement analysis must not take lightly [their] specific recitation.” “The Supreme Court was surely correct in stating that non-mechanical cases may not be well-suited to consideration under the FWR test. That seems to be particularly true in the chemical arts.”)).
  • Interchangeability At Time Of Infringement May Evidence Equivalency: The known interchangeability between claimed and accused elements at the time of infringement (not when the patent was issued), can be strong evidence of equivalency. Graver Tank (U.S. 05/29/1950).
  • Equivalent To PHOSITA: Failure to show equivalents from perspective of PHOSITA entitled accused to JMOL of no infringement. Lighting World (Fed. Cir. 09/03/04).
  • Changing Order Of Steps May Be Equivalent, or Not: Cadence Pharm. (Fed. Cir. 03/23/15) (aff’g DOE infringement where claimed method first dissolved an active ingredient to form a solution and then deoxygenated the solution, whereas accused process first deoxygenates a solvent and only then adds an active ingredient.); Wi-LAN (Fed. Cir. 01/08/16) (changed order of processing led to mathematically identical result but saved 20 transistors out of a few hundred for relevant functionality, which is substantial evidence for jury verdict of no DOE.)
  • Patent On Accused Device Does Not Increase Doctrine Of Equivalents Burden To Clear And Convincing Evidence: Siemens Med. (Fed. Cir. 02/24/11), rehearing denied (Fed. Cir. 06/07/11) (with opinions).

a) required evidence

  • Patentee Must Provide Particularized Testimony And Linking Argument: “A patentee must…provide particularized testimony [“of a person of ordinary skill in the art, typically a qualified expert”] and linking argument as to the ‘insubstantiality of the differences’ between the claimed invention and the accused device or process, or with respect to the function, way, result test when such evidence is presented to support a finding of infringement under the doctrine of equivalents. Such evidence must be presented on a limitation-by-limitation basis. Generalized testimony as to the overall similarity between the claims and the accused infringer’s product or process will not suffice.” Aquatex Indus. (Fed. Cir. 02/27/07) (aff’g Summ. J. of no DOE where patent owner submitted only lawyer argument and deposition testimony on how product worked); Advanced Steel (Fed. Cir. 11/12/15) (aff’g Summ. J. of no DOE where expert’s “substantially the same way” analysis pointed to satisfaction of only other claim elements); Paice (Fed. Cir. 10/18/07) (testimony sufficient); Amgen (Fed. Cir. 09/15/09) (evidence insufficient); Eastcott (Fed. Cir. 06/04/14) (non-precedential) (aff’g Summ. J. of no DOE where affidavit conclusory); Gemalto (Fed. Cir. 06/19/14) (aff’g Summ. J of no DOE where testimony not particularized); but see WCM Indus. (Fed. Cir. 02/05/18) (non-precedential) (rev’g JMOL that had overturned jury verdict finding redesigned product infringing under DOE; there is no requirement for opinion testimony for a finding of equivalence, and in special circumstances it is proper to compare redesigned product to infringing original product).
  • Intrinsic Evidence Is Primary Source Of Evidence Of Function-Way-Result: To determine the function, way, result of a claimed element, look to the claim and the patent, but if they are silent, look to evidence from those skilled in the art (e.g., as to advantages of the accused design). Stumbo (Fed. Cir. 11/28/07).

