Judge Dyk Suggests En Banc Review of CAFC Preamble Law

Yesterday the United States Court of Appeals for the Federal Circuit issued a precedential opinion in American Medical Systems, Inc. v. Biolitec, Inc. The decision dealt with the scintillating topic of whether a term in the preamble of the claim is limiting.  The district court determined it was, and so did the dissenting Judge on the panel, Judge Dyk.  The majority of the panel (Judges Bryson and Prost), however, determined it was not limiting, and I think correctly reached that decision.  What is of particular interest, however, is the fact that Judge Dyk in dissent came out and said that it was time for the Federal Circuit to en banc decide the appropriate standard for when the preamble is limiting because any fair reading of Federal Circuit “preamble jurisprudence” is difficult to reconcile.  While I disagree with Judge Dyk on this case, I am all for settling of the law and in areas where there are conflicting panel decisions, which is pretty much everywhere.  The Federal Circuit should aspire to certainty wherever possible.  After all, that was why the Court was formed in the first place.

The invention in question, which is embodied in U.S. Patent No. 6,986,764, can be used to treat Benign Prostatic Hyperplasia (“BPH”), a condition in which growth of the prostate gland restricts the passage of urine out of the bladder and through the urethra. As many men can tell you, BPH or any problems with your prostate can significantly, and negatively, impact quality of life. Prior art tissue vaporization systems were inefficient when used with continuous irrigation, and they frequently caused side effects including residual tissue coagulation, which led to swelling, transient urinary retention, and infection. The ineffectiveness of the prior art systems was due in part to their use of longer wavelengths of laser radiation, such as 2100 or 1064 nanometers (“nm”).

The inventors of the ’764 patent determined that the use of a high amount of energy delivered to a given volume of tissue would result in increased vaporization efficiency while minimizing residual coagulation. Accordingly, the patent was directed to various methods and devices for achieving high volumetric power density for tissue vaporization, by manipulating variables such as wavelength, output power, beam quality, irrigant composition, and distance between the optical fiber and the tissue.

Following a Markman hearing, the district court issued an order construing several key terms in the asserted claims, chief among them for purposes of the appeal was the disputed term “photoselective vaporization,” which was found only in the preamble of the claims. The illustrative claim selected by the majority was claim 31, which reads:

A method for photoselective vaporization of tissue, comprising:

delivering laser radiation to a treatment area on the tissue, the laser radiation having a wavelength and having irradiance in the treatment area sufficient to cause vaporization of a substantially greater volume of tissue than a volume of residual coagulated tissue caused by the laser radiation, wherein the delivered laser radiation has an average irradiance in the treatment area greater than 10 kiloWatts/cm2 in a spot size at least 0.05 mm.

The plaintiffs argued that the preamble language simply describes the invention as a whole and should not be construed as a limitation of any of the asserted claims. The district court, however, ruled that the repeated use of the phrase “photoselective vaporization” in the specification and claims indicated that “photoselective vaporization” is a “fundamental characteristic” of the invention, albeit not its central innovative feature. As a result, the district court construed the term “photoselective vaporization” to mean “using a wavelength that is highly absorptive in the tissue, while being absorbed only to a negligible degree by water or other irrigant.”

In light of the district court’s claim construction ruling, Biolitec moved for summary judgment of noninfringement. The district court granted Biolitec’s motion and began by noting certain undisputed facts concerning the properties of 980 nm laser light (as in the accused product), as compared with 532 nm laser light (the wavelength of the ’764 patent’s preferred and commercial embodiment). The district court also observed that Biolitec’s accused device operates by placing the device in direct contact with the target tissue so as to prevent absorption of the energy by the water irrigant. In light of those facts, the court concluded that “[w]hen compared to 532 nm laser light, 980 nm laser light is more than negligibly absorbed by the water irrigant” and thus did not satisfy the “photoselective vaporization” limitation of the ’764 patent, as the district court construed it. Based on this determination the district court determined that there was no literal infringement.

Judge Bryson, writing for the majority, started the substantive analysis discussing the law relative to whether a preamble term is considered limiting. Judge Bryson wrote:

While there is no simple test for determining when a preamble limits claim scope, we have set forth some general principles to guide that inquiry. “Generally,” we have said, “the preamble does not limit the claims.” Allen Eng’g Corp. v. Bartell Indus., Inc., 299 F.3d 1336, 1346 (Fed. Cir. 2002). Nonetheless, the preamble may be construed as limiting “if it recites essential structure or steps, or if it is ‘necessary to give life, meaning, and vitality’ to the claim.” Catalina Mktg. Int’l, Inc. v. Coolsavings.com, Inc., 289 F.3d 801, 808 (Fed. Cir. 2002), quoting Pitney Bowes, Inc. v. Hewlett-Packard Co., 182 F.3d 1298, 1305 (Fed. Cir. 1999). A preamble is not regarded as limiting, however, “when the claim body describes a structurally complete invention such that deletion of the preamble phrase does not affect the structure or steps of the claimed invention.” Catalina, 289 F.3d at 809. If the preamble “is reasonably susceptible to being construed to be merely duplicative of the limitations in the body of the claim (and was not clearly added to overcome a [prior art] rejection), we do not construe it to be a separate limitation.” Symantec Corp. v. Computer Assocs. Int’l, Inc., 522 F.3d 1279, 1288-89 (Fed. Cir. 2008). We have held that the preamble has no separate limiting effect if, for example, “the preamble merely gives a descriptive name to the set of limitations in the body of the claim that completely set forth the invention.” IMS Tech., Inc. v. Haas Automation, Inc., 206 F.3d 1422, 1434-35 (Fed. Cir. 2000).

In light of this law, Judge Bryson, who was joined by Judge Prost, concluded that the preamble language in the asserted claims of the ’764 patent did not constitute a limitation of the claims. The majority reached this conclusion for three separate reasons, with the third being considered the most persuasive by the Court. The reasons were:

  1. Upon review of the prosecution history there was no reason to believe that the inventors added the phrase “photoselective vaporization” in order to distinguish their invention from the prior art. In fact, the examiner’s primary reason for approval was the claims’ use of high power densities to vaporize tissue without causing significant residual tissue damage.
  2. The preamble term “photoselective vaporization of tissue” did not provide a necessary antecedent basis for the term “the tissue” in the bodies of each of the independent claims.
  3. The descriptor “photoselective” did not embody an essential component of the invention. Instead, Court determined that the term “photoselective vaporization” was simply a descriptive name for the invention defined in the claims.

Judge Dyk filed a dissenting opinion in the case and specifically pointed out that the Federal Circuit’s case law relative to whether the preamble is limiting is extremely unclear. He also suggested that it would be appropriate for the entire Federal Circuit to consider this matter en banc. Judge Dyk wrote:

As the majority itself appears to recognize, we have not succeeded in articulating a clear and simple rule. As a result of the lack of clarity as to whether a preamble should be construed as limiting, our case law has become rife with inconsistency, both in result and in the articulation of the test. As the leading treatise on patent law observes, “the decisions are difficult to reconcile.” Donald S. Chisum, Chisum on Patents § 8.06[1][d] (2010).

It seems to me that a rule recognizing that all preambles are limiting would make better sense and would better serve the interests of all concerned…

Neither the Supreme Court nor our court sitting en banc has ever addressed the preamble limitation issue. I think the time may have come for us to eliminate this
vague and confusing rule.

In reading Judge Dyk’s dissent it is clear he simply disagrees with the majority’s conclusion, although his point about the uncertainty of the law relative to the preamble is well taken. Nevertheless, I disagree with Judge Dyk’s analysis as it pertains to this particular case. In his dissent he writes:

The applicant took considerable care to add new matter to the specification describing and defining photoselective vaporization. The term appears in the title of the patent (once), the abstract (once), the Field of the Invention section (twice), the Summary of the Invention section (twice), and the Detailed Description section (once). For example, the Field of the Invention section states: “The present invention relates generally to laser treatment of soft tissue, and more particularly to photoselective vaporization of the prostate PVP, and to photoselective vaporization of other tissue.”

The “new matter” Judge Dyk speaks of is matter that was inserted for the first time as part of a continuation-in-part, so not the type of “new matter” that might be attempted to be snuck into an application contrary to the prohibition against new matter. Confusing I know, but the term “photoselective vaporization” arrived at the time of the filing of the continuation-in-part, so technically is was not “new matter,” but rather viewed best as additional matter that received the benefit of the filing date of the continuation-in-part.

With that out of the way, allow me to point out that what Judge Dyk seems to be focusing on is the use of the term photoselective vaporization as a characterization. I see no evidence that it is being used as an element or limitation, and agree with the marjority that the term is nothing more than a characterization. It is a way to refer to the totality of the invention claimed, not a particular aspect, element or limitation of the invention.

I would also like to take issue with Judge Dyk’s statement that it would simply be easier, and better, to say that anything in the preamble is limiting.  Yes, that would certainly be easier and probably a better approach than the nebulous standard presently in place, but I doubt that would be to the Supreme Court’s liking given they seem to detest bright line rules, even when they make sense.  I also protest such an approach because that has, as far as I can tell, never been the law, or at least not at any time during my practice career.  So regardless of whether it is a better test it absolutely should not be applied retroactively to affect those rights obtained under the belief that what is in the preamble is not limiting.

