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December 13, 2009

So Unlike Concrete

In an extremely messy patent case involving claim construction (and correction), noninfringement, invalidity, laches, indefiniteness, trade secrets, and topped with several business torts, Ultimax Cement had its quick-set concrete patents crumble by a sledgehammer summary judgment at district court, and so Ultimax sought repair at the CAFC. The foundation of the patent problem: lack of careful proofreading by the prosecutor.

Ultimax Cement et al v. CTS Cement et al (CAFC 2008-1218, -1439) precedential

The patents in suit: 4,957,556; 6,113,684; and 6,406,534.

Claim Construction

The claim construction leading to non-infringement was set by defining the term "soluble CaSO4 anhydride," which should have read "anhydrite."

The court defined "anhydride," primarily using a dictionary, as "a compound formed from an acid by removal of water." '684 Indefiniteness and '556 Noninfringement and Laches Opinion, 2004 U.S. Dist. Lexis 29580, at *41. The court reasoned that, if the claim drafter had intended to refer to calcium sulfate from which water has been removed, which was Ultimax's interpretation, it would have used the term "anhydrous CaSO4" or "anhydrite," which is a specific term for anhydrous calcium sulfate. Id... Even though one skilled in the art might realize that the drafter intended the claim to refer to "anhydrite" instead of "anhydride," the court held that it could not substitute terms, as that would constitute redrafting the claims, which was forbidden even when the failure to substitute terms would lead to a strange result. Id. Thus, according to the court, the claim term "soluble CaSO4 anhydride" required that the compound include not only calcium sulfate, but also an acid from which water has been removed. Because CTS's cement did not contain an acid from which water had been removed, the court granted summary judgment of noninfringement. Id. at *45.

Ultimax argued context.

According to Ultimax, the court erroneously used the stand-alone definition of "anhydride," without context... Ultimax argues, the court should have adopted a definition consistent with the specification and the art.

The CAFC agreed with Ultimax.

We begin a claim construction analysis by considering the language of the claims themselves. See Phillips v. AWH Corp., 415 F.3d 1303, 1314 (Fed. Cir. 2005) (en banc). However, "claims must be read in view of the specification, of which they are a part." Id. at 1315 (quotation marks omitted). "[A] court should also consider the patent's prosecution history, if it is in evidence. . . . Like the specification, the prosecution history provides evidence of how the [Patent Office] and the inventor understood the patent." Id. at 1317 (citations and quotation marks omitted).

Furthermore, courts may "rely on dictionary definitions when construing claim terms, so long as the dictionary definition does not contradict any definition found in or ascertained by a reading of the patent documents." Id. at 1322-23 (quoting Vitronics Corp. v. Conceptronic, Inc., 90 F.3d 1576, 1584 n.6 (Fed. Cir. 1996)). However, "[a] claim should not rise or fall based upon the preferences of a particular dictionary editor, or the court's independent decision, uninformed by the specification, to rely on one dictionary rather than another." Id. at 1322. Indeed, "the authors of dictionaries or treatises may simplify ideas to communicate them most effectively to the public and may thus choose a meaning that is not pertinent to the understanding of particular claim language. The resulting definitions therefore do not necessarily reflect the inventor's goal of distinctly setting forth his invention as a person of ordinary skill in that particular art would understand it." Id. (internal citation omitted).

Here, without the benefit of our opinion in Phillips, which was issued after the district court's opinion in this case, the court erroneously relied on expert testimony and a single dictionary definition to the exclusion of other dictionary definitions and, most importantly, the context in which the term was used within the claim and the specification. Although the word "anhydride" appears in the term "soluble CaSO4 anhydride," its proper construction requires consideration of the context of the rest of the term. "Anhydride," when placed next to "CaSO4," is intended as a modifier, modifying "CaSO4," or "calcium sulfate." In other words, the term refers to calcium sulfate from which any associated water has been removed. Indeed, dictionaries other than that relied on by the court allow "anhydride" to refer to a compound other than one obtained by removing water from an acid, based on context. For example, the definition that Plaintiffs proffered defines "anhydride" as "[a] chemical compound formed from another, often an acid, by the removal of water." J.A. 3749 (emphasis added) (citing definition from The American Heritage Dictionary of the English Language (2000)). Thus, especially in light of the ambiguity of the proffered dictionary definitions, the context must define what compound has had water removed. Here it is calcium sulfate, not an acid.

