Sonova v. MED-EL: Federal Circuit Affirms Hearing Aid Coating Patent (Case 22-1865)
Sonova AG and MED-EL Elektromedizinische Geräte GmbH clashed before the Federal Circuit over the validity of US7267847B2, protecting hydrophobic coating of individual hearing aid components. A per curiam panel of three judges affirmed the decision below in 371 days, with no written opinion issued.
Federal Circuit ends Sonova–MED-EL patent validity dispute with Rule 36 affirmance
Sonova AG, a Swiss hearing technology company, filed appeal No. 22-1865 at the United States Court of Appeals for the Federal Circuit on 3 June 2022, challenging a ruling concerning the validity of US7267847B2. That patent covers hydrophobic coating applied to individual components of hearing aid devices — a technology relevant to the durability and moisture resistance of hearing instruments. MED-EL Elektromedizinische Geräte GmbH, an Austrian hearing implant manufacturer, was named as the respondent.
On 9 June 2023 — 371 days after the appeal was filed — a three-judge Federal Circuit panel comprising Circuit Judges Dyk, Bryson, and Stark issued a per curiam affirmance under Federal Circuit Rule 36. The recorded Basis of Termination is 'Appeal Dismissed'; the docket order states 'AFFIRMED. See Fed. Cir. R. 36.' The specific terms underlying any related proceedings are not disclosed in the available record.
A Rule 36 affirmance issues without a written opinion, meaning the Federal Circuit found no reversible error warranting explanation but left no published reasoning that practitioners can cite. This outcome is consistent with a case where the panel concluded the lower tribunal's decision was correct on the existing record. What arguments were raised and why they were rejected is not detailed in the public appellate docket.
See Complete Case & Patent Analysis →Filing to Appeal Dismissed in 371 days
371 days from filing to Federal Circuit disposition — typical for a per curiam Rule 36 affirmance
US7267847B2 — Hydrophobic coating of hearing aid device components
Any manufacturer, supplier, or OEM that applies hydrophobic, water-repellent, or moisture-resistant coatings to individual components of hearing aids, cochlear implants, or similar audio health devices should assess their exposure to US7267847B2. The patent has now survived appellate challenge, elevating its litigation risk profile. Component-level coating processes — whether applied in-house or by a contract manufacturer — may fall within its claim scope.
Official order — verbatim text
The per curiam order affirms the decision below under Federal Circuit Rule 36, a procedure reserved for cases where the panel finds no reversible error and no precedential value in a written opinion. The terse 'AFFIRMED' entry means the ruling below — on patentability of the hydrophobic hearing aid coating claims — is upheld in its entirety, but the court's reasoning is not publicly disclosed.
Federal Circuit affirms: what the ruling means for both parties
What a Federal Circuit Rule 36 affirmance means
Under Fed. Cir. R. 36, the court may enter judgment of affirmance without a written opinion when it determines the decision below is correct and that a written opinion would serve no precedential purpose. The lower tribunal's decision stands in full. No new legal standard is established, and the order cannot be cited as precedent by either party in future proceedings.
No reversible error foundMED-EL's position is upheld at the appellate level
Because the Federal Circuit affirmed the decision below, MED-EL — as respondent — retains the benefit of whatever ruling was entered at the tribunal below. The validity challenge brought by Sonova did not succeed on appeal. The patent's enforceability status as determined below is preserved, and MED-EL faces no further appellate exposure at this level from this proceeding.
Respondent position preservedSonova's appellate challenge to US7267847B2 fails
Sonova's appeal is exhausted at the Federal Circuit level. The affirmance under Rule 36 forecloses any further argument that the tribunal below erred. Sonova's remaining options — such as a petition for rehearing or certiorari to the Supreme Court — exist in theory but face a significantly elevated bar following a panel affirmance. No written opinion means no identified legal error to build on.
Appellate options substantially narrowedHydrophobic hearing aid coating IP strengthened by affirmance
For hearing aid and hearing implant manufacturers active in moisture-protection technology, the affirmance signals that US7267847B2 survived a Federal Circuit validity challenge. Companies developing hydrophobic coating solutions for hearing device components should treat this patent as a durable enforceability risk. The absence of a written opinion limits clarity on which claim elements or prior art arguments the court found unpersuasive.