b) matter of law restrictions

  • Several Matter Of Law Restrictions On Doctrine Of Equivalents: There are several “matter of law” legal restrictions on DOE, making this defense ripe for Summ. J., including:
    • Spec. Disavows Alleged Equivalent: DOE may not recapture subject matter disavowed in the written description. AstraZeneca (Fed. Cir. 09/30/04); Paice (Fed. Cir. 10/18/07) (finding no disavowal in patent’s criticism of the prior art); Cordis (Fed. Cir. 01/07/08) (finding no disavowal in PH’s explicit definition of meaning of a claim term, that was already implied in the patent); Rembrandt Patent (Fed. Cir. 11/22/17) (non-precedential) (aff’g no DOE infringement; DOE cannot recapture what Spec. gave up (i.e., manual initiation of recovery process)); Lexion (Fed. Cir. 08/28/08) (non-precedential) (finding no PHE disclaimer because “disputed statements in the prosecution history are subject to multiple reasonable interpretations, they do not constitute the clear and unmistakable surrender required to trigger prosecution disclaimer.”); Sunbeam Prod. (Fed. Cir. 12/15/10) (“The specification . . . explains what is not the claimed invention, and because that explanation excludes the accused bearings from falling within the reach of the patent, those devices cannot infringe under the doctrine of equivalents.”) (non-precedential).
    • Claim (As Construed) Specifically Excludes Alleged Equivalent: DOE may not capture what claim (or its construction) “specifically excludes.” “Specific exclusion” bars DOE “where the patentee seeks to encompass a structural feature that is the opposite of, or inconsistent with, the recited limitation.” Augme Tech. (Fed. Cir. 06/20/14) (linked code in Web page cannot be substantially same as “embedded code” because construction of “embedded code” specifically excludes linked code; aff’g Summ. J. of no DOE); Enzo III (Fed. Cir. 08/02/17) (non-precedential) (aff’g Summ. J. of no equivalents infringement by “direct” detection based on earlier panel’s construction expressly excluding direct detection from scope of claim); Southco (Fed. Cir. 04/10/15) (non-precedential) (parts not directly attached cannot be equivalent to claimed structure requiring direct attachment, as that is “the very thing that the construction excludes.”); Decisioning (Fed. Cir. 05/07/08) (“Decisioning is precluded from asserting that those systems infringe under the doctrine of equivalents, as doing so would vitiate an element of the claims — i.e., ‘remote interface’ as construed.”); Dolly (Fed. Cir. 02/08/94) (rev’g equivalents infringement decision; “the concept of equivalency cannot embrace a structure that is specifically excluded from the scope of the claims.”)
    • Alleged Equivalent Would Vitiate Claim Element (As Construed): DOE may not effectively eliminate (vitiate) any claim element in its entirety. Hilton Davis II (Fed. Cir. 06/12/97) (en banc) (no vitiation); Power Integrations (Fed. Cir. 12/12/16) (rev’g jury verdict of equivalents; finding a single feedback signal equivalent to claimed two “distinct” feedback signals would vitiate that element where it was the alleged improvement over the prior art); Trading Techs. (Fed. Cir. 02/25/10) (“this rule empowers a court to perform again the standard ‘insubstantial variation’ test for equivalency, but this time as a question of law. Claim vitiation applies when there is a ‘clear, substantial difference or a difference in kind’ between the claim limitation and the accused product.”); Akzo Nobel (Fed. Cir. 01/29/16) (vitiation applies if equivalence theory “renders a claim limitation inconsequential or ineffective”); Impulse Tech. (Fed. Cir. 12/07/16) (non-precedential) (“The accused hardcoded values, which are abstract, mathematical constructs coding for a physical space that is known only after adaptation of the system, and the claimed “defined physical space,” known prior to adaptation of the system, are essentially the antithesis of one another. Thus, no reasonable jury could conclude that they are equivalents.”). Cf. Deere & Co. (Fed. Cir. 12/04/12) (“Courts should be cautious not to shortcut this inquiry by identifying a ‘binary’ choice in which an element is either present or ‘not present.’”); Epos Tech. (Fed. Cir. 09/05/14) (same). There is no separate vitiation exception to DOE. Brilliant Instruments (Fed. Cir. 02/20/13) (2-1) (rev’g Summ. J. of no equivalents (based on vitiation theory); vitiation is merely a finding of no equivalents); accord Warsaw I(Fed. Cir. 03/02/15) (aff’g jury verdict of DOE: “jury could find that two enclosing prongs capable of lateral movement and pivoting was equivalent to three enclosing prongs, two of which were capable of lateral movement and pivoting”); Charles Machine (Fed. Cir. 07/26/13). But see Cadence Pharm. (Fed. Cir. 03/23/15) (aff’g DOE infringement; “‘Vitiation’ is not an exception or threshold determination that forecloses resort to the doctrine of equivalents, but is instead a legal conclusion of a lack of equivalence based on the evidence presented and the theory of equivalence asserted”; citing many cases for this).
    • Prosecution History Estoppel (see below).
    • Public Dedication (see below).
    • Ensnarement Of Prior Art (Wilson Sporting Goods) (i.e., scope sought to be reached under DOE, viewed as a hypothetical claim, must be patentable). Legal question for court. Jang (Fed. Cir. 09/29/17). Detailed, post-KSR analysis aff’g trial court finding that DOE hypothetical claim did not ensnare the prior art. Depuy Spine (Fed. Cir. 06/01/09). “An accused infringer seeking to avoid infringement under the doctrine of equivalents on this basis bears the burden of ‘presenting prior art which shows that the asserted range of equivalence would encompass the prior art,” but the patentee bears the ultimate burden of persuasion to show that its claims do not cover the prior art.” Energy Transport (Fed. Cir. 10/12/12); Jang (Fed. Cir. 09/29/17) (aff’g non-equivalents based on ensnarement; patent owner failed its burden to prove patentability of hypothetical claim by failing to present hypothetical claim broader in all respects than actual claim. Hypothetical claim may not be narrower in any respect. Court is not obligated to draft proper hypothetical claim.). But see Gemalto (Fed. Cir. 06/19/14) (aff’g Summ. J. of no DOE where proposed scope of DOE would ensnare prior art microprocessors). “Hypothetical claims extend the actual claim to literally recite the accused product.” Intendis (Fed. Cir. 05/16/16) (aff’g finding of DOE and rejecting defendant’s proposed hypothetical claim as too broad). Hypothetical claim may not narrow the actual claim in any respect. Streamfeeder (Fed. Cir. 04/20/99). “The hypothetical claim analysis is not the only method in which a district court can assess whether a doctrine of equivalents theory ensnares the prior art.” Jang (Fed. Cir. 09/29/17). See generally IPLaw 360 article (10/24/17) (discussing Jang and ensnarement doctrine).
    • Literal Claim Already Captures Equivalents: Qualitative measures (e.g., “about”) may bar DOE. In context of this patent, word “about” before a numerical limitation “brought what would otherwise be equivalents of a limitation into the literal scope of the claim, [so] the doctrine of equivalents is unavailable to further broaden the scope of the claim.” Cohesive Tech. (Fed. Cir. 10/07/08); cf. Adams Respiratory (Fed. Cir. 08/05/10) (doctrine of equivalents may apply to numerical ranges, even those stating “at least __.”); Pozen (Fed. Cir. 09/28/12) (aff’g DOE infringement; although “substantially all” is qualitative, its construction based on the Spec. was quantitative (“at least 90%”) so DOE available, and 85% level infringed under DOE).
  • That accused feature was foreseeable at the time of the application is not a bar on DOE. Ring & Pinion (Fed. Cir. 02/19/14). Legal restrictions on DOE are for the Court to decide (e.g., on Summ. J. or JMOL) not the jury, even if have underlying factual inquiries and need to consider expert testimony and other evidence. Depuy Spine (Fed. Cir. 06/01/09) (ensnarement issue).

