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Manchak v. Chemical Waste Management

United States Court of Appeals for the Federal Circuit

December 6, 1999


Before Mayer, Chief Judge, Michel and Clevenger, Circuit Judges.

The opinion of the court was delivered by: Michel, Circuit Judge.

Sevenson Environmental Services, Inc. ("Sevenson") appeals from the judgment of the United States District Court for the District of Delaware entering a jury verdict that Sevenson literally infringed claims 1 and 2 of Frank Manchak, Jr.'s U.S. Patent No. 4,079,003 ("the '003 patent"). Sevenson also appeals the district court's alternative post-trial finding under Rule 49(a) of the Federal Rules of Civil Procedure that Sevenson infringed claims 1 and 2 under the doctrine of equivalents and the district court's award of damages and attorney fees to Manchak. Because the district court erred in its claim construction and thereby improperly found both literal and equivalent infringement, we reverse the judgment of the district court in all respects.


Manchak is the named inventor and owner of the '003 patent, entitled "Method of Transforming Sludge into Ecologically Acceptable Solid Material." Claims 1 and 2 recite a method for treating sludge with calcium oxide (commonly known as limestone or "quick lime"):

1. A method of transforming aqueous organic material containing sludge that may include virus and odor forming bacteria and toxic soluble compounds that are converted to substantially insoluble compounds in an alkaline environment into a solid, friable, and substantially odor free reaction product, said method comprising the steps of:

a. sequentially moving said sludge from a source thereof at a first rate;

b. sequentially moving calcium oxide from a source thereof at a second rate, with said second rate so related to said first rate that when sludge and calcium oxide are mixed an exothermic reaction is initiated in which said sludge and calcium oxide react with the evolution of steam to form a solid, friable, substantially odor free reaction product that has a pH of at least 12 and in which bacteria and virus initially present in said sludge are deactivated by said pH and the heat of said exothermic reaction, and said soluble toxic compounds initially present in said sludge are transformed to substantially water insoluble compounds due to the high pH of the mixture of said sludge and calcium oxide as they transform to said reaction product;

c. providing an elongate confined space that has first and second ends;

d. directing said sludge and calcium oxide at said first and second rates into said first end of said confined space;

e. concurrently mixing and moving the mixture of said sludge and calcium oxide in said confined space from said first end towards said second end thereof, with the rate of longitudinal movement of said mixture in said confined space being such that said exothermic reaction has transformed said mixture to said reaction product by the time said reaction product has reached said second end;

f. withdrawing said steam from said confined space; and

g. sequentially removing said reaction product from said second end of said confined space.

2. A method as defined in claim 1 in which said mixture is concurrently mixed and moved longitudinally in said confined space by rotating a number of longitudinally spaced, transversely and angularly disposed rigid surfaces within the confines of said confined space. (Emphasis added.)

Briefly summarized, sludge and calcium oxide simultaneously enter one end of an apparatus through two different openings and at two different rates. They are then mixed in the "confined space" of the apparatus to initiate an exothermic reaction. The reaction product exits the apparatus through a third opening at the opposite end, and the steam created by the reaction is withdrawn from the apparatus.

Sevenson, an environmental remediation firm, used the "Maectite process" in cleaning up the Marathon Battery Site in upstate New York. In the Maectite process, sludge is poured into a hopper covered by a screen to keep out branches and rocks. The hopper funnels the sludge onto a conveyor belt that in turn leads to a weigh belt. The weigh belt weighs the sludge and then dumps it into a second hopper. Lime is then poured into the second hopper at a rate dependent upon the weight of the sludge. The second hopper leads to a final conveyor belt, which feeds the sludge into an enclosed box-like structure called a "pugmill." Inside the pugmill, a series of intertwined rotating paddles mix the sludge with the calcium oxide and advance the mixture towards an opening on the other end. Notably, the pugmill has a safety screen on top that allows the steam formed by the exothermic reaction to freely escape. The pugmill forces the mixture out the second end for transport away from the site by truck or railcar.

