A Higher Written Description Standard for Negative Claim Limitations?

By Dennis Crouch

Santarus and the University of Missouri v. Par Pharma (Fed. Cir. 2012)

My employer (University of Missouri) owns several patents covering formulations of omeprazole proton pump inhibitors (PPIs). The patents are exclusively licensed to Santarus who markets the drugs under the brand Zegerid®. Par filed its request to make a generic version which prompted this infringement litigation.

The inventor, Dr. Jeff Phillips is a pharmacist at MU had the simple idea of combining omeprazole with baking soda (sodium bicarbonate). The baking soda helps the drug resist stomach acids long enough to be absorbed in the stomach wall. Although not a blockbuster drug, the approach has been successful for many patients with GERD and Santarus sales are about $40 million per year. (The reported deal is that MU receives about 5% of sales. As the inventor, Phillips receives a small cut from that.)

During litigation the patents were successfully attacked as obvious based upon a preliminary written description challenge.

Written Description Killing Priority and thus Nonobviousness: We know that patent applicants are allowed to narrow patent claims during the prosecution process. The vast majority of issued patent claims are not found in the originally filed patent application but instead are amended during prosecution. This is typically done by adding limitations into the claims as MU did here. The primary constraint on adding limitations is that the newly amended claim must be supported by the original application specification. Thus, a patentee cannot create limitations from thin-air, but must instead identify limitations found in the specification to be added into the claims. In the simple case, newly added claim limitations that are not supported by the specification are rejected for new matter at the USPTO and, once issued, can be invalidated for lacking written description under 35 U.S.C. § 112. The situation is a bit more confusing when the application claims priority to a prior patent filing. Of course, most issued patents do claim priority to a prior patent filing so the family member situation is quite important. In the patent family context, a child application might fully comply with the written description requirement if considered on its own. The child application can also be valid if new matter was added to the specification or claims at the time of filing. However, that new matter (if included within the claims) will mean that the patentee cannot claim priority to the parent application’s filing date. Where the parent case is published more than one year before the patent filing, that parent application can also serve as a prior art against the child application under 35 U.S.C. §102(b) unless priority can be established. (Query how this will works under the AIA?)

In this case, the generic challenger argued that one of the claimed limitations was not supported by the parent patent and, as a consequence, that parent patent serves as a critical piece of prior art that invalidates the claims.

One set of asserted claims were amended from the priority filing to included an exclusionary wherein limitation. In particular, the claims stated that “the composition contains no sucralfate.” The original specification had noted several reasons why omeprazole was preferable to sucralfate. In the same sentence, the specification also indicated that omeprazole is also preferable to sodium bicarbonate for those same reasons. Since sodium bicarbonate is actually an element of the invention, the district court held that the same sentence could not be used to particularly exclude sucralfate without further evidence that sucralfate is contraindicated. On appeal, the Federal Circuit rejected this reasoning – holding that preference statement in the specification was sufficient to justify addition of the exclusionary limitation and that the sodium bicarbonate inclusion (as a buffer) was justified by other portions of the specification.

Higher Bar for Negative Limitations?: The exclusionary limitation here is a negative limitation because it defines what the invention does not contain. Here, the invention does not contain sucralfate. The tradition in patent law has been to avoid negative limitations and, certainly, an invention cannot be wholly defined by negative limitations. However, negative limitations are allowed and are useful at times. It appears that the court sets a higher bar for the inclusion of negative limitations than it does positive elements of a claim. This is done by requiring that the specification include a reason for the exclusion in order to satisfy the written description requirement. The court writes here: “Negative claim limitations are adequately supported when the specification describes a reason to exclude the relevant limitation.” Ordinarily, such justification is not required for positive claim elements – although justifying explanations can be helpful in justifying greater claim breadth.

Although some reasoning is required, the patentee need not disclaim the element in the specification in order to add the exclusionary limitation in the claims. “Such written description support need not rise to the level of disclaimer. In fact, it is possible for the patentee to support both the inclusion and exclusion of the same material.”

With these notions in mind, the court held that the statements in the specification were sufficient to support the exclusionary limitation in this case. “The claim limitation that the Phillips formulations contain no sucralfate is adequately supported by statements in the specification expressly listing the disadvantages of using sucralfate.” And, as a consequence, the parent patent is not a proper prior art reference against those claims supported by the original specification.

