Challenging a KSR substitution rationale

Yesterday's blog post (here) discussed Ex parte Parker, in which the BPAI affirmed an obviousness rejection for an introducer sheath (a medical device used in angioplasty). The Board reached the conclusion of obviousness on two alternative grounds: the Examiner's substitution rationale; and their own "design trade off" rationale.

Yesterday's post focused on how Applicant admissions helped the Board to reach the conclusion of "obvious design trade off." Today I'll discuss the dissenting opinion in Parker, which found error in the Examiner's substitution rationale.

The Examiner offered this rationale for obviousness:

   Horrigan et al. do not disclose the use of a flat wire coil, a round wire coil or a braided wire coil as a reinforcement means. Park et al. teach a catheter section or sheath with equivalent forms of stiffening members or reinforcement for kink resistance, i.e., a flat wire coil, a round wire coil and a braided wire coil.
   It would have been obvious ... to have substituted the wire braid 35 of Horrigan et al. with a braided wire coil, a flat wire coil or a round wire coil as disclosed by Park et al. to have facilitated the manufacture of the catheter or sheath with a diameter suitable for application in an environment of increasingly small diameters.
(Internal citations omitted.)

Now, the strength of the substitution rationale depends on just how equivalent braids and coils really are. The dissent found that the Examiner's premise of equivalency was based on reading statements in the secondary reference (Park) in isolation.

Here's the statement which the Examiner relies on for equivalency:  

[T]he structure of this ribbon coil-based catheter section [in FIG. 5] and the similar variation (224) shown in FIG. 6 using a wire or strand-based unwoven coils (226) are acceptable alternatives to the preferred variation shown in FIG. Nos. 3 and 4.

The dissent says that Park, when read as a whole, merely teaches the interchangeability of braids and coils in the specific context of Park's invention. The dissent says that Park is really about using a super-elastic material for the reinforcing mechanism, where the material changes shape when heat is applied. It's true that Park discloses the reinforcing mechanism can be a coil or a braid. But that doesn't mean that coils and braids are truly interchangeable -– only that the choice doesn't matter for Park's invention because Park's invention is about the material itself.
 
This same point was made (quite elegantly) by the Applicant in the Reply Brief:

[A teaching] that discusses the possibility of using a variety of reinforcements under conditions in which the particular type of reinforcement is of little significance to the teaching at hand, does not provide a skilled artisan with sufficient guidance to arrive at the invention claimed herein ...

A substitution rationale is strongest when it's simple substitution – when switching from braid to coil doesn't make a difference. Without such a teaching – or better yet, with a teaching that says it does make a difference – the rationale is weakened. Here, the Examiner specifically relied on Park to show that coils and braids were equivalent. I say the Applicant was on the right track in attacking this premise. The fact that the majority of judges didn't see it that way doesn't mean it's not a valid argument. I'd say the fact that the dissent was convinced shows the argument has some merit.

BPAI affirms obviousness when Applicant's evidence shows that advantages of claimed feature were known

Takeaway: In an application for a medical device, the Applicant offered declaration evidence explaining why a claimed feature was superior to the feature in the primary reference in the obviousness rejection. The Board found that these admissions supported a conclusion of obviousness, since they demonstrated why a POSITA would substitute the feature missing from the reference to produce the claimed invention. (Ex parte Parker.)

Details:
Ex parte Parker
Appeal 2009009173; Appl. No. 09/815,567; Tech. Center 3700
Decided  March 11, 2011

The technology on appeal involved an "introducer sheath," used in medical procedures like angioplasty. The independent claim on appeal included an inner tube, a wire coil wound around the inner tube, and two outer tubes of differing hardness.

The Examiner rejected under § 103, using a primary reference (Horrigan) that disclosed everything in the claim, except it used a wire braid rather than a wire coil. The secondary reference (Park) disclosed a sheath with "various forms of braid and coil reinforcements," along with "the equivalence of a braid or a coil or a combination of one or more of each for reinforcement of an intravascular device for use in an environment of increasingly small diameters." The Examiner used this to advance the substitution rationale:

It would have been obvious ... to have substituted the wire braid 35 of Horrigan et al. with a braided wire coil, a flat wire coil or a round wire coil as disclosed by Park et al. to have facilitated the manufacture of the catheter or sheath with a diameter suitable for application in an environment of increasingly small diameters.

Before appeal, the Applicant submitted declaration evidence to show that coils and braids are not equivalent or interchangeable. The declarations also explained how computer simulation using finite element analysis had shown the claimed coil was superior to the braid described in the primary reference. The Examiner was not persuaded, so the Applicant appealed.

