Claim Construction in the Abstract

By Dennis Crouch

Typhoon Touch Tech. v. Dell, Lenovo, Toshiba, Fujitsu, Sand Dune Ventures, Panasonic, Apple, HTC, and Palm (Fed. Cir. 2011)

Touch screen technology has taken-off as an important element of consumer electronics. Typhoon’s US Patent Nos. 5,379,057 and 5,675,362 cover various embodiments of a “portable keyboardless computer system” with a “touch-sensitive screen.”

Typhoon appealed an E.D. Texas ruling that its patents were invalid and not infringed. The appeal focused on the claim construction that served as the basis for both invalidity and non-infringement. The appellate decision is notable for the detached process that the court used to consider claims elements at issue. The opinion never discussed the crux of the invention or its contribution to the art and instead simply looked to the disputed claim terms and the relation of those terms in the specification (as required by Phillips v. AWH).

This week, I participated in a roundtable discussion at Yale Law School sponsored by the Kauffman foundation and by Yale’s Information Society Project (ISP). A substantial amount of the discussion focused on problems stemming from our current claim construction process and our ongoing focus on claim language as opposed to invention or its contribution to the art.

For patent attorneys prosecuting patents, the claims are often seen as equivalent to the invention. The new patent act supports that definition by shifting focus away from the invention and instead onto the “claimed invention.” Thus, the new § 102(a)(1) asks whether “the claimed invention was patented, described in a printed publication, or in public use, on sale, or otherwise available to the public before the effective filing date of the claimed invention.” The new statute’s sole focus on invention as claimed is largely just a codification of fairly well accepted Federal Circuit precedent without much thought of the consequences. Of course, broad subject matter eligibility described in State Street Bank and the TSM test for obviousness were, until quite recently, well accepted Federal Circuit precedents as well. In the past few years, the Supreme Court rolled-back the clock on those issues – returning focus to pre-1982 case law. For “invention” however, the new statute appears to lock-in the claimed-invention as the ongoing focus of patent law.

Judge Kimberly Moore highlighted this issue in her recent dissent from the court’s denial of en banc rehearing of Retractable Technologies, Inc. v. Becton, Dickinson and Company (Fed. Cir. 2011). In that opinion, Judge Moore noted that the approach of the panel decision in Retractable is evident of a major divide amongst Federal Circuit judges as to whether the inventor’s contribution to the art – “what the inventor actually invented” – should be considered in the claim construction process.

This week, my patent law students each argued a mock-Markman hearing – revisiting the facts of Nystrom v. Trex and arguing over whether Ron Nystrom’s claimed decking “board” should be limited to cover only to wood cut from a log. That litigation was interesting because it involved five different court decisions on the proper construction of the term. The final appellate decision narrowed the term’s meaning in a way that allowed Trex’s composite planking to avoid infringement.

Claim construction has become a fundamental aspect of every patent case – even to the extent that Section 101 patentable subject matter decisions turn on the meaning bestowed upon particular claim terms. For patent attorneys, all of this focus on claim meaning puts more pressure on the drafting of the claims and the specification. The sad thing about Nystrom’s patent is that he would have easily won the case if the patent attorney who drafted the application had thrown-in language indicating that a “board” could be made of various materials, not just wood cut from a log. This counterfactual conclusion is sad for Nystrom as the inventor, but it is also sad that such a major weight is placed on non-inventive boilerplate language. In my mind, the importance of claim construction should push the USPTO to do a better job of ensuring that the terms of issued patents are well defined.


The Typhoon decision is also notable in the way that the court narrowly interpreted functional claim limitations. As background, Typhoon’s claim was directed to a “computer” that included various elements including a “memory for storing [a] data collection application.” Typhoon argued its claimed invention only required that the memory be capable of storing the data collection application. However, the District Court Judge Davis and Federal Circuit agreed that the proper construction required that memory actually be used for storing the data collection application. In so holding, the courts looked to the specification and found that the described embodiments all had memories that actually included the application rather than just the capability.


Finally, the court looked at Typhoon’s “Means for cross-referencing” limitation. The district court held that limitation invalid as indefinite under 35 U.S.C. § 112 because the specification did not include an algorithm adequate to provide sufficient structure for the means-plus-function limitation, citing Aristocrat Technologies Australia PTY Ltd. v. International Game Technology, 521 F.3d 1328, 1334 (Fed Cir. 2008). On appeal, the Federal Circuit rejected that conclusion – finding that the specification did disclose a cross-referencing algorithm in plain language in the text of the specification. The court went on to write that “computer code is not required to be included in the patent specification.” Rather, what is required is disclosure so that one of ordinary skill in the art would recognize the structure as linked to the claimed function.


  • Judge Newman wrote the court opinion and was joined by Chief Judge Rader and Judge Prost;
  • The Appellant-Patentee is represented on appeal by Charles Wolfe (Blank Rome);
  • Ed Reines (Weil Gotshal) and Joe Re (Knobbe) were co-lead-counsel for all the appellee-defendants. Briefs were also signed by attorneys at K&L Gates, Baker Botts, Amster Rothstein, Perkins Coie, Covington & Burling, and Malloy & Malloy, as well as Eric Albritton from the Albritton firm.

Federal Circuit Again Declines to Revisit Cybor

By Jason Rantanen

Retractable Technologies, Inc. v. Becton, Dickinson and Company (Fed. Cir. 2011) (CAFC en banc denial) Download 2010-1402 en banc order
Before Rader (dissenting), Newman, Plager, Lourie, Bryson, Linn, Dyk, Prost, Moore (dissenting), O'Malley (dissenting), and Reyna.

As in the past, the Federal Circuit has again expressly declined an invitation to revisit its 1998 en banc holding in Cybor Corp. v. FAS Techs., Inc., 138 F.3d 1448 that claim construction is reviewed de novo.  Once again, however, that decision was not without dissent.  Both Judge Moore, joined by Chief Judge Rader, and Judge O'Malley wrote to express their view that Cybor should be revisited. Professor Tun-Jeng Chiang expresses his views on this issue below.

In addition to recommending that the court reconsider the issue of deference, Judge Moore's dissent emphasizes the problematic nature of claim construction review by the Federal Circuit itself: on the one hand, "[c]laim construction is the single most important event in the course of a patent litigation"; on the other, "our rules are still ill-defined and inconsistently applied, even by us."  Moore dissent at 1.  This problem is especially acute in Retractable Technologies: "Retractable simply cannot be reconciled with our en banc decision in Phillips."  Id. at 4.  Here, Judge Moore asserts, the majority applied its own approach to claim construction, not that of Phillips, "[c]hanging the plain meaning of a claim term to tailor its scope to what the panel believes was the actual invention."  Id. at 6.  This is not an isolated instance, Judge Moore points out, but is a common practice that points to a fundamental split on the court about the nature of claim construction: a disagreement over whether claim scope should be limited to "what the inventor actually invented" or instead construed according to the plain meaning to one of skill in the art, a meaning that may be informed – but is not dictated – by the specification.

Note: In  support of her view that the Federal Circuit's own claim construction is ill-defined and inconsistently applied, Judge Moore cited the views of several commentators who "have observed that claim construction appeals often lead to frustrating and unpredictable results for both the litigants and trial courts," including Dennis's post on the panel decision and Hal Wegner's post on Arlington Industries v. Bridgeport Fittings on IP Frontline

Guest Post by Tun-Jen Chiang: Functionalism versus Faux Formalism at the Federal Circuit

Guest Post by Tun-Jen Chiang, Assistant Professor of Law, George Mason University School of Law

One of the longstanding myths about the Federal Circuit is that it is formalist.  This is usually levied by academics as a criticism, but no one does more than the Federal Circuit itself to spread the myth.  For judges, being labeled as a jurisprudential machine is a badge of honor.  Thus, even where their true motivation is clearly policy-based, judges invariably couch their opinions in legalistic terms.