Patent with Multiple Priority: In cases with a complex family structure, patent priority is actually determined on a claim-by-claim basis. As discussed above, the Federal Circuit held that some of MU’s claims properly claim priority to the original specification filed with the USPTO. On appeal, the patentee implicitly agreed that some of the other patent claims are not supported by the original specification. For those cases, the original filing qualifies as prior art against the no-priority claims under section 102(b). The question then is whether the newly added material is sufficiently different to avoid invalidation on obviousness.

Without going into detail, the Federal Circuit found that some of the patent claims that qualified for priority were also nonobvious and thus should be treated as valid and enforceable.

Need one to win: In the end, this appears to be a win for Mizzou since a patentee only need a court to find one of its claims is infringed and enforceable.

Notes:

  • Although I am employed by the University of Missouri, the university is not my client and I have not spoken with any of the university counsel about this case.
  • Par also appealed the district court’s finding of no inequitable conduct. The Federal Circuit affirmed that holding based upon a lack of clear and convincing evidence of intent deceive the USPTO.

48 thoughts on “A Higher Written Description Standard for Negative Claim Limitations?

  1. 48

    MM–

    Thanks for that response.

    I understood that to be the case when I made the comment, which was why I included the proviso “if it was supported in the spec”.

    What would your opinion be of your hypothetical negative limitation in that situation?

  2. 47

    Ned–

    Thanks for that.

    In your first paragraph you consider the genus-anticipating-species situation, which was not the issue in this case.

    In your second paragraph, your first sentence is, with respect, merely conclusory. I asked WHY you believe it would be in fact anticipated. Without more information, only 5 would be clearly anticipated.

    We now arrive at the situation where the maxim “that which infringes if later, anticipates if earlier”. If the PA is so limited as to be confined to 5, there is no literal infringement by a claim that reads “1-10 not 5”, leaving one with infringement under the DOE.

    The question then becomes to what range of equivalents the prior art is entitled, which in many situations brings up the function-way-result of Graver Tank. The concept of “criticality” or “patentable distinction” is shorthand for an applicant’s argument that the claim discloses a patentably different function-way-result than does the prior art.

    This brings us again to the critical language in this opinion: “In fact, it is possible for the patentee to support both the inclusion and exclusion of the same material.” Presumably, exclusion is tantamount to patentable distinction.

    It comes down to what is disclosed in the application. Like MM said below, a type of generic disclosure will not be sufficient to demonstrate possession of the invention–but the open question is, can a disclosure be sufficiently specific to demonstrate possession of the invention while simultaneously supporting both the inclusion and exclusion of the same material?

  3. 46

    In re Ruesectta is interesting for two reasons. First, its reliance on Muncie Gear, and second for its facts.

    The prior art Talyor patent disclosed a condenser having electrodes of zirconium, titanium and columbium (another name for niobium). The priority application disclosed and claimed etching a hard metal, titanium, to reduce its surface area for use in the Talyor condensor. The CIP extended this to the other metals Taylor listed.

    The court (Rich) held that this would be obvious to extend the same process of the priority application to the known hard electrode materials listed in Taylor.

    So? Why then wasn’t the original disclosure generically enabling, then? Why weren’t the claims supported?

    Given the original disclosure supported the broader claim, wasn’t the real problem of Ruescetta one of double patenting?

    For example, had another inventor filed an application claiming the etching process using all of metals of the prior art, the PTO would have required an interference. The PTO could have given priority not only of the one species to the first to invent the etching process, but also to the genus. This doubly supports the notion that the claims were supported.

    Turning to Muncie Gear, new subject matter added by amendment was added more than two years after that very same new subject matter was in the public domain via public use. Clearly, Muncie Gear does not stand for the proposition that Rich cited it for, that the old subject matter was a bar when the CIP claimed the benefit of the early filing date.

    There are a lot of problems with In re Ruescetta.

  4. 45

    Inviting, if a range or genus is in the prior art, one can still obtain a patent on a species or subrange if the applicant discloses criticality. Conversely, if there is no criticality, to grant such a patent on a species without criticality would be to withdraw subject matter from the public.

    If during original prosecution, I disclose 1-10 and the prior art is 5, the broad claim is anticipated. The question then becomes do I have have disclosure for some subrange that is critical. I simply cannot patent the whole range 1-10, not 5 without showing some criticality for two new subranges.