In the Appeal Brief, the Applicant referred to the statements in the declaration, and explained their significance as follows: 

Clearly, the [finite elements analysis] test showed that the sheath having a coil reinforcement has bending angles at which the sheath having a braid reinforcement would be unusable. This difference can be critical when attempting to position a medical interventional device, such as a stent, at branched or otherwise tortuous area of the vasculature. In many such cases, placement utilizing a coil-reinforced sheath would be successful, while an attempted placement with a braid-reinforced sheath would fail.

The Board agreed with the Examiner's substitution rationale, finding that "the use of a wire coil in an introducer sheath involves the simple substitution of one type of reinforcement (a braid) for another known reinforcement in order to achieve the predictable result of a sheath of small diameter for use in navigating small blood vessels."

The Board noted the Applicant's disagreement with the Examiner on whether or not the secondary reference (Park) taught the equivalence of braids and coils as "alternative types of reinforcement structures utilized in intravascular devices." However, the Board found that even if the Examiner's finding of equivalence was in error, it would be obvious to balance design trade offs to select either a coil or a braid for a reinforcement. The Board based this, in part, on the Applicant's admissions that differences between coils and braids were well understood:

Appellant admits that the properties of and differences between the two types of support structures were known by persons of ordinary skill in the art. See App. Br. 10 (a braid’s torque transmitting ability “is well known to those skilled in the art”); Reply Br. 4 (“Appellant repeatedly emphasized, with both argument and evidence, that those skilled in the art recognize that there is a distinct difference between various types of reinforcements utilized in medical devices.”); Oral Hearing Transcript at 4:16-21 (discussing the high level of knowledge in the art at the time of the invention); id. at 15:12 – 16:5 (same); Spec. 2:1-7 (paraphrasing Parker, col. 1, l. 64 – col. 2, l. 4, and describing that reference as disclosing a sheath with improved kink resistance due to a coil reinforcement). Accepting as fact that ordinary artisans recognized that a coil reinforcement provides predictable and markedly better results than a braid, this, in itself, is a reason to modify Horrigan’s braid-reinforced device. At most, Appellant’s arguments suggest that the Examiner’s proposed modification would require one of ordinary skill in the art to balance certain design trade-offs in selecting the type of reinforcement. However, this does not render the claimed invention non-obvious. Cf. KSR Int’l Co. v. Teleflex Inc., 550 U.S. at 421 (“If [pursuing known options within the ordinary artisan’s grasp] leads to the anticipated success, it is likely the product not of innovation but of ordinary skill and common sense.”)

My two cents: There's a lot going on in this case – seven Office Actions before the case made it to the Board. The Applicant did a lot right. For starters, the Applicant pulled the case from appeal the first time and introduced declaration evidence. The first three responses included a lot of sweeping statements about the art which could be considered "mere attorney argument" by the Board. After that, the Applicant started submitting declaration evidence – a total of four different 1.132 declarations by four different non-inventor experts over the course of the next three years of prosecution.

Today's post focuses on one narrow issue: how the Applicant's argument and evidence about advantages – designed to overcome an obviousness rejection – apparently did just the opposite.

The Applicant fought the same combination of references since the very first Office Action. The substitution rationale was also present since the first Office Action: "mere substitution of one functional equivalent for another" and "selection of any of these known equivalents would provide a cathether section with improved kink resistance as taught by [primary reference.]"

I think the Applicant got stuck, very early in prosecution, on the Examiner's statements about the equivalence of braids and coils. And in refuting the equivalence, the Applicant walked into what turned out to be an obviousness trap. OK, there are differences between coils and braids when used in stents. OK, a coil like the one claimed by Applicant is superior. But if those differences are known (and Applicant admitted they were) then picking the appropriate one can be viewed as a design trade off like those made by engineers every day, as opposed to an invention worthy of a patent. Worse yet, if the superiority of a coil is known (and Applicant's background admitted this in describing another prior art reference) then it's not even a trade off to be investigated by engineers – this known superiority can be viewed as an actual reason to modify the primary reference to use the superior coil rather than the inferior braid.

There's a lot more to this case. There was a dissenting opinion that offers another viewpoint, one which I find compelling. I'll discuss the Ex parte Parker dissent in a future post.

Postscript: The Applicant has appealed the BPAI decision to the Federal Circuit. The assignee is Cook Medical.

New stuff from the PTO

• EFS-Web has been updated to process several types of petitions automatically. See the PTO notice  here. You fill out an online form and the petition is granted in real time by EFS software, without action by a human at the Petitions Office. The list of auto-granted petitions includes Withdraw from Issue and Withdraw as Attorney. Auto granting of Withdraw from Issue is particularly helpful, because under the old procedure the petition was ineffective unless it was "actually received and granted by the appropriate officials before the date of issue."