The recent dissents from en banc rehearing in Retractable Technologies, Inc. v. Becton, Dickinson & Co. provide perfect examples.  The issue in Retractable is an old one: should the Federal Circuit give deference to district judges on claim construction?  Judge Moore (joined by CJ Rader) and Judge O’Malley both argued the court should.  Their dissents each begin with the assertion that the Supreme Court in Markman held that claim construction is a “mongrel practice” with both legal and factual components, and this counsels for deference to trial judges.

Let me start by debunking this legalistic argument.  The Supreme Court in Markman did not hold that claim construction is a “mongrel practice.”  It started off by observing that claim construction is intrinsically a mongrel practice, and then held that the Court would adopt a legal fiction that claim construction was a pure question of law.

Why do I say this?  If it is correct that Markman held that claim construction has a factual component, then the result under traditional common law principles is not that trial judges get to decide the factual component.  Trial judges do not decide facts; juries do.  Some well-known exceptions are for suits in equity, for jurisdictional facts, and for procedural facts.  But nobody contends that these exceptions apply.  The claim-construction-is-factual line of reasoning is a legalistic and logical dead end.

Rather, the case for deference to district judges on claim construction must succeed, if at all, entirely based on policy-based concerns.  Trial judges have better access to evidence than appellate judges, and yet they are more experienced at dealing with legal documents like patents than juries.  This is a perfectly plausible policy-based argument, and is almost certainly the true reason for Judges Moore and O’Malley to seek deference for trial judges.  Too bad they feel the need to couch the argument in formalist terms.

Construing Claim Constructions

By Jason Rantanen

Cordis Corporation v. Boston Scientific Corporation (Fed. Cir. 2011) Download 10-1311 -1316-1
Panel: Bryson, Mayer, and Gajarsa (author)

Cordis v. BSC
turns on an interpretation of a construction of the claim term "undulating."  In this case, Cordis obtained a jury verdict of infringement of Patent No. 5,879,370 against Boston Scientific Corporation.  Prior to trial, the district court construed the term "undulating" to mean "rising and falling in waves, thus having at least a crest and a trough."  Slip Op. at 11.  After Cordis obtained its favorable verdict, BSC renewed its motion for judgment as a matter of law on noninfringement, arguing that "Cordis inappropriately altered the parties' and the court's understanding of the term 'undulating'," and that under the "intended" construction the evidence presented at trial could not support a conclusion that this claim element was met by the accused product.    Slip Op. at 11.  The district court granted BSC's motion and Cordis appealed.

Construing Constructions: On appeal, the CAFC confirmed the propriety of BSC's argument.  "The question here is whether BSC did, in fact, seek to alter the district court’s claim construction," a construction Cordis did not challenge.  Slip Op. at 12.  It did not.  "No rule of law restricted BSC from seeking to clarify or defend the original scope of its claim construction."  Slip Op. at 12.  However, "because BSC did not object to the court’s jury instruction regarding the construction of the term “undulating,” “[t]he verdict must be tested by the charge actually given [under] the ordinary meaning of the language of the jury instruction,” Hewlett-Packard, 340 F.3d at 1321."  Id.

In deciphering the "ordinary meaning" of the district court's construction, the CAFC first turned to a general purpose dictionary definition of 'waves' to conclude that 'crest' and 'trough,' "as used in the district court's claim construction, implicate changes of direction, with the curve extending beyond the point of inflection."  Slip Op. at 13.  Although Cordis cited expert testimony and dictionary entries of its own, the CAFC was not persuaded.  The CAFC also looked to the prosecution history, which further suggested a construction of "undulating" that meant more than just a single curve. 

Applying this interpretation of the district court's claim construction, the CAFC concluded that Cordis had indeed failed to offer substantial evidence of infringement.

Inequitable conduct: This case was involved in a prior appeal, Cordis Corp. v. Boston Scientific Corp., 188 F. App’x. 984, 985 (Fed. Cir. 2006), in which the CAFC addressed a district court finding of inequitable conduct.  In that appeal, the CAFC affirmed the materiality of the conduct at issue but remanded to the district court for further findings of fact relating to intent.  On remand, the district court reached an alternate conclusion, deciding that, on reflection, the evidence of record failed to support a finding of deceptive intent under a clear and convincing standard.  On appeal, the CAFC affirmed the finding of no inequitable conduct, noting in particular the deference given to district courts on issues of credibility.


Interpretations of constructions raise a difficult issue for the Federal Circuit, and have implications for litigation predictability.  While the panel in this case did not directly identify the standard of review it applied to the district court's interpretation of the construction, the analytic structure of the opinion follows the same approach that the CAFC has traditionally employed when construing claims generally: look at the evidence and arrive at its own conclusion, i.e. de novo.  In this instance, the methodology used by the panel seems to harken back to the Texas Digital line of claim construction: start by determining the ordinary meaning of a word using tools such as dictionaries, then look to the intrinsic evidence to see if it compels a different result.  Perhaps this approach may be more defensible in light of the subject being interpreted, but it seems at odds with the principles announced in Phillips.

The interpretation issue in this case also raises a possible red flag against the concept of routine interlocutory review of claim constructions, a proposal frequently offered as reducing litigation costs and enhancing the predictability of litigation.  If a claim construction itself is subject to a subsequent interpretation, are efficiencies truly added by having the CAFC offer an early construction?  There is a real possibility that, if such a proposal were implemented, the result would be a rise in appeals involving not just claim constructions, but interpretations of claim constructions.

iLOR v. Google: Rejected Claim Construction Does Not Render Case “Objectively Baseless”

By Jason Rantanen

iLOR, LLC v. Google, Inc. (Fed. Cir. 2011)
Panel: Rader, Linn, Dyk (author)

This case involved a district court exceptional case determination based a finding that the suit was objectively baseless and brought in bad faith.  iLOR, the assignee of Patent No. 7,206,839, sued Google for infringement of the '839 patent by Google's Notebook product.  In denying iLOR's request for a preliminary injunction, the district court rejected iLOR's proposed construction of the only claim term in dispute, subsequently granting summary judgment of noninfringement.  The Federal Circuit affirmed the district court's denial of the preliminary injunction, agreeing that the language of the claim, the specification and the prosecution history supported the district court's construction.  See iLOR, LLC v. Google, Inc., 550 F.3d 1067 (Fed. Cir. 2008).  Following the Federal Circuit's disposition of that appeal, the district court granted Google's request to recover its attorneys' fees and costs and expenses, finding the case exceptional on the ground that it was "not close" on the merits (i.e.: ("objectively baseless") and iLOR had acted in subjective bad faith.  iLOR appealed.

In reversing the district court, the CAFC first likened the exceptional case standard for a suit brought by a patent plaintiff (absent misconduct during patent prosecution or litigation) to that of willful infringement.  "The objective baselessness standard for enhanced damages and attorneys’ fees against a non-prevailing plaintiff under Brooks Furniture is identical to the objective recklessness standard for enhanced damages and attorneys’ fees against an accused infringer for § 284 willful infringement actions under In re Seagate Technology, LLC, 497 F.3d 1360 (Fed. Cir. 2007) (en banc)."  Slip Op. at 8-9.  Thus, just as willfulness requires an assessment of both objective and "subjective" (i.e.: known or so obvious that it should have been known) prongs, so too does the exceptional case determination. And just as for willfulness, the objective assessment "is to be determined based on the record ultimately made in the infringement proceedings."  Id. at 10.

