Court Opinion

ID: 4643975
Source: CourtListenerOpinion
Date Created: 2020-12-17 16:00:42.626297+00
Date Added: 2024-06-11T08:00:42.879093
License: Public Domain

Case: 20-1387    Document: 54    Page: 1   Filed: 12/17/2020

        NOTE: This disposition is nonprecedential.

   United States Court of Appeals
       for the Federal Circuit
                  ______________________

            BRACCO DIAGNOSTICS INC.,
                 Plaintiff-Appellee

                            v.

          MAIA PHARMACEUTICALS, INC.,
                Defendant-Appellant
               ______________________

                        2020-1387
                  ______________________

     Appeal from the United States District Court for the
 District of New Jersey in No. 3:17-cv-13151-PGS-TJB, Sen-
 ior Judge Peter G. Sheridan.
                   ______________________

                Decided: December 17, 2020
                  ______________________

     WILLIAM R. ZIMMERMAN, Knobbe, Martens, Olson &
 Bear, LLP, Washington, DC, argued for defendant-appel-
 lant. Also represented by THOMAS P. KRZEMINSKI, KAREN
 MARIE CASSIDY, Irvine, CA.

    DONALD RHOADS, Rhoads Legal Group PC, New York,
 NY, argued for plaintiff-appellee. Also represented by H.
 DANNY KAO, Kao & Associates, Pc, Flushing, NY.
                 ______________________
Case: 20-1387    Document: 54      Page: 2   Filed: 12/17/2020

2     BRACCO DIAGNOSTICS INC.   v. MAIA PHARMACEUTICALS, INC.

    Before LOURIE, CLEVENGER, and CHEN, Circuit Judges.
 LOURIE, Circuit Judge.
      Maia Pharmaceuticals, Inc. (“Maia”) appeals from a
 judgment of the United States District Court for the Dis-
 trict of New Jersey that Maia’s sincalide product infringes
 U.S. Patent 6,803,046 (“the ’046 patent”), owned by Bracco
 Diagnostics, Inc. (“Bracco”). J.A. 1–8. The court entered
 the judgment pursuant to a stipulation of infringement by
 the parties in view of the court’s claim construction of the
 terms buffer, surfactant/solubilizer, and surfactant.
 Bracco Diagnostics, Inc. v. Maia Pharms., Inc., No. 3:17-cv-
 13151, 2019 WL 4885888 (D.N.J. Oct. 3, 2019) (“Claim
 Construction Order”). Because Maia stipulated to infringe-
 ment under a claim construction that is essentially correct,
 we affirm.
                        BACKGROUND
     This appeal concerns a patent infringement action
 brought by Bracco under the Hatch-Waxman Act. Bracco
 owns the ’046 patent, listed in the Food and Drug Admin-
 istration’s (FDA) Orange Book as covering Kinevac®, the
 active ingredient of which is sincalide. The ’046 patent has
 claims directed to sincalide formulations, methods for mak-
 ing and using sincalide formulations, and sincalide powder
 kits. ’046 patent col. 37 l. 40–col. 44 l. 30. Sincalide, a
 synthetic peptide hormone, is typically administered to
 stimulate gallbladder contraction, stimulate pancreatic se-
 cretion, and accelerate the transit of a barium meal
 through the small bowel. J.A. 79–80, 191; ’046 patent col.
 13 ll. 40–58. Although sincalide was originally introduced
 in 1976, the ’046 patent purports to teach sincalide formu-
 lations that are “purer than prior art formulations, and
 have fewer degradants and more consistent potency” in
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 BRACCO DIAGNOSTICS INC.   v. MAIA PHARMACEUTICALS, INC.      3

 part through addition of excipients 1 such as buffers, sur-
 factants/solubilizers, and surfactants. ’046 patent col. 1 ll.
 9–26, 46–49. All 36 claims at issue in this litigation require
 sincalide, a buffer, and, depending on the claim, either a
 surfactant/solubilizer or a surfactant. Id. col. 37 l. 40–col.
 40 l. 44.
      In 2017, Maia filed a New Drug Application (“NDA”)
 for its own sincalide product pursuant to FDCA § 505(b)(2).
 It is undisputed that Maia’s sincalide product contains
 amino acid excipients. Maia certified pursuant to §
 505(b)(2)(A)(iv) that its sincalide product would not in-
 fringe the ’046 patent claims. Bracco filed suit in December
 2017, alleging that Maia’s product does infringe the claims.
 Maia denied infringement, asserting that the amino acid
 excipients in its sincalide product do not act as buffers, sur-
 factants/solubilizers, or surfactants, as required by the
 claims. Maia also counterclaimed that the claims are inva-
 lid. The parties requested that the district court construe
 the terms buffer, surfactant/solubilizer, and surfactant.
 Central to the claim construction dispute was whether the
 three terms encompass amino acids.
     Claim 1 reads as follows:
         1. A stabilized, physiologically acceptable formula-
         tion of sincalide comprising:
             (a) an effective amount of sincalide,
             (b) at least one stabilizer,

    1  Although both parties reference “excipients” through-
 out their briefs, neither party defines the term. We accept
 the construction proposed by the district court: “An inac-
 tive substance that serves as the vehicle or medium for a
 drug or other active substance.” Claim Construction Order,
 2019 WL 4885888, at *2 n.1 (citing Oxford English Diction-
 ary).
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4     BRACCO DIAGNOSTICS INC.   v. MAIA PHARMACEUTICALS, INC.