  5. 44

    MM, why would the negative limitation be impermissible if it was supported in the spec?

    In my hypo, there is no literal support for the limitation, only a general recognition that the prior art is (1) different from the “invention” and (2) inferior to the “invention.” Such a generic disclosure seems to be to be per se insufficient to show possession of the “invention” that is “discovered” only after a specific piece of prior art is presented to the applicant by the USPTO.

  6. 43

    In some cases, I think this actually rises to the level of post-filing invention, because it is clear that the inventors had no idea that the application could cover what the claims try to cover.

    The reverse doctrine of equivalents isn’t dead — it just smells funny.

  7. 42

    Look at the cases going backward, using the 2 cases in MPEP 2131.02 as a starting point:

    Gosteli says nothing other than that the parties agreed that the prior case Slayter stood for the proposition that a species anticipates a genus.

    link to law.justia.com

    Slayter was essentially an “inherent anticipation” case, not a species-anticipating-genus case. In this opinion, 3 representative claims were considered—claims 1, 4, and 34. Claim 1 was disposed with on the basis of “inherent anticipation”, the court having found that the claimed patentable distinctions were nothing but “the normal practice” of the prior art. Also, some of the patentable distinctions in claim 1 were disposed of on the basis of obviousness, as “clearly suggested” by and “obvious in view of” the prior art. The additional limitations that claims 4 and 34 attempted to add to claim 1 were disposed of as “somewhat indefinite”, and in any event “functional” in nature, describing not structure but the method of making the structure. When the applicant tried a functional limitation argument, the court ruled on the basis of “inherent anticipation” that the limitation was in fact disclosed in the prior art, and that the nature of the function was no different, but that it was “at best, only a matter of degree”. The court thus disposed of the claims on these bases, not on that of “species-anticipating-genus”. In fact, the only time the opinion mentions that concept is cursorily in the last paragraph, without any analysis whatsoever as to whether or not the prior art did disclose a species of whatever genus might have been disclosed in the claims at issue—it states that it simply “assumes the truth” of the appellant’s argument that a genus is disclosed in the claims, and then makes the equally facile assumption that the prior art disclosed a species falling squarely within that genus. The opinion claims that the species-anticipating-genus concept is “well settled”, and cites 3 earlier decisions in support, 2 Sup. Ct. decisions, and 1 2nd Circuit decision—Peters, Knapp, and Faries Mfg, respectively.

    link to bulk.resource.org

    Peters was essentially an “inherent anticipation” case, not a species-anticipating-genus case, with the court having relied on its findings that the claimed patentable distinctions were nothing more than “inevitable consequences” of the prior art, that the results were nothing more than “the well known action” of the prior art, that the patentable distinction “necessarily” occurred, and hence did not distinguish over the prior art. A brief obviousness pronouncement also played a part in the court’s rejection of a limitation as a patentable distinction, but neither “inherent anticipation” nor “obviousness” says anything about “species-anticipating-genus”.

    link to supreme.justia.com

    Knapp had absolutely nothing to do with species-anticipating-genus. It was an invalidity decision based primarily upon obviousness, and secondarily upon anticipation. Continued reference is made to mere “adapt[ation of] the application of old devices to a new use” requiring “hardly more than mechanical skill”, and to “function, way, result” language made famous in Graver Tank when referring to equivalents. In fact, quite apart from the finding of a species in the prior art having more limitations than any genus that might be present in the claims, the court went on to consider the exact opposite scenario, in which it was instead the claimed invention, rather than the disclosure in the prior art, which was characterized as the species. 2 justices dissented from the conclusion of obviousness, but would have nevertheless held the claims invalid on the basis of the DOE. I cannot see any rational basis for the court in Slayter having referenced this opinion as informative of the species-anticipating-genus issue.

    link to supreme.justia.com

    Faries Mfg also had nothing to do with species-anticipating-genus. Prior art was found that predated the claims, and that served as precise precedent for the allegedly infringing device. Species-anticipating-genus was not even considered: ” Whether or not it anticipates appellee’s [patentee’s] device or lamp, we need not say.” In fact, this was essentially a genus-does-not-anticipate-species decision:” Appellee [Patentee] must establish that the [allegedly infringing] lamps are sold without the screws [potentially patentably distinct limitations] or that they may be used without the screws[potentially patentably distinct limitations] in ordinary commercial use. It has not succeeded in this claim.” I cannot see any rational basis for the court in Slayter having referenced this opinion as informative of the species-anticipating-genus issue.

    link to vt.findacase.com

    I could go on, drilling down, but it always ends the same way. So again, can you provide some good reason WHY you believe that excluding s-m within the literal boundaries of the claim is improper (Ned), or WHY you believe the negative limitation in the hypo is impermissible (MM), other than just referencing so-called “hornbook law”.

