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 ...