• The PTO is working on new regulations to change Patent Term Adjustment (PTA) and Patent Term Extension (PTE). (See Federal Reigster notice here.) The biggest change appears to be handling of appeals to the BPAI. PatentDocs reports (here) that under the proposed new rules, reopening of prosecution by the Examiner after a Notice of Appeal results in an increase in term via the PTA or PTE adjustment.

• PharmaPatents reports here on a recent district court lawsuit challenging the PTO's calculation of PTA. This tidbit from the post highlights how PTA is affected by a Non-Compliant Response:
  

  PTA penalty for a "non-compliant" response is particularly harsh, because no matter how long the USPTO takes to notice the alleged defect in the response, and no matter how promptly the defect is corrected, the PTA rules charge Applicants with "delay" for the entire time period from the filing of the original response until the filing of a corrected response.

BPAI reverses rejection based solely on drawings in foreign reference

Takeaway: In Ex parte Ouelette, the BPAI reversed an anticipation rejection that relied exclusively on a drawing in foreign language reference. "The figures are so small and blurred as to be unreadable so that the exact position and operation of the formers 7 cannot be determined. The Niwa written disclosure does not provide assistance in this regard."

Details:
Ex parte Ouelette
Appeal 200700807; Appl. No. 10/298,456; Tech. Center 3700
Decided  May 1, 2008

The Applicant claimed specific structures of a conveyor, including a diagonally oriented lower guide surface and an opposing diagonally oriented upper guide surface, where the lower guide surface slopes upwardly and the upper guide surface slopes downwardly. [Paraphrase of claim 6.]

The Examiner rejected under § 102(b) using only the drawings from a Japanese patent (shown below). In the Final Office Action, the Examiner alleged that the patent showed "opposing upper and lower lateral guides 7 that are inclined toward each other (see Figure 1 and compare Figures 2-4) to position the film on the sides of the objects." [Reference numbers 7 shown in red below.]

On appeal, the Applicant made several distinctions. One of the distinctions was that "the only diagonally oriented edges of the members 7, 9 disclosed by the Japanese publication overlap each other, and do not oppose each other."

In the Response to Argument section of the Answer, the Examiner explained that the Applicant had misinterpreted the final rejection:

It should first be noted that element 9 is not a guide surface, as mentioned by applicant, and it was not referred to in the Final Rejection but as shown in figure 1 of the publication 9 is plate positioned under the film (also see Figures 2-4). The rejection referred to the two guide surfaces 7 that are inclined upward and downward to create the film folds.

The Examiner then clarified the rejection in the body of the Answer:

The [guides] are vertically opposed each other in that they start out in the upstream position in spaced and opposite relations, i.e. upper and lower positions, and end up in an overlapped position and opposite each other, i.e. lower and upper positions, as they pass each other to perform the folding of the two edge of the film. Furthermore, the guide surfaces can be considered to be horizontally opposed each other in that they are facing each other in parallel planes.

The Applicant filed a Reply Brief, noting that:

These comments [in the Answer's Response to Arguments section] point out the ambiguousness of the Japanese reference. In Figure 2 of the reference, it appears that the reference No. 9 is being directed to one of the four angled elements arranged adjacent the four corners of the object 4. One of the angled elements, the element adjacent the upper right-hand corner of the object 4 shown in Figure 2 is labeled with the reference No. 7. The other three angled elements apparently are not labeled. The drawing figures of the reference are so ambiguous, it is not clear as to whether all four of the angled elements are identified by the reference No. 7.

The Applicant further argued that "in view of the ambiguousness of the Japanese reference alone, the reference is not a valid reference for an anticipation rejection."

After the Reply Brief was filed, the Examiner provided a translation of the Japanese reference for the record.

In the Decision on Appeal, the Board made the following Finding of Fact:

The figures do not clearly depict the other elements of the device. Specifically, the figures are so small and blurred as to be unreadable so that the exact position and operation of the formers 7 cannot be determined. The Niwa written disclosure does not provide assistance in this regard.

 The Board reversed the rejection, explaining that:

Any conclusions about the position and function of the formers 7 can only be made by speculation" A reference relied on to prove unpatentability must be so  clear and explicit that those skilled in the art will have no difficulty in ascertaining its meaning. See In re Turlay, 304 F.2d 893, 899 (CCPA 1962).

My two cents: I don't handle a lot of mechanical cases, but two things seem clear to me. One, spatial and positional relationships between components are often key to the claims. Two, drawings are often very important in showing these relationships, but sometimes a written description is helpful in explaining the drawings. Here, the drawing included lots of features, which made it hard to see what the reference numbers pointed to, and there was no translation provided before appeal. So it makes sense to me that the Board found this rejection deficient.

I'm disappointed that the Board didn't even mention that the Examiner didn't provide a translation until after the Reply Brief. The Board should have slammed the Examiner for this oversight. 