  8. 41

    As I said re the preceeding blog re the dissent in this case:
    First, this issue only occurs where the parent application was published more than a year before the filing date of the CIP, and only as to those claims in the CIP which lack full 112 support in the parent application, so that the CIP is properly denied a priority claim benefit for those claims. [Because those CIP claims are claiming a NEW COMBINATION which is “new matter” not previously disclosed. It is NOT just “new matter” for the newly added claim element.] Thus, the publication of the parent becomes a 102(b) reference, just as to those new combination claims.
    Secondly, that is not new law. It is as old as In re Ruescetta and Jenny, 255 F2d 687, 118 USPQ 101 (CCPA 1958) and Tronzo v. Biomet, Inc., 47 USPQ2d 1829 (Fed. Cir. 1998).

  9. 40

    All good points. So the rhetorical point that filing is the start of the inventive process should be appreciated for its rhetoric.

    I have no idea what this means.

    It sounds like “you’re right, but” – if what you are after is a policy change, a more direct path will smack less of trickery (rhetoric is not the best tool for this job).

    Technically speaking, the full appreciation of the inventor to the invention is only losely required; that is, it must be by the person, and the limits are what is present at filing, but appreciation of everything there is not required. That’s just not our law. In fact, we even allow changing for more up to two years after the public is aware of the patent grant itself.

  10. 39

    In my experience, you often get even more creative “post-filing invention” when it comes time to assert the issued patent…

  11. 38

    All good points. So the rhetorical point that filing is the start of the inventive process should be appreciated for its rhetoric.

    While things cannot be invented after filing, the appreciation that concepts disclosed in the application are inventive can and does arise years after filing.
    You might often encounter claims sets that were clearly born of a late (post filing) appreciation. Sometimes the late “conception” is the result of industry developments (a competitive product) that spur you to mine old applications for supportable claims that the inventor would never recognize as his invention.

    In some cases, I think this actually rises to the level of post-filing invention, because it is clear that the inventors had no idea that the application could cover what the claims try to cover.

  12. 37

    Anon, I agree with you that in every case the majority found that the claims were supported in the parent.  This is why I asked why the priority claim was bad.

  13. 36

    It may not be too much to ask, but in US law, it is not asked (or at least, not asked as directly as you may desire).

    In fact, not including a boilerplate phrase such as ““[] any novel and non-obvious subset of the features disclosed hereinmay be grounds for malpractice. Note that I took the “I claim” portion out, precisely because claims are fluid (and necessarily so). But I also reiterate the distinction that the invention is done and complete as of the filing date. The no new matter rule is every bit as real in the States as elsewhere – anyone who has picked up prosecution of a portfolio that someone (typically) else capable has drafted can attest to that limit (my turn to return the handholding favor to DC and IANAE).

    As to Leopold’s allusion to this being a “dirty little secret,” I think quite the opposite. It is precisly the ability to do this well (and being known for doing it well) that merits the high fees charged for the construction of the patent application.

  14. 35

    This explains why so many US attorneys struggle with EPO added matter practice and why US drafting practice increasingly leads to prosecution problems in Europe … EPO practice expects the applicant to know what it is that s/he thinks s/he has invented and to draft the application on that basis. If that turns out to be old or obvious, then tough, no patent. Sure, you can have fall-back positions in the sub-claims or even just in the description. But there needs to be some indication in the application as originally filed that a particular feature is potentially significant, and to justify its particular combination with other claim features. “Direct and unambiguous” is the standard applied. If you didn’t identify it as clever and significant at the outset, you’ll have a tough time hanging your patent on it later.

    “I claim any novel and non-obvious subset of the features disclosed herein” doesn’t fly…

    If you want 20 years of exclusivity for something, is it too much to ask that you nail your colours to the mast?