In November 1995, Manchak brought a patent infringement suit in the United States District Court for the District of Delaware against six defendants. When ordered to select one defendant, Manchak chose Sevenson. The district court issued its claim construction opinion on May 1, 1997. On June 19, 1997, a jury found that Sevenson had literally infringed '003 claims 1, 2, 13, and 14 and awarded damages of $975,000. Because it found literal infringement, the jury skipped the questions of infringement by equivalents as the district court had instructed. *fn1

After the verdict, Sevenson renewed its motion for judgment as a matter of law of no literal infringement. On February 26, 1998, the district court granted Sevenson's motion with respect to claims 13 and 14, but denied it with respect to claims 1 and 2. The district court also invoked Rule 50(b) of the Federal Rules of Civil Procedure to find, in the alternative, that Sevenson had infringed claims 1 and 2 under the doctrine of equivalents. On June 26, 1998, after realizing that Manchak had never actually moved post-trial for judgment of infringement as a matter of law, the district court re-labeled its finding of infringement by equivalents as arising under Rule 49(a). The district court also declared the case to be "exceptional," and awarded Manchak $18,990.55 in attorney fees. This court has jurisdiction over this appeal under 28 U.S.C. § 1295(a)(1) (1994).


A district court's construction of disputed claim terms is a question of law subject to plenary review on appeal. See Cybor Corp. v. FAS Techs., Inc., 138 F.3d 1448, 1456, 46 USPQ2d 1169, 1174 (Fed. Cir. 1998) (en banc). This court owes no deference to a jury verdict based on an improper claim construction, especially where the correct construction of the claims is dispositive on the issue of infringement. See Strattec Security Corp. v. General Automotive Specialty Co., 126 F.3d 1411, 1419, 44 USPQ2d 1030, 1036 (Fed. Cir. 1997).

In its May 1, 1997 claim construction opinion, the district court construed the term "confined space" in claims 1 and 2 as:

An elongate space that must confine the reaction product of calcium oxide and sludge. However, steam produced as a result of the reaction between calcium oxide and water in the sludge need not be so confined.

Sevenson contends that the district court erroneously construed "confined space" as only confining the reaction product of calcium oxide and sludge. Sevenson argues that the claims themselves, the written description, and the prosecution history establish that the "confined space" must confine steam. Because the pugmills that Sevenson used in its Maectite process indisputably lack a steam-confining top, Sevenson maintains that it cannot literally infringe upon claims 1 and 2 of the '003 patent. We agree.

The plain language of the claims themselves demonstrates that the "confined space" must also confine steam. Nothing in claim 1 suggests that "confined space" be narrowly construed as confining only reaction product of calcium oxide and sludge, but not steam. "Without an express intent to impart a novel meaning to claim terms, an inventor's claims take on their ordinary meaning." York Prods., Inc. v. Central Tractor Farm & Family Ctr., 99 F.3d 1568, 1572, 40 USPQ2d 1619, 1622 (Fed. Cir. 1996). The step of "withdrawing said steam from confined space" in claim 1 also would make little sense if the steam were not confined in the space to begin with.

The district court's definition of "confined space" further conflicts with claims 5 and 7, which recite:

5. The method as defined in claim 1 in which said confined space is of such depth that a longitudinally extending space is provided in said confined space into which said steam can accumulate, and said longitudinally extending confined space in communication with a passage through which said steam may flow to the exterior of said confined space.

6. The method as defined in claim 5 which includes the further step of:

h. blowing a stream of air across said passage and substantially normal thereto to withdraw said steam from said longitudinally extending space.

7. The method as defined in claim 6 which includes the further step of:

i. directing the mixture of air and steam through a spray of water to remove foreign particled material from said steam prior to said air and uncondensed steam being discharged to the ambient atmosphere. (Emphasis added.)

