The Federal Circuit’s decision in VLSI Technology LLC v. Intel Corporation, Case No. 24-1772 (Fed. Cir. Apr. 14, 2026), is a significant reminder that procedural decisions made early in patent litigation can later become outcome determinative. In a partially precedential opinion authored by Chief Judge Moore, the court reversed multiple summary judgment rulings that had wiped out VLSI’s infringement case involving U.S. Patent No. 8,566,836, while affirming the exclusion of certain damages theories under the Northern District of California’s local patent rules.
The opinion touches several recurring themes in modern patent litigation:
- the consequences of pretrial stipulations,
- territorial limits on infringement under 35 U.S.C. § 271,
- the high bar for prosecution disclaimer,
- capability-based infringement theories for apparatus claims, and
- increasingly strict enforcement of patent local rule disclosure requirements for damages theories.
For patent litigators, the case illustrates how seemingly administrative agreements and discovery disclosures can later control substantive liability outcomes. Charles Gideon Korrell notes that the Federal Circuit’s willingness to strictly enforce the parties’ stipulation reflects a broader trend toward holding sophisticated litigants to the strategic positions they voluntarily adopt during case management.
The Patent and District Court Proceedings
The patent at issue concerned multicore processors and selecting which processor core should execute a task based on measured performance characteristics.
The asserted method claims generally required:
- measuring processing speed parameters for multiple cores,
- storing those measurements, and
- selecting the fastest core for certain single-core tasks.
The asserted apparatus claims similarly required cores with performance measurement circuitry and storage used for selecting appropriate cores.
The district court granted summary judgment of noninfringement on two independent grounds:
- extraterritoriality, and
- rejection of VLSI’s doctrine of equivalents theory.
The court also struck portions of VLSI’s damages expert testimony relating to net present value (“NPV”) and value per unit (“VPU”) royalty theories.
The Federal Circuit reversed most of the liability rulings.
The Pretrial Stipulation Became Outcome Determinative
The most important aspect of the opinion may be the Federal Circuit’s treatment of the parties’ stipulation concerning U.S. nexus.
The parties had agreed that:
“seventy percent (70%)” of qualifying accused products and activities would “be deemed to have a United States nexus as required by each subsection of 35 U.S.C. § 271.”
The district court nevertheless concluded that VLSI failed to establish the necessary domestic conduct because certain measurement-related activities occurred overseas.
The Federal Circuit disagreed.
Chief Judge Moore emphasized that the stipulation expressly required the technical infringement determination to occur “without regard to geographic considerations.” The court held that the stipulation unambiguously established the required U.S. nexus once the technical claim limitations were satisfied.
Intel attempted to characterize the agreement as merely a damages-accounting mechanism, but the Federal Circuit rejected that interpretation because the stipulation expressly referenced § 271 itself, which governs infringement rather than damages.
The court’s reasoning relied heavily on ordinary contract principles governing stipulations. Citing Kearns v. Chrysler Corp., the panel refused to “rescue” Intel from a litigation position it had voluntarily adopted earlier in the case.
This portion of the decision is especially important for complex patent cases involving global supply chains, overseas testing, or distributed manufacturing operations. Parties frequently enter broad stipulations to streamline proof burdens involving foreign conduct, sales attribution, or damages allocation. VLSI demonstrates that such agreements can later override narrower litigation positions advanced at summary judgment.
Charles Gideon Korrell believes this portion of the opinion may influence how defendants approach early stipulations in large multi-patent cases. Parties may become substantially more cautious before agreeing to generalized nexus or attribution frameworks that could later foreclose territoriality defenses.
Apparatus Claims and Capability-Based Infringement
The Federal Circuit separately reversed summary judgment regarding the apparatus claims.
The district court had concluded that VLSI failed to show the accused products were “reasonably capable” of practicing the claimed measuring functionality within the United States.
Intel argued the claimed functionality only occurred when the accused processors were connected to external automated testing equipment (“ATE testers”) used overseas during manufacturing.
The Federal Circuit rejected that approach.
Relying on Gemtron v. Saint-Gobain and Silicon Graphics v. ATI Technologies, the court emphasized that the relevant question for apparatus claims is whether the accused products possess the structural capability to perform the claimed functions without requiring product modification.
Importantly, the panel distinguished between:
- requiring external operational inputs, versus
- requiring actual structural modification of the accused product.
That distinction mattered because VLSI introduced evidence that Intel’s processors already contained built-in performance measurement circuitry, including BIST and PBIST functionality.
Accordingly, factual disputes existed regarding whether the accused products inherently possessed the claimed capabilities.
This analysis aligns with earlier Federal Circuit authority recognizing that an accused apparatus may infringe if it contains the structural means necessary to perform the claimed function, even if additional operational context or software activation is required.
For semiconductor and hardware cases, this portion of the opinion reinforces the continuing importance of architectural evidence showing embedded circuitry or latent functionality.
The Court Reinforces the High Standard for Prosecution Disclaimer
The Federal Circuit also rejected the district court’s application of prosecution disclaimer.
The dispute centered on claim 10, an apparatus claim that did not expressly contain an “upon identifying” limitation found in certain method claims.
The district court imported that limitation into claim 10 based on prosecution history statements discussing task identification and core selection.
The Federal Circuit reversed, emphasizing once again that prosecution disclaimer requires “clear and unmistakable” disavowal.
The court carefully parsed three prosecution statements cited by Intel and concluded that none clearly imposed the temporal sequencing limitation adopted by the district court.
Chief Judge Moore stressed that ambiguity defeats disclaimer:
“Because this statement is, at best, ambiguous or amenable to multiple reasonable interpretations, prosecution disclaimer is not established.”
The opinion fits squarely within a long line of Federal Circuit cases resisting aggressive prosecution disclaimer arguments absent unmistakable surrender language. Cases such as Technology Properties v. Huawei, Elbex Video, and Phillips v. AWH continue to shape this doctrine.
Charles Gideon Korrell notes that this section of the opinion serves as another warning against over-reading prosecution history excerpts divorced from the actual claim language. The Federal Circuit repeatedly returns to the principle that disclaimer must be explicit, not inferred from loosely worded advocacy statements.
Strict Enforcement of Damages Disclosure Rules
Although VLSI prevailed on most liability issues, the Federal Circuit affirmed the exclusion of certain damages theories.
The district court had struck portions of Dr. Sullivan’s expert opinions because VLSI’s Patent Local Rule 3-8 disclosures inadequately disclosed the factual bases and calculations underlying the NPV and VPU theories.
The Federal Circuit found no abuse of discretion.
The opinion emphasized:
- vague references to internal documents,
- lengthy string citations,
- failure to identify specific figures later relied upon by the expert, and
- prior court warnings regarding inadequate damages disclosures.
The court nevertheless noted that VLSI retained other damages theories through another expert witness, meaning the case would proceed on remand with damages evidence still available.
This portion of the decision continues the trend toward increasingly rigorous enforcement of patent local rules governing damages disclosures. Northern District of California judges, in particular, have become far less tolerant of broad placeholder damages contentions followed by materially expanded expert analyses later in discovery.
Patent plaintiffs increasingly must provide concrete economic methodologies and supporting calculations far earlier in litigation than was once common practice.
Practical Implications
The opinion has several practical implications for patent litigators.
First, litigation stipulations matter. Courts may strictly enforce them according to their plain language, even where doing so later undermines a party’s preferred merits arguments.
Second, capability-based infringement theories remain viable for apparatus claims when accused products contain embedded structural functionality, even if external systems are involved during operation.
Third, prosecution disclaimer remains difficult to establish. Courts continue requiring truly unambiguous disavowal language before narrowing claim scope beyond the claim text itself.
Fourth, patent local rule compliance continues to become more exacting, especially regarding damages theories.
Charles Gideon Korrell believes the case is particularly notable because it combines substantive patent law with procedural litigation management issues. Many major patent cases are increasingly won or lost through discovery positioning, disclosure obligations, stipulations, and claim-construction framing long before trial occurs.
The Federal Circuit’s mixed ruling reflects that reality. VLSI successfully revived its infringement case, but still permanently lost portions of its damages presentation because of disclosure deficiencies that arose during pretrial proceedings.