CALDERWOOD & HARKNESS LLP 600 Lexington Avenue, 22nd Floor New York, NY 10022 Tel: (212) 554-7200
PRIVILEGED & CONFIDENTIAL — ATTORNEY-CLIENT COMMUNICATION
MEMORANDUM
November 18, 2024
To: Ronan Gallagher, General Counsel & Company Secretary, Solstice Biomedical Devices Ltd.
From: Alan Ngo, Responsible Partner — Intellectual Property (USPTO Reg. No. 58,412)
Re: CryoNova Patent Family — Portfolio Strategy and Go-Forward Recommendation
Matter No.: SBD-IP-2021-003
Copies to: Dr. Fiona Tierney, CEO & Co-Founder, Solstice Biomedical Devices Ltd.; Marcus Delgado, Billing Partner, Calderwood & Harkness LLP
I. Executive Summary
This memorandum responds to your email of October 28, 2024, in which you requested a comprehensive portfolio review and go-forward recommendation for the CryoNova cryoablation catheter patent family. You asked that our analysis be completed in advance of the year-end board meeting so that the board of directors of Solstice Biomedical Devices Ltd. ("SBD") may make an informed decision regarding the future of the CryoNova intellectual property assets. We appreciate the opportunity to provide this analysis and have endeavored to present it in a form that is suitable for direct circulation to the board.
As you are aware, the CryoNova product program was shelved by SBD's board on June 8, 2023, following the failure of the FROST-AF pivotal clinical trial (IDE No. G210047), which did not meet its primary efficacy endpoint. Since that time, the U.S. patent prosecution docket managed by Calderwood & Harkness LLP ("C&H") has been dormant. The last prosecution activity on the docket occurred on July 3, 2023, when our lead associate, Peter Vassiliev, filed a two-month extension of time in one of the pending continuation applications. No further instructions were received from SBD until your October 28, 2024 inquiry.
The CryoNova patent family currently comprises one issued U.S. patent — U.S. Patent No. 11,284,561 (the "Parent Patent") — and three continuation applications pending before the United States Patent and Trademark Office ("USPTO"): CON-1 (U.S. Application No. 17/702,489), CON-2 (U.S. Application No. 17/851,216), and CON-3 (U.S. Application No. 18/109,744). Of these, CON-1 has been deemed abandoned following a failure to pay the issue fee, CON-2 has received a Non-Final Office Action requiring a substantive response, and CON-3 remains pending but has not yet received a first Office Action from the USPTO.
The most urgent deadline confronting the portfolio is the response deadline in CON-2. Examiner James R. Dougherty of Art Unit 3794 mailed a Non-Final Office Action on September 15, 2024. The statutory three-month response period expires on January 15, 2025. This deadline may be extended by up to three additional months (to April 15, 2025) upon payment of extension-of-time fees totaling $1,380 at the small-entity rate. We strongly recommend filing for the maximum extension immediately, regardless of which strategic scenario the board ultimately selects, in order to preserve all options.
In this memorandum, we analyze three scenarios for the board's consideration:
Scenario 1 — Maintain Full Portfolio: Continue prosecution of all pending applications, revive the abandoned CON-1, and maintain the issued Parent Patent. Estimated near-term cost: $26,470–$34,970.
Scenario 2 — Selective Prosecution (Recommended): Maintain the issued Parent Patent and pursue allowance of CON-2, while abandoning CON-1 and CON-3. Estimated near-term cost: $20,380–$27,380.
Scenario 3 — Full Abandonment: Take no further prosecution action and allow all patent rights to lapse. Cost: $0.
We recommend Scenario 2 — Selective Prosecution — as the optimal go-forward strategy. This approach preserves the most commercially valuable intellectual property assets at a moderate cost, maintains a credible licensing package for potential discussions with industry participants such as Helios Surgical Technologies, Inc. and Vantage Cryosurgical Systems, Inc., and avoids the costs and uncertainties associated with reviving CON-1 and prosecuting CON-3. The near-term expenditure of $20,380–$27,380 is manageable relative to SBD's €74.3 million annual revenue and is supported by the expressed interest of Pinnacle Health Ventures in preserving the CryoNova IP for potential out-licensing.
Several immediate action items require board authorization. These are summarized in Section IX of this memorandum and are keyed to specific deadlines. We request that written instructions be provided to our firm no later than December 31, 2024, to allow adequate time for prosecution preparation.