The context of the entire specification further supports the conclusion that "soluble calcium sulfate anhydride" means "soluble anhydrous calcium sulfate."

Getting a claim term right isn't a rewriting.

Furthermore, contrary to the district court's conclusion, interpreting the claim term to mean "soluble anhydrous calcium sulfate" is not rewriting the claim or correcting a typographical error. The drafters could not have intended to claim "soluble calcium sulfate anhydrite," as that would have been redundant because the word "anhydrite" itself means "anhydrous calcium sulfate."...Thus, interpreting the claim in that way merely restates its plain meaning.

Hence noninfringement was vacated, and the case remanded.


The CAFC panel found summary judgment on laches inappropriate because "genuine issues of material fact precluded summary judgment that the '556 patent is unenforceable due to laches, as it is not clear that Ultimax knew or should have known of CTS's alleged infringement before it conducted discovery on the '684 patent in 2002."

Summary judgment is appropriate only where "there is no genuine issue as to any material fact and . . . the moving party is entitled to a judgment as a matter of law." Fed. R. Civ. P. 56(c). Thus, if genuine issues of material fact preclude summary judgment of laches, "we need not apply [the abuse of discretion] standard[ ] of review" that generally applies to laches. Wanlass v. Fedders Corp., 145 F.3d 1461, 1463 (Fed. Cir. 1998).

To prevail on a defense of laches, CTS must prove two elements: (1) Plaintiffs delayed filing suit for an unreasonable and inexcusable length of time from the time they knew or reasonably should have known of their claim against CTS, and (2) the delay operated to the prejudice or injury of CTS. Id. at 1463-64 (quoting A.C. Aukerman Co. v. R.L. Chaides Constr. Co., 960 F.2d 1020, 1032 (Fed. Cir. 1992) (en banc)). Plaintiffs' delay "is measured from the time [they] knew or reasonably should have known of [CTS's] alleged infringing activities to the date of suit." Id. (citing A.C. Aukerman, 960 F.2d at 1032). "[T]he underlying critical factors of laches are presumed upon proof that the patentee delayed filing suit for more than six years after actual or constructive knowledge of the defendant's alleged infringing activity." Id. (quoting A.C. Aukerman, 960 F.2d at 1035-36).

The only issue for deciding laches is what a patent holder "knew or should have known."

CTS does not dispute that Ultimax could not have tested CTS's product for the presence of soluble anhydrite. Without access to CTS's internal procedures, Kunbargi could not have investigated CTS's methods to determine infringement. Even Kunbargi's hiring of a private investigator led to no conclusive result that CTS's products infringed the '556 patent. An infringer does not escape liability merely by infringing in secret. Ultimax could only have asserted infringement of the '556 patent upon a reasonable belief that CTS infringed all of the limitations of the claims, including the limitation requiring soluble anhydrite. See Antonious v. Spalding & Evenflo Cos., 275 F.3d 1066, 1074 (Fed. Cir. 2002) ("[A]n attorney violates [Fed. R. Civ. P.] 11(b)(3) when an objectively reasonable attorney would not believe, based on some actual evidence uncovered during the prefiling investigation, that each claim limitation reads on the accused device either literally or under the doctrine of equivalents."). Thus, because Ultimax alleges, and CTS does not rebut, that Ultimax had no such reasonable belief before 2002, summary judgment of laches should have been precluded.

Although, as CTS argues and the district court found, twelve (or thirteen) years is a long time between patent issuance and filing suit, the only time relevant to the laches presumption is that after Ultimax knew or should have known of the allegedly infringing product. In the case of a claim limitation whose presence is undetectable in a finished product, it is reasonable that Ultimax might not have known or been able to find out whether CTS infringed.