Comment: At some points, the Federal Circuit's opinion is confusingly imprecise in its usage of "objective baselessness."  Although in some instances it refers to the "objective baselessness" standard as being identical to the overall objective recklessness standard for willfulness (which includes, according to the court, both objective and subjective elements), at other times it treats it as being identical to only the "objective" prong of the analysis.  The only reading that makes sense is that when the court indicates that "objective baselessness" is identical to the willfulness "objective recklessness" standard, what it is really referring to is the overall standard for an exceptional case determination based on a meritless case theory, while when it compares it to the "objective" prong of the willfulness analysis, it really is referring to "objective baselessness."

Applying this framework, the CAFC concluded that iLOR's claim construction was not objectively baseless, and thus it was unnecessary to consider the issue of subjective bad faith.  The CAFC pointed to iLOR's arguments supporting its proposed construction, which – although the court disagreed with them – had some merit.  The CAFC also commented on the difficulty of claim construction, "in which the issues are often complex and the resolutions not always predictable."  Id. at 13.  And the court noted that the fact that it "held oral argument and issued a precedential written opinion in the first appeal suggests that we did not regard the case as frivolous."  Id. at 13-14.  In short, "simply being wrong about claim construction should not subject a party to sanctions where the construction is not objectively baseless."  Id. at 14.

Akamai v. Limelight: Joint Infringement Requires an Agency Relationship or a Contractual Obligation

By Jason Rantanen and Dennis Crouch

Akamai Technologies, Inc. v. Limelight Networks, Inc. (Fed. Cir. 2010)
Panel: Rader, Linn (author), Prost

Three years ago, in BMC Resources, Inc. v. Paymentech, L.P., 498 F.3d 1373 (Fed. Cir. 2007), the Federal Circuit sharply limited the ability of patent holders to assert claims of joint infringement.  The BMC decision was further bolstered by Muniauction, Inc. v. Thomson Corp. and I-Deal (Fed. Cir. 2008). Akamai v. Limelight expands on the "control or direct" rule announced in BMC and Muniauction, explaining that joint infringement requires an agency relationship or a contractual obligation to carry out the relevant steps. 

Akamai's Claim of Joint Infringement
In order to win a patent infringement case, a patentee must prove that a single entity practiced every element (either literally or by equivalents) of at least one valid, enforceable claim. Joint infringement issues can arise when a patent holder asserts method claims over activities whose steps are not carried out by a single party.  For example, if a patent claims a method involving performing steps A, B, and C, the patent holder may need to argue joint infringement (as opposed to straightforward direct infringement) if steps A and B are performed by one party and step C is performed by a second party. 

In Akamai, while the accused party (Limelight) performed the majority of the steps of the asserted claims, at least one of the steps of each claim was performed by its customers.  The patent, No. 6,108,703, is directed to an improved method for storing web page content.  Conventionally, the entirety of a web page, including both the page itself and embedded content (such as graphics) is stored on a single server, or mirrored in its entirety across multiple servers.  The patents-in-suit claim a new approach, which involves storing only the embedded objects on mirrored servers (called a "Content Delivery Network," or "CDN"), while having the webpage itself continue to reside on the content provider's servers.  In order to make this system work, the claims further require that the object URLs be "tagged" to resolve to the CDN. 

Daniel Lewin and his adviser Thomas Leighton devised these methods (or algorithms) while at MIT where Leighton was the head of MIT's Computer Science and Artificial Intelligence Laboratory.  The pair founded Akamai, and their invention continues to serve as a basis for the company's core business.  Lewin was killed aboard American Airlines flight 11 when it crashed into the north tower of the World Trade Center on September 11, 2001.

Limelight, Akamai's direct competitor in the CDN business, performed most of the claimed steps but had its customers (companies such as Netflix) tag the URLs.  Because some of the steps were performed by Limelight and some by its customers, Akamai relied on a theory of joint liability, arguing that Limelight controls or directs the activities of its customers.  At trial, the jury sided with Akamai and awarded over $40 million in lost-profit-damages. The district court rejected the jury verdict and supplemented its own non-infringement judgment – holding that there was "no material difference between Limelight's interaction with his customers and that of Thomson in Muniauction."

On appeal, Akamai contended that substantial evidence supported the infringement finding, arguing that Limelight "(1) creates and assigns a unique hostname for the content provider; (2) provides explicit step-by-step instructions to perform the tagging and serving claim steps; (3) offers technical assistance to help content providers with their performance of the claim step; and (4) contractually requires content providers to perform the tagging and serving claim steps if they utilize the Limelight service."  Slip Op at 11. 

Important holdings
In affirming the district court's judgment of noninfringement, the CAFC expanded on its ruling in BMC that "joint liability may be found when one party 'control[s] or direct[s]' the activities of another party."  Slip Op. at 9.  After noting the foundational nature of this standard, the Akamai panel further held that "what is essential is not merely the exercise of control or the providing of instructions, but whether the relationship between the parties is such that acts of one may be attributed to the other."   Id. at 12.  The court interpreted this as requiring either an agency relationship or a contractual obligation: "as a matter of Federal Circuit law that there can only be joint infringement when there is an agency relationship between the parties who perform the method steps or when one party is contractually obligated to the other to perform the steps."  Slip Op. at 14.

Analyzing the issue as a question of agency law, the CAFC concluded that no substantial evidence supported a finding that Limelight's customers perform any of the steps of the claimed method as agents for Limelight.  (Citing the Restatement (3rd) of Agency §1.01). The court also rejected Akamai's theory that Limelight's customers are contractually required to perform the tagging step.  Rather, the court stated, the contract does not obligate the customers to perform any of the method steps; instead, it "merely explains that the customer will have to perform the steps if it decides to take advantage of Limelight's service."  Slip Op. at 16.

Note: The court repeated the warning it set forth in BMC Resources, 498 F.3d at 1381, that concerns about the difficulty of proving infringement of claims that must be infringed by multiple parties "by proper claim drafting.  A patentee can usually structure a claim to capture infringement by a single party."  Slip. Op. at 17 (quoting BMC Resources).  Failing this, the court suggested (citing Mark Lemley's Divided Infringement article) that patentees may be able to correct a claim by seeking a reissue patent.

Claim Construction
Akamai also challenged the district court's construction of two claim terms in related patents, contending that both constructions imported limitations from the specification into the claims.  In a fact-intensive analysis, the CAFC rejected Akamai's arguments, concluding that the district court correctly interpreted the disputed terms given the treatment of the invention in the specification and the lack of any contrary evidence in the prosecution history. 

Preambles as Limitations

By Jason Rantanen

American Medical Systems, Inc. v. Biolitec, Inc. (Fed. Cir. 2010)
Panel: Bryson (author), Dyk (dissenting), and Prost

It may come as no surprise that the law on whether claim preambles can serve as limitations is unclear.  The Federal Circuit is aware of this issue, and at least one judge suggests that it may be time for the court to address this issue en banc.

The patent in this case, No. 6,986,764, relates to technology for vaporizing tissue using laser radiation.  The invention can be used to treat Benign Prostatic Hyperplasia, a condition in which growth of the prostate gland restricts the passage of urine out of the bladder and through the urethra.  By vaporizing or ablating some tissue, the size of the prostate is reduced, thus reducing bladder outlet obstructions.  Although laser radiation was known in the art, various problems were associated with its use.

The inventors of the '764 patent determined that by using high "volumetric power density" (a high amount of energy delivered to a given volume of tissue) they could produce increased vaporization efficiency while minimizing one of the problems associated with the procedure, residual coagulation.  The patent is directed to various methods and devices for achieving this high volumetric power density by manipulating variables such as wavelength, output power, beam quality, irrigant composition, and distance between the optical fiber and the tissue.