II. Background
A. Solstice Biomedical Devices Ltd. — Company Overview
Solstice Biomedical Devices Ltd. ("SBD") is an Irish-headquartered private limited company registered with the Companies Registration Office under CRO No. 647832. The company's registered office is located at Unit 4, Liffey Innovation Campus, Parkgate Street, Dublin 8, D08 XR29, Ireland. SBD operates in the United States through its wholly owned subsidiary, Solstice Biomedical Inc., a Delaware corporation (DE File No. 7291456), with offices at 200 Chestnut Ridge Road, Suite 310, Woodcliff Lake, New Jersey 07677.
SBD specializes in cardiac cryoablation and electrophysiology mapping technologies. The company's product portfolio encompasses several device platforms in varying stages of development and commercialization, though the CryoNova cryoablation catheter — the subject of this memorandum — was pre-commercial at the time the program was shelved. For the fiscal year ended December 31, 2023, SBD reported annual revenue of approximately €74.3 million, generated entirely from its other commercial product lines. As of the same date, SBD employed 312 individuals globally across its Irish, U.S., and European operations.
The company's board of directors comprises five members. SBD's majority investors are Pinnacle Health Ventures, which served as the lead investor in SBD's Series B financing round and holds approximately 34% of the company's equity, and Cloverfield Partners, which led the Series A round and holds approximately 22% equity. The company's auditor is Hargrove & Pallister LLP, based in Dublin, and its primary lending relationship is with Meridian Capital Bank plc, also based in Dublin. Dr. Fiona Tierney serves as CEO and Co-Founder, and Ronan Gallagher serves as General Counsel and Company Secretary.
B. CryoNova Product Program History
The CryoNova catheter represented SBD's second-generation cryoablation platform, designed for pulmonary-vein isolation ("PVI") in the treatment of atrial fibrillation ("AF"). The CryoNova system's key technological differentiator was its variable-zone cooling capability with integrated impedance mapping, which allowed clinicians to selectively control the cooling zone along the catheter body while simultaneously monitoring tissue impedance in real time. This architecture was distinct from the single-zone balloon designs employed by competitors, most notably Vantage Cryosurgical Systems, Inc. ("Vantage"), whose cryoablation products utilize a fundamentally different approach to lesion delivery.
The CryoNova program progressed through several key development milestones. SBD completed bench testing validating the variable-zone cooling mechanism and the integration of impedance mapping electrodes into the catheter platform. The company subsequently completed a first-in-human clinical study conducted in Europe (n=15 patients), which demonstrated technical feasibility and an acceptable safety profile.
On the basis of these results, SBD initiated the FROST-AF pivotal trial under an Investigational Device Exemption ("IDE") approved by the U.S. Food and Drug Administration (IDE No. G210047). The FROST-AF trial was a prospective, randomized, multi-center study designed to evaluate the safety and efficacy of the CryoNova catheter for PVI in patients with drug-refractory paroxysmal atrial fibrillation. The trial enrolled 220 patients across clinical sites in the United States.
On May 17, 2023, SBD announced that the FROST-AF trial had failed to meet its primary efficacy endpoint. Specifically, the primary endpoint — freedom from atrial arrhythmia at 12 months following the index procedure — was observed in 58.2% of CryoNova-treated patients, falling short of the pre-specified performance goal of 65% (p = 0.14). The difference was not statistically significant, and the trial was deemed to have failed to demonstrate the clinical efficacy necessary to support a premarket approval ("PMA") application.
Following the announcement of the FROST-AF trial results, the SBD board of directors convened a special meeting on June 8, 2023, at which the board voted to shelve the CryoNova product program indefinitely. The board's decision was driven by the clinical trial outcome and the projected costs of redesigning the catheter or conducting an additional pivotal trial. As a consequence of the program being shelved, the CryoNova development team was reassigned to other projects within SBD, and prosecution of the CryoNova patent family was effectively paused.