c) prosecution history estoppel

  • BASICS: Legal question for court. Jang (Fed. Cir. 09/29/17). Actions before the PTO might bar the patent owner from using DOE to capture the accused technology. The issue normally is whether an amendment (voluntary or not) or argument surrendered originally claimed subject matter, for reasons related to patentability. Argument-based estoppel arises when the applicant makes an argument evincing a “clear and unmistakable surrender” of subject matter. Spectrum Pharm. (Fed. Cir. 10/02/15). “To determine whether prosecution-history estoppel applies, ‘the relevant inquiry is whether a competitor would reasonably believe that the applicant surrendered the relevant subject matter.’” Power Integrations (Fed. Cir. 09/20/18). The standard “Festo” (Festo (U.S. 05/28/2002) (unanimous), Festo (Fed. Cir. 09/26/03) (en banc)) analysis for amendments is as follows:
    • first, did the amendment narrow the literal scope of a claim? Cf. EMD Millipore (Fed. Cir. 09/29/14) (finding PHE; amendment broadened and narrowed, creating presumption of estoppel).
    • if yes, and no reason is stated in the prosecution history (PH) for the narrowing amendment, there is a rebuttable presumption that it was made for a substantial reason related to patentability, and thus PHE applies. Cf. Warner-Jenkinson (U.S. 03/03/1997) (“place the burden on the patent holder to establish the reason for an amendment required during patent prosecution”)
      • to overcome this presumption, the patent owner can rely solely on evidence in the PH record
    • if estoppel applies, there is a rebuttable presumption that PHE completely bars application of DOE as to amended claim limitations (i.e., that all territory between the original claim limitation and the amended claim limitation is off limits for DOE (Norian (Fed. Cir. 12/06/05)).
      • the patent owner may show, however, that it did not surrender the particular equivalent in question by showing that at the time of the amendment, one skilled in the art could not reasonably have been expected to draft a claim that literally encompassed the alleged equivalent.
      • this may be established by showing that: (1) the alleged equivalent would have been “unforeseeable” at the time of the claim amendment; (2) the objective rationale (as shown in the prosecution history) underlying the amendment bore no more than a “tangential relation” to the alleged equivalent; or (3) there was “some other reason” (e.g., shortcomings of language) why the patentee could not reasonably be expected to have literally claimed the alleged equivalent. This third “excuse” may not be used if the alleged equivalent was in the prior art. See Honeywell (Fed. Cir. 04/18/08) (extended discussion of foreseeability and tangential relation, rejecting both and upholding JMOL no infringement); Integrated Tech. I (Fed. Cir. 11/04/13) (PH estoppel not rebutted).
      • this rebuttal-of-presumption issue presents a question of law for the Court.
  • Claim Preamble Defines Field Of Invention For Foreseeability Analysis: where claim recited “Pharmaceutical compositions … comprising conjugated estrogens …,” the alleged equivalent “need only to have been known in the field of pharmaceutical compositions” not that it be known to be suitable for use with conjugated estrogens. Duramed Pharm. (Fed. Cir. 07/21/11).
  • Bar May Arise From Rewriting “Objected To” Dependent Claims: Narrowing may be found from cancelling a broad claim: “the rewriting of dependent claims into independent form coupled with the cancellation of the original independent claims creates a presumption of prosecution history estoppel.” Honeywell (Fed. Cir. 06/02/04) (en banc); Felix (Fed. Cir. 04/10/09).
  • If Presented As Separate Arguments, Each Distinction Over Prior Art (In PTO) Forms Its Own Estoppel: PODS (Fed. Cir. 04/27/07).
  • Presumption Of Estoppel Attaches Even If Amendment Unsuccessful: Felix (Fed. Cir. 04/10/09).
  • Bar Rebutted Because Amendment Tangential To Equivalent: Festo bar rebutted where rationale underlying the narrowing amendment bears “no more than a tangential relation to the equivalent in question.” Insituform (Fed. Cir. 10/04/04); Dakocytomation Calif. (Fed. Cir. 02/28/08) (rev’g Summ. J., finding presumption rebutted under tangential relation argument); Funai (Fed. Cir. 09/01/10) (aff’g that claim term merely tangential to prosecution).
  •  May Arise From Prosecution Of Parent ApplicationPower Integrations (Fed. Cir. 09/20/18) (aff’g refusal to find prosecution history estoppel from arguments in parent prosecution where language of claims differed.)
    • TIPS:

