PTO Claim Construction: “Flexible Foam” Is Not “Rigid Foam That Is Flexible When Crushed”

In re Buszard (Fed. Cir. 2007)

The Buszard application is directed to a flame retardant composition that includes a flexible polyurethane foam base. The PTO Patent Appeal Board rejected Buszard’s patent application as anticipated by a prior patent.

On appeal, the CAFC reversed — Judge Newman penned the opinion that focused on the PTO’s practice of giving claims their ‘broadest reasonable interpretation.’

“Buszard’s specification and claims specifically state the requirement of a flexible polyurethane foam…. No matter how broadly “flexible foam…” is construed, it is not a rigid foam…. The [cited prior art] reference describes only a rigid foam reaction mixture that produces a rigid product. Only by mechanically crushing the rigid product into small particles is it rendered flexible, as a rock can be mechanically crushed to produce particles of sand. This description cannot reasonably be construed to describe, and thus to “anticipate,” the flexible foam product of a flexible foam reaction mixture. We agree with Buszard that it is not a reasonable claim interpretation to equate “flexible” with “rigid,” or to equate a crushed rigid polyurethane foam with a flexible polyurethane foam.”

Interestingly, Judge Newman’s claim construction intertwines analysis of the claim language with analysis of the scope of prior art disclosure.  Although the PTO may give an applicant’s claims broad interpretation — the scope of the prior art cannot extend beyond its disclosure.

Judge Prost dissented. In Prost’s view, any ambiguities in patent claim terms should be construed against the patentee during prosecution of the patent. That approach avoids the usual ‘guessing game’ of Phillips-style claim construction and it is quite easy for an applicant to make clarifying amendments to claim language.  

15 thoughts on “PTO Claim Construction: “Flexible Foam” Is Not “Rigid Foam That Is Flexible When Crushed”

  1. Flexible and rigid foams are terms well used in the art and really don’t require explanantion more than the terms black or white. Thus, Newman is right, again.

  2. Hello Art. Hello Kramer.

    This is one where just about everybody got it wrong because there was no “evidence” in the case. Judge Prost was correct to criticize the failure of the applicant to submit “evidence” as to how an ordinary artisan would reasonably interpret the the claim language (note that it says “foamed” –past tense). However the Board was equally wrong in arriving at a decision with no factual basis to back its decision. The case was remanded. That means it returns to the examiner. I suspect that all involved will clean up their acts and clarify the meanings of the claim terms.

  3. “Hello Newman.” “Hello Jerry.”
    Judge Newman got it wrong again. Most attorneys still do not understand that claim interpretation during ex parte examination is different from claim interpretation during litigation! My guess is that those of you who think this is the right decision also can’t explain the difference between the two.
    Also, remember that is a claim for a product, not a process. Therefore if the “thing” is anticipated at any time, its anticipated!
    Judge Prost got it right.

  4. For an EPO practitioner, another fascinating glimpse into the strange world of US patent jurisprudence. My thoughts:
    1) Split the claim into two parts, relative to the disclosure of Eling, and you get: characterized in that the reaction mixture is flexible. Now, the essential core function of a claim is to define the line between what’s within it and what’s not. Now, when is something rigid and when is that thing flaccid? It all depends on your viewpoint, doesn’t it? The patent owner might well have a different and more optimistic view than the accused infringer. Litigation, here we come. When it comes to PU foam reaction mixtures, some might be more flexible than others, but isn’t there a continuous progression of rigidity, from fully flaccid to extremely rigid, with all intermediate degrees of rigidity in between? I was always taught that adjectives have no place in clear claims. When novelty hangs on an adjective of degree like “flexible” the claim is grotesquely unclear, and deserves to be swiftly despatched to oblivion.
    2) Being a former chemical patent attorney (Newman) might be a disadvantage. Such a person would well know that there is a qualitative difference between, say, HD and LD PE (or between rigid and flexible PU foam) but that’s no help when the accused infringement lies somewhere in between “high” and “low”. We know where England ends and France begins (there’s water in between) but not where Europe ends and Asia begins.
    3) Anyway, aren’t ALL foam reaction mixtures “flexible”, including those prior art ones used in the foam blowing process of Eling? It’s only when they are made into foam that you can say whether or not they are rigid (the foams that is, not the starting reaction mixture).

  5. big hairy rat states: “The result may be right but the analogy to rock and sand is not apt. Rock after all is ‘flexible’ in the sense that a slab of rock can be bent under sufficient force – just not very far before it cracks.”

    Dude, you must be smoking the same thing that Prost was smoking? In Prost’s case, it resulted in mental masturbation in the “legal” sense. In your case, it resulted in mental masturbation in the “scientific” sense.

    Frankly, I doubt that “flexible” is the first word that comes to mind when someone mentions “rock.”

    BTW (a little mental masturbation on my part), the only flexible “rock” that I know of is thin sheet mica.

  6. The result may be right but the analogy to rock and sand is not apt. Rock after all is ‘flexible’ in the sense that a slab of rock can be bent under sufficient force – just not very far before it cracks. Absent some official definition of “rigid” and “flexible” in terms of bending resistance and ductility the court should have simply relied on the common, popular, meanings of the words and not resorted to analogies that create more smoke than light.

  7. While quite lawyerly logical, Prost’s dissent is devoid of good judgment.

    Under Prost’s theory, the PTO can effectively reject claims directed to a toaster as anticipated by art describing a bread truck because both toasters and bread trucks emit heat and hold bread! Everyone knows a toaster is not a bread truck. Under Prost’s theory, nevertheless, the inventor is supposed to draft a patent application to account for the fact that a toaster is not a bread truck!

    Gotta love Newman, the CHEMIST!

  8. As a practicing chemist, I’m appalled by some of the arguments that were made against this application: “The Solicitor proposed at oral argument that when a rigid foam is mechanically crushed, the chemical bonds are broken and the product is the same as the flexible product of a flexible foam reaction mixture. There was no rejection on this ground, there is no evidence or argument to this effect in the record, this theory was not mentioned by any examiner or in the Board’s opinion, and it appears to be contrary to science. This theory was proposed without support or citation, and without opportunity for Buszard to refute it. It is not sufficiently creditable to warrant further consideration.” Yes, there is no science to support this and there cannot be any such science.

    And from the dissent: “The only enlightenment Buszard provides regarding the meaning of “flexible polyurethane foam reaction mixture” is a single page from the Kirk-Othmer Encyclopedia of Chemical Technology, which generally describes the differences between “flexible foam” and “rigid foam.” Nowhere in the record, however, is there any evidence regarding how a person of ordinary skill in the art would interpret the phrase “flexible polyurethane foam reaction mixture.” The Kirk-Othmer is an authoritative reference in chemistry. I get the feeling that Judge Prost thinks that this is just some junky monograph that someone self-published or a similar publication of dubious value. To say that it is at odds with a or does not describe a PHOSITA is incorrect.

  9. J. Prost’s dissent is ridiculous. She chastises the applicant for not amending around the PTO’s interpretation of the prior art. Of course, that interpretation wasn’t even presented by the PTO until one of the associate solicitor’s was questioned during the hearing.

    This is typical PTO “broadest interpretation.” “Well, everything has some degree of flexibility.” Somebody needs to inform the PTO that the requirement is broadest reasonable interpretation.

    Is it any wonder that the examining corps makes such nonsensical interpretations of the prior art? It flows from the top.

  10. I just had a thought. They are now calling it the Patent Appeal Board, with no reference to interferences. Is this an indication the PTO and Congress would like to go to first-to-file, eliminating the need for interferences?

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