             (c) a surfactant/solubilizer
             (d) a chelator,
             (e) a bulking agent/tonicity adjuster, and
             (f) a buffer.
 ’046 patent col. 37 ll. 41–49 (emphases added).
     Several dependent claims contain “Markush” groups
 that further recite that buffers or surfactants/solubilizers
 can be selected from a list of excipients that includes amino
 acids. A Markush group “lists alternative species or ele-
 ments that can be selected as part of the claimed inven-
 tion.” Multilayer Stretch Cling Film Holdings, Inc. v. Berry
 Plastics Corp., 831 F.3d 1350, 1357 (Fed. Cir. 2016) (citing
 Abbott Labs. v. Baxter Pharm. Prods., Inc., 334 F.3d 1274,
 1280 (Fed. Cir. 2003)).
    Claim 3 depends from claim 1, and recites that an
 amino acid can be selected as a buffer:
     3. The formulation of claim 1, wherein said buffer
     is selected from the group consisting of . . . one or
     more amino acids . . . and biological buffers.
 ’046 patent col. 37 ll. 51–60 (emphases added).
    Claim 6 depends from claim 1 and recites that an
 amino acid can be selected as a surfactant/solubilizer:
     6. The formulation of claim 1, wherein said surfac-
     tant/solubilizer is selected from the group consist-
     ing of . . . amino acids.
Id. col. 37 l. 65–col. 38 l. 5 (emphases added).
     Claim 40 is to a kit, where a powder mixture contains
 a surfactant:
     40. A kit, comprising:
         (i) a powder mixture comprising
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 BRACCO DIAGNOSTICS INC.     v. MAIA PHARMACEUTICALS, INC.   5

             (a) sincalide,
             (b) at least one stabilizer,
             (c) a surfactant,
             (d) a chelator,
             (e) a bulking agent/tonicity ad-
             juster, and
             (f) a buffer;
         (ii) a container to hold said powder mix-
         ture; and
         (iii) optionally, a physiologically acceptable
         fluid.
Id. col. 39 ll. 53–62 (emphasis added).
    Claim 44 depends from claim 40 and recites that an
 amino acid can be selected as a surfactant:
     44. The kit of claim 40, wherein said surfactant is
     selected from the group consisting of . . . amino ac-
     ids.
Id. col. 40 ll. 10–18 (emphases added).
     The specification provides further context regarding
 the meaning of the three terms. For example, the specifi-
 cation explains that buffers “are employed to stabilize the
 pH of sincalide formulations of the invention, and conse-
 quently, reduce the risk of chemical stability 2 at extreme
 pH values.” Id. col. 9 ll. 45–47. The specification provides
 a nonexclusive list of buffering agents “useful in the prep-
 aration of formulation kits,” which includes amino acids.
Id. col. 9 ll. 48–65. The list of exemplary buffering agents
 in the specification is substantially similar to the buffering

     2   We presume that this is a typographical error and
 the patentee intended to write “instability.”
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6     BRACCO DIAGNOSTICS INC.    v. MAIA PHARMACEUTICALS, INC.

 agents listed in the dependent claims for buffer. See, e.g.,
 id. col. 37 ll. 51–60.
      The specification also includes a section entitled “Sur-
 factants/Solubilizers/Surface Active Agents,” which ex-
 plains that “[t]he addition of a nonionic surfactant . . . may
 reduce the interfacial tension or aid in solubilization thus
 preventing or reducing denaturation and/or degradation at
 air/liquid or liquid/solid interfaces of the product in solu-
 tion.” Id. col. 11 ll. 26–34. The specification further pro-
 vides      two     non-exclusive        exemplary  lists    of
 surfactants/solubilizers, which include amino acids. Id.
 col. 11 ll. 35–63. The lists of exemplary surfactants/solu-
 bilizers in the specification overlap with the dependent
 claims for surfactants/solubilizers and surfactants. E.g.,
 id. col. 37 l. 65–col. 38 l. 5, col. 40 ll. 11–18.
    With respect to the term buffer, the district court
 adopted the following construction:
     An excipient that: stabilizes the pH of sincalide for-
     mulations of the invention, and consequently, re-
     duces the risk of chemical stability at extreme pH
     values. Buffering agents useful in the preparation
     of formulation kits of the invention include phos-
     phoric acid, phosphate (e.g. monobasic or dibasic
     sodium phosphate, monobasic or dibasic potassium
     phosphate, etc.), citric acid, citrate (e.g. sodium cit-
     rate, etc.), sulfosalicylate, acetic acid, acetate (e.g.
     potassium acetate, sodium acetate, etc.), methyl
     boronic acid, boronate, disodium succinate hexahy-
     drate, amino acids, including amino acid salts
     (such as histidine, glycine, lysine, imidazole), lactic
     acid, lactate (e.g. sodium lactate, etc.), maleic acid,
     maleate, potassium chloride, benzoic acid, sodium
     benzoate, carbonic acid, carbonate (e.g. sodium car-
     bonate, etc.), bicarbonate (e.g. sodium bicarbonate,
     etc.), boric acid, sodium borate, sodium chloride,
     succinic acid, succinate (e.g. sodium succinate),
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 BRACCO DIAGNOSTICS INC.   v. MAIA PHARMACEUTICALS, INC.       7

