Case No. 2012-1420 (Rader, Clevenger, Prost)
Negative claiming has its uses, but not as a dodge of the written description requirement or a way to sneak in new matter. In re Bimeda is a short opinion that particularly shows how disclosure of a negative genus does not always support later claims to a negative species, just as is the case with the positive claiming. The familiar lessons to disclose fine details, actual species, and guidance for identifying the same within genera apply mutatis mutandis when negative claiming.
Bimeda owned US Patent 6,506,400 directed to prevention of mastitis, an infection of udders in milking animals. The claimed method used a special teat seal to block infectious agents from a teat canal. When the ‘400 patent was subject to ex parte reexam over prior art using anti-infective agents including an antiseptic called acriflavine in similar seals, the patentee added new claims that precisely cut around the prior art having these agents with the following negative limitations:
18. A prophylactic method of controlling infection in a mammary gland by a mastitis-causing organism, comprising sealing a teat canal of a mammary gland with a seal formulation so as to provide a physical barrier in the teat canal, wherein the seal formulation is free of an agent that is anti-infective . . .
32. A prophylactic method of controlling infection in a mammary gland by a mastitis-causing organism, comprising sealing a teat canal of a mammary gland with an acriflavine-free seal formulation so as to provide a physical barrier in the teat canal. . .
The ‘400 patent specification explicitly disclosed “antiinfective-free” seal formulations, in direct contrast to prior art that used antibiotics to control mastitis-causing organisms. As such, claim 18 was allowed without problem. According to the patentee, because the specification disclosed embodiments lacking anti-infectives, the specification necessarily disclosed acriflavine-free embodiments as recited in claim 32, because acriflavine was an anti-infective well-known in the art to treat mastitis. The Board did not agree and affirmed rejections to claim 32 as lacking written description because the specification never mentioned the specifically-(dis)claimed acriflavine.
The Federal Circuit affirmed the Board. The opinion went through each embodiment of the ‘400 patent specification, noting that absence of all antibiotics in the seal formulations was a key feature highlighted in each one. New claim 32, however, contemplated the use of other antibiotics in the formulation, as long as acriflavine was omitted. It was this difference between the specification and claim – always-antibiotic-free versus permitting-some-antibiotics-but-not-acriflavine – that showed a lack of written description here:
the disclosure is generally inconsistent with a formulation which, like claim 32, excludes acriflavine but could include antibiotics. As noted above, the summary of the invention describes the invention’s “non-antibiotic approach” to preventing mastitis, and explains how this approach achieves the benefit of “meeting consumer preferences for reducing the levels of antibiotics used in food production.” ’400 patent at col.1 ll.35-42.
The remainder of the disclosure similarly distinguishes the invention due to its ability to prevent mastitis without using antibiotics. . . .[T]he patent discloses that the invention presents “no risk of antibiotic residues after calving,” id. at col.5, ll.16–17, which seemingly can only be true if the formulation excludes all antibiotics. The specification thus leaves no room for argument that the inventor possessed a formulation that excludes only acriflavine while permitting the use of antibiotics.
Judge Rader wrote a brief concurrence to highlight the problems with framing written description in terms of “possession,” when negative claiming is all about not having possession. For the concurrence, the usual positive-claiming written description test, looking for disclosed “blaze-marks” to claimed species, was somewhat inapt here. Acriflavine was a well-known type of anti-infective that was clearly identifiable within the field of mastitis treatment, so its inclusion may have had written description. Thus, it was the specification’s insistence on absolutely no type of antibiotic that precluded negative claiming of anti-infective species that would permit the presence of other antibiotics:
“The name of the game is the claim.” In re Hiniker Co., 150 F.3d 1362, 1369 (Fed. Cir. 1998) (quoting Giles Sutherland Rich, Extent of Protection and Interpretation of Claims-American Perspectives, 21 Int’l Rev. Indus. Prop. & Copyright L. 497, 499 (1990)). Here, the Board refused to wrestle with the fact that the claim at issue (and the patent as a whole) focuses on negative claiming. That is, the claim at issue specifically excludes an element, acriflavine, from the claimed formulation. J.A. 9. Yet the Board discusses written description in the context of claiming the inclusion, not the exclusion, of a particular element.
. . .The adequacy of written description must be determined on the facts of each case. In re Jolley, 308 F.3d 1317, 1323 (Fed. Cir. 2002). Here, the specification clearly supports a formulation which excludes all antiinfectives.
Written description rejection to claim 32 affirmed.
Lessons: I’ve previously discussed some benefits and problems with negative claiming, including its effectiveness vel non in exactly overcoming prior art and differing treatment in foreign jurisdictions, but the lesson to focus on from Bimeda is more of when you can actually negatively claim undisclosed species or details. From the case, it looks like negative claiming is very much subject to the same rules as positive claiming, and use of a negative claim limitation will not avoid the need to disclose details and specific alternatives within a broad genus in order to negatively recite applicable species therein. If anything, Bimeda simply reiterates the Gentry Gallery rule, but in terms of negative limitations: Don’t disclose species as overwhelmingly mandatory features of “the invention” in the specification and then try to add a claim to a genus including different species. For negative claiming, this means don’t disclose exclusion of a genus as a mandatory feature of the invention in the specification and then try to add a claim excluding only some species of the genus. Had the patentee in Bimeda instead disclosed individual species of antibiotics that could be excluded in any combination, or permissibly identified types of consumer-acceptable anti-infectives that were useable in example embodiments, they would probably have had a much easier time negative claiming different types of well-known anti-infectives like acriflavine, regardless if they were disclosed by name in the specification.
Comment: This seems correct to me. I find Judge Rader’s concurrence similar to his approach to written description in the recent Novozymes case. For him, there seems to be an emphasis that written description should very much look outside as well as inside the specification. “Blaze marks” within a genus being put forth in the specification are just as important as the skilled artisan’s knowledge and ability to identify claimed species outside the specification. I find this approach closer (although not identical) to an enablement inquiry, at least as to what evidence is applicable to show both written description and enablement.
On a personal note, I think every patent prosecutor at some point in their career handles applications in a narrow technological area unfamiliar to them and really almost anyone else. For me, that field was cow milking, so Bimeda’s discussion of mastitis prevention and treatment brings back some milky-watered colored memories for me.