The dispute on appeal hinged on whether the preamble constituted a limitation.  Claim 31 is representative of the method claims. (The apparatus claims are similar, but recite "[a]n apparatus for photoselective vaporization of tissue.")  It recites:

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 mm2.

During claim construction, the district court determined that the preamble phrase "photoselective vaporization" was a "fundamental characteristic" of the invention, and construed the term 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."  Based on this construction, the court granted summary judgment in favor of the accused infringer.

On appeal, the majority disagreed, concluding that the preamble phrase "photoselective vaporization of tissue" does not limit the claims of the '764 patent.  The court first noted the limited circumstances in which the preamble may limit claim scope:

“Generally,” we have said, “the preamble does not limit the claims.”  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.” 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.”  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.”  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.”

Slip Op. at 8-9 (internal citations omitted).  After rejecting a prosecution history-based argument and the argument that the preamble phrase provided a necessary antecedent basis, the court determined that the phrase "does not embody an essential component of the invention":

Instead, the term “photoselective vaporization” is simply a descriptive name for the invention that is fully set forth in the bodies of the claims….The bodies of the asserted apparatus claims (claims 63-64) describe a structurally complete device, including a laser adapted to deliver “radiation at a wavelength and irradiance . . . sufficient to cause [tissue] vaporization[.]” The bodies of those claims identify the covered wavelengths by function (“sufficient to cause vaporization”), and nothing in the claim language suggests that the term “photoselective” further limits those wavelengths.

Slip Op. at 10 (internal citations omitted).

Judge Dyk disagreed.  After first noting the confusing and unclear nature of the court's jurisprudence on this issue, he suggested that the court should dispense with the current articulation and instead apply the rule that preambles always limit claims:

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 bind-ing, 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 infringe-ment 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 inven-tion’s scope. By creating a uniform rule that all pream-bles are limiting, we would ensure the patentee has the burden of drafting a patent that avoids confusion as to the scope of the claims….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.

Dissent at 3-4.  He then turned to the issue of whether the preamble phrase in this case limited the scope of the patent, and concluded that it did based on the prosecution history and what he viewed as a definition of the term in the Summary of the Invention.  He also disagreed with the majority that the district court's construction would be inconsistent with the specification. 

Construing the “Function” of a Means-Plus-Function Claim Element

Gregory Baran v. Medical Device Technologies (Fed. Cir. 2010)

Dr. Baran sued MDTech for infringing his patents covering automated biopsy instruments. Soon-to-be Federal Circuit Judge Kathleen O’Malley over-saw the district court case. After construing several disputed claims, Judge O’Malley ordered summary judgment of non-infringement. On appeal, the Federal Circuit affirmed.

Means-Plus-Function: I’ll focus on an interesting question raised regarding Baran’s means-plus-function (MPF) limitation. The limitation reads as follows: a “release means for retaining the guide in the charged position.” 

35 USC 112 p6 provides for MPF claim elements expressed “as a means or step for performing a specified function.”  The statute calls for the limitation to be “construed to cover the corresponding structure, material, or acts described in the specification and equivalents thereof.”  Federal Circuit precedent has logically added that the statutory “corresponding structure” are structures that perform the claimed function.

What is the Claimed Function?: Here, the Federal Circuit was asked to construe Baran’s MPF element to identify the claimed function.  MDTech argued that the claimed “release means for retaining” required a structure that exhibited both a releasing function and a retaining function.  Dr. Baran argued that the claimed function was only that of retaining.  On appeal, the Federal Circuit agreed with the lower court that the means-preamble “release” added a functional limitation to the claim element.

[T]he claim language recites both a release function and a retention function. Dr. Baran’s argument regarding the placement of the term “release” is unavailing. The relevant inquiry is whether the term at issue is purely functional. See Signtech USA, Ltd. v. Vutek, Inc., 174 F.3d 1352, 1356 (Fed. Cir. 1999) (construing “ink delivery means” to be equivalent to “means for ink delivery” because “ink delivery” was purely functional language); Al-Site Corp. v. VSI Int’l, Inc., 174 F.3d 1308, 1318 (Fed. Cir. 1999) (“[W]hen it is apparent that the element invokes purely functional terms . . . the claim element may be a means-plus-function element despite the lack of express means-plus-function language.”). In the context of the ’797 patent, the term “release” is not an idle description but a vital function to be performed by the means-plus-function element. The patent does not recite a biopsy instrument that retains indefinitely without release; rather, the contemplated function is to retain for the express purpose of producing a spring-loaded release on demand. The claim language ties both functions to the same means-plus-function element, so it is appropriate that the element be construed accordingly.

Although it is difficult to take-away lessons from claim construction decisions, a potential best-practices approach to drafting MPF claims may be to eliminate any adjectives tied directly to the “means.”  Of course, my best practice suggestion is intended for those times when you want to draft MPF claims with clarity.

Adams Respiratory Therapeutics v. Perrigo – construction of pharmacokinetic claim terms

Adams Respiratory Therapeutics, Inc. v. Perrigo Company (Fed. Cir., August 5, 2010)
Panel: Linn, Moore (author), Friedman

By Jason Rantanen

Adams holds patent number 5,372,252, which covers an extended release formulation containing guaifenesin (an expectorant used to thin, loosen, and help expel mucus that causes congestion).  Perigo sought FDA approval for a generic version of Adams' product, Mucinex®.  After construing the claims, the district court granted summary judgment of noninfringement.  Adams appealed that decision.

The claim terms in dispute related to pharmacokinetic parameters.  These parameters are used to characterize the rate and extent of absorption of the active pharmaceutical ingredient ("API").  The primary term at issue, Cmax, indicates the maximum concentration of the API following dosing.

"Equivalent Cmax"
The parties' main dispute was over the meaning of the term "equivalent" in the context of "provides a Cmax in a human subject equivalent to the Cmax obtained when the first of three doses of a standard immediate release formulation having one third the amount of guaifenesin is dosed."  For purposes of FDA approval, a formulation is considered to be bioequivalent if, among other things, its Cmax is within 80% to 125% of the value with which it is being compared at a 90% confidence interval. The district court agreed with Perrigo that "equivalent" should be construed to mean equivalent under the FDA bioequivalence guidelines.

On appeal, Adams challenged the requirement of a 90% confidence interval, arguing that it makes sense when seeking FDA approval, but not when proving infringement. 

The Federal Circuit agreed with Adams.  In doing so, it rejected Perrigo's argument that the inventors had expressly defined "equivalent" as te FDA's bioequivalence guidelines.  Rather, the court construed Adams' reference to the FDA guidelines as referring specifically to the 80-125% range, not to the requirement of a 90% confidence interval.  According to the court:

Requiring a 90% confidence interval would inappropriately raise the bar for establishing infringement.  Adams must show that it is more likely than not that Perrigo's ANDA product will have a Cmax within the 980-125% range. Adams is not required to show that Perrigo's product will meet this requirement 9 times out of 10.

Slip Op. at 8.

Comment: This interpretation opens up a box of statistical worms, and I suspect that down the line the court may regret its venture into probability theory.  For the time being, however, it gives parties useful language to quote when attempting to prove infringement (and perhaps invalidity) via clinical results. 

A ≈ B ≈ C therefore A ≈ C
Adams also appealed the district court's ruling that it  impermissibly compared the accused product to Mucinex.  Adams' argument was that because the accused product was bioequivalent to Mucinex, and Mucinex was bioequivalent to a standard immediate release ("IR") product, then the accused product had a Cmax equivalent to the IR product. 

The Federal Circuit agreed that, under the circumstances of this case, Adams' argument was sufficient to preclude summary judgment of noninfringement.  The court cautioned, however, that "[i]f Adams had relied on the mere fact of bioequivalence of the two sets of products (and no PK data or Cmax values, that would not be enough to survive summary judgment."  Slip Op. at 11.  Here, however, Adams presented actual PK data and Cmax values, which a fact-finder could look at when assessing equivalence between the accused product and an IR product. 

