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September 13, 2010

Preamble Ablation

6,986,764 claims "photoselective vaporization of tissue," though that phrase appears only in the preamble. A district court judge found the patent not infringed because the accused product didn't do it. A CAFC majority reversed, figuring the preamble was not a limitation. Judge DYK dissented, suggesting that such claim ablation is a violation.

American Medical System and Laserscope v. Bilitec (CAFC 2009-1323) precedential

Most sharply disputed were the terms in the preambles of the asserted claims: "A method for photoselective vaporization of tissue" and "An apparatus for photoselective vaporization of tissue." 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. Id. at 320-22. The court found support for that conclusion in the patent's discussion of the prior art.

The district court looked at both literal infringement and infringement under the doctrine of equivalents.

The CAFC majority (Judges Bryson, Prost) scratched out the preamble using backhanded reasoning based on case law: if the preamble doesn't add to the claim, it's not effectively part of the claim.

Whether to treat a preamble term as a claim limitation is "determined on the facts of each case in light of the claim as a whole and the invention described in the patent." Storage Tech. Corp. v. Cisco Sys., Inc., 329 F.3d 823, 831 (Fed. Cir. 2003). 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 dissent, Judge DYK suggested a simpler, and truer, metric: make all of a claim count.

Under our precedent, a preamble is construed as limiting "if it recites essential structure or steps, or if it is 'necessary to give life, meaning, and vitality' to the claim," but not if "the claim body describes a structurally complete invention." Over the years our court has struggled to make sense of when a preamble should be construed as limiting. See Bell Commc'ns Research, Inc. v. Vitalink Commc'ns Corp., 55 F.3d 615, 620 (Fed. Cir. 1995) ("Much ink has, of course, been consumed in debates regarding when and to what extent claim preambles limit the scope of the claims in which they appear.").

As the majority itself appears to recognize, we have not succeeded in articulating a clear and simple rule. Majority Op. at 8; see also Patrick J. Flinn, Claim Construction Trends in the Federal Circuit, 572 PLI/PAT 317, 335-36 (1999) (characterizing the preamble limitations test as "opaque" and without a set framework). 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 ยง 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. There is, after all, little to be said in favor of allowing an applicant, in the claim drafting process, to include material in the claims that is not binding. If patentees are allowed to include material in the claim definitions that is not binding, patentees can suggest or imply one position before the U.S. Patent & Trademark Office ("PTO") to secure allowance of the patent on the theory that the preamble is limiting and another, inconsistent position in infringement litigation on the theory that it is not limiting. Principles of fairness thus dictate that the patentee should be required to clearly define the claimed invention's scope. By creating a uniform rule that all preambles are limiting, we would ensure the patentee has the burden of drafting a patent that avoids confusion as to the scope of the claims. As the Supreme Court concluded in Merrill v. Yeomans, 94 U.S. 568, 573-74 (1876), "nothing can be more just and fair, both to the patentee and to the public, than that the former should understand, and correctly describe, just what he has invented, and for what he claims a patent."

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.

Judge DYK argued that, even under the fuzzy guidelines extant, the '764 preamble "was significant," that "the patentee conceded that the term gave life, meaning, and vitality to the claims," and so "must be treated as a claim limitation."

Reversed and remanded.

Judge DYK's dissent may be construed a beckoning to petition for a en banc rehearing.

Posted by Patent Hawk at September 13, 2010 4:48 PM | Claim Construction


"In dissent, Judge DYK suggested a simpler, and truer, metric"


My, that's assuming the answer of the argument, isn't it?

Posted by: Pedantic Pete at September 14, 2010 1:51 AM

Hi Pedantic Pete:

Thanks for reading, and commenting.

I suppose you need a reminder that this a blog, often having gratuitous opinion and sometimes surreal imagery. Irony in full flower, the subject matters of these opinions are likewise often gratuitous and sometimes surreal.

Please note that correlation between case law as covered herein and law as it rationally should be cannot be established, even though the cases presented are regularly of tremendous commercial import. In other words, regardless of the sanity of judicial outcomes, participants are encouraged to keep wagering. As with capitalism in general, the confidence game must go on.

Posted by: Patent Hawk at September 14, 2010 11:04 AM


Rather than "truer", I would have opted for "obvious" - if only to crank the handle.

Posted by: Pedantic Pete at September 14, 2010 12:09 PM