Claim 5 requires that the "confined space" be of sufficient depth to allow steam to accumulate and provides a "passage" through which steam may "flow" to the exterior. These limitations presuppose a steam-confining top, but the only structure in claim 5 that can provide this top is the "elongate confined space" limitation of claim 1. Claim 5 does not otherwise add any new structure that would force steam to accumulate in, rather than passively rise out of, "said confined space." Claim 6 blows the steam out of the confined space via the passage provided in claim 5 to "withdraw" it. Claim 7 further recites the "discharge" of accumulated steam to the "ambient atmosphere" after washing away particulate matter with water. This limitation would also make little sense unless the "said confined space" of claim 1 already prevented the steam from entering the "ambient atmosphere."

The written description tends to confirm this interpretation. It mentions the term "confined" in only one other context, i.e., "sumps are covered with plastic sheet or other impervious sheet to confine the smell." '003 patent, col. 7, ll. 36-37 (emphasis added). Since an inventor is presumed to have intended a consistent meaning for a term used in different portions of the written description, Manchak's illustration of a plastic sheet as "confining" gases implies that the "confined space" should also "confine" steam.

Finally, the prosecution history also tends to reinforce our interpretation of "confined space" as also confining steam. During the prosecution of the '003 patent, the examiner cited U.S. Patent No. 3,476,873 to Liljegren ("the '873 patent"). The '873 patent teaches the treatment of sewage with lime involving the pre-treatment of the sewage in "one or more sedimentation and/or flotation pools." '873 patent, col. 2, ll. 38-39. To distinguish claim 1 over the '873 patent, Manchak explained that "applicant requires no sedimentation and/or flotation pools" and, more significantly, advised that "[d]uring the reaction steam is formed in the confined space and removed therefrom." (Emphasis added.) Logically, steam cannot be "formed in the confined space" if the "confined space" does not also confine steam. Moreover, unless confined, steam would hardly need to be "removed therefrom."

The district court's unusual construction of "confined space" primarily resulted from its oversight of two sound principles of patent law. First, the district court held that independent claim 1 could not read on any process for allowing steam to accumulate in the elongate space, since the accumulation of steam in such space was a limitation appearing only in dependent claim 5. As this court has previously recognized, however, "[i]t is axiomatic that dependent claims cannot be found infringed unless the claims from which they depend have been found to have been infringed." Wahpeton Canvas Co. v. Frontier, Inc., 870 F.2d 1546, 1553, 10 USPQ2d 1201, 1208 (Fed. Cir. 1989). The district court also improperly refused to consider the embodiment depicted in Figure 14 and described in columns 8 through 10 to aid its construction of "confined space," since it incorrectly assumed that the written description required more limitations than set forth in claim 1. The district court seemingly ignored this court's repeated statement that "[c]laims must be read in view of the specification, of which they are a part." Markman v. Westview Instruments, Inc., 52. F.3d 967, 976, 34 USPQ2d 1321, 1326 (Fed. Cir. 1995) (en banc), aff'd, 517 U.S. 370 (1996).

Manchak advances several arguments to defend the district court's interpretation of "confined space." First, Manchak notes that dependent claim 5 requires that steam accumulate in the "longitudinally extending space" created by adding depth to the "confined space." Manchak argues that if the "confined space" of claim 1 also confines steam, dependent claim 5 would be superfluous. Under the doctrine of claim differentiation, a claim should not ordinarily be construed in such a manner that would render a related dependent claim superfluous. See Comark Communications, Inc. v. Harris Corp., 156 F.3d 1182, 1187, 48 USPQ2d 1001, 1005 (Fed. Cir. 1998).

As we noted in Comark, however, "the doctrine of claim differentiation is not a hard and fast rule of construction." Id., 156 F.3d at 1187, 48 USPQ2d at 1005. Rather, the doctrine is inapplicable where one or more added limitations distinguishes the allegedly superfluous dependent claim from its parent independent claim. See Mantech Envtl. Corp. v. Hudson Envtl. Servs., 152 F.3d 1368, 1376, 47 USPQ2d 1732, 1739 (Fed. Cir. 1998). Here, claims 5, 6, and 7 are distinguishable from claim 1 by their respective additions of a passage and increased depth to create a "longitudinally extending space," blowing step (h), and directing and steam-discharging step (i).

