Serendia v. Cynosure: Six-Patent Dermatological Device Dispute Ends in Voluntary Dismissal
Serendia, LLC filed suit against Cynosure, LLC in the Delaware District Court asserting six patents covering electrically based medical treatment and skin care devices. After 656 days of litigation, Serendia voluntarily dismissed the case before Cynosure filed an answer, with each party bearing its own costs.
Six-Patent Dermatology Suit Exits Delaware Before Any Answer Filed
Serendia, LLC initiated this infringement action on 1 March 2023 in the United States District Court for the District of Delaware before Judge Richard G. Andrews. The complaint asserted six patents — US11406444B2, US9775774B2, US10058379B2, US9320536B2, US9480836B2, and US10869812B2 — all directed to electrically based medical treatment devices, dermatological skin treatment apparatus, and related methods. The named defendant, Cynosure, LLC, is a well-known developer of energy-based medical aesthetic devices.
On 16 December 2024, Serendia filed a notice of voluntary dismissal pursuant to Federal Rule of Civil Procedure 41(a)(1)(A)(i), which permits a plaintiff to dismiss an action as of right — without a court order — before the defendant has served an answer or a motion for summary judgment. Cynosure had not yet answered the complaint, satisfying that procedural threshold. The notice specified that each party shall bear its own costs, expenses, and attorneys’ fees, removing any fee-shifting dispute from the record.
The 656-day duration between filing and dismissal is notable: a Rule 41(a)(1)(A)(i) dismissal can occur at any point before an answer, yet this one took nearly two years. That timeline is consistent with extended pre-answer settlement negotiations or licensing discussions, though the public record does not disclose whether any agreement was reached. Whether the dismissal was with or without prejudice — and therefore whether Serendia retains the right to re-file — is not stated in the public notice and remains unknown.
Filing to Voluntary dismissal in 656 days
656 days — longer than the median uncontested dismissal, suggesting pre-answer negotiations
Voluntarily dismissed: what the Rule 41 exit means for both parties
Rule 41(a)(1)(A)(i) allows dismissal as of right before answer
Federal Rule of Civil Procedure 41(a)(1)(A)(i) permits a plaintiff to dismiss an action without a court order by filing a notice of dismissal before the defendant has served an answer or a motion for summary judgment. Because Cynosure had not yet answered, Serendia could exit unilaterally. The court played no substantive role — no merits were adjudicated and no findings were made on infringement or validity.
No merits adjudicatedThe public record is silent on prejudice status
A voluntary dismissal filed before an answer is presumed without prejudice under Rule 41(a)(1)(B) unless the notice itself states otherwise. However, Serendia’s notice does not expressly specify. This distinction matters enormously: a dismissal without prejudice preserves Serendia’s right to re-file the same claims; a dismissal with prejudice permanently bars re-litigation. Practitioners monitoring this case should not assume either outcome — the public filing is silent on this point.
Prejudice status unclearCynosure exits without any merits ruling or validity finding
Because the case was dismissed before Cynosure answered, Cynosure faces no judgment of infringement and no court has assessed the validity of the six asserted patents. Each party bears its own legal costs. Cynosure should remain alert: if the dismissal was without prejudice, Serendia retains the ability to reassert these patents in a future action, subject to any statute of limitations or licensing terms that may have been privately negotiated.
No liability findingSix dermatological device patents remain live enforcement tools
The voluntary dismissal leaves all six asserted patents intact and enforceable. Competitors in the energy-based and electrically based aesthetic device market — including any party whose products touch electrical stimulation, skin treatment apparatus, or dermatological treatment methods — should treat these patents as live risk. The absence of a merits ruling means there is no invalidity finding, no claim construction record, and no prosecution history estoppel from this proceeding to rely on in future disputes.
Patents remain enforceableFull party and counsel information
| Role | Name | Type | Detail |
|---|---|---|---|
| Plaintiff | Serendia, LLC | Company | Medical device IP licensor — holder of US11406444B2 and 5 related dermatological treatment patentsSearch in Eureka ↗ |
| Defendant | Cynosure, LLC | Company | Cynosure, LLC — developer and marketer of energy-based aesthetic and dermatological treatment systemsSearch in Eureka ↗ |
| Plaintiff counsel | Cecilia Sanabria | Attorney | Counsel for Serendia, LLCSearch in Eureka ↗ |
| Plaintiff counsel | Charles H. Sanders | Attorney | Counsel for Serendia, LLCSearch in Eureka ↗ |
| Plaintiff counsel | Kevin C. Wheeler | Attorney | Counsel for Serendia, LLCSearch in Eureka ↗ |
| Plaintiff counsel | Timothy Devlin | Attorney | Counsel for Serendia, LLCSearch in Eureka ↗ |
| Plaintiff law firm | Devlin Law Firm LLC | Law Firm | Representing Serendia, LLCSearch in Eureka ↗ |
| Defendant counsel | Dominick T. Gattuso | Attorney | Counsel for Cynosure, LLCSearch in Eureka ↗ |
| Defendant law firm | Heyman Enerio Gattuso & Hirzel, LLP | Law Firm | Representing Cynosure, LLCSearch in Eureka ↗ |
| Presiding judge | Judge Richard G. Andrews | Judge | Delaware District CourtSearch in Eureka ↗ |
Official order — verbatim text
The dismissal notice invokes Rule 41(a)(1)(A)(i) precisely and confirms the procedural precondition — Cynosure had not yet answered — was met. The phrase ‘each party shall bear its own costs’ is a deliberate mutual cost-neutrality clause, removing any basis for a later fee motion. Notably, the notice is silent on whether the dismissal is with or without prejudice. Under Rule 41(a)(1)(B), a first voluntary dismissal is presumed without prejudice absent an express statement, but practitioners should verify whether any side agreement modifies that default.
