MyPaq Holdings v. Samsung: Federal Circuit Affirms Patent Unpatentable
MyPaq Holdings Ltd. sought to defend US7403399B2 — covering active primary-sided circuit arrangements for switch-mode power supplies — against Samsung Electronics. The Federal Circuit affirmed the unpatentability finding in a Rule 36 summary affirmance, closing the appeal after 538 days without a written opinion.
Federal Circuit summarily affirms invalidation of MyPaq power supply patent
MyPaq Holdings Ltd., the holder of US7403399B2 covering an active primary-sided circuit arrangement for a switch-mode power supply, appealed to the United States Court of Appeals for the Federal Circuit under case number 23-2022. The appeal was filed on 15 June 2023 and targeted a prior validity determination — recorded on the basis of unpatentability — against Samsung Electronics Co., Ltd., one of the world’s largest consumer electronics manufacturers.
On 4 December 2024, the Federal Circuit issued a Rule 36 judgment affirming the lower tribunal’s finding. A Rule 36 affirmance is a summary disposition in which the appellate court, having fully considered the matter, finds no reversible error warranting a written opinion. The practical effect is that the cancellation or invalidity of US7403399B2 is now final at this appellate level, leaving MyPaq without enforceable rights in the claims at issue.
The 538-day duration is broadly consistent with contested Federal Circuit appeal timelines. The use of Rule 36 suggests the panel found the lower tribunal’s reasoning sufficiently clear and correct to require no elaboration — a signal that the patentability challenge was well-grounded. The absence of a written opinion means the evidentiary record and claim construction rationale from the underlying proceeding remain the definitive public analysis of why these claims failed.
Filing to Unpatentable in 538 days
538 days from filing to Federal Circuit judgment — consistent with standard appeal timelines
Federal Circuit affirms: what the Rule 36 ruling means for both parties
Rule 36 affirmance: no reversible error found below
A Federal Circuit Rule 36 judgment affirms the lower tribunal’s decision without a written opinion. The court issues this only when it is satisfied that no reversible error occurred — meaning the record, claim construction, and prior art analysis below were sufficiently sound to require no further elaboration. It carries full precedential weight for the parties, though it creates no citable precedent for third parties.
Summary affirmance — no written opinionUS7403399B2 is cancelled — MyPaq loses enforceability
For MyPaq Holdings, the Rule 36 affirmance exhausts the appellate remedy at this level. The patent’s claims have been adjudged unpatentable, and that finding is now confirmed by the Federal Circuit. MyPaq cannot enforce US7403399B2 against Samsung or any other party based on the invalidated claims. Further recourse would require a petition for rehearing or certiorari to the Supreme Court — both long-shot options with narrow grounds.
Patent rights extinguishedSamsung secures freedom to operate on this patent
Samsung Electronics successfully defended the unpatentability challenge through to final Federal Circuit judgment. With the patent affirmed as unpatentable, Samsung and the broader market gain confirmed freedom to operate with respect to the active primary-sided switch-mode power supply circuit arrangements covered by US7403399B2. The Rule 36 affirmance offers Samsung a clean and final resolution without creating new appellate law that could be cited against it elsewhere.
Freedom to operate confirmedPower supply IP landscape: one fewer blocking patent for competitors
Switch-mode power supply technology underpins smartphones, computing hardware, and consumer electronics broadly — all core Samsung product categories. The cancellation of US7403399B2 removes a potential licensing or litigation vector for this circuit topology. For competitors and suppliers active in power management IC design, the ruling is consistent with a trend of patent assertion challenges in this space being resolved at the PTAB/Federal Circuit level rather than through district court jury trials.
Reduced patent assertion riskFull party and counsel information
| Role | Name | Type | Detail |
|---|---|---|---|
| Plaintiff | MYPAQ HOLDINGS LTD. | Company | Patent holding company — holder of US7403399B2 covering switch-mode power supply circuitsSearch in Eureka ↗ |
| Defendant | Samsung Electronics Co., Ltd. | Company | Samsung Electronics Co., Ltd. — global consumer electronics and semiconductor manufacturerSearch in Eureka ↗ |
| Plaintiff counsel | James Carmichael | Attorney | Counsel for MYPAQ HOLDINGS LTD.Search in Eureka ↗ |
| Plaintiff counsel | Minghui Yang | Attorney | Counsel for MYPAQ HOLDINGS LTD.Search in Eureka ↗ |
| Plaintiff counsel | Stephen McBride | Attorney | Counsel for MYPAQ HOLDINGS LTD.Search in Eureka ↗ |
| Plaintiff law firm | Carmichael IP PLLC | Law Firm | Representing MYPAQ HOLDINGS LTD.Search in Eureka ↗ |
| Defendant counsel | Eliot Damon Williams | Attorney | Counsel for Samsung Electronics Co., Ltd.Search in Eureka ↗ |
| Defendant counsel | Eric J. Faragi | Attorney | Counsel for Samsung Electronics Co., Ltd.Search in Eureka ↗ |
| Defendant counsel | Neil P. Sirota | Attorney | Counsel for Samsung Electronics Co., Ltd.Search in Eureka ↗ |
| Defendant law firm | Baker Botts LLP | Law Firm | Representing Samsung Electronics Co., Ltd.Search in Eureka ↗ |
| Presiding judge | Judge N/A | Judge | Court of Appeals for the Federal CircuitSearch in Eureka ↗ |
Official order — verbatim text
The Federal Circuit’s order — ‘AFFIRMED. See Fed. Cir. R. 36’ — is the court’s most definitive form of summary affirmance. Issued under Rule 36, it confirms the panel reviewed the full record and found no reversible error in the underlying unpatentability determination. No written reasoning accompanies the order, meaning the lower tribunal’s claim construction and prior art analysis stand as the final analytical record. For MyPaq, there is no adverse legal precedent created for third parties, but the patent itself is fully and finally cancelled as against Samsung.
