Opinion ID: 4560751
Heading Depth: 2
Heading Rank: 1

Heading: “Antibody”

Text: Claim 1 of the ’590 patent recites “[a]n isolated antibody or antibody fragment thereof that binds Factor IX or Factor IXa and increases the procoagulant activity of Factor IXa.” Therefore, contrary to the district court’s construction, nothing in the plain language of claim 1 limits the term “antibody” to a specific antibody consisting of two identical heavy chains and two identical light chains or an antibody that only binds the antigen that induced its synthesis or very similar antigens. The dependent claims confirm that “antibody” is not so limited. For example, dependent claim 4, recites “[t]he antibody or antibody fragment according to claim 1, wherein said antibody or antibody fragment is selected from the group consisting of . . . a chimeric antibody, a humanized antibody, . . . [and] a bispecific antibody.” Each of these claimed “antibodies” falls outside of the district court’s construction because each does not “only bind[] to the antigen that induced its synthesis or very similar antigens.” 3 A 3 The ’590 patent explains that a humanized anti- body has a structure of a human antibody but combines non-human antibody portions, such as the complement determining regions (CDRs), with human antibody portions. ’590 patent at 6:50–7:1. It explains that a chimeric antibody differs from a humanized antibody in that it comprises the entire variable regions of non-human origin in combination with human constant regions. Id. Finally, it explains that a bispecific antibody has “two different binding specificities within one single molecule,” i.e., it can bind two different antigens. Id. at 7:32–38. It is undisputed Case: 19-1527 Document: 59 Page: 8 Filed: 08/27/2020 8 BAXALTA INC. v. GENENTECH, INC. “bispecific antibody” also does not satisfy the district court’s construction of “antibody” because a bispecific antibody does not consist of two identical H chains and two identical L chains. Dependent claim 19 further limits claims 1 and 4 by claiming that the “antibody is a humanized antibody,” which again does not fall within the district court’s construction of “antibody.” The district court’s construction which excludes these explicitly claimed embodiments is inconsistent with the plain language of the claims. 4 See Intellectual Ventures I LLC v. T-Mobile USA, Inc., 902 F.3d 1372, 1378 (Fed. Cir. 2018); see also Ortho-McNeil Pharm., Inc. v. Mylan Labs., Inc., 520 F.3d 1358, 1362 (Fed. Cir. 2008) (rejecting a construction that would “render several dependent claims meaningless”). that humanized antibodies, chimeric antibodies, and bispecific antibodies fall outside the district court’s construction. See Genentech Resp. Br. at 1, 53; Baxalta Op. Br. at 12. 4 Baxalta argues that the district court’s claim construction is also inconsistent with dependent claims 7, 9, 11, 18, 21, and 22 because they require synthetic production methods that do not “only bind[] to the antigen that induced its synthesis or very similar antigens.” Baxalta Op. Br. at 31–32. Baxalta also argues that the district court’s construction excludes claimed embodiments in claims 3 and 20, which recite that the antibody is an “IgG, IgM, IgA or IgE antibody.” Genentech agrees that IgM and IgA antibodies do not necessarily meet the district court’s construction requiring that the antibody consist of two identical H chains and two identical L chains. Genentech Resp. Br. at 9, 36. We note that when a construction such as this is inconsistent with the plain language of the claims and the written description, it is incorrect. Case: 19-1527 Document: 59 Page: 9 Filed: 08/27/2020 BAXALTA INC. v. GENENTECH, INC. 9 The district court rejected this inconsistency, suggesting that the proper result here is “invalidation of the inconsistent claims rather than an expansion of the independent claims.” Baxalta, 2018 WL 6304351, at . Similarly, Genentech invites us to assume that the examiner simply overlooked at least these dependent claim limitations when he allowed the claims. See Genentech Resp. Br. at 53 and Baxalta Inc. v. Genentech, Inc., No. 19-1527, Oral Arg. at 34:44–35:12, available at http://oralargu- ments.cafc.uscourts.gov/default.aspx?fl=2019-1527.mp3 (counsel for Genentech explaining “we don’t have an answer to why [bispecific antibodies are] there except that they stood rejected and somehow got allowed”). Genentech argues that because the patent defines the term “antibody” in column 5, we should invalidate all dependent claims which would not be consistent with that definition such as claims 4 and 19. We do not agree. The plain language of these dependent claims weighs heavily in favor of adopting Baxalta’s broader claim construction. And as in Intellectual Ventures I, we reject the district court’s construction which renders dependent claims invalid. 902 F.3d at 1378.