  15. 34

    Ned–

    I guess you didn’t see my previous post that I was aware of the species-anticipating-genus situation.

    It all depends on precisely WHAT is claimed, and on HOW it is claimed, does it not? Your simple hypo just disclosed a range, nothing more, so that was the basis upon which I proceeded with my comments.

    Critical in this opinion is the language that “In fact, it is possible for the patentee to support both the inclusion and exclusion of the same material.” So in the strict case of 1-10 describing a genus with substantial commonalities, the species could anticipate the genus…but in the case where the spec could be read either way on various parts of the range, why could the range not be broken up to avoid the prior art?

    Consider it this way as well: what if it were not 5, but 10, that was cut out? This is where your circle analogy breaks down, as the “boundaries” of the claim are still well-defined, especially in the situation where the original disclosure permits either inclusion or exclusion of 10.

    And still waiting for a response from MM. Again, bear with me, I don’t remember my thinking about this matter.

  16. 33

    Ned,

    While Newman speaks broadly of subject matter, I see no support whatsoever for any indication that there is a view to an element by element within a claim case for priority.

    From Newman’s dissent at page 6:

    The panel majority describes this common subject matter at length, but instead of understanding that the common subject matter supports the claims that are entitled to the priority of that subject matter, the panel majority holds that the common subject matter invalidates the claims to that subject matter.” (emphasis added)

    You see intrigue where none exists.

  17. 29

    And yes, I am aware of the species-anticipates-genus situation, because I know somebody will make light of the fact that I haven’t yet explicitly said anything about it.

  18. 28

    Ned–

    Why not?

    What do you believe the difference would be in that form of claim, versus amending to 2 ranges, 1-4 and 6-10? (assuming integers, of course, as you yourself seem to have done for convenience)

  19. 27

    Ned & MM–

    I have thought about the negative limitation issue before, but it is late right now and I can’t remember what my thinking was. I will find it by tomorrow.

    But in the meantime, can you provide some good reason WHY you believe that excluding s-m within the literal boundaries of the claim is improper (Ned), or WHY you believe the negative limitation in the hypo is impermissible (MM).

    Just musing here…I think Dennis might be right by suggesting that your circle analogy has been taken too far, Ned. There is nothing saying that the “literal boundaries” of a claim cannot describe a donut shape, or any other shape for that matter, rather than a circle–that is, consider that your piece of prior art could be in a contained circle, the boundary of which was coincident with the boundary of the larger circle at a point. Your characterization seems artificially limited.

    And MM, why would the negative limitation be impermissible if it was supported in the spec?

  20. 26

    I’m on your side on this one, anon. I think IANAE might have gotten just a little too cute with this comment.

    It might have been somewhat more accurate to say that the drafting/filing marks the point at which the patent attorney starts inventing. Or is that too much of a dirty little secret?

  21. 25

    Granted DC, it is the start of a process. It is hardly the start of the inventive process.

    It’s a distinction pregant with difference, and that difference is birthed in the “no new matter” requirement.

    Whatever “whole new thing” you think the applicant is inventing after filing – cannot be invented after filing because you are stuck with what you filed.

  22. 24

    is nevertheless rendered unpatentable by adding something else, something that is, perhaps, an obvious variation.

    Isn’t it that priority is determined claim by claim in part because claims must be read as a whole?

    And if read, as a whole, the new material must make the claim have a priority that would make the parent claim a qualified prior art reference?

  23. 23

    At filing, you should have a good idea what you think is patentable, but it is impossible to see all and know all. During prosecution, the PTO will reject you based on art you did not see beforehand (you have to file before you can review absolutely every possible piece of prior art). Also, the client will realize that a minor feature is actually critical, which they maybe could not appreciate before filing (you have to file before the client gets much experience with the invention, too). You might often find yourself wishing you had added a few words here and there, or specifically defined a term, or explicitly mentioned that you can do without some element, or you could use a permutation not specifically recited in the spec, etc. So, the filing of the application is the start of the process.

  24. 22

    Wow, good point: why did PAR not add a modicum of the excluded element? A sprinkle would have been enough the defeat literal infringement.

  25. 21

    Paul, on reading the cases you cite, they do not provide a direct rebuttal of Newman’s position. Her position is this

    Parent Discloses A
    CIP discloses A and B, claims A + B.