The court also addressed the meaning of the term "bioavailable" in the context of the '252 patent.  The dispute hinged on whether the phrase "fully bioavailable in the subject's stomach" meant "both release and availability in the stomach for absorption, wherever that absorption might occur." 

Perrigo argued that because "bioavailable" is commonly understood to mean absorption, thus requiring the guaifenesin to be absorbed in the stomach.  Because guaifenesin is primarily absorbed in the small intestine, this construction would preclude a finding of infringement.

The court rejected the proposed construction as inconsistent with the specification: "Although the specification never expressly defines bioavailable, it uses the term when describing the availability of the drug for absorption, not the actual absorption."  Slip Op. at 14.  The court further noted that Perrigo's construction would exclude the preferred embodiment, which "is rarely, if ever, correct and would require highly persuasive evidentiary support."

Doctrine of Equivalents
Finally, Adams argued that the district court erroneously precluded it from relying on the doctrine of equivalents with respect to a dependant claim requiring that the total amount of guaifenesin released in to the patient be at least 3500 hr*ng/mL.  The panel concluded that the use of a numerical limit did not preclude Adams from arguing that an amount of 3494.38 hr*ng/mL was equivalent to 3500 hr*ng/mL. 

Ring Plus v. Cingular Wireless

By Jason Rantanen

Although the court ultimately reversed the determination of inequitable conduct based on a lack of intent, its discussion of materiality is significant because the misrepresentation at issue occurred in the patent itself, in the form of statements about a prior art reference.  Prosecutors may want to take special note of this opinion in crafting their Background of the Invention sections. 

Ring Plus, Inc. v. Cingular Wireless Corp. (Fed. Cir., August 6, 2010)
Panel: Lourie, Gajarsa and Moore (author)

Ring Plus is the assignee of Patent No. 7,006,608 (the '608 patent), which relates to a software based algorithm and method for generating and delivering messages over a phone line that replace or overlay a ring-back signal.

After granting summary judgment of noninfringement, the district court held a bench trial on the unenforceability of the '608 patent.  Following the bench trial, the district court concluded that the '608 patent was unenforceable due to inequitable conduct.  Ring Plus appealed both determinations, along with the denial of its motion to disqualify Cingular's counsel. 

Inequitable conduct: Materiality but no Intent
The district court's inequitable conduct determination was based on two alleged misrepresentations concerning the substance of two prior art references, Strietzel and Sleevi.  The district court found that the first misrepresentation was in the Background of the Invention section of the '608 patent, which asserted that both references proposed hardware based systems but no software to operate those systems.  Contrary to this assertion, the district court found, one of skill in the art would have understood the references to disclose software-based algorithms.1 

The panel agreed that this was a material misrepresentation.  Although neither reference explicitly disclosed software, the panel could not say that the district court clearly erred in finding that a person of ordinary skill in the art would have understood the references to disclose software-based algorithms. 

In arriving at the conclusion that the statement about the contents of the prior art constituted a misrepresentation, the panel rejected the contention that it was merely attorney argument.  The court did not address this issue in any depth, merely stating that because the statement was a misrepresentation, it "was outside the boundas of permissible attorney argument."  Slip Op. at 9.

Comment: I am a troubled by the court's cursory statement on this point because of the ambiguity it creates.  These types of sweeping assertions, made without addressing the substance of the argument or citing relevant authorities, are the kinds of things that are likely to tie attorneys and judges in knots.  Indeed, the court's quotation from Rothman is particularly perplexing, as Rothman reached the opposite conclusion on similar facts.  At a minimum, one would expect the court to explain why Rothman does not apply.

Ultimately, however, the panel concluded that Cingular had failed to present clear and convincing evidence of intent to deceive.  In arriving at this conclusion the court noted that the references were ambiguous as to operating software, and the prosecuting attorney's testimony gave rise to the inference that the applicants believed that the two references did not disclose software for operating a telephone system.  Because this inference was as reasonable as the district court's inference of deceptive intent, the district erred in its finding of deceptive intent.

Other holdings
The panel also addressed Ring Plus's challenge to the district court's construction of two claim terms, which formed the basis of the noninfringement ruling.  The court affirmed the district court's construction, relating to the sequence of steps in the '608 patent.  In addition, the court rejected Ring Plus's argument that Cingular's counsel should have been disqualified for ex parte contact with a Ring Plus director and officer.  The court concluded that there was no evidence of impropriety under Fifth Circuit law.

1The district court also found that the applicants made a misrepresentation about these references during prosecution; the panel concluded that this statement was not a misrepresentation.

Genus-Species; Doctrine of Equivalents; and Patentable Subject Matter

By Dennis Crouch

For many, the most interesting aspect of this case comes at the end in Judge Dyk’s dissent. Dyk makes the case that genes should not be patentable. 

* * * *

Intervet Inc. v. Merial Limited (Fed. Cir. 2010)

In 2006, Intervet filed a complaint against Merial — asking the DC District Court for a declaratory judgment that Intervet’s Porcine Circovirus vaccine (PCV-2) did not infringe Merial’s gene patent.  Merial’s patent claims both the isolated DNA molecule of PCV-2 and a vector that contains the DNA.  The application includes a listing of several different sequences that all fall within the PCV-2 category. 

Although Intervet also uses a PCV-2 vector. The DJ plaintiff argues that its DNA molecule is different from the one described and deposited by Merial. The district court agreed — holding that the Intervet product was only 99.7% homologous to the closest deposited sequence and therefore outside of the literal claim scope. The district court also applied prosecution history estoppel to rejected Merial’s claims of infringement under the doctrine of equivalents (DOE). On appeal, the Federal Circuit reversed on both claim construction and DOE.

Genus Not Limited to Examples: The asserted claim includes a limitation of a “PCV-2” DNA molecule. The District Court limited that term to cover only the DNA sequences that were deposited with the PTO. On appeal, the Federal Circuit rejected that construction as overly limiting. Rather, the appellate panel held that the deposited sequences serve as a representative sample of PCV-2 DNA sequences. “Sequences are representative of the scope of broader genus claims if they indicate that the patentee has invented species sufficient to constitute the genera. Here, the deposited strains are representative species of the larger ‘type II’ genus, where the genus is identified and claimed as the invention.” In describing its invention, the specification noted that the PCV-2 desposited sequences had a 96% homology and that the invention did not cover PCV-1 sequences that at most shared 76% homology with the deposited sequences.  Taking those quantitative limits from the specification, the Federal Circuit ruled that the claimed PCV-2 molecule should be construed as being “about 96% or more homologous with the … sequences disclosed in the present specification, and about 76% or less homologous with the [disclosed PCV-1] sequence.”

What is Equivalents are Surrendered by a Narrowing Amendment: An accused infringer may still be liable even though its product does not literally infringe every element of an asserted patent claim.  Under the doctrine of equivalents (DOE), a patentee may be able to provie infringement by showing that one or more elements of the accused product are equivalent to elements in the claim.  Under the limiting doctrine of prosecution history estoppel (PHE), a patentee will ordinarly be estopped from claiming DOE over a claim element that was narrowed during prosecution. (A narrowing amendment made for purposes related to patentability creates a rebuttable presumption that estoppel applies.)

