Partially Neutralized Acid Does not Infringe Acid Claim?
In Kao Corporation, et al. v. Unilever United States, Inc., et al. (Fed. Cir. March 23, 2006), the court interpreted the claimed "PVM/MA" copolymer for removing blackheads excluded the PVM/MA acid-salt used by Unilever's product, which contained 98% by weight of PVM/MA copolymer and 2% by weight of aminomethyl propanol ("AMP"). Kao argued that 1) Unilever's product in fact uses the PVM/MA acid, and not the salt ; and 2) even if Unilever's product does use the salt, this court's precedent provides that a salt can infringe an acid claim "if the salt provides the same beneficial effect as the acid."
According to the opinion by Circuit Judge Gajarsa:
Kao argues that, contrary to the district court's finding, "Unilever does
not use the salt" form of PVM/MA, but the acid form. It bases this conclusion on
the fact that the addition of 2% AMP to the PVM/MA only slightly neutralizes the
acid, such that "85.5% of the acid groups do not include a salt and only 14.5%
of the acid groups include a salt." It repeats its assertion—unsupported by any
reference to the record or any other authority—that the resulting compound is
only "a slightly neutralized acid and not a salt."
Unilever retorts that "[a]ll of the experts agree that a chemical reaction between PVM/MA and AMP results in the formation of a salt." The record
supports this assertion. Kao offers no response to Unilever's account of the
record testimony beyond a conclusory assertion, unsupported by citation to the
record, that Unilever's account is "not correct." We note also that the relevant
claim limitation reads "copolymer" to mean either form of PVM/MA "but not the
salt form thereof." Kao Corp., 334 F. Supp. 2d at 545. The relevant question is
not whether Unilever's compound is a salt, but whether it is "a salt form of"
PVM/MA. Kao has offered this court no basis on which to conclude that it is
not.[Footnote:] In addition, we note that subsequent to filing the '382 Patent, Kao filed a separate application "with claims specifically directed to salts of the copolymers claimed in the '382 patent." Kao Corp., 334 F.Supp. 2d at 546. If Kao had intended to claim salt forms of the copolymer in the '382 Patent, the subsequent patent application would have been superfluous.
Kao also argues that, even if the Unilever product uses the salt, it
nevertheless literally infringes the '382 Patent because "the slight
neutralization" effected by the addition of AMP to PVM/MA "has no affect on the
ability of the claimed PVM/MA to remove keratotic plugs." Kao cites this court's
decision in Merck & Co. v. Teva Pharmaceuticals USA, Inc., 347 F.3d 1367
(Fed. Cir. 2003), for the proposition that "a claim that recite[s] an acid" may
be "literally infringed by the salt of the acid" where "both the acid and its
salt functioned similarly." Here, Kao argues, even Unilever does not dispute
that the chemical changes effected by combining PVM/MA with AMP have no effect
at all on the function of the invention, that is, on the ability to remove
Kao's reliance on Merck and a similar case, Stephens v. Tech International, 393 F.3d 1269 (Fed. Cir. 2004), is misplaced. The portions of those cases addressing the acid/salt issue both involve patent claims that were held to include salt forms. Merck, 347 F.3d at 1371-72; Stephens, 393 F.3d at 1274-75. The district court's claim construction in this case expressly excluded the salt form of PVM/MA, rendering Merck and Stephens readily distinguishable on this, among other, grounds.
Kao also relies on our decision in SunTiger, Inc. v. Scientific Research
Funding Group, 189 F.3d 1327 (Fed. Cir. 1999). SunTiger involved a lens patent
and an alleged infringing product that featured, in addition to a lens similar
to the claimed lens, a gray coating over most of the lens that allegedly altered
the light transmission properties of the lens. The district court granted
summary judgment of noninfringement, concluding that the addition of the coating
"changed an inherent property" of the lens and thereby avoided infringement
despite the fact that a portion of the accused product did, in fact, meet all
the patent's claim limitations. Id. at 1336. We reversed, stating that "we have
never required that a claim read on the entirety of an accused device in order
to infringe," and that one cannot "avoid infringement merely by adding elements
if each element recited in the claims is found in the accused device." Id.
Kao analogizes to our ruling in SunTiger, arguing that here, as in that
case, the addition of a novel element—here, the AMP—does "not fully eliminate an
inherent feature of the claim"—here, "the ability of the PVM/MA to remove
keratotic plugs." Kao's analogy is unhelpful. The core principle of SunTiger is
that the failure of some portion of an accused product to meet all the claim
limitations is insufficient to sustain summary judgment of noninfringement where
another portion of the accused product does meet all the claim limitations. That
is not the situation here, where—because the district court did not err in
determining that Unilever's product used a salt, not the claimed acid—no portion
of the accused product meets all the claim limitations. Where, as here, no part
of the accused infringing product meets all the claim limitations of the patent,
the remedy available to the patentholder is an action under the doctrine of equivalents. Kao has not raised a doctrine of equivalents argument, and its literal infringement argument fails.
Circuit Judge Newman, a Chemistry PhD from Yale University, dissented on this point noting that
My colleagues appear to have been taken in by the carefully phrased UnileverBradley W. Crawford at the Patently-O Blog summed up the decision with this note to all of the chemical patent drafters: "If you are claiming compounds that contain acids or bases, you have to disclose and claim the corresponding salts. You just have to."
statement that "'[a]ll of the experts agree that a chemical reaction between
PVM/MA and AMP results in the formation of a salt.'" Maj. op. at 16. Of course a
reaction between an acid and a base produces a salt. But a reaction between
14.5% of the acid and matching amount of base produces 14.5% salt, leaving 85.5%
unreacted acid. From my colleagues' inaccurate science, and the conclusion drawn
therefrom, I must, respectfully, dissent.