The named inventors on the CryoNova patent applications are as follows:
• Dr. Aisling Connolly, Vice President of Research & Development at SBD and co-inventor on all four applications in the family (Parent, CON-1, CON-2, and CON-3);
• Dr. Tomás Brennan, Chief Medical Officer and Co-Founder of SBD, and co-inventor on all four applications in the family; and
• Dr. Henrik Paulsen, former Senior Engineer at SBD, co-inventor on the Parent Patent and CON-1 only. Dr. Paulsen departed SBD in July 2022 and subsequently joined Arclight Therapeutics GmbH. His inventorship obligations and assignment of patent rights to SBD were confirmed prior to his departure, and his cooperation is not required for any pending prosecution actions.
C. Engagement History
Calderwood & Harkness LLP was engaged by SBD on October 5, 2021, pursuant to an engagement letter of the same date, to prosecute the CryoNova cryoablation catheter patent family before the USPTO. The engagement is governed by Delaware law, as specified in the engagement letter.
The C&H team assigned to the CryoNova matter comprises the following professionals:
• Alan Ngo, Responsible Partner (USPTO Reg. No. 58,412);
• Marcus Delgado, Billing Partner;
• Peter Vassiliev, Lead Associate (USPTO Reg. No. 72,340);
• Wendy Schultz, Working Associate (USPTO Reg. No. 78,115); and
• Dr. Claire Nakamura, Patent Agent and Technical Specialist (USPTO Reg. No. 66,203).
In connection with the prosecution of the CryoNova family, C&H retained Caravel Prior Art Services LLC ("Caravel") to conduct prior-art searches. The principal contact at Caravel is Daniel Yoon, Senior Search Analyst. Caravel's search work was conducted under C&H's direction and is subject to attorney-client privilege and work-product protection.
It is important to note that certain foreign filings corresponding to the CryoNova patent family are prosecuted by separate counsel and are outside the scope of C&H's engagement. Specifically, the corresponding European patent application (EP Application No. 21 741 632.8) and the underlying PCT application (PCT/EP2021/067891, filed June 28, 2021) are handled by Dunmore & Firth Patent Attorneys, with Siobhán Firth serving as the responsible partner. The Japanese national phase application (JP Application No. 2023-500714) is handled by Takeda & Morioka Patent Office. While these foreign filings are relevant to the overall portfolio valuation and are referenced in Section III.C below, C&H does not provide advice or take action with respect to those applications.
From the inception of the engagement in October 2021 through the last prosecution activity in July 2023, C&H billed a total of $287,450 to SBD for work on the CryoNova patent family. This total comprises:
• Professional fees: $214,600
• USPTO government fees: $38,350
• Caravel Prior Art Services LLC search fees: $22,500
• Miscellaneous disbursements (filing, copying, courier, etc.): $12,000
All invoices rendered through July 2023 have been paid in full, and there is no outstanding accounts receivable balance on this matter. The last billable activity on the docket occurred on July 3, 2023, when Peter Vassiliev filed a two-month extension of time in the CON-2 application. The docket has been dormant since that date, and no further work has been performed until the preparation of this memorandum at your request.
III. Current Patent Family Status
A. Summary Status Table
The following table summarizes the current status of each application and patent in the CryoNova patent family as of the date of this memorandum:
Each of these applications and the issued patent is discussed in greater detail below and in subsequent sections of this memorandum.
SBD-001 (Parent Patent). U.S. Patent No. 11,284,561 issued on March 22, 2022, with 24 claims directed to the CryoNova cryoablation catheter system with variable-zone cooling. The patent is currently in force and will remain in force provided maintenance fees are timely paid. The next maintenance fee — the 3.5-year fee of $1,000 at the small-entity rate — is due on September 22, 2025. This patent provides the foundational apparatus claims for the CryoNova technology and serves as the priority document for all three continuation applications.
SBD-001-CON1 (Continuation 1). This application was filed on March 23, 2022, as a continuation of the Parent Patent and is directed to method claims for performing cryoablation using the variable-zone cooling catheter. CON-1 received a Notice of Allowance with an Examiner's Amendment on April 10, 2023. The small-entity issue fee of $540 was due by July 10, 2023. Due to an internal docketing lapse at SBD — which occurred when the CryoNova team was reassigned following the board's June 8, 2023 decision to shelve the program — the issue fee was not paid. The application was deemed abandoned as of July 11, 2023. SBD has confirmed to us that the non-payment was unintentional and was solely the result of the administrative disruption caused by the program shelving. This application is potentially revivable, as discussed in Section V below.