Then again, don't expect the Board to do your work for you. The Applicant should have demanded a translation of the Japanese reference, citing MPEP 706.02. You can't really force the Examiner to comply, but it can't hurt, right? See my post "Dealing With Foreign References".

BPAI reverses obviousness because invention solved different problem than either reference

Takeaway: The BPAI reversed an obviousness rejection when the claimed invention solved one problem, yet the primary reference solved another problem, and the secondary reference solved yet another. (Ex parte Young, March 29, 2011.)

Details:
Ex parte Young
Appeal 2010010001; Appl. No. 12/103,325; Tech. Center 3700
Decided  March 29, 2011

The claimed subject matter was directed to a medical device, such as a feeding tube. Claim 1, a representative claim on appeal, read:

1. A medical device configured for dynamic movement through a body canal toward an interior target site and removal therefrom, said device comprising
     an elongate tubular member having a plurality of distal projections disposed on an exterior surface thereof,
     said projections extending outwardly from the exterior surface of the tubular member a distance sufficient to engage an interior surface of the body canal during bodily contractions therein,
     said distal projections being configured so as to promote ingress of said device in response to said contractions,
     at least some of said projections being formed of a composition that is soluble under bodily conditions at said body canal.

An example embodiment is shown below, with distal projections 16.

The Examiner rejected claim 1 as obvious, alleging that the primary reference (Reydel) taught a medical device with distal projections as claimed, except for the soluble composition. The Examiner relied on the secondary reference (Anders) for teaching a catheter having a portion that is formed of a composition soluble under bodily conditions. The Examiner alleged that using Anders' soluble composition to form Reydel's distal projections would be obvious "to provide a composition that will dissolve in bodily fluids" as taught by Anders. The Examiner further alleged that "it is within the general skill of a worker in the art to select a known material based on its suitability for the intended use as a matter of obvious design choice."

The Appellant argued that Reydel's tube differed from the claimed tube because although the projections are useful for inserting the tube, the projections impede removal of the tube. The Applicant argued that the claimed invention improves on Reydel's tube by providing a mechanism for removing the projections once the tube is placed: the projections dissolve. Thus, the invention "addresses difficulties that may be encountered when attempting to withdraw the tube." The secondary reference, Anders, disclosed a needle with a soluble tip. But the problem addressed by Anders was much different: protecting healthcare workers from needle sticks.


The Board agreed with the Applicant and reversed the obviousness rejection. The Board found that "the Examiner did not establish a reason based on the evidence in the record for combining Reydel with Anders to result in a medical device comprising projections formed of a composition that is soluble in a body canal."

The Board first noted the problem addressed by, and the solution provided by, the claimed invention: unidirectional projections that promote ingress but then dissolve to eliminate an impediment to egress. The Board then contrasted this with the problem and solution of Reydel – bidirectional projections that assist in ingress and remain during egress without causing trauma. Finally, the Board noted that Anders addressed yet another problem, needle stick, that can occur outside the body after removal of the device. The Board concluded that "the Examiner has not shown through evidence that, at the time of the invention, it would have been desirable to have a medical device including a tubular body with exterior projections that are present only during ingress, much less to use dissolvable flaps as a solution."

My two cents: I haven't seen many cases where the Board used this sort of "problem" analysis to decide obviousness.

The Board focused on the teachings of the references as a whole rather than just the specific features used by the Examiner. The Board found that the "bidirectional" projections in Reydel functioned differently than the Applicant's projections, and used this in finding non-obviousness. This argument wouldn't have gone far in an anticipation rejection. First of all, the claims didn't recite the unidirectional behavior, so the feature is irrelevant. Second, the fact that a reference teaches more than is claimed – Reydel's projections were flexible and thus "bidirectional" – is irrelevant to anticipation. Yet the Board did looked to these aspects of Reydel in deciding whether or not a POSITA would combine Reydel with Anders.


The Board did not comment on the Examiner's "obvious design choice to select a suitable material" rationale. Perhaps the factors which the Board focused on outweighed the suitable material rationale. In other words, it's obvious to select a suitable material unless there are reasons why it's not obvious, such as those the Board found.

The Board also didn't comment on the Examiner's circular rationale for combining: it would be obvious to add  claimed feature A (soluble projections) to the primary reference to produce the result provided by feature A (soluble projections).

Blog posts that pose interesting questions about claim scope

Blog Posts that pose interesting questions about obscure aspects of claim scope:

• IPBiz wonders if including a claim in a provisional can lead to prosecution history estoppel?
• PatentPoints wonders if including reference numbers in a claim can narrow claim scope?

I haven't researched these topics, so don't know the answers, or if clear answers even exist. I read a lot of case law, and I haven't come across these topics before.