Under the heading “Antibodies and Antibody Derivatives,” the patentee explains: Antibodies are immunoglobulin molecules having a specific amino acid sequence which only bind to antigens that induce their synthesis (or its immunogen, respectively) or to antigens (or immunogens) which are very similar to the former. Each immu- noglobulin molecule consists of two types of polypeptide chains. Each molecule consists of large, identical heavy chains (H chains) and two light, also identical chains (L chains). ’590 patent at 5:56–65. The district court determined that this portion of the written description defined the term “antibody.” While this is a plausible reading of the excerpt in Case: 19-1527 Document: 59 Page: 10 Filed: 08/27/2020 10 BAXALTA INC. v. GENENTECH, INC. isolation, claim construction requires that we “consider the specification as a whole, and [] read all portions of the written description, if possible, in a manner that renders the patent internally consistent.” Budde v. Harley-Davidson, Inc., 250 F.3d 1369, 1379–80 (Fed. Cir. 2001). When considered in the context of the remainder of the written description and the claims, we read the excerpt in column 5 as a generalized introduction to antibodies rather than as a definitional statement. We also note that these general statements do not include terms we have held to be limiting in other contexts such as “the present invention includes . . .” or “the present invention is . . .” or “all embodiments of the present invention are . . . .” Luminara Worldwide, LLC v. Liown Elecs. Co., 814 F.3d 1343, 1353 (Fed. Cir. 2016). Beyond this general description in column 5, the written description provides specific disclosures regarding bispecific, chimeric, and humanized antibodies and methods of production thereof, all of which do not comport with the district court’s construction. For example, the written description explains that “[t]he inventive antibodies and antibody derivatives and organic compounds derived there from comprise . . . bispecific antibodies.” ’590 patent at 6:1–6. Both parties agree “bispecific antibodies” do not consist of two identical H chains and two identical L chains and thus fall outside the district court’s construction. See, e.g., Baxalta Op. Br. at 30 n.16; Genentech Resp. Br at 1. The written description further discloses that “antibodies and antibody derivatives may also include . . . ‘technically modified antibodies’ such as . . . chimeric or humanized antibodies . . . . In these technically modified antibodies, e.g., a part or parts of the light and/or heavy chain may be substituted.” ’590 patent at 6:15–24. And the written description explains that “[t]he antibodies of the present invention can be prepared by methods known from the prior art, e.g. by conventional hybridoma techniques, or by means of phage display gene libraries, immunoglobulin chain shuffling or humanizing techniques.” Id. at 7:65–8:3 (emphasis Case: 19-1527 Document: 59 Page: 11 Filed: 08/27/2020 BAXALTA INC. v. GENENTECH, INC. 11 added). The written description, therefore, discloses synthetic techniques for preparing antibodies such as humanized or chimeric antibodies, which are inconsistent with the district court’s claim construction requirement that the antibody “only binds to the antigen that induced its synthesis or very similar antigens.” Recognizing that these disclosed techniques for preparing the claimed antibodies would result in antibodies excluded by the district court’s construction, Genentech’s response was “I hesitate to say that that’s a typo.” Baxalta, No. 19-1527 Oral Arg. at 37:02–38:26. Genentech does not dispute that the written description discloses antibodies that fall outside the district court’s construction, but rather argues that “there is no legal problem with a claim construction that excludes certain disclosed embodiments, where the specification otherwise supports that construction.” Genentech Resp. Br. at 1, 60–61. To adopt Genentech’s construction, we would need to invalidate several dependent claims, which according to Genentech, the examiner overlooked in allowing, and to conclude that preparation techniques for the claimed antibodies included in the written description were disclosed in error. See Baxalta, No. 19-1527 Oral Arg. at 31:37–32:26 (counsel for Genentech conceding that “[claim 19] and claim 4 are inconsistent with the notion that column 5 is a definition of ‘antibody’”). As discussed, column 5 is not definitional, and the remainder of the written description and claims do not support the district court’s construction. The claim construction excluding these disclosed and claimed embodiments is therefore incorrect.