d) disclosure-dedication restriction

  • BASICS: There are several ways in which a patent (or its expiration) may dedicate subject matter to the public, immunizing it from a charge of patent infringement, or from a charge of “equivalents” infringement.
  • Disclosure Of Alternative To Claimed Feature Or Embodiment Bars DOE Reaching The Alternative (“Disclosure-Dedication Doctrine”): A patent disclosing an embodiment or feature (as being in the prior art and/or as being an embodiment of the “invention”) without claiming it precludes coverage of that feature under DOE, even if claimed in a continuation. Johnson & Johnston (Fed. Cir. 03/28/02) (en banc) (but can be claimed in a continuation patent); Ottah (Fed. Cir. 03/07/18) (aff’g R. 12(b)(6) dismissal of pro se complaint under Iqbal / Twombly; partly because Spec. described “book holder” holding book or camera but claim recites holding book, equivalents infringement not plausible against a mobile camera); CSP Tech. (Fed. Cir. 03/22/16) (non-precedential) (aff’g Summ. J. of no DOE, after first limiting claim to one of two embodiments, holding that disclosure of unclaimed second embodiment barred DOE, noting that continuation patent omitted the narrowing claim term); PSC (Fed. Cir. 01/20/04) (“Because PSC dedicated plastic clips to the public by explicitly claiming only clips made of metal while specifically disclosing that the prior art included clips made of plastic, we affirm [Summ. J. of non-infringement].”); Zircon (Fed. Cir. 10/05/11) (non-precedential) (Spec. disclosed two embodiments; claims recited first and defendant used second; Summ. J. of no infringement affirmed). Intent not to claim the disclosed alternative is irrelevant; and issue is a matter of law. Toro (Fed. Cir. 09/13/04). Also applies to disclosure of (unclaimed) alternative in a priority application that was omitted from the patent’s application. Abbott Labs. (Fed. Cir. 05/18/09). But, disclosure must expressly or implicitly identify unclaimed embodiment as alternative to claimed embodiment. CSP Tech. (Fed. Cir. 03/22/16) (non-precedential); SanDisk (Fed. Cir. 10/09/12) (rev’g trial court disclosure-dedication based judgment of no DOE as to two claim limitations: the alternative must be disclosed with specificity and the patent must identify it as an alternative to the claimed approach).
  • Disclosure Dedication Extends to Subject Matter Disclosed As Prior Art: PSC (Fed. Cir. 01/20/04): includes subject matter disclosed as prior art, but not claimed.
    • TIPS:

e) relationship to sec. 112(6/f)

  • DOE vs. Sec. 112(6/f) Structural Equivalents: Comparison of Sec. 112(6/f) structural equivalents to DOE equivalents, explained: Frank’s Casing (Fed. Cir. 11/30/04); and in Minks (Fed. Cir. 10/17/08). Sec. 112(6/f) equivalents evaluated as of time of issuance; DOE equivalence evaluated at time of infringement; and Sec. 112(6/f) equivalents requires same function; DOE allows equivalent function. Ring & Pinion (Fed. Cir. 02/19/14) (no foreseeability exception applies to DOE for a means-plus-function element or any other element).
  • DOE On Sec. 112(6/f) Element: Aff’g no infringement where accused product’s function not equivalent to function in means plus function element. Pennwalt (Fed. Cir. 11/06/87) (en banc) (must perform identical function).
    • TIPS: