US Philips v. Iwasaki (Fed. Cir. 2007)
Philips sued Iwasaki for infringement of its patents covering mercury-tungsten halogen light. The district court awarded summary judgment of non-infringement to Iwasaki.
Vitiation and the Doctrine of Equivalents: The asserted patent claims a target concentration of 1.6 ± 0.4 × 10-4 µmol/mm3. Based on that claim language, the district court ruled that the claim was “intended to establish the demarcation of boundaries [with] the type of precision that is closely analogous to the metes and bounds of a deed of real property.” Thus, according to the court, allowing the claim to cover any concentration outside of the clearly claimed limits would vitiate the limitation.
On appeal, the CAFC rejected the notion that an expanded numerical range would vitiate the claim language.
“A reasonable juror could make a finding that a quantity of halogen outside that range is insubstantially different from a quantity within that range without “ignore[ing] a material limitation” of the patent claim.”
This decision conforms to prior decisions that allow equivalents for numerical ranges, but not for other limits (such as a claimed “majority.” Moore).
Notice of Infringement: 35 U.S.C. § 287(a) provides that damages for patent infringement only begin to accrue once the infringer was “notified of the infringement.” (Marking constitutes constructive notice). Notice requires a charge of infringement directed to a specific product, device, or action. The notice must also normally include the patentee’s identity. Here, the infringement letter (sent by “Mr. Rolfes”) did not specifically indicate that Philips was the assignee, but the court found notice sufficient because (1) Philips was correctly listed as the assignee of the patent and (2) Philips had granted the sending party the “responsibility for licensing and enforcing” the patent. Thus, Philips may collect damages from the date of receipt of the letter.
- Rounding in Claim Construction: “‘1.0’ may be said to have more significant digits than ‘1’ with no decimal point. Because [the claimed] ‘10-6’ and ‘10-4’ are simply the numbers 0.000001 and 0.0001 expressed as powers of ten, the claim language provides no basis for inferring any level of precision beyond the single digit ‘1.’ The way that power-of-ten quantities are used in the specification, discussed supra, confirms that the quantities of halogen described by the claims are not intended to be more precise.” — Why does this matter — Less precision means that the accused product may still literally infringe due to rounding.
- Approximately: “[T]erms like ‘approximately’ serve only to expand the scope of literal infringement, not to enable application of the doctrine of equivalents.”