We reverse the court's grant of summary judgment of laches and remand for a trial on laches relating to the '556 patent.


A missing comma lead the district court finding indefiniteness. "(f cl)" should have been "(f, cl)." Further, there was a complex formula for "crystal X" that caused consternation. Again, the CAFC gave Ultimax mortar for rebuilding its case.

Under 35 U.S.C. ยง 112, second paragraph, the "specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention," which is known as the definiteness requirement. Id. "Claims are considered indefinite when they are not amenable to construction or are insolubly ambiguous. Thus, the definiteness of claim terms depends on whether those terms can be given any reasonable meaning. Indefiniteness requires a determination whether those skilled in the art would understand what is claimed." Young, 492 F.3d at 1346 (internal citations and quotations marks omitted). The purpose of the definiteness requirement is to ensure that "the claims, as interpreted in view of the written description, adequately perform their function of notifying the public of the scope of the patentee's right to exclude." Honeywell Int'l, Inc. v. Int'l Trade Comm'n, 341 F.3d 1332, 1339 (Fed. Cir. 2003) (quotation marks omitted).

Merely claiming broadly does not render a claim insolubly ambiguous, nor does it prevent the public from understanding the scope of the patent. See In re Gardner, 427 F.2d 786, 788 (CCPA 1970) ("Breadth is not indefiniteness.").

The CAFC tried to solidify the guide to claim correction by a court for "an obvious typographical error."

We have held that "[a] district court can correct a patent only if (1) the correction is not subject to reasonable debate based on consideration of the claim language and the specification and (2) the prosecution history does not suggest a different interpretation of the claims." Novo Indus., L.P. v. Micro Molds Corp., 350 F.3d 1348, 1357 (Fed. Cir. 2003). Those determinations must be made from the point of view of one skilled in the art. "Claim definiteness is analyzed not in a vacuum, but always in light of the teachings of the prior art and of the particular application disclosure as it would be interpreted by one possessing the ordinary level of skill in the pertinent art." Energizer Holdings v. Int'l Trade Comm'n, 435 F.3d 1366, 1370 (Fed. Cir. 2006) (quotation marks omitted). Thus, although courts cannot "rewrite claims to correct material errors," id., if the correction is not subject to reasonable debate to one of ordinary skill in the art, namely, through claim language and the specification, and the prosecution history does not suggest a different interpretation, then a court can correct an obvious typographical error.

Again, the district court is reversed.


In what appears refreshing candor, Ultimax practically admitted invalidity of some claims.

[A]t oral argument, Ultimax stated, with respect to claims 10 and 11 of the '534 patent, that it was not concerned with the court's finding of invalidity of claims 10 and 11.


Other issues, not germane to the patents, other than Ultimax unsuccessfully trying to amend its complaint three times (upheld), are left to the studious case law reader to glean from the ruling.

Concrete is an environmentally obnoxious product.

Posted by Patent Hawk at December 13, 2009 1:04 AM | Claim Construction


The Appeals Court stated that the District Court ruled on SJ that the patent was 'unenforceable' due to laches.

From the District Court Ruling:

"Laches offers a defense to infringement which has occurred prior to the filing of the suit. Chisum 19.05."

How does one arrive at unenforceability from that?

Posted by: errata? at December 14, 2009 2:35 PM

A very odd fact on the claim construction issues relating to infringement and indefiniteness was the refusal of the district court to even heed the observations of its neutral court-appointed expert that: (1) "anhydride" likely meant "anhydrite" in this context and thus "soluble calcium sulfate anhydride" should be construed to refer to "soluble anhydrous calcium sulfate"; and (2) omission of the comma between "f" and "cl" was an obvious "claim drafting error." Fortunately for the patentee, the Federal Circuit panel came to the rescue on these claim drafting goofs.

Posted by: EG at December 15, 2009 6:12 AM


Actually, treating a successful laches defense as rendering the patent unenforceable against a particular party is probably OK. This is similar to a misuse defense which renders the patent unenforceable (not invalid).

Posted by: EG at December 15, 2009 6:19 AM