Parties failed to overcome "heavy presumption" that claim term carries its ordinary and customary meaning.

Judge Antoon resolved the parties' claim construction dispute of certain claim terms. First, "calcium carbonate in aqueous suspensions or dispersions of calcium carbonate" was construed as "insoluble particles of calcium carbonate distributed in water or calcium carbonate in a system with two or more distinct phases consisting of finely divided particles dispersed throughout a bulk substance." Second, "molar ratio" is construed as "a ration comparing a number of urea molecules to a number of hydrochloric acid molecules."

EMS seeks a declaratory judgment that it didn't infringe U.S. Patent 5,672,279. Generally, the' 279 Patent involves the removal of unwanted calcium carbonate using urea hydrochloride.

The original claims recited the removal of "undesirable solids." In response to a rejection during examination, the applicant changed "undesirable solids" to include the removal of "calcium carbonate in aqueous suspension or dispersions of calcium carbonate." The Court noted that this amendment did not change the ordinary and customary meaning of "calcium carbonate in aqueous suspensions or dispersions of calcium carbonate" (although the patentee disclaimed the subject matter that lied between those 2 terms).

PSL sought a claim construction that covered a preferred embodiment from the specification (and also arguably covers EMS's allegedly infringing products.) The Court found that that construction altered the ordinary and customary meaning of the claim term. EMS argued that prosecution history estoppel should limit the scope of the '279 claims. The Court did not agree with either party and adopted the construction above. The jury will decide whether EMS's products fall within the scope of the claim.

Environmental Manufacturing Solutions, LLC v. Peach State Labs, Inc., Case No. 6:09-CV-395 (M.D. Fla. Sept. 21, 2010) (J. Antoon)