SBD-001-CON2 (Continuation 2). This application was filed on June 27, 2022, and is directed to the cryoablation catheter with integrated impedance mapping electrodes. CON-2 is the most actively pending application in the family and is the subject of the Non-Final Office Action discussed in detail in Section IV below. The application has 20 claims pending before Examiner James R. Dougherty of Art Unit 3794 (Surgical Instruments — Cryotherapy). The response deadline is January 15, 2025, with extensions available to April 15, 2025.
SBD-001-CON3 (Continuation 3). This application was filed on February 14, 2023, and is directed to the control unit and algorithm for multi-zone cryoablation delivery. CON-3 has not yet received a first Office Action from the USPTO. No examiner has been assigned to the application, and no substantive prosecution action has occurred. There is no current deadline associated with this application, although once a first Office Action is mailed, SBD will face a new response deadline.
B. Entity-Size Status
SBD qualifies as a "small entity" for purposes of USPTO fee calculations under 37 C.F.R. § 1.27. The qualifying criteria are as follows: SBD, including its subsidiaries, employs fewer than 500 individuals (312 global employees as of December 31, 2023), and SBD has not conveyed or is not obligated to convey any rights in the CryoNova patent family to any entity that would not itself qualify as a small entity. SBD does not qualify as a "micro entity" under 37 C.F.R. § 1.29, as its gross income exceeds the applicable threshold for micro-entity status.
All government fees referenced throughout this memorandum are stated at the small-entity rate unless otherwise indicated. We note that SBD's entity-size status should be reconfirmed if there is any material change in the company's employee count, revenue, or licensing arrangements prior to fee payment.
C. Foreign Filing Cross-References
As noted in Section II.C above, the CryoNova patent family includes corresponding foreign filings that are prosecuted by separate counsel and are outside the scope of C&H's engagement. For completeness and to assist in the board's overall portfolio valuation, we identify the following:
• European Patent Application No. 21 741 632.8: This application entered the European regional phase in January 2023 and is being prosecuted by Dunmore & Firth Patent Attorneys (responsible attorney: Siobhán Firth). We understand that the European application is pending before the European Patent Office, although we have not reviewed its prosecution status.
• Japanese Patent Application No. 2023-500714: This application entered the national phase in Japan and is being prosecuted by Takeda & Morioka Patent Office. We similarly have not reviewed its prosecution status.
• PCT Application No. PCT/EP2021/067891: This international application was filed on June 28, 2021, and has now transitioned into the national and regional phases identified above. The PCT application itself is no longer pending.
While C&H does not advise on or take action with respect to these foreign filings, they are relevant to the board's assessment of the overall CryoNova IP portfolio. If the board selects a go-forward scenario that involves abandonment of one or more U.S. applications, the board should separately consider the implications for the corresponding foreign filings and instruct foreign counsel accordingly. We address this point further in Section IX (Action Item 6) below.
IV. Outstanding Office Action — CON-2 (U.S. 17/851,216)
A. Summary of Examiner's Rejections
On September 15, 2024, Examiner James R. Dougherty of Art Unit 3794 (Surgical Instruments — Cryotherapy) mailed a Non-Final Office Action in CON-2 (U.S. Application No. 17/851,216). The supervisory patent examiner for Art Unit 3794 is Linda M. Kowalski. The Office Action addresses all 20 pending claims and raises three grounds of rejection or objection, which we summarize as follows:
1. Claims 1–8 — Rejection under 35 U.S.C. § 103 (Obviousness). Independent Claim 1 and dependent Claims 2–8 are rejected as being unpatentable under 35 U.S.C. § 103 as obvious over a combination of three prior-art references:
• U.S. Patent No. 10,537,418 (assigned to Vantage Cryosurgical Systems, Inc.), which discloses a single-zone cryoablation balloon catheter system;
• U.S. Patent No. 9,861,432 (also assigned to Vantage Cryosurgical Systems, Inc.), which discloses cryogenic fluid delivery mechanisms for ablation catheters; and
• U.S. Publication No. 2019/0183567 (assigned to Helios Surgical Technologies, Inc.), which discloses impedance-based tissue contact monitoring in electrophysiology catheters.
The Examiner takes the position that it would have been obvious to one of ordinary skill in the art to combine the cryoablation catheter teachings of the two Vantage references with the impedance monitoring teachings of the Helios reference to arrive at the claimed cryoablation catheter with integrated impedance mapping electrodes. The Examiner provides a detailed claim-by-claim mapping in the Office Action, which is attached as Appendix B.
2. Claims 9–14 — Rejection under 35 U.S.C. § 112(a) (Written Description). Claims 9–14, which are directed to specific aspects of the impedance mapping calibration algorithm used in conjunction with the catheter, are rejected under 35 U.S.C. § 112(a) for alleged lack of written description support. The Examiner asserts that the specification does not provide sufficient detail regarding the calibration algorithm to demonstrate that the inventors had possession of the claimed subject matter at the time of filing. Specifically, the Examiner identifies what he characterizes as gaps in the description of the algorithmic steps for normalizing impedance values across multiple cooling zones and adjusting calibration parameters in real time based on tissue contact force feedback.
3. Claims 15–20 — Objection (Allowable Subject Matter). Claims 15–20, which depend from rejected Claim 1, are objected to as depending from a rejected base claim. However, the Examiner has affirmatively indicated that Claims 15–20 contain allowable subject matter that would be allowable if rewritten in independent form including all of the limitations of the base claim and any intervening claims. This is a significant and favorable indication, as it confirms that the specific limitations recited in Claims 15–20 distinguish over the cited prior art.
A complete copy of the Non-Final Office Action is attached as Appendix B for the board's reference.
B. Preliminary Assessment of Overcoming Rejections
Our team has conducted a preliminary analysis of each rejection ground and believes there are good prospects for overcoming all rejections through a combination of claim amendments and supporting arguments. A more detailed prior-art analysis memorandum is being prepared separately by Dr. Claire Nakamura and will be available for client review in connection with the preparation of the Office Action response. Our preliminary assessment is as follows:
Section 103 Rejection (Claims 1–8). The Examiner's obviousness rejection relies on combining three references — two from Vantage and one from Helios — to reach the claimed integration of impedance mapping electrodes with a multi-zone cryoablation catheter. We believe this combination is vulnerable to challenge on multiple grounds. First, the Vantage references disclose only single-zone balloon cryoablation systems, which are architecturally distinct from SBD's variable-zone cooling design. The Vantage system delivers a uniform cooling zone across the entire balloon surface, whereas SBD's claimed invention provides selectively controllable cooling zones along the catheter body. Second, the Helios reference discloses impedance monitoring in the context of radiofrequency ("RF") electrophysiology catheters, not cryoablation catheters, and the integration challenges differ materially between these two modalities. Third, and most importantly, none of the cited references — individually or in combination — teaches or suggests the specific integration of multi-zone cooling control with real-time impedance feedback as recited in the independent claim. The combination requires selective modification of the Vantage balloon architecture to incorporate variable cooling zones (not taught) and simultaneous integration of Helios-type impedance sensing (designed for an entirely different ablation modality) into that modified architecture.
We propose to amend independent Claim 1 to incorporate distinguishing limitations drawn from the dependent claims and the specification, particularly limitations directed to the variable-zone cooling control mechanism and the real-time impedance feedback loop. These amendments would narrow the claim scope while preserving commercially meaningful coverage of the core CryoNova technology. We will also present arguments in the response addressing the lack of motivation to combine the cited references and the teaching-away present in the Vantage prior art (which is oriented toward single-zone balloon simplicity as a design goal).
Section 112(a) Rejection (Claims 9–14). The Examiner's written-description rejection asserts insufficient disclosure of the impedance mapping calibration algorithm. We believe this rejection can be overcome. The impedance mapping calibration algorithm is disclosed in considerable detail in the parent specification (U.S. Patent No. 11,284,561), which is incorporated by reference in the CON-2 application. Specific passages in the parent specification describe the algorithmic steps for impedance normalization, including the multi-zone calibration methodology and the real-time adjustment parameters. These passages were relied upon by the examiner who allowed the parent patent without raising a Section 112(a) issue.
We propose to address this rejection by (i) citing the specific passages from the specification that provide written-description support for each element of Claims 9–14, (ii) providing annotated figures from the specification that illustrate the calibration algorithm workflow, and (iii) supplementing our response with a declaration under 37 C.F.R. § 1.132 ("Rule 132 Declaration") from Dr. Aisling Connolly, VP R&D and named inventor on CON-2. The Connolly Declaration would attest that one of ordinary skill in the art, reading the specification as of the filing date, would understand the disclosed calibration algorithm with sufficient specificity to confirm the inventors' possession of the claimed subject matter. Rule 132 declarations of this type are commonly relied upon by the USPTO to overcome Section 112(a) rejections, particularly in cases involving algorithmic or software-related subject matter where the specification discloses the algorithm in functional terms rather than pseudocode.