Here, one of Merial’s original claims was directed to a markush group of open reading frames (ORFs) that had been described in the specification as “ORFs 1–13.”  In an initial rejection, the examiner suggested that the limitation could refer to ORFs of non-PCV-2 molecules. Although the patentee argued that the claim was clear, it still added the limitation that the claimed ORFs were PCV-2 ORFs.  The Federal Circuit held that this was a narrowing amendment substantially related to patentability. That narrowing amendment therefore created a presumption that the patentee had surrendered all equivalents that relate to non-PCV-2 ORFs. The district court erred, however, in holding that this narrowing amendment would estopp the the patentee from asserting that the claims cover a non-claimed PCV-2 ORF as an equivalent. “Such a draconian preclusion would be beyond a fair interpretation of what was surrendered. The rationale for the amendment was to narrow the claimed universe of ORFs down to those of PCV-2, and bore only a tangential relation to the question of which DNA sequences are and are not properly characterized as PCV-2.”

Dissenting-in-part, Judge Dyk discussed his argument that the claims directed toward the isolated form of a naturally occurring gene are likely unpatentable under 35 U.S.C. § 101.

[T]he isolated DNA claim raises “substantial issues of patentable subject matter under 35 U.S.C. § 101. . . . Neither the Supreme Court nor this court has directly decided the issue of the patentability of isolated DNA molecules. Although we have upheld the validity of several gene patents, none of our cases directly addresses the question of whether such patents encompass patentable subject matter under 35 U.S.C. § 101. . . .

I think that such patents do in fact raise serious questions of patentable subject matter. The Supreme Court’s recent decision in Bilski v. Kappos has reaffirmed that “laws of nature, physical phenomena, and abstract ideas” are not patentable. No. 08-964, slip op. at 5 (U.S. June 28, 2010) (quoting Diamond v. Chakrabarty, 447 U.S. 303, 309 (1980)); Funk Bros. Seed Co. v. Kalo Inoculant Co., 333 U.S. 127, 130 (1948). Just as the patentability of abstract ideas would preempt others from using ideas that are in the public domain, see Bilski, slip op. at 13, so too would allowing the patenting of naturally occurring substances preempt the use by others of substances that should be freely available to the public. Thus, “a new mineral discovered in the earth or a new plant found in the wild is not patentable subject matter. Likewise, Einstein could not patent his celebrated law that E=mc2; nor could Newton have patented the law of gravity.” Chakrabarty, 447 U.S. at 309. These aspects are properly conceptualized as representing a public domain, “free toall men and reserved exclusively to none.” Id. (quoting Funk Bros., 333 U.S. at 130) (quotation mark omitted).

In Funk Brothers, the Court considered the patentability of a mixture of several naturally-occurring species of bacteria. 333 U.S. at 128-31. The patented product was a mixture of bacteria used in agricultural processes, enabling plants to draw nitrogen from the air and convert it for usage. The inventor discovered that certain strains of the bacteria were effective in combination with one another, and contrary to existing assump-tions, did not exert mutually inhibitive effects on each other. The Court held that the invention was not pat-entable subject matter. Id. at 131. The inventor “did not create a state of inhibition or of non-inhibition in the bacteria. Their qualities are the work of nature. Those qualities are of course not patentable.” Id. at 130. The Court furthermore noted:

The qualities of these bacteria, like the heat of the sun, electricity, or the qualities of metals, are part of the storehouse of knowledge of all men. They are manifestations of laws of nature, free to all men and reserved exclusively to none. He who discovers a hitherto unknown phenomenon of na-ture has no claim to a monopoly of it which the law recognizes. If there is to be invention from such a discovery, it must come from the applica-tion of the law of nature to a new and useful end.


In Chakrabarty, the Court considered whether a human-made microorganism is patentable subject matter under section 101. 447 U.S. at 305. The microorganism in question was a bacterium that had been genetically engineered to break down crude oil. In concluding that the man-made bacteria was patentable, the Court observed that the claim “is not to a hitherto unknown natural phenomenon, but to a nonnaturally occurring manufacture or composition of matter.” Id. at 309. The Court went on to distinguish Funk Brothers on the ground that the Chakrabarty bacterium possessed “markedly different characteristics from any found in nature. . . . His discovery is not nature’s handiwork, but his own; accordingly it is patentable subject matter under § 101.” Id. at 310 (em-phasis added).

Thus, it appears that in order for a product of nature to satisfy section 101, it must be qualitatively different from the product occurring in nature, with “markedly different characteristics from any found in nature.” It is far from clear that an “isolated” DNA sequence is qualita-tively different from the product occurring in nature such that it would pass the test laid out in Funk Brothers and Chakrabarty. The mere fact that such a DNA molecule does not occur in isolated form in nature does not, by itself, answer the question. It would be difficult to argue, for instance, that one could patent the leaves of a plant merely because the leaves do not occur in nature in their isolated form.



Sun Pharmaceuticals v. Eli Lilly: obviousness-type double patenting in the pharmaceutical context

Sun Pharmaceutical Industries, Ltd. v. Eli Lilly and Company (Fed. Cir. July 28, 2010)

By Jason Rantanen

Double-patenting issues arise when two commonly owned applications cover the same or similar inventions.  The issues in this appeal revolved around an earlier patent claiming a composition of matter and describing a method for using that composition, and a later patent claiming that method of use. 

Both of the patents in this case, Patent No. 4,808,614 (the '614 patent) and Patent No. 5,464,826 (the '826 patent) relate to gemcitabine, the active ingredient of Lilly's Gemzar® product.  The '614 patent claims both gemcitabine itself, as well as a method of using it to treat viral infections.  In addition, the '614 patent's specification discloses using gemcitabine to treat cancer.  The '826 patent claims a method of treating cancer comprising administering a therapeutically effective amount of gemcitabine.  The difference was important: the '614 patent expired on May 15, 2010, while the '826 patent does not expire until November 7, 2012.

Note: The applications leading to both the '614 and '826 patents were filed on the same day, December 4, 1984.  The '614 was a continuation-in-part of application No. 473,883 ("the '883 application"), which did not disclose using gemcitabine to treat cancer.  That information was added as part of the continuation-in-part. 

After filing an Abbreviated New Drug Application ("ANDA") for a generic version of Gemzar®, Sun Pharmaceuticals, sought a declaratory ruling that the '826 patent was invalid and not infringed.  Lilly counterclaimed for infringement of the '826 and '614 patents.  The '614 patent was not at issue in this appeal.

Obviousness-type double patenting applies
Applicants are barred from obtaining multiple patents covering the same invention by the doctrine of double patenting.  There are two types of double patenting: statutory double patenting, which prohibits a later patent from covering the identical invention, and obviousness-type double patenting, which prevents a later patent from covering a slight variation of an earlier patented invention.

On appeal, the panel agreed with the district court and Sun that the latter type of double patenting occurred here, thus invalidating the asserted claims of the '826.  The basis for the court's decision were two prior opinions, Geneva v. GlaxoSmithKline, 349 F.3d 1373, and Pfizer v. Teva, 518 F.3d 1353.  In Geneva, the earlier patent claimed a compound and the specification disclosed its effectiveness for inhibiting beta-lactamase.  The later patent claimed a method of using the compound to affect beta-lactamase inhibition.  Similarly, in Pfizer, the earlier patent claimed several compounds and the specification disclosed their use in treating inflamation; the later patent claimed a method of using these compounds for treating inflammation.  In both cases, the court ruled that the claims were not "patentably distinct," and thus the latter claims were invalid for obviousness-type double patenting.  

While Lilly argued that Geneva and Pfizer did not apply because "the specification of the earlier patent disclosed a single use for the claimed compound, which was an essential part of the patented invention and thus necessary to patentability," Slip Op. at 8, the court rejected that argument for two reasons.  First, the court disagreed that the specification in Pfizer disclosed more than one utility for the claimed compound.  In addition, the court read the rule of Pfizer as simply that "obviousness-type double patenting encompasses any use for a compound that is disclosed in the specification of an earlier patent claiming the compound and is later claimed as a method of using that compound.  Pfizer never implies that its reasoning depends in any way on the number of uses disclosed in the specification of the earlier patent."  Slip Op. at 10. 