The prosecution history does not, as the district court suggests, “confirm[] the specification’s definition of antibody.” Baxalta, 2018 WL 6304351, at . We have recognized that the prosecution history “often lacks the clarity of the specification and thus is less useful for claim construction purposes.” Phillips v. AWH Corp., 415 F.3d 1303, Case: 19-1527 Document: 59 Page: 12 Filed: 08/27/2020 12 BAXALTA INC. v. GENENTECH, INC. 1317 (Fed. Cir. 2005) (en banc). While a patentee cannot recapture specific constructions disclaimed during patent prosecution either through amendment or argument, we do not apply the doctrine of prosecution history disclaimer where the alleged disavowal is less than clear. Avid Tech., Inc. v. Harmonic, Inc., 812 F.3d 1040, 1045 (Fed. Cir. 2016). The district court’s analysis centered around the patentee’s amendment substituting the term “antibody fragment” for “antibody derivative,” at the examiner’s suggestion, to overcome an enablement rejection. See J.A. 15987, 16008, 16012, 16017–21. Based on its previous definition of “antibody derivatives” as “antibodies within the column 5 definition that had been altered in some significant way,” e.g., bispecific antibodies, Baxalta, 2018 WL 6304351, at –7, the district court determined that the amendment from “antibody derivative” to “antibody fragment” amounted to a disclaimer of antibody derivatives “including bispecific antibodies, except antibody fragments.” Id. at –8 (emphasis in original). Because we reject the premise that the excerpt of column 5 is definitional, and do not view the prosecution history as sufficiently clear and unmistakable, we conclude that the prosecution history is insufficient to overcome the meaning of “antibody” we discern from the claims and the written description. First, there are no clear statements in the prosecution history regarding what scope, if any, was given up when the patentee substituted “antibody fragment” for “antibody derivative.” “[I]n order for prosecution disclaimer to attach, the disavowal must be both clear and unmistakable.” 3M Innovative Properties Co. v. Tredegar Corp., 725 F.3d 1315, 1325 (Fed. Cir. 2013). Both parties agree that the term “antibody derivative” is not a term that is commonly used in the art. Baxalta, 2018 WL 6304351, at . It is plausible, therefore, given the ambiguity regarding this amendment, that the patentee was substituting a known term at the suggestion of the examiner for a less commonly used term in the art. In fact, the written description Case: 19-1527 Document: 59 Page: 13 Filed: 08/27/2020 BAXALTA INC. v. GENENTECH, INC. 13 appears to use them almost interchangeably. See, e.g., ’590 patent at 6:20–22 (identifying Fv, Fab, Fab', and F(ab)’2 as examples of antibody fragments); id. at 20:35–36 (identifying scFv and Fab as examples of antibody derivatives); id. at 30:15–17 (identifying Fab, F(ab)2, and scFv as examples of antibody derivatives). The prosecution history, therefore, does not clearly establish disclaimer. Second, the district court’s determination that the patentee disclaimed antibody derivatives “including bispecific antibodies, except antibody fragments” is inconsistent with the examiner’s subsequent allowance of at least claim 4. As explained above, claim 4 explicitly claims “a bispecific antibody,” a claimed embodiment directly at odds with a disclaimer theory. The prosecution history, therefore, does not support the district court’s construction of “antibody.” The parties agree that Baxalta’s and Genentech’s proposed constructions are recognized meanings of “antibody.” We hold that the district court erred in selecting the narrower construction, which is inconsistent with the written description and the plain language of the claim. Consistent with the claims and the written description, we instead construe “antibody” as “an immunoglobulin molecule having a specific amino acid sequence comprising two heavy chains (H chains) and two light chains (L chains).”