Claims 15–20 (Allowable Subject Matter). The Examiner's indication that Claims 15–20 contain allowable subject matter is a positive development. We propose to rewrite Claims 15–20 in independent form, incorporating all limitations of the base claim and any intervening claims, as the Examiner has invited. This would expedite allowance of at least six claims directed to the most novel aspects of the impedance-integrated cryoablation catheter. In combination with the amended Claims 1–8 (if the Section 103 rejection is overcome) and Claims 9–14 (if the Section 112(a) rejection is overcome), this would result in a robust issued patent with broad coverage of the impedance mapping integration technology.
Overall Assessment. Based on our preliminary analysis, we believe there is a reasonable likelihood of obtaining allowance of a meaningful subset of claims in CON-2, and a good possibility of obtaining allowance of all 20 claims (as amended). The path to allowance is clearest for Claims 15–20, which already contain allowable subject matter. Claims 1–8 present a more substantive prosecution challenge, but the distinctions between SBD's variable-zone technology and the cited single-zone balloon prior art are genuine and should be persuasive. Claims 9–14 present a written-description issue that is typically resolvable with a well-crafted declaration and detailed specification citations.
C. Deadline and Extension Options
The statutory three-month response period for the Non-Final Office Action expires on January 15, 2025. Under 37 C.F.R. § 1.136(a), the response deadline may be extended by up to three additional months, for a maximum deadline of April 15, 2025. The extension-of-time fees at the small-entity rate are as follows:
• First month extension (to February 15, 2025): $230
• Second month extension (to March 15, 2025): $460
• Third month extension (to April 15, 2025): $690
• Total for maximum extension: $1,380
Extensions under Section 1.136(a) are available as of right and do not require a showing of cause. The extension fees are cumulative; filing a three-month extension requires payment of all three fees ($230 + $460 + $690 = $1,380).
C&H strongly recommends that the three-month extension be filed immediately upon receipt of board instructions, regardless of which scenario the board ultimately selects. Filing the extension is a precautionary measure that preserves maximum flexibility for SBD. Even if the board selects Scenario 3 (Full Abandonment), the extension filing would be an inexpensive insurance policy that keeps all options open in case circumstances change before the extended deadline. Wendy Schultz has already prepared a draft extension request, and it is ready for filing upon client authorization.
V. CON-1 Revival Analysis
CON-1 (U.S. Application No. 17/702,489), titled "Methods of Cryoablation Using Variable-Zone Cooling Catheter," received a Notice of Allowance with Examiner's Amendment on April 10, 2023. A copy of the Notice of Allowance is attached as Appendix C. The small-entity issue fee of $540 was due on July 10, 2023. The fee was not paid, and the application was deemed abandoned as of July 11, 2023.
Cause of Abandonment. The failure to pay the issue fee was the result of an internal docketing lapse at SBD. When the SBD board voted on June 8, 2023, to shelve the CryoNova program, the CryoNova development team — including individuals responsible for coordinating with outside patent counsel — was reassigned to other projects. In the course of this organizational transition, the July 10, 2023 issue-fee deadline was not communicated to C&H, and no instructions were received from SBD regarding whether to pay or not pay the fee. SBD has confirmed to us that the non-payment was unintentional and that the company did not make a deliberate decision to abandon the application.
Availability of Revival. Under 37 C.F.R. § 1.137(a), a petition to revive an application that became abandoned due to unintentional delay may be filed at any time — there is no statutory time limit. However, the USPTO's practice guidance counsels that the petition should be filed promptly, and extended delays between the date of abandonment and the filing of the petition may invite additional scrutiny. As of the date of this memorandum, the delay has been approximately 16 months (from July 11, 2023 to November 18, 2024). While this is not an unusually long period for an unintentional-delay petition, we recommend that if the board elects to revive CON-1, the petition be filed without unnecessary further delay.