    The parent is published and a statutory bar to the CIP. This is equivalent to a third party statutory bar reference disclosing A, a reference which has a date after the parent application disclosing A.

    Newman’s position is that the claim to A + B is fully supported and has an effective filing date as to the A subject matter in the parent, a date that effectively antedates against any intervening statutory bar reference disclosing A.

    The two cases you cited are inapposite. The references in each case disclosed subject matter not supported in the the parent – the B subject matter of the hypo. Neither case directly addressed the issue of whether a claim that depends for it novelty on A, that is fully supported in the parent, is nevertheless rendered unpatentable by adding something else, something that is, perhaps, an obvious variation.

    Now, clearly, there should be an obviousness-type double patenting rejection in such a case. But I do not necessarilly see a prior art problem.

  26. 20

    Why wouldn’t an applicant simply claim “consisting of” to avoid the negative limitation problem?

    Because he would introduce a negative infringement problem. A claim to “consisting” would be even narrower than a claim excluding compound C, and could be avoided by adding inert filler without even invoking the apparently horrific contraindications of sucralfate.

    And because maybe he doesn’t have spec support for that either.

  27. 18

    Is it word “comprising” that is causing the problem here?

    Yes, because “comprising” is not limiting.

    Specifically, a prior art composition containing A, B, and C is also a composition comprising A and B. Therefore, it anticipates a claim to “comprising A and B”, but not a claim to “comprising A and B, but excluding C”.

  28. 17

    can you explain “The filing date marks the start of the inventive process, not the end.”

    How’s this for a start:

    “You can’t really know what the claimable invention is until you know what the prior art is, and current IDS law discourages a search.”

    You’ve prosecuted patents before, right? Applicant files original claims distinctly claiming what he regards as the invention. Examiner finds prior art anticipating that invention. Applicant suddenly finds himself regarding a whole new thing as the invention, i.e. amending claim 1. All the while adding no new matter.

  29. 16

    Without going ballistic, can you explain “The filing date marks the start of the inventive process, not the end.” ?

    Please include in your explanation a discussion of “no new matter.”

  30. 15

    Malcolm, help me on the chemistry here.

    The invention is administering omeprazole with a buffer of baking soda, an acid buffer, and not an enteric coating. Omeprazole is a type of PPI. Sucralfate is a type of acid buffering agent old and in common use.

    Why do I have to claim no sucralfate if I claim

    a solid composition “comprising” omeprazole and baking soda? Is it word “comprising” that is causing the problem here?

  31. 14

    Paul, I somewhat agree that Newman’s dissent seems directed to a different majority opinion. Perhaps they redrafted the majority opinion in face of her dissent.

    The bottom line, all claims that were ultimately rejected over the parent ‘773 seem to have been actually supported in the ‘773 such that they should have had the benefit of its filing data had the priority claim been proper. That the priority claim itself it was improper with respect to some of the patents apparently was conceded by the patent owner on appeal. Why it was improper with respect to the conceded patents was not discussed at all in the majority opinion.

    With respect to the patents and claims where the issue was appealed, it appears that the priority claim itself was made. The only issue became whether the claims were supported. I think the Federal Circuit held they were supported in the parent and thus did have the benefit of the parent’s filing date. But I will re-read that portion later to double-check.

  32. 13

    It would have been nice had the court described just why the priority claim was bad in several of the CIPs, but they nevertheless held the claims to be supported in the “parent.”

  33. 11

    Dennis, one example is a range: 1-10. The prior art discloses 5. I cannot claim 1-10, not 5.

    Excuse my chemistry, but the omeprazole is a kind of PPI that needs an entetic coalting. I discover such coating can be omitted if I add baking soda. There might be oher PPIs that need entetic coatings. There might be other buffers than baking soda.

    But without such other examples, can I claim the genus of all uncoated PPIs in combination with all buffering agents?

    Should be a problem under 112, p.1.

    But let us say I do claim that broadly. A piece of prior art is discovered that shows a particular uncoated PPI in combination with a particular buffering agent. Can I maintain the broad claim, and simply exclude the examples?

    No.

  34. 9

    I get the feeling that the need for a negative limitation was identified long after filing, and the patentee got lucky with just enough support for such a limitation.