The Federal Circuit has been famous over the years for announcing rules and then pretending that the rule is not new and has always been that way.  The reality is this stuff is not academic, and changing for the sake of change does nothing to infuse certainty.  All it proves is that the system can be certain right up until the mind of the Judges are changed, and then the law is made certain in a different direction.  Such pendulum swinging is never appropriate when dealing with property rights, and would be objectively bad for the millions of patents obtained under a regime that is directly contrary to the stated preference of Judge Dyk.


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Join the Discussion

7 comments so far.

  • [Avatar for Blind Dogma]
    Blind Dogma
    September 15, 2010 02:18 pm

    Simple – read the claim. construe the claim. if the terms in the preamble are necessary (for the short list of reasons listed in the decision), then the terms in the preamble are limiting. If not, then not.

    People, is this really that difficult to understand?

    I’m seeing a lot of fluff that is totally besides the point.

    step back – a clear example of breathing life (101).

    Dyk is stirring up a nest of inconsequence. Patent law has lots of areas that are not easy. Deal.

    As to whether an invention is statutory as a machine, a manufacture, or a composition of matter, when has anybody ever cared which of the three a particular claim was?

    Not to nitpick, but you missed a statutory class, and the answer is an emphatic yes – just ask Nujiten.

  • [Avatar for IANAE]
    September 15, 2010 01:20 pm

    If you can’t tell from the body of the claim whether the claimed invention is a method or a “solid”, the claim is seriously defective.

    As to whether an invention is statutory as a machine, a manufacture, or a composition of matter, when has anybody ever cared which of the three a particular claim was?

    If you ask me, the only reason to put anything other than environment in a preamble is because you’re after deliberate ambiguity – a limiting preamble before the examiner and a non-limiting one before the court, increased uncertainty and litigation costs for the infringer, or somesuch. The patent system should not tolerate that. If you want it limiting, put it in the claim body. If you don’t want it limiting, leave it out. If you want ambiguity, re-read 35 USC 112.

    Anyway, the term “photoselective” without more is probably broad enough to include just about anything that would otherwise infringe the claim body. If a particular type of photoselectivity is intended, that should definitely be in the claim body.

  • [Avatar for step back]
    step back
    September 15, 2010 12:40 pm

    To say that the preamble doesn’t count is the height of lunacy.
    Firstly, the preamble usually informs as to whether the thing being claimed is a process, machine, manufacture or composition of matter. There are times when one cannot tell by looking only at the body of the claim.

  • [Avatar for Gene Quinn]
    Gene Quinn
    September 15, 2010 10:33 am


    Maybe we will need to agree to disagree on whether this is limiting or not, but we can certainly agree that the preamble law is indeed a mess, which no doubt allows reasonable people to find support for either side in this dispute. I, however, would have gone with the majority on this one.

    I also agree with you that the preambles should be a short as possible to avoid any problems.

    With something this important (it is fundamental for crying out loud) the CAFC should have an easy to understand and apply test. My fear is that such a test would negatively affect rights obtained under the belief that the preamble is not typically limiting.


  • [Avatar for Michael]
    September 15, 2010 08:48 am

    Why not make the bright-line rule be that you must have antecedent basis for the preamble? Any word except EG’s “a composition”, “a method”, “a device” must either be defined (and therefore limiting) or objected to by the examiner (and therefore will either be removed or defined by amendment or argument, and therefore limiting). If it is possible to have an argument over whether the preamble will be limiting or not, then it should be taken care of during prosecution, not litigation.

  • [Avatar for EG]
    September 15, 2010 08:17 am


    We may have to “agree to disagree” on this one. I frankly agree with the dissenting opinion on this one. The case law on when preambles are “limiting or not” is one royal mess. (I know because I had to do research on this issue for an actual lawsuit.) Most significantly, treating the preamble as non-limiting conflicts with the All Elements/All Limitations Rule. The only time treating the preamble as non-limiting makes any sense is if that preamble is a statement of intended use (e.g., “An electrolyte composition”), in which case the preamble is meaningless “window-dressing” for both validity and infringement purposes.

    Also, the preamble is usually considered limiting if it provides antecedent basis for terms present in the body of the claim. In claims as issue here (e.g., Claim 1), the preamble “photoselective vaporization of tissue” provides antecedent basis for two terms used in the body of those claims (“the tissue” and “vaporization”). In fact, if the preamble “photoselective vaporization of tissue” isn’t considered limiting in these Claims, I wonder why those Claims should go down under 35 USC 112, 2nd paragraph as being indefinite.

    As a practice matter, I also think you’re asking for trouble to use any more than a bare-bones such as “a composition,” “a method,” “a device,” etc. Why subject yourself to what amounts to a coin flip? I now rarely use additional language in the preamble, and usually then only because I need to state the “environment” that the invention is used in.

  • [Avatar for Anon]
    September 14, 2010 08:00 pm

    The echo of “Brightline” rings from One First Street NE and Maryland Avenue.