Patent enforceability risk elevatedFull party and counsel information
| Role | Name | Type | Detail |
|---|---|---|---|
| Plaintiff | Sonova, AG | Company | /Search in Eureka ↗ |
| Defendant | MED-EL Elektromedizinische Geräte, GmbH | Company | /Search in Eureka ↗ |
| Plaintiff counsel | Greg Matthew Polins | Attorney | Counsel for Sonova, AGSearch in Eureka ↗ |
| Plaintiff counsel | Marcus Edward Sernel | Attorney | Counsel for Sonova, AGSearch in Eureka ↗ |
| Plaintiff law firm | Kirkland & Ellis, LLP | Law Firm | Representing Sonova, AGSearch in Eureka ↗ |
| Defendant counsel | Kathryn E. Noll | Attorney | Counsel for MED-EL Elektromedizinische Geräte, GmbHSearch in Eureka ↗ |
| Defendant counsel | Lisa M. Tittemore | Attorney | Counsel for MED-EL Elektromedizinische Geräte, GmbHSearch in Eureka ↗ |
| Defendant law firm | Sunstein LLP | Law Firm | Representing MED-EL Elektromedizinische Geräte, GmbHSearch in Eureka ↗ |
| Presiding judge | Judge N/A | Judge | Court of Appeals for the Federal CircuitSearch in Eureka ↗ |
R&D signals in the hearing aid moisture-protection IP space
Forward-looking patent intelligence on hydrophobic coating technology, Sonova's filing activity, MED-EL's IP posture, and white space near US7267847B2.
Sonova's patent activity in hearing device surface protection
Sonova AG has a broad hearing technology portfolio. Tracking their recent filing activity in moisture protection, hydrophobic surface treatment, and component encapsulation for hearing aids can signal where their next enforcement campaign may focus. Continuation and divisional applications near US7267847B2's priority date are particularly worth monitoring.
Sonova filing trendsFiling trends in hydrophobic coating for audio health devices
The broader technology landscape around moisture-resistant coatings for miniaturised electronic and medical audio devices has seen increasing activity as hearing aid form factors shrink. Mapping patent density by assignee, filing year, and IPC class in this domain reveals which players are investing most heavily and where crowding versus white space exists.
Coating IP landscapeMED-EL's own IP in implant durability and surface treatment
MED-EL successfully defended this Federal Circuit appeal. Analysing MED-EL's own patent portfolio in cochlear implant durability, biocompatible coatings, and moisture management for implantable audio devices reveals their defensive IP depth and any offensive assets they may hold in adjacent coating technology domains.
MED-EL IP mappingAdjacent R&D opportunities in selective component-level coating
US7267847B2 focuses on coating applied to individual components rather than whole-device encapsulation. Adjacent white space may exist in novel coating materials, application methods, or substrate-specific formulations not yet claimed — particularly for next-generation miniaturised or implantable hearing devices where existing patents may not extend.
Component coating white spaceSimilar Federal Circuit appeals in hearing aid and medical device patent validity
Explore Federal Circuit patentability appeals involving hearing aid technology, hydrophobic coatings, and medical device component IP similar to Case 22-1865.
What this case signals for the hearing aid IP landscape
A Federal Circuit Rule 36 affirmance in a hearing aid coating patent dispute carries quiet but significant weight for competitors in the space.
Rule 36 affirmances leave competitors without a roadmap for future challenges
Because no written opinion accompanies the affirmance, the arguments Sonova raised — and why they failed — are not part of the public record. Competitors and would-be challengers to US7267847B2 cannot study the reasoning to calibrate a better invalidity strategy. A fresh prior art search and claim mapping exercise is advisable before launching any new challenge.
Hydrophobic coating for hearing aids is a legally tested, enforceable IP space
US7267847B2 has now survived appellate scrutiny in a patentability action. For any company — including component suppliers and OEM hearing device makers — that applies hydrophobic or moisture-resistant coatings to individual hearing aid parts, a freedom-to-operate analysis against this patent is no longer optional. The patent's durability in litigation increases its licensing and enforcement leverage.
Sonova v MED-EL — key questions answered
The Federal Circuit issued a per curiam affirmance under Fed. Cir. R. 36 on 9 June 2023, upholding the decision below in the patentability dispute involving US7267847B2. No written opinion was issued. The recorded Basis of Termination is 'Appeal Dismissed'; the docket order states 'AFFIRMED.'
A Rule 36 affirmance means the three-judge panel found no reversible error in the decision below and that no precedential opinion was warranted. The lower tribunal's ruling on the patent's validity stands. The order cannot be cited as precedent, and no public reasoning is available explaining which arguments failed.
The patent at issue is US7267847B2 (application number US10/749291), which covers hydrophobic coating of individual components of hearing aid devices — a technology addressing moisture intrusion and component durability in hearing instruments.
Sonova AG was represented by Greg Matthew Polins and Marcus Edward Sernel of Kirkland & Ellis, LLP. MED-EL Elektromedizinische Geräte GmbH was represented by Kathryn E. Noll and Lisa M. Tittemore of Sunstein LLP.
Following a Federal Circuit affirmance of the underlying patentability ruling, US7267847B2 presents an elevated enforceability risk for companies applying hydrophobic coatings to individual hearing aid components. An FTO analysis against this patent is advisable for manufacturers, OEMs, and component suppliers in the hearing device sector. The specific terms of the underlying proceeding are not disclosed in the available record.
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