    The filing date marks the start of the inventive process, not the end. You can’t really know what the claimable invention is until you know what the prior art is, and current IDS law discourages a search. Which leads to problems like the one we have here, namely did the inventor know that this particular difference between the spec and the prior art was interesting?

    Apparently you can get away with a lot, as long as you throw in enough weasel words to support every possible limitation having both good things and bad things about it.

    I would have expected a much higher bar for negative limitations. There should be something more tangible or definite about the negative limitation than the mere absence of A. There’s a difference between “does not contain A” and “contains an A-shaped hole”. I’m on the fence as to whether it’s good enough that the invention was apparently to add B (also claimed) so that you could leave out A and still have an effective medication.

    I suppose it’ll have to be good enough that they’re roadmaps for noninfringement. Speaking of which, any idea why the defendant didn’t sprinkle on a dash of sucralfate? Surely there’s a low enough dosage to be mostly harmless while still being more than “no sucralfate”. Unless they wanted to put a big, bright “contains no sucralfate” label on it.

  35. 8

    Judge Newman’s dissent is troubling in that it contributes to a common misunderstanding of CIP practice. She states that “The panel majority also holds that the disclosure in a parent patent is a reference against the common disclosure in a continuation-in-part patent, again tainting many properly granted patents.” She supports arguments against this only by citations to some patent law treatises. But that is not the issue or the decision in this case.
    First, this issue only occurs where the parent application was published more than a year before the filing date of the CIP, and only as to those claims in the CIP which lack complete 112 support in the parent application, so that the CIP is properly denied a priority claim benefit for those claims, and thus the publication of the parent becomes a 102(b) reference, as the majority says.
    Secondly, that is not new law. It is as old as In re Ruescetta and Jenny, 255 F2d 687, 118 USPQ 101 (CCPA 1958) and Tronzo v. Biomet, Inc., 47 USPQ2d 1829 (Fed. Cir. 1998).

  36. 6

    I can see Ned’s point in the following scenario:

    Background (in its entirety): “Prior art thingamabobs suffered from excessive heating during operation and were not cost-effective to produce. This invention addresses those problems and others.”

    Claim: A thingamabob comprising X and Y.

    Prior art cited: A thingamobob comprising X and Y and Z.

    Amended claim with impermissible negative limitation: A thingamabob comprising X and Y, wherein said thingamabob does not include prior art thingamabobs.

    That sort of scenario.

  37. 5

    I think the Federal Circuit threw you a bone here. I think they have actually stated a low bar for supporting negative limitations. It would have been better to positively recite the negative limitation, as in “you can make it without sucralfate, which may be advantageous because ….” Merely reciting some reason not to include the excluded limitation, as the Court allows here, seems risky, when the patent drafter could, if he realized the import making the drug without sucralfate, could easily have “raised it to the level of a disclaimer.” In another paragraph, he could also have described use of the drug with sucralfate, but this might the application schizophrenic, unless the drafter clearly indicates that he is describing two different inventions with two distinct advantages.
    As a drafting lesson, failure to explicitly state the negative limitation, as in “the new compound is made without any element X” may be required in other countries, so drafters should attempt to identify valuable negative limitations and state them explicitly. If only it were easy to do that!
    I get the feeling that the need for a negative limitation was identified long after filing, and the patentee got lucky with just enough support for such a limitation.

  38. 4

    Ned, I think this may be taking the "invention is a circle" analogy a bit too far.  I don't really understand what a hole in the circle would mean in practical terms. 

  39. 3

    some reasoning is required, the patentee need not disclaim the element in the specification in order to add the exclusionary limitation in the claims. “Such written description support need not rise to the level of disclaimer. In fact, it is possible for the patentee to support both the inclusion and exclusion of the same material.”

    It would seem that if the Applicant wishes to have it both ways, the Applicant should avoid arguments to the effect that one of the embodiments (either the omission or the inclusion of element X) is non-obvious.

  40. 2

    Draw a large circle. Inside at large circle, draw a number of smaller circles. The large circle represents the claimed invention. Let the smaller circles represent prior art.

    I would think that it would be improper to exclude such prior art within the the larger circle by a negative limitations.

    A negative limitation might be proper to narrow the outer boundary of a claim, but not to exclude subject matter within the literal boundaries of the claim.

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