At trial, the parties focused their dispute on whether Brotech's third component was a precipitant within the terms of the claims. Because all of the asserted claims contained at least one of these elements, the trial court granted judgment of noninfringement in favor of Brotech. In Symbol Technologies , this court upheld a finding of infringement where the patentee's expert witness presented a claim chart identifying particular components of the accused device with each claimed element. Beyond the claim chart, the expert in Symbol Technologies presented no detailed analysis linking the particular parts of the accused device with the claimed elements. To show literal infringement of a patent, a patentee must supply sufficient evidence to prove that the accused product or process meets every element or limitation of a claim.
Infringement requires proof by a preponderance of the evidence.
See SSIH Equip. This court reviews a trial court's factual infringement determination for clear error. In this case, the district court determined that the patentee had not shown that the accused process included either of two limitations found in the patent claims. While an expert may testify to the ultimate issue in a case without giving the basis for that opinion, Fed. Nothing in the rules or in our jurisprudence requires the fact finder to credit the unsupported assertions of an expert witness.