The court also rejected Lilly's argument that the specification of an earlier application should have been consulted, as opposed to the specification of the '614 patent.  Drawing upon its claim construction precedent, the court noted that the specification is relevant to determining the coverage of the claims, which is at the heart of the obviousness-type double patenting analysis.  The court further noted that "consulting the specification of the issued patent, as opposed to an earlier version, is consistent with the policy behind double patenting," which rests "on the fact that a patent has been issued and later issuances of a second patent will continue protection, beyond the date of expiration of the first patent of the same invention or an obvious variation thereof."  Slip Op. at 14-15.

Becton, Dickinson and Co. v. Tyco Healthcare Group (Fed. Cir. 2010)

Tyco appealed a jury verdict that its safety needles infringed BD’s US Patent No. 5,348,544.  The claims require a “spring means” that is “connected to said hinged arm” and is designed “for urging said guard along said needle cannula.” 

On appeal, the Federal Circuit reversed the infringement decision based on claim construction — holding that as a matter of English-language-logic, the claims require a spring and hinged arm that are structurally distinct.

The unequivocal language of the asserted claims . . . requires a spring means that is separate from the hinged arm. . . . Where a claim lists elements separately, “the clear implication of the claim language” is that those elements are “distinct component[s]” of the patented invention. (Quoting Gaus v. Conair Corp., 363 F.3d 1284, 1288 (Fed. Cir. 2004)). . .  There is nothing in the asserted claims to suggest that the hinged arm and the spring means can be the same structure.

If the hinged arm and the spring means are one and the same, then the hinged arm must be “connected to” itself and must “extend between” itself and a mounting means, a physical impossibility. A claim construction that renders asserted claims facially nonsensical “cannot be correct.”

Because the hinged arm of the Tyco needles performed the spring function themselves (as opposed to having a separate spring), the court ruled that those needles could not infringe.

In dissent, Judge Gajarsa provides a de-construction of the majority opinion — writing that:

The majority avoids the critical issue upon which this decision turns; i.e., whether 35 U.S.C. § 112, ¶ 6 governs the claim construction of the “spring means” limitation. In a brief footnote, the majority sweeps and brushes aside the means-plus-function analysis as unnecessary in light of the “plain language of the claims.” Without having analyzed the scope of the claims, the majority somehow concludes that the claim language covers only devices having separate “spring means” and “hinged arm” structures. Then applying this simplistic claim construction to analyze the sufficiency of the evidence, the majority improperly overturns the jury’s verdict finding infringement.


Federal Circuit Splits on Validity of Means Plus Function Claim

Telcordia Technologies, Inc. v. Cisco Systems pic-100.jpg (Fed. Cir. 2010)

Chief Judge Rader and Judge Prost sparred over the level of explanation necessary to ensure that a means plus function (MPF) claim is found definite. The Patent Act (35 U.S.C. 112 p6) permits claim limitations written as a "means or step for performing a specified function." The statute provides that an MPF "claim [limitation] shall be construed to cover the corresponding structure, material, or acts described in the specification and equivalents thereof." However, the claim will be found indefinite and therefore invalid if the specification fails to include at least some structure that is clearly linked or associated with the claimed function. “The question is not whether one of skill in the art would be capable of implementing a structure to perform the function, but whether that person would understand the written description itself to disclose such a structure.” (Quoting Tech. Licensing Corp. v. Videotek, Inc., 545 F.3d 1316, 1338 (Fed. Cir. 2008)).

Telcordia's patent in this case is directed to a double-ring network that is designed to withstand either a line-cut or a failed node. One element of the claim requires a "monitoring means, associated with the first ring and the second ring, for evaluating the integrity of the multiplexed subrate communications on the first ring and the second ring."

Writing for the majority, Chief Judge Rader (joined by Judge Lourie) held that the claimed "monitoring means" had been properly described in the specification. The dissent cited the same precedent but could not find anything in the specification that links disclosed structures to the claimed function. In discussing the opinion, Foley's Hal Wegner described the opinion as "pitting the leader of the older generation [of Federal Circuit Judges] against a contender from the next generation."

Stats: About 15% of newly issued patent included at least one claim having an MPF limitation. And, of those patents that include an MPF limitation, about half recite fewer than five such limitations. It appears that attorneys are using MPF claim language primarily as a back-up. Longer claim-sets are more likely to include means-plus function language. Thus 21% of patents with above-average-sized claimsets (by character count) include a means-plus-function limitation while only 11% of patents with below-average-sized claimsets include an MPF limitation. Looking claim-by-claim, I found that only 3% of the recently issued patents include means-plus-function limitations in every independent claim. Patents with MPF terms are more frequently associated with non-assigned patents (usually individual inventors). Patents arising from certain countries are much more likely to include MPF limitations. The chart below looks at the most common foreign filing jurisdiction for priority claims and reports the percentage of US patents arising from those foreign filings that include MPF limitations. [More Data]


Claim Construction

PatentLawPic745Wavetronix v. EIS Electronic Integrated Systems (Fed. Cir. 2009)

Wavetronix’s patent covers a big brother sensor to monitor vehicle trafic and to ensure that drivers are properly using the carpool (high-occupancy vehicle) lane. EIS was accused of infringement but convinced the Utah-based district court to grant summary judgment of non-infringement.

On appeal, the Federal Circuit has affirmed – largely based on claim construction of the claim term “probability density function estimate” or PDFE used to define the traffic lanes.

The excerpted claim reads as follows: 1. … a method for defining traffic lanes, comprising … b. generating a probability density function estimation … of said selectable plurality of vehicles; and c. defining said traffic lanes … from said probability density function estimation.

Writing for the court, Judge Patel (sitting by designation from the N.D. of Cal.) construed PDFE to as “a finite data set large enough to approximate a function of a continuous variable whose integral over a region gives the probability that a random variable falls within the region.”

[Updated] That definition – requiring an approximation of a continuous variable – helps EIS. The EIS system can also automatically define the traffic lanes based on traffic data, but the company claims that its device does not do so with “probability analysis” but rather uses large binary bins. Based on this distinction Judge Patel held that the EIS system data is “too coarse” to be a PDFE.

Even in a close case such as this, the court held that the DOE cannot rescue the patentee because of the tight requirements of element-by-element application of the DOE and the doctrine of vitiation.

Blackboard: Federal Circuit Again Find Software-Related Means-Plus-Function Claims Invalid for Failing to Disclose Sufficient Structure

Blackboard v. Desire2Learn (Fed. Cir. 2009) 08-1368.pdf

Blackboard’s patent covers an internet-based educational support system and method. (U.S. Pat. No. 6,988,138). On summary judgment, the district court (Judge Clark, E.D. Tex.) found claims 1-35 invalid as indefinite, but a jury found found that Desire2Learn liable for infringement of claims 36-38. On appeal, the Federal Circuit agreed that Claims 1-35 are indefinite, and – after altering the claim construction – held that the remaining claims were also invalid as anticipated. pic-54.jpg

Means-Plus-Function: Blackboard’s seemingly broadest claim (claim 1) includes several means-plus-function clauses, including a “means for assigning a level of access and control.” The specification briefly discusses an “access control manager” (ACM) with an “access control list.” On appeal, however, the court found that brief description to be an insufficient “disclosure of the structure that corresponds to the claimed function” and consequently indefinite under 35 U.S.C. §112 ¶2. See In re Donaldson, 16 F.3d 1189 (Fed. Cir. 1994)(en banc).