US11406444B2 — Electrically Based Dermatological Treatment Devices
The six asserted patents — anchored by US11406444B2 (application US17/061523) and including US9775774B2, US10058379B2, US9320536B2, US9480836B2, and US10869812B2 — collectively cover electrically based medical treatment devices, dermatological skin treatment apparatus, and associated methods. The family spans multiple application generations, suggesting a continuation-heavy prosecution strategy designed to maintain broad claim coverage across evolving product designs in the electrical aesthetic and therapeutic skin treatment domain.
For competitors developing energy-based devices targeting skin conditions — including radiofrequency, microcurrent, electroporation, or electrical stimulation platforms — this six-patent portfolio represents meaningful freedom-to-operate risk. The breadth of the asserted claims across method, system, and apparatus categories means that design-arounds must address all three claim types independently. The fact that Cynosure, a major aesthetic device OEM, was named as defendant underscores that this portfolio is positioned for enforcement against commercial-scale players, not just startups.
Should you run an FTO against US11406444B2 and its related family?
Any company developing or commercialising electrically based skin treatment devices, dermatological apparatus, or energy-delivery medical systems should treat this six-patent family as a priority FTO target. The portfolio’s multi-generational continuation structure means that claims may have been drafted to read on successive product generations — including those launched after the earliest priority dates. OEMs, component suppliers, and software platform providers in the aesthetic device segment all carry potential exposure.
PatSnap Eureka’s FTO Search Agent can map each of the six asserted patents against your product’s technical architecture, flag claim elements most likely to read on current device designs, and surface any post-grant proceedings — IPR petitions, ex parte reexaminations, or certificates of correction — that may affect claim scope. Given that this case closed without a claim construction order, there is no judicial record to rely on: a full independent FTO analysis is the only reliable risk-management step available.
Run a freedom-to-operate analysis on US11406444B2 to assess your product’s exposure
Run FTO in Eureka →Similar Dermatological Device Patent Cases in Delaware District Court
Explore comparable patent infringement actions involving electrically based medical and aesthetic treatment devices litigated in the Delaware District Court.
What this case signals for the medical aesthetic device IP landscape
A six-patent pre-answer exit after nearly two years suggests the dermatological device space carries significant IP pressure that often resolves outside the public record.
Long pre-answer timelines often signal private resolution
A Rule 41(a)(1)(A)(i) dismissal can technically occur on day one. A 656-day gap between filing and dismissal — with no answer ever served — is consistent with extended licensing or settlement negotiations. Companies operating in the electrical aesthetic device space should assume that similar disputes may resolve privately, leaving no public claim construction record.
Six-patent portfolios raise the cost of non-engagement for defendants
Asserting six patents across related dermatological treatment product categories signals a broad enforcement portfolio strategy. Defendants facing multi-patent complaints in Delaware should conduct early claim-mapping across all asserted patents — not just the lead patent — to evaluate invalidity and non-infringement positions before the pre-answer window closes.
Serendia v Cynosure — key questions answered
Serendia asserted six patents: US11406444B2, US9775774B2, US10058379B2, US9320536B2, US9480836B2, and US10869812B2. All cover electrically based medical treatment devices, dermatological skin treatment apparatus, and related methods. The case was filed in the Delaware District Court on 1 March 2023.
Serendia filed a notice of voluntary dismissal under Federal Rule of Civil Procedure 41(a)(1)(A)(i) on 16 December 2024. This rule allows a plaintiff to dismiss without a court order before the defendant has answered. Cynosure had not filed an answer, satisfying the rule’s precondition. No merits were adjudicated. The public record does not state whether the dismissal was with or without prejudice.
Potentially. Under Rule 41(a)(1)(B), a first voluntary dismissal is presumed without prejudice unless the notice states otherwise. Serendia’s notice does not expressly designate prejudice status. If the dismissal is without prejudice, Serendia may re-file subject to any applicable statute of limitations. Any private settlement or licensing agreement may also limit re-filing rights, but no such agreement is disclosed in the public record.
Serendia was represented by Devlin Law Firm LLC, with attorneys Timothy Devlin, Charles H. Sanders, Kevin C. Wheeler, and Cecilia Sanabria listed as counsel. Cynosure was represented by Heyman Enerio Gattuso & Hirzel, LLP, with Dominick T. Gattuso as lead counsel. Judge Richard G. Andrews presided over the case in the District of Delaware.
All six asserted patents remain in force and no invalidity findings were made. Companies in the energy-based aesthetic and dermatological device market — including OEMs and component suppliers — should conduct freedom-to-operate analyses against this portfolio. The long pre-answer timeline suggests private resolution may have occurred, but without public disclosure, competitors cannot assume any licensing or cross-licensing arrangement is in place.
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