US7403399B2 — Active Primary-Sided Switch-Mode Power Supply Circuit
US7403399B2, filed under application number US11/394734, protects an active primary-sided circuit arrangement for a switch-mode power supply. Switch-mode power supplies (SMPS) are the dominant technology for efficient DC power conversion in consumer electronics, computing, and telecommunications equipment. A primary-sided active circuit configuration relates to control and switching topology on the input side of the transformer — a technically specific claim scope in a crowded prior art field. The patent’s claims were ultimately found unpatentable, consistent with the depth of foundational prior art in SMPS circuit design.
Switch-mode power supply patents sit at the intersection of power electronics and semiconductor IP — a space intensely litigated given the ubiquity of the technology in Samsung’s product portfolio across smartphones, displays, and home appliances. A patent asserting a primary-sided active circuit topology could theoretically implicate a wide range of AC/DC and DC/DC converter implementations. The Federal Circuit’s affirmance of unpatentability confirms that the asserted claims could not survive prior art scrutiny, reducing — but not eliminating — uncertainty for competitors relying on similar circuit architectures.
Should your team run an FTO analysis against US7403399B2?
Product teams developing switch-mode power supply circuits, power management ICs, or AC/DC converter modules should note that US7403399B2 has been affirmed as unpatentable by the Federal Circuit. While this specific patent no longer poses an enforcement risk, it is common for patent assertion entities to hold related continuation or divisional applications covering similar circuit topologies. Any team commercialising active primary-sided SMPS architectures should verify whether related applications in MyPaq’s portfolio remain active and potentially enforceable.
PatSnap Eureka’s FTO Search Agent can map the full patent family around US7403399B2, identify related pending applications, and surface prior art that supports design-around or invalidity arguments for related claims. R&D teams can run landscape analyses across the switch-mode power supply domain to identify remaining assertion risk before committing to a circuit topology in production hardware.
Run a freedom-to-operate analysis on US7403399B2 to assess your product’s exposure
Run FTO in Eureka →Similar Federal Circuit appeals in switch-mode power supply patent disputes
Explore Federal Circuit cases involving switch-mode power supply and power electronics patents, including Rule 36 affirmances and PTAB-origin appeals in the semiconductor and consumer electronics sector.
What this case signals for the power supply and electronics IP landscape
A Rule 36 affirmance at the Federal Circuit is a clean, final win for Samsung — and a roadmap signal for how power supply patent assertions are being resolved.
Rule 36 affirmances signal strong underlying invalidity records
When the Federal Circuit issues a Rule 36 judgment, it signals the panel found the lower tribunal’s reasoning unambiguous. For patent holders in the power management sector, this underscores the importance of anticipating prior art depth before asserting switch-mode power supply patents, particularly in inter partes proceedings.
Switch-mode power supply patents face rigorous prior art scrutiny
The switch-mode power supply space is technically mature, with deep prior art from the 1980s onward. Patents asserting active primary-sided topologies are particularly vulnerable to unpatentability challenges. IP teams should audit pending and asserted patents in this space against foundational power electronics literature before committing to enforcement campaigns.
MYPAQ v Samsung — key questions answered
A Rule 36 affirmance means the Federal Circuit reviewed the full record and found no reversible error in the lower tribunal’s unpatentability finding. No written opinion was issued. The practical result is that US7403399B2 is conclusively cancelled, and MyPaq has no further enforcement rights in the adjudicated claims against Samsung or third parties.
US7403399B2 covers an active primary-sided circuit arrangement for a switch-mode power supply — a power conversion topology controlling switching behaviour on the input (primary) side of the transformer. Switch-mode power supplies are widely used in consumer electronics, computing hardware, and telecommunications equipment, making this patent technically relevant to Samsung’s core product lines.
The basis of termination is recorded as ‘Unpatentable’, consistent with a proceeding — likely an inter partes review or similar validity challenge — in which the claims of US7403399B2 were found to fail patentability requirements. The Federal Circuit’s affirmance confirms that finding is final at this appellate level.
Following a Federal Circuit Rule 36 affirmance, the remaining options are a petition for panel rehearing or rehearing en banc, or a petition for writ of certiorari to the United States Supreme Court. Both options face high thresholds and are statistically unlikely to succeed absent a significant legal question of broader applicability. The public record does not indicate any such petition has been filed.
The Rule 36 affirmance creates no binding citable precedent for third parties, but the underlying cancellation of US7403399B2 removes that specific patent as an enforcement risk across the market. Companies commercialising active primary-sided SMPS circuit topologies should nonetheless audit related continuation or divisional applications in MyPaq’s portfolio, as those may cover similar technology with potentially surviving claims.
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