     tartaric acid, tartrate (e.g. sodium tartrate, etc.),
     tris(hydroxymethyl) aminomethane, biological
     buffers (such as N-2-hydroxyethylpiperazine, N’-2-
     ethanesulfonic acid (HEPES), CHAPS and other
     ‘Good’s’ buffers).
 Claim Construction Order, 2019 WL 4885888, at *10 (em-
 phasis added). The district court thus imported into its def-
 inition the list of exemplary buffering agents from the
 specification. It rejected Maia’s proposal to construe the
 term buffer to mean “[a] compound that stabilizes the pH
 of a sincalide formulation.” Id. at *3.
      The district court construed the term surfactant/solu-
 bilizer to mean:
     A surfactant and/or a solubilizer. The addition of a
     nonionic surfactant, such as polysorbate, to the for-
     mulation, may reduce the interfacial tension or aid
     in solubilization thus preventing or reducing dena-
     turation and/or degradation at air/liquid or liq-
     uid/solid interfaces of the product in solution.
     Surfactants/solubilizers include compounds such
     as free fatty acids, esters of fatty acids with polyox-
     yalkylene compounds like polyoxypropylene glycol
     and polyoxyethylene glycol; ethers of fatty alcohols
     with polyoxyalkylene glycols; esters of fatty acids
     with polyoxyalkylated sorbitan; soaps; glycerol-pol-
     yalkylene stearate; glycerol polyoxyethylene ricino-
     leate; mono- and copolymers of polyalkylene
     glycols; polyethoxylated soya-oil and castor oil as
     well as hydrogenated derivatives; ethers and esters
     of sucrose or other carbohydrates with fatty acids.
     Fatty alcohols, these being optionally polyoxyalkyl-
     ated; mono-, di-, and triglycerides of saturated or
     unsaturated fatty acids; glycerides or soya-oil and
     sucrose; sodium caprolate, ammonium sulfate, so-
     dium dodecyl sulfate (SDS), Triton-l00 and anionic
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8     BRACCO DIAGNOSTICS INC.   v. MAIA PHARMACEUTICALS, INC.

     surfactants containing alkyl, aryl or heterocyclic
     structures.
     Examples of preferred surfactants/solubilizers for
     use in the present invention include, but are not
     limited to, pluronics (e.g., Lutrol F68, Lutrol F
     127), Poloxamers, SDS, Triton-100, polysorbates
     such as TWEEN® 20 and TWEEN® 80, propylene
     glycol, PEG and similar compounds, Brij58 (poly-
     oxyethylene 20 cetyl ether), cremophor EL, cetyl
     trimethylammonium bromide (CTAB), dimethyla-
     cetamide (DMA), NP-40 (Nonidet p 40), and N-me-
     thyl-2-pyrrolidone (Pharmasolve), glycine and
     other amino acids/amino acid salts and anionic
     surfactants containing alkyl, aryl or heterocyclic
     structures, and cyclodextrins. TWEEN® 20 is the
     most preferred surfactant in formulations of the in-
     vention.
Id. at *10 (emphasis added). As it did with the term buffer,
 the court imported a list of preferred surfactants/solubil-
 izers from the specification into its definition of the term.
 It rejected Maia’s proposal to construe surfactant/solubil-
 izer to mean “[a] surfactant that is also a solubilizer. A
 solubilizer is a compound that aids in solubilization, thus
 preventing or reducing sincalide denaturation and/or deg-
 radation cause by peptide aggregation, precipitation, sur-
 face adsorption, or agitation at air/liquid or liquid/solid
 interfaces in solution.” Id. at *2.
     Lastly, the district court construed the term surfactant
 to mean “[a]n excipient that may reduce the interfacial ten-
 sion.” Id. at *10 (emphasis added). The court rejected
 Maia’s proposal to construe surfactant to mean “[a] com-
 pound that reduces the tension of the air/liquid or liq-
 uid/solid interface.” Id. at *5. The court also rejected
 Bracco’s proposal to import a list of exemplary surfac-
 tants/solubilizers from the specification into its definition.
Id. at *7.
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 BRACCO DIAGNOSTICS INC.   v. MAIA PHARMACEUTICALS, INC.    9

     In view of the district court’s claim constructions, the
 parties stipulated to infringement of claims 1–3, 6, 10–17,
 19, 21–23, 26, 30–37, 40–41, 44, and 48–55 (“the stipulated
 claims”) and dismissal of the remaining claims and de-
 fenses without prejudice. J.A. 1–8, 3666–3678. The court
 made no evidentiary findings regarding infringement in its
 final judgment. Maia appealed to this court. We have ju-
 risdiction over the appeal pursuant to 28 U.S.C. 1295(a)(1).
                         DISCUSSION
     Maia argues that we should vacate the district court’s
 construction of the terms buffer, surfactant/solubilizer, and
 surfactant, adopt Maia’s proposed constructions for the
 terms, and remand to the district court for further proceed-
 ings. At issue in this dispute is whether the district court
 erroneously included amino acids in its definitions of buffer
 and surfactant/solubilizer, erroneously construed the back-
 slash between surfactant/solubilizer to mean “and” or “or,”
 and erroneously included “may” in its definition of surfac-
 tant.
     Claim construction is a question of law that we review
 de novo. Teva Pharm. USA, Inc. v. Sandoz, Inc., 135 S. Ct.
831, 839 (2015). We review de novo the district court’s find-
 ings of fact on evidence “intrinsic to the patent (the patent
 claims and specifications, along with the patent’s prosecu-
 tion history),” and review for clear error underlying fact
 findings related to extrinsic evidence. Id. at 841.
     As an initial matter, we note that the district court did
 not specify in its claim construction order which claims it
 was construing. Claim Construction Order, 2019 WL
4885888, at *10. However, that does not matter here, as
 we are dealing with the same claim limitations in all of the
 claims, and can readily review their constructions.
     In order to resolve the disputes, we turn to the claim
 language of the stipulated claims. See Phillips v. AWH
 Corp., 415 F.3d 1303, 1314 (Fed. Cir. 2005) (en banc). Both
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 10   BRACCO DIAGNOSTICS INC.    v. MAIA PHARMACEUTICALS, INC.

 the dependent and independent claims recite the disputed
 terms buffer, surfactant/solubilizer, or surfactant. The
 scope of the dependent claims is expressly defined by nam-
 ing the intended components, through Markush claiming.
 For example, dependent claims 3, 23, and 41 recite that a
 “buffer is selected from the group consisting of a [list of ex-
 cipients, including amino acids].” ’046 patent col. 37 ll. 51–
 60, col. 38 ll. 58–67, col. 39 l. 63–col. 40 l. 5. The dependent
 claims that recite a surfactant and a surfactant/solubilizer
 are substantially similar. See, e.g., id. col. 39 ll. 5–12
 (“[S]urfactant/solubilizer is selected from the group con-
 sisting of . . . .”), col. 41 ll. 5–12 (“[S]urfactant is selected
 from the group consisting of . . . .”). The Markush groups
 are “closed” because “[u]se of the transitional phrase ‘con-
 sisting of’ to set off a patent claim element” indicates that
 the claim “exclude[s] any elements, steps, or ingredients
 not specified in the claim.” Multilayer, 831 F.3d at 1358
 (quoting AFG Indus., Inc. v. Cardinal IG Co., 239 F.3d
1239, 1245 (Fed. Cir. 2001)). Thus, the dependent claims
 need no formal construction because, through the Markush
 claim drafting, the possible components are named and the
 scope of the dependent claims is thus definite and clear.
      The independent claims also recite use of buffers, sur-
 factants/solubilizers, and surfactants in sincalide formula-
 tions, methods of making sincalide formulations, and
 sincalide kits. See, e.g., ’046 patent col. 37 ll. 41–49, col. 38
 ll. 51–55, col. 39 ll. 53–62. However, unlike the dependent
 claims, the scope of the independent claims is not expressly
 defined by naming the possible components. We will there-
 fore construe the district court’s claim constructions as ap-
 plicable to the disputed independent claims.
                            I. Buffer
       Maia argues that the district court wrongly imported
 a list of exemplary buffers from the specification into its
 definition of the term buffer. Maia asserts that the plain
 and ordinary meaning of buffer within the context of the
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 BRACCO DIAGNOSTICS INC.   v. MAIA PHARMACEUTICALS, INC.    11

 patent specification is functional: “a compound 3 that stabi-
 lizes the pH of a sincalide formulation.” Appellant Br. at
 43–44 (emphasis added); see also ’046 patent col. 9 ll. 45–
 47 (“Buffering agents are employed to stabilize the pH of
 sincalide formulations of the invention . . . .”) (emphasis
 added). According to Maia, the court eliminated the func-
 tional aspect of buffer by construing it to include excipients
 such as amino acids that do not necessarily have buffering
 effects. Maia asserts that the court’s broad construction of
 buffer is contrary to its plain and ordinary meaning.
     Maia emphasizes that its amino acids do not have buff-
 ering effects. It asserts, however, that because the district
 court defined buffer broadly to necessarily include all
 amino acids, even those that do not actually act as buffers,
 it had no choice but to stipulate to infringement. Maia ef-
 fectively interprets the court’s construction to mean: an ex-
 cipient that stabilizes the pH of a sincalide formulation and
 consequently, reduces the risk of chemical [in]stability at
 extreme pH values or [all amino acids regardless of func-
 tion]. Appellant Rep. Br. at 22. In other words, Maia does
 not consider the stipulation to be an admission that its
 amino acids actually function to stabilize the pH of a sin-
 calide formulation. Rather, the stipulation is only an ad-
 mission that Maia’s product has amino acids. Maia thus
 argues that if this court removes the “predetermined” list
 of excipients, which includes amino acids, from the defini-
 tion of buffer, we would need to remand the case for an in-
 fringement analysis as to whether Maia’s amino acids have
 buffering effects.
     Bracco responds that the district court properly defined
 buffer to include a list of excipients from the specification.

     3    Maia’s proposed construction refers to a buffer as a
 compound. Appellant Br. at 43–44. The court construed
 buffer to be an “excipient.” According to Maia, the distinc-
 tion is not material to the case. Appellant Rep. Br. at 16.
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 12   BRACCO DIAGNOSTICS INC.    v. MAIA PHARMACEUTICALS, INC.

 Bracco first argues that the specification provides a list of
 excipients, including amino acids, that the “inventors used
 to define” buffer, and therefore the list must be included in
 the definition of buffer. Appellee Br. at 27 (citing ’046 pa-
 tent col. 9 ll. 45–65). Bracco also points to dependent
 claims, like claim 3, which recite that “a buffer is selected
 from the group consisting of” a substantially similar list of
 exemplary buffers as those listed in the specification. Ap-
 pellee Br. at 27.
      According to Bracco, any error in claim construction is
 harmless. It rejects Maia’s argument that it only stipu-
 lated to having amino acids in its product, not that its
 amino acids have buffering effects. Bracco asserts that
 Maia is misconstruing the district court’s construction of
 the three terms in the stipulation “as somehow reading out
 the functions required by the terms.” Appellee Br. at 16.
 Bracco states that when Maia stipulated to infringement,
 Maia effectively agreed that “each of [its] two amino acids
 is a ‘buffer’ excipient with a ‘buffer’ effect, which is [a]n ex-
 cipient that: stabilizes the pH of sincalide formulations . . .
 .” Id. at 16–17. Bracco thus argues that the court’s re-
 moval of the exemplary list has no effect on the infringe-
 ment analysis. Maia is foreclosed, Bracco argues, from
 asserting that its amino acids do not have buffering effects
 in view of the stipulation. Bracco also asserts that extrinsic
 evidence demonstrates that Maia’s amino acids function as
 buffers. However, Bracco does not cite any portion of the
 claim construction order or final judgment demonstrating
 that the court took into account evidentiary findings re-
 garding the function of Maia’s amino acids.
     We agree with Maia that the district court technically
 erred in importing a list of excipients into its definition of
 buffer. Listing numerous compounds that meet the lan-
 guage of a functional term in a claim confuses construing
 what the function is with what compounds perform that
 function. The latter is not the task of claim construction,
 which is to provide definitional meaning to claim language.
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 BRACCO DIAGNOSTICS INC.    v. MAIA PHARMACEUTICALS, INC.       13

 The court correctly did that when it stated that a buffer,
 for purposes of this invention, is “[a]n excipient that: stabi-
 lizes the pH of sincalide formulations of the invention, and
 consequently, reduces the risk of chemical [in]stability at
 extreme pH values.” Claim Construction Order, 2019 WL
4885888, at *10. That construction by the district court
 was correct, and the court’s technical error of then listing
 from the specification a long list of compounds meeting that
 meaning does not invalidate that functional construction.
 And claim 3 then recites that the buffer in claim 1 includes
 one or more amino acids. That technical error was thus
 harmless. Maia then stipulated to infringement.
     The key language of its stipulation reads as follows:
 “Under the Court’s construction of the disputed claim
 terms of the ’046 patent, . . . Maia’s 505(b)(2) NDA Product
 would literally infringe the 36 claims.” J.A. 3673; see also
 J.A. 5–6. That stipulation forecloses the argument for non-
 infringement.
      Maia argues that it had no choice but to stipulate to
 infringement because the district court’s construction re-
 moved the functional aspect of buffer and predetermined
 that Maia’s amino acids have buffering effects. But the dis-
 trict court did not “remove” the functional definition of
 buffer. The court correctly included the functional defini-
 tion in its claim construction. Maia asks us to effectively
 reinterpret the court’s construction to mean: an excipient
 that stabilizes the pH . . . buffering agents to include . . .
 [all amino acids regardless of function]. But that was not
 the stipulation.
      Maia also points to a “whereas” clause in the stipula-
 tion stating that “the [district court’s] construction, explic-
 itly defining ‘buffer’ . . . to include ‘amino acids,’ alone forms
 the basis for Maia’s admission and stipulation.” Appellant
 Rep. Br. at 23 (citing J.A. 3671) (emphasis added). But that
 is also not what the stipulation says, and we do not rely on
 a self-serving “whereas” clause to override the clear import
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 14   BRACCO DIAGNOSTICS INC.   v. MAIA PHARMACEUTICALS, INC.

 of the statement. That clause is directly contradictory to
 Maia’s admission in the other portion of the stipulation
 that its product meets “every element and claim term” of
 the claims. J.A. 3669. Moreover, even Maia admits that
 the “whereas” clause is neither binding nor conclusive. Ap-
 pellant Rep. Br. at 23.
      Maia similarly argued that the claims are invalid as
 inoperable, because, it asserts, amino acids are not buffers.
 However, it relinquished those arguments when it stipu-
 lated to infringement and dismissal of its counterclaims of
 invalidity. J.A. 6, 3673. Consequently, contrary to Maia’s
 assertion, it did have an opportunity to assert that its
 amino acids do not function as “buffering agents” because
 they do not “stabilize the pH.” To the extent that Maia be-
 lieved the district court’s construction had a particular
 meaning, it never sought clarification from the court, and
 that issue, in light of the stipulation, is now beyond the
 scope of this appeal. J.A. 3670. Having entered into a stip-
 ulation, Maia is now bound by it. See Inventio AG v. Otis
 Elevator Co., 497 F. App’x 37, 41 (Fed. Cir. 2012) (rejecting
 a party’s argument that it did not stipulate to a certain fact
 because the wording of the stipulation “suggests otherwise,
 and it is to that stipulation [the party] is bound”); United
 States v. Penland, 370 F. App’x 381, 383 (4th Cir. 2010) (re-
 jecting party’s attempt to disavow “unambiguous language
 set forth in the [s]tipulation”); United States v. Kieffer, 794
F.3d 850, 852 (7th Cir. 2015) (asserting that a party “may
 not disavow [its] stipulations by quibbling over seman-
 tics”).
      Because the district court’s claim construction is essen-
 tially correct and Maia stipulated to infringement if that
 were so, we affirm the judgment of infringement without
 remand. See, e.g., SUFI Network Servs., inc. v. United
 States, 755 F.3d 1305, 1312 (Fed. Cir. 2014) (remand can
 be unnecessary where “no further record development is
 appropriate”); Shinyei Corp. of Am. v. United States, 524
F.3d 1274, 1284 n.3 (Fed. Cir. 2008) (holding that “because
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 BRACCO DIAGNOSTICS INC.   v. MAIA PHARMACEUTICALS, INC.     15

 the issues on appeal are legal, not factual, we see no need
 to remand”).
                  II. Surfactant/Solubilizer
     We turn next to Maia’s argument that the district court
 erred in construing the term surfactant/solubilizer. Maia
 again argues here that the court wrongly imported a list of
 exemplary surfactants/solubilizers from the specification
 into the definition. Maia also argues that the court improp-
 erly construed the backslash between surfactant/solubil-
 izer to mean “and” or “or” rather than “and.” We address
 each argument in turn.
      With regard to the first issue, Maia argues that the dis-
 trict court “eviscerated” the functional aspect of the term
 surfactant/solubilizer by importing a list of exemplary ex-
 cipients into its definition regardless as to whether they ac-
 tually function as such. We agree with Maia that the
 district court technically erred in importing a list of excip-
 ients into its definition of surfactant/solubilizer. But, as
 with the term buffer, inclusion of the list of exemplary sur-
 factant/solubilizer agents, while technically incorrect, is es-
 sentially correct in its functional definition. As a result,
 the court’s technical error is harmless.
     Our analysis here is similar to our analysis regarding
 the district court’s error in construing buffer. The district
 court correctly included the functional definition in its
 claim construction. Its construction reads that a surfac-
 tant/solubilizer “may reduce the interfacial tension or aid
 in solubilization thus preventing or reducing denaturation
 and/or degradation at air/liquid or liquid/solid interfaces of
 the product in solution.” Claim Construction Order, 2019
WL 4885888, at *10. Inclusion of the sentence “the addi-
 tion of a nonionic surfactant, such as polysorbate,” along
 with an exemplary list of surfactant/solubilizer agents,
 does not invalidate the functional portion of the construc-
 tion. Moreover, as with buffer, claim 6 recites that the sur-
 factant/solubilizer includes amino acids. ’046 patent col. 37
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 16   BRACCO DIAGNOSTICS INC.   v. MAIA PHARMACEUTICALS, INC.

 l. 65–col. 38 l. 5. Maia’s product includes amino acids and
 thus it stipulated to infringement. When Maia stipulated
 to infringement under the court’s claim construction, it
 stipulated to infringing every limitation of the claims, not
 just to having amino acids. Having entered into a stipula-
 tion, Maia is bound by it.
      We now turn to Maia’s second argument. Maia argues
 that the district court wrongly construed surfactant/solu-
 bilizer to mean a surfactant “and” or “or” a solubilizer, ra-
 ther than a surfactant that is also a solubilizer. As support
 for its position, Maia argues that the specification sets
 forth a pattern of using a backslash to describe one excipi-
 ent that has multiple functions. For example, in Table 1,
 mannitol is reported to function as a “bulking agent/cake
 forming agent/tonicity adjuster.” ’046 patent cols. 3–4 Ta-
 ble 1. According to Maia, the table indicates that mannitol
 is a bulking agent [and] cake forming agent [and] tonicity
 adjuster. Appellant Br. at 34. Maia further argues that
 the district court’s construction of “surfactant/solubilizer”
 to mean a surfactant or solubilizer would allow the claims
 to encompass sincalide formulations without surfactants.
 According to Maia, that impermissibly broadens the scope
 of the claims beyond that supported by the specification be-
 cause every embodiment and description of the invention
 in the patent requires a surfactant. Maia points to Table 1
 and example 7, both of which include sincalide formula-
 tions comprising surfactants, and statements in the speci-
 fication that the formulation includes a surfactant.
     Bracco responds that the specification supports its con-
 struction of the backslash to mean “and” or “or.” With re-
 spect to Maia’s argument that the specification only
 discloses embodiments comprising surfactants, Bracco ar-
 gues that Maia attempts to impermissibly read preferred
 embodiments into the claim. It asserts that the patent’s
 disclosure contains no disclaimer of sincalide formulations
 without surfactants and that, on the contrary, there are
 several examples of formulations in the specification that
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 BRACCO DIAGNOSTICS INC.    v. MAIA PHARMACEUTICALS, INC.        17

 do not contain surfactants, including those described in ta-
 bles 8 and 9. With regard to Maia’s argument that the
 specification uses the backslash in Table 1 to define a sin-
 gle excipient that has more than one function, Bracco as-
 serts that the backslash could also be construed in that
 context to mean “or.” For example, in Table 1, mannitol
 can be a bulking agent [or] a cake forming agent [or] a to-
 nicity adjuster. Appellee Br. at 46.
       We agree with Bracco that the district court correctly
 construed the backslash in surfactant/solubilizer to mean
 “and” or “or.” Beginning with the claim language, the plain
 reading of the claims is that the backslash means “and” or
 “or.” Claim 1, in relevant part recites: “A stabilized, phys-
 iologically acceptable formulation of sincalide comprising:
 . . . (c) a surfactant/solubilizer . . . .” ’046 patent col. 37 ll.
 41–49 (emphasis added). Claim 7 depends from claim 1
 and recites: “The formulation of claim 1, wherein said sur-
 factant is a nonionic surfactant.” Id. col. 38 ll. 6–7 (empha-
 sis added). Dependent claim 7’s recitation of a formulation
 with only a surfactant lends credence to Bracco’s argument
 that the backslash can mean “or” and not necessarily “and.”
     We next turn to the specification. Maia argues that
 this specification requires a construction of the backslash
 to mean only “and.”             However, Maia’s argument is
 grounded solely on this specification’s ambiguous language
 and its disclosure of a few preferred embodiments of the
 patent that include sincalide formulations comprising sur-
 factants. For example, Maia argues that the specification
 sets forth a pattern of using a backslash when describing
 multiple functions performed by the same excipient, as ex-
 emplified by Table 1. However, as Bracco points out, the
 backslash in Table 1 can also be interpreted to mean “or.”
 Additionally, all of Maia’s quotes from the specification ref-
 erence a preferred embodiment. Appellant Br. at 35–36
 (quoting ’046 patent col 1 ll. 56–62 (“In one aspect, the in-
 vention features sincalide formulations that include . . . a
 surfactant . . . .”), col. 2 ll. 1–2 (“In various embodiments of
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 18   BRACCO DIAGNOSTICS INC.   v. MAIA PHARMACEUTICALS, INC.

 the invention, the surfactant is a nonionic surfactant . . .
 .”)) (emphases added). Maia omits that the specification’s
 disclosure that “[t]he sincalide formulations of the inven-
 tion can include a variety of excipients, such as, for[] exam-
 ple . . . surfactants,” indicates that surfactants are not
 necessary. ’046 patent col. 4 ll. 8–12 (emphases added).
 Here, although the specification discloses a few preferred
 embodiments of sincalide formulations with surfactants,
 Maia has not demonstrated that the patentee has a “clear
 intention to limit the claim scope.” Hill-Rom Servs., Inc. v.
 Stryker Corp., 755 F.3d 1367, 1372 (Fed. Cir. 2014).
     We thus conclude that the district court correctly con-
 strued the backslash in surfactant/solubilizer to mean
 “and” or “or.”
                        III. Surfactant
      Lastly, Maia argues that the district court erred in con-
 struing the term surfactant to mean “an excipient that may
 reduce the interfacial tension.” Maia asserts that in con-
 struing surfactant, the court improperly imported into the
 definition ambiguous and non-definitional language from
 the specification—“[t]he addition of a nonionic surfactant.
 . . may reduce the interfacial tension.” See ’046 patent col.
 11 ll. 27–34 (emphasis added). Maia argues that because
 every excipient “may” or “may not” reduce interfacial ten-
 sion, under the court’s construction, a surfactant encom-
 passes “every excipient in the universe,” including
 excipients that increase interfacial tension or are nonfunc-
 tional. Appellant Br. at 20. Maia argues that as a result,
 the court’s construction is contrary to the plain and ordi-
 nary meaning of the term.
     According to Maia, the plain and ordinary meaning of
 surfactant in view of the specification as a whole is a com-
 pound that “must” reduce the interfacial tension at the
 air/liquid or liquid/solid interfaces. Appellant Rep. Br. at
 18. As support for Maia’s narrower construction, it states
 that the only disclosed surfactant effect in the specification
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 is the reduction of interfacial tension at the air/liquid or
 liquid/solid interface rather than any increase in interfa-
 cial tension. Maia points to the specification’s disclosure
 that a nonionic surfactant may “reduce the interfacial ten-
 sion . . . at air/liquid or liquid/solid interfaces . . . .” See
 ’046 patent col. 11 ll. 27–34. (emphases added). Maia also
 points to Example 3 of the patent, entitled “Effect of Sur-
 factants on Sincalide Formulations,” to support its argu-
 ment. Example 3 states, in relevant part, that use of even
 trace amounts of a surfactant “still produced a significant
 effect on the air/liquid interface.” ’046 patent col. 22 ll. 28–
 30 (emphases added). Maia states that the “effect” refers
 to an increase in potency attributed to the surfactant’s re-
 duction of surface tension at the air/liquid interface. Maia
 further cites several dictionaries that define surfactant to
 mean an excipient that necessarily reduces interfacial ten-
 sion at the air/liquid or liquid/solid interface.
     Bracco responds that the district court’s construction is
 accurate in light of the specification’s explicit disclosure
 that a surfactant “may reduce the interfacial tension.”
 Bracco disagrees with Maia’s position that the court’s use
 of “may” in the definition renders the term meaningless.
 According to Bracco, a person of skill would interpret “may”
 to mean “capable of under certain circumstances.” Appel-
 lee Br. at 14. As support, Bracco cites expert testimony.
 Thus, Bracco argues that the court’s construction would in-
 clude only surfactants that can, or are capable of, reducing
 interfacial tension, but would not include “everything in
 the universe.” Id. at 13.
     Bracco also argues that Maia is improperly loading ad-
 ditional limitations onto the term from the specification by
 requiring that surfactant be construed as an excipient that
 must reduce interfacial tension at certain interfaces.
 Bracco contends that the patentee has made no clear and
 unmistakable disclaimer that the definition of surfactant
 should be limited in the manner that Maia proposes. With
 regard to Maia’s argument that the specification discloses
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 20   BRACCO DIAGNOSTICS INC.     v. MAIA PHARMACEUTICALS, INC.

 several statements and examples that surfactants reduce
 interfacial tension at the air/liquid or liquid/solid interface,
 Bracco responds that language referring to one preferred
 embodiment of a surfactant, does not so limit all surfac-
 tants. Id. at 39 (“[T]he addition of a nonionic surfactant,
 such as polysorbate, to the formulation, may reduce the in-
 terfacial tension . . . at air/liquid or liquid/solid interfaces.”
 (quoting ’046 patent col. 11 ll. 29–34)) (emphasis added).
     Bracco further contends that Maia misrepresents Ex-
 ample 3 as supporting its argument that the only surfac-
 tant effect disclosed in the patent is reduction of interfacial
 tension. According to Bracco, Maia purports to quote from
 Example 3’s disclosure that a nonionic surfactant “still pro-
 duced a significant effect on the air/liquid interface,” and
 misleadingly ascribes that “effect” to increase in potency
 resulting from a surfactant’s reduction of interfacial ten-
 sion, while cropping the next line, which actually explains
 that the effect was the elimination of “foaming in the for-
 mulation.” ’046 patent col. 22 ll. 28–31. Bracco addition-
 ally asserts that Maia’s requirement that surfactants
 function at the air/liquid or liquid/solid interface does not
 comport with claim 40, which is directed to a powder mix-
 ture kit that has no liquid present.
     With regard to the extrinsic evidence proffered by
 Maia, Bracco asserts that a person of ordinary skill, which
 Bracco contends is a peptide drug formulator, would not
 look to dictionaries to learn about the formulation of a pep-
 tide drug; according to Bracco, formulation of peptide drugs
 presents highly specialized technical issues and a diction-
 ary would not be of use to a skilled peptide formulator.
 Bracco points out that several of Maia’s dictionaries reject
 Maia’s narrow construction of “surfactant” in favor of de-
 fining it as “usually” effecting other properties and other
 interfaces. J.A. 587. Lastly, Bracco asserts that Maia’s
 construction does not take into account evidence that a per-
 son of skill would consider a surfactant to have other effects
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 BRACCO DIAGNOSTICS INC.   v. MAIA PHARMACEUTICALS, INC.     21

 including inhibition in aggregation, improvement in solu-
 bility, and reduction of adsorption.
      We agree with Bracco that the district court correctly
 construed the term surfactant. First, contrary to Maia’s
 assertion, the court’s use of the word “may” in its construc-
 tion does not render surfactant meaningless. We agree
 with Maia that “may,” standing alone, presents some am-
 biguity. However, the plain and ordinary meaning of “may”
 within the context of this specification is properly under-
 stood as indicating an inherent measure of likelihood or
 possibility. It is not used by a person of skill to describe an
 event that has no likelihood of occurring. For example, the
 specification discloses that “[t]he addition of a nonionic sur-
 factant . . . may reduce the interfacial tension” and contin-
 ues to provide an exemplary list of surfactants/solubilizers.
 ’046 patent col. 11 ll. 26–63 (emphasis added). It is unlikely
 that the patentee intended to provide an exemplary list of
 surfactants/solubilizers that could never be capable of re-
 ducing interfacial tension. Even Maia acknowledges that
 “may” encompasses possibility or probability in its brief.
 Appellant Br. at 19 (“It is undisputed that the term ‘may’
 is permissive, used to indicate possibility.”). It follows that
 the district court’s definition includes excipients that re-
 duce interfacial tension, or are capable of reducing interfa-
 cial tension, but excludes excipients that can never reduce
 interfacial tension. Thus, the term is not meaningless, as
 Maia alleges.
      We further disagree with Maia’s argument that the
 specification expressly indicates that surfactants must re-
 duce interfacial tension at the air/liquid or liquid/solid in-
 terface. First, the specification’s disclosure that one type
 of surfactant “may reduce the interfacial tension,” supports
 the district court’s construction that surfactants need not
 necessarily reduce interfacial tension. ’046 patent col. 11
 ll. 29–34 (emphasis added). Maia recites a few lines from
 the description section and from a preferred embodiment
 as support for its limitation. However, none of Maia’s
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 22   BRACCO DIAGNOSTICS INC.   v. MAIA PHARMACEUTICALS, INC.

 references indicates that the patentee intended to limit the
 claim scope in the manner that it asserts. For example,
 Maia argues that Example 3 demonstrates that the pur-
 pose of surfactants is to increase potency through reduction
 of interfacial tension, although Bracco rightly points out
 that the “effect” could be referring to foaming. Id. col. 22
 ll. 28–31. We have repeatedly “cautioned against limiting
 the claimed invention to preferred embodiments or specific
 examples in the specification,” where, like here, the pa-
 tentee has not made a clear disavowal of the claim scope.
 Imaginal Systematic, LLC v. Leggett & Platt, Inc., 805 F.3d
1102, 1109–10 (Fed. Cir. 2015) (quoting Williamson v. Cit-
 rix Online, LLC, 792 F.3d 1339, 1346–47 (Fed. Cir. 2015));
 see also Ericsson, Inc. v. D-Link Sys. Inc., 773 F.3d 1201,
 1218 (Fed. Cir. 2014) (“[I]t is important that we avoid im-
 porting limitations from the specification into the claims.”)
 (internal quotation marks omitted).
     Moreover, the district court’s construction is supported
 by the extrinsic evidence. In construing surfactant, the
 court relied on Dr. Forrest’s testimony that a peptide for-
 mulator in 2002 was aware that surfactants usually, but
 not necessarily, reduce interfacial tension. The court found
 his testimony “more thorough and reli[ant] upon a more
 authoritative list of sources” than Maia’s expert, Dr.
 Klibanov, who asserted that surfactants must reduce inter-
 facial tension at certain interfaces. Claim Construction Or-
 der, 2019 WL 4885888, at *8. We do not see, nor does Maia
 allege, any clear error in the court’s reliance on Dr. For-
 rest’s testimony over Dr. Klibanov’s testimony.
                        CONCLUSION
     We have considered the parties’ remaining arguments
 but find them unpersuasive. For the foregoing reasons, we
 conclude that while the district court technically erred in
 construing the terms buffer, surfactant/solubilizer, and
 surfactant, its construction is essentially correct. We
 therefore affirm the judgment of infringement.
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                       AFFIRMED