Requirements for Revival. A petition to revive under Section 1.137(a) requires the following:
1. A petition statement, signed by an authorized representative of the applicant, attesting that the entire delay in paying the issue fee was unintentional;
2. Payment of the petition fee of $1,050 (small entity); and
3. Payment of the issue fee of $540 (small entity), together with any other required fees that were not timely paid.
The total government fees for revival are thus $1,590 ($1,050 + $540). C&H's estimated professional fees for preparing and filing the petition, including drafting the petition statement and compiling the necessary documentation, are $4,500–$6,000. The total cost of reviving CON-1 is therefore estimated at $6,090–$7,590.
Inventorship Considerations. CON-1 names three inventors: Dr. Aisling Connolly, Dr. Tomás Brennan, and Dr. Henrik Paulsen. Dr. Paulsen departed SBD in July 2022 and is now employed by Arclight Therapeutics GmbH. We have confirmed that Dr. Paulsen executed a valid assignment of his rights in the CON-1 application to SBD prior to his departure. No cooperation from Dr. Paulsen is required for the filing of a revival petition, as the petition is filed by the applicant (SBD, as assignee) and does not require inventor signatures.
Strategic Value Assessment. CON-1's allowed claims are directed to methods of performing cryoablation using a variable-zone cooling catheter. While method claims provide enforcement leverage — particularly in the context of direct infringement by clinicians using the device and induced infringement by the device manufacturer — the incremental strategic value of CON-1 over the existing portfolio is moderate. The Parent Patent (U.S. Patent No. 11,284,561) already includes 24 claims, several of which contain method-of-use elements that overlap significantly with CON-1's method claims. CON-1's claims do not cover the impedance mapping integration technology, which is the most commercially differentiating aspect of the CryoNova platform and is the subject of CON-2.
In our assessment, the method claims in CON-1 would add incremental enforcement leverage but do not possess substantial independent licensing value separate from the Parent Patent. The cost of revival ($6,090–$7,590) is meaningful relative to the incremental value obtained. Accordingly, we do not recommend revival of CON-1 under our recommended Scenario 2 (Selective Prosecution), though we recognize that the board may reach a different conclusion depending on its assessment of the licensing landscape.
VI. Scenario Analysis
A. Scenario 1: Maintain Full Portfolio
Description. Under Scenario 1, SBD would take all steps necessary to maintain and prosecute the entire CryoNova patent family, including:
• Responding to the Non-Final Office Action in CON-2 (U.S. 17/851,216), including amending claims, traversing the Section 103 and Section 112(a) rejections, and preparing a Rule 132 Declaration from Dr. Aisling Connolly;
• Filing a petition to revive CON-1 (U.S. 17/702,489) under 37 C.F.R. § 1.137(a), paying the petition fee and the issue fee, and bringing the allowed method claims to issuance;
• Continuing to prosecute CON-3 (U.S. 18/109,744) when the first Office Action issues, including preparing and filing a response to whatever rejections or objections the examiner may raise;
• Paying the 3.5-year maintenance fee of $1,000 (small entity) for the issued Parent Patent (U.S. Patent No. 11,284,561) on or before the September 22, 2025 due date; and
• Maintaining all issued patents and pending applications on an ongoing basis, including payment of future maintenance fees and responses to any further Office Actions.
Cost Estimate. The estimated near-term costs for Scenario 1 are as follows:
• CON-2 Office Action response (C&H professional fees): $18,000–$25,000
• CON-2 extension-of-time fees (USPTO): $1,380
• CON-1 revival (C&H professional fees): $4,500–$6,000
• CON-1 revival (USPTO government fees — petition + issue fee): $1,590
• Parent Patent 3.5-year maintenance fee (due September 22, 2025): $1,000
• Total estimated near-term cost: $26,470–$34,970
In addition to the near-term costs identified above, Scenario 1 would entail future costs that are not yet fully estimable, including:
• CON-3 prosecution: When the first Office Action issues in CON-3, SBD will need to prepare and file a substantive response. Based on the complexity of the application and the typical prosecution trajectory in Art Unit 3794, we estimate the cost of responding to a first Office Action in CON-3 at $15,000–$25,000 in professional fees, plus any applicable extension-of-time fees and government fees. Additional costs may be incurred if the examiner issues a Final Office Action requiring further responses, an appeal, or a request for continued examination ("RCE").
• Ongoing maintenance fees for the Parent Patent: The 7.5-year maintenance fee of $1,880 (small entity) will be