Manchak also advances the well-known principle that "claims are not to be interpreted by adding limitations appearing only in the specification. . . . [A]lthough the specification may well indicate that certain embodiments are preferred, particular embodiments appearing in [the] specification will not be read into the claims when the claim language is broader than such embodiments." Electro Med. Sys. S.A. v. Cooper Life Sciences, 34 F.3d 1048, 1054, 32 USPQ2d 1017, 1021 (Fed. Cir. 1994) (citations omitted). Manchak argues that interpreting the "confined space" limitation as also confining steam would improperly incorporate the limitations of the preferred embodiment depicted in Figure 14 into claim 1.

We reject Manchak's characterization of our interpretation as erroneously reading limitations from the written description into the claim. Though columns 8 through 10 and Figure 14 of the '003 patent provide the only support for the method recited in claims 1 and 2, they nowhere describe a "confined space" as confining the reaction product, but not steam. As Sevenson properly notes, accepting Manchak's expansive construction of "confined space" would yield the anomaly of a specification that nowhere describes or depicts a single embodiment illustrating such breadth of interpretation. See Laitram Corp. v. Morehouse Indus., 143 F.3d 1456, 1463, 46 USPQ2d 1609, 1614 (Fed. Cir. 1993) (viewing it as relevant that nothing in the written description suggests the rejected construction). Furthermore, "confined space" is a limitation contained in claim 1, not a feature shown only in the specification. Thus, while the meaning of "confined space" must be gleaned from the claims and the written description, our construction does not import the term from the specification into claim 1, since it is already there.


Our Conclusion that the district court erred in its interpretation of "confined space," and thus in its denial of judgment as a matter of law of no literal infringement, does not end our inquiry. After the verdict, the district court alternatively found that Sevenson had infringed claims 1 and 2 of the '003 patent under the doctrine of equivalents. Though it originally invoked Rule 50(b) for its finding, the district court subsequently re-labeled its finding as arising under Rule 49(a) after realizing that Manchak had not moved for judgment as a matter of law of infringement before the verdict.

Manchak does not dispute the fact that the pugmills used in the Maectite process allow steam to freely escape into the ambient atmosphere. Given our interpretation of "confined space" as requiring a steam-confining top, no reasonable factfinder could find that the pugmills in this case are insubstantially different from the "confined space" of claim 1. See Sage Prods., Inc. v. Devon Indus., Inc., 126 F.3d 1420, 1424, 44 USPQ2d 1103, 1106 (Fed. Cir. 1997). Rather, a limitation -- a space that confines both reaction product and steam --is entirely missing in contravention of the All Limitations Rule. See Warner-Jenkinson Co. v. Hilton Davis Chem. Co., 520 U.S. 17, 29-30 (1997); Pennwalt Corp. v. Durand-Wayland, Inc., 833 F.2d 931, 939, 4 USPQ2d 1737, 1743 (Fed. Cir. 1987) (en banc). We therefore hold that the Sevenson cannot infringe claims 1 and 2 of the '003 patent under the doctrine of equivalents as a matter of law.



In light of our holdings that the pugmills used in the Maectite process cannot satisfy the "confined space" limitation of claims 1 and 2 either literally or under the doctrine of equivalents, we need not reach Sevenson's contention that the district court erred in its construction of "initiated" and in invoking Rule 49(a) or that Manchak's representations during the reexamination proceedings warrant remand. Moreover, as we did not consider Manchak's representations before the PTO in construing the "confined space" limitation, we decline Manchak's invitation to sanction Sevenson or dismiss this appeal due to Sevenson's inclusion of references to the reexamination proceedings in its briefs. Finally, the damages judgment naturally falls with our reversal of the infringement findings, as does the award of attorney fees. See Rodime PLC v. Seagate Tech., Inc., 174 F.3d 1294, 1308, 50 USPQ2d 1429, 1439 (Fed. Cir. 1999).

Accordingly, the judgment is in all respects reversed.

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