When asserting doctrine of equivalents (“DOE”) infringement contentions, questions often arise as to how much detail is required under the local patent rules. Patentees have argued that a detailed DOE element-by-element disclosure is required only when the Court first determines that the claims do not literally infringe. While the local patent rules often do not expressly state that a patentee must provide an element-by-element DOE disclosure, several courts have required such a detailed DOE disclosure prior to any ruling on literal infringement.

In Ameranth, Inc. v. Pizza Hut, Inc. et al. (.pdf), 2013 WL 3894880 (S.D. Cal. July 26, 2013), the Court found that a patentee’s initial infringement contentions must include a substantive, DOE element-by-element disclosure under the local patent rules.

In the U.S. District Court for the Southern District of California, Local Patent Rule 3.1e requires that each infringement contention state, “[w]hether each element of each asserted claim is claimed to be literally present and/or present under the doctrine of equivalents in the Accused Instrumentality.” In an effort to expressly comply with the rule, the patentee included this generic statement for each claim element: “If this element is not found to be literally present, it is present under the doctrine of equivalents.” The Court ruled that such a generic statement is inadequate under the rules and must be restated with more substantive detail.

Although the Court conceded there was some uncertainty in the law, it was persuaded by several recent opinions from the U.S. District Court for the Northern District of California holding that a patentee must substantively describe the alleged similiarities under the DOE to particular claim elements. Id. at * 5 (citing Optimum Path, LLC v. Belkin Int’l, Inc., 2011 WL 1399257, *8 (N.D. Cal. April 12, 2011) and Nazomi Communs., Inc. v. Nokia Corp.,, 2013 WL 3146796, *5 (N.D. Cal. June 18, 2013)) The Court reasoned that such a detailed element-by-element disclosure was supported by the policy behind the local patent rules to “crystallize … theories of the case early in the litigation….” O2 Micro Int’l, Ltd. v. Monolithic Power Sys., 467 F.3d 1355, 1364 (Fed. Cir. 2006)

Key Takeaway:

When asserting initial DOE infringement contentions, a patentee should research the relevant case law to determine whether the Court will require more than literal compliance with the local patent rule.