“[W]hat the patent calls the ‘access control manager’ is simply an abstraction that describes the function of controlling access to course materials, which is performed by some undefined component of the system. The ACM is essentially a black box that performs a recited function. But how it does so is left undisclosed.”

Important for patent drafter, means-plus-function claims require disclosure in the specification even if the means are already well known in the art.

The fact that an ordinarily skilled artisan might be able to design a program to create an access control list based on the system users’ predetermined roles goes to enablement. The question before us is whether the specification contains a sufficiently precise description of the “corresponding structure” to satisfy section 112, paragraph 6, not whether a person of skill in the art could devise some means to carry out the recited function.

Because claims 2-35 all depend upon claim 1, they are all invalid as indefinite

Claim construction: At the trial, Blackboard’s expert could only identify one difference between claims 36-38 and the prior art. Namely, that the Blackboard patent identified a “single login” feature that allowed one user to have various roles within the system. “For example, Blackboard asserted that its claimed method would allow a graduate student who was a student in one course and a teacher in another to use a single login to obtain access to both courses and to obtain access to the materials for each course according to the graduate student’s role in each.” However, on appeal, the Federal Circuit determined that the claims do not actually require that feature — leading them to hold the claims invalid based primarily on the admissions of Blackboard’s own expert.

[O]nce the claims are properly construed, the conclusion of anticipation is dictated by the testimony of Blackboard’s own witnesses and the documentary evidence that was presented to the jury. Based on that evidence, and in the absence of a “single login” requirement in claims 36-38, it is clear that the prior art contains every limitation of those claims.

Defendant Desire2Learn wins a complete victory (after a few million in attorney fees).

Diverging Claim Constructions

Yesterdaypic-53.jpg raised a valuable discussion on claim construction with many excellent comments on the Cotropia-Bey article. The issue is obviously important since claim construction disputes arise in virtually every attempt to enforce a patent. One problem with claim construction in litigation is that the district court follows a completely different process of claim construction than do PTO examiners. The rules suggest that the two claim construction scopes should form concentric circles with the PTO’s broad construction and the Court’s narrower construction. The reality is that it is hard to form these concentric circles — especially with complex claims. And, it is virtually impossible to form concentric circles of construction using such distinct construction processes. Instead of nested constructions, in many cases the outcome of the district court tends to diverge from that suggested during prosecution.   

It seems odd that the patent prosecution process does not focus on determining the correct meaning of the claims. The better approach may well be to allow the original examination to determine the correct meaning of claims in a way that can be followed by courts down the line. I suspect that this approach would actually lead to more valid patents — especially if examiners applied a stronger hand on issues of indefiniteness.


  • Joel Miller’s 2006 JPTOS article in the Broadest Reasonable Interpretation standard is available here.
  • Mark Lemley and Dan Burke recently wrote a paper arguing that we should admit defeat and move to a central claiming system. Their analogy is that claims might be better used as sign-posts rather than fence-posts. [Link]
  • Lemley’s 2005 article on The Changing Meaning of Patent Claim Terms is also a good read. [Link]

The Unreasonableness of the Patent Office’s ‘Broadest Reasonable Interpretation’ Standard

Chris Cotropia (Richmond Law) and Dawn-Marie Bey (King & Spalding) have an interesting draft article out on the PTO’s “broadest reasonable interpretation” standard for interpreting claims during patent prosecution. The article notes that the increase in post-grant reviews (reexaminations) running concurrently with infringement litigation raises the stakes of the PTO’s standard.

From the abstract:

Although there has been much commentary on patent claim interpretation methodology in general, very little has been written about the unique interpretation approach the Patent Office employs. The courts, starting with the Court of Customs and Patent Appeals and continuing with the Federal Circuit, instruct the Patent Office to give every applied-for claim its ‘broadest reasonable interpretation’ (BRI) during patent examination. This Article explores this special standard and concludes that not only are the previously articulated rationales behind the BRI standard severely lacking, the standard is also contrary to both the patent statutes and the concept of a unitary patent system. The BRI standard additionally allows patent examiners to avoid difficult claim interpretation issues, leads to improper and uncorrectable denials of patent protection, and is incurably ambiguous.


When The Infringing Device only Temporarily Meets the Claim Limitations

PatentLawPic742Gemtron v. Saint-Gobain (Fed. Cir. 2009)

The Michigan-based district court found that Saint-Gobain’s refrigerator shelves infringe Gemtron’s patent No. 6,679,573 and awarded a permanent injunction against further infringement. The shelves were unique – primarily because the glass panel shelf securly snaps into its plastic frame rather than being held by adhesives. The claims required the plastic fram to be “relatively resiliant” so that the glass could snap into place.

The claim construction issue was interesting because it focused on timing. Saint-Gobain’s plastic frame was resiliant while still warm immediately after forming. However, it quickly hardened and became brittle afterward. The accused infringer argued that the limitation “‘relatively resilient’ should not mean ‘temporarily resilient immediately after cooking in an oven and before any opportunity to cool.’”

On appeal, the Federal Circuit affirmed – finding that the purpose of the resiliance (to install the glass panel) “suggests that the claimed resilience of the frame need only be exhibited during assembly.”

There is no discussion in the specification of any purpose for or value of the “relatively resilient” structural characteristic …, other than to facilitate assembly of the shelf. This indicates that the end edge portions of the frame have the claimed structural characteristic—“relatively resilient”—if they are able to deflect at the time the shelf is assembled, to “snap-secure” the glass panel within the frame.


  • Note: The permanent injunction was affirmed without comment.

Fractured Claim Construction

Agilent Tech., Inc. v. Affymetrix, Inc. (Fed. Cir. 2009)

Agilent’s microarray hybridization genetic analysis patent issued in 2003. After seeing those issued claims, Affymetrix amended a pending application by adding identical claims in order to provoke an interference. The Agilent patent has a priority date of 1998 while the Affymetrix application claims priority back to 1995. The Board of Patent Appeals and Interferences (BPAI) awarded priority to Affymetrix in 2006. That holding was upheld by a N.D. California district court in 2008.

Here, the Federal Circuit reverses – holding that Affymetrix cannot claim priority back to its 1995 filing because that original application “does not satisfy the written description requirement for the claims at issue.” Written description is particularly relevant in interference cases where one party typically copies claims from another patent document.

Claim Construction in an Interference: Several articles have been written on the complicated and ever-changing scope of a patent claim. At the PTO, claims are usually given their broadest reasonable meaning while in litigation, courts look for how a PHOSITA would interpret the scope, etc.. Phillips teaches that proper claim construction looks at the literal language of the claims as well as supporting information from the specification and prosecution history. In an interference, however, the copied claims originally came from another application.

Faced with a split of precedent, the Federal Circuit here decided to continue with multiple interpretations of an individual claim. Following Spina, the court holds that – for the purposes of the written description requirement – the newly added claims should be interpreted based on the specification and history of the opposing source application. However, following Rowe, the Federal Circuit held that for the purposes of novelty and nonobviousness, the newly added claims should be construed based on the specification and history of the amended application.

To be clear, as this court explained in Rowe, when a party challenges written description support for an interference count or the copied claim in an interference, the originating disclosure provides the meaning of the pertinent claim language. When a party challenges a claim’s validity under § 102 or § 103, however, this court and the Board must interpret the claim in light of the specification in which it appears.

This change in primary interpretative materials allowed the Federal Circuit to also change the claim construction and consequently hold that Affymetrix’s application “does not satisfy the written description requirement for the claims at issue.”


  • As a pending application, Affymetrix’s claims had no presumption of validity. “Thus, Agilent’s burden of proving a lack of written description in Affymetrix’s Besemer application is a simple preponderance of the evidence. Eli Lilly & Co. v. Aradigm Corp., 376 F.3d 1352, 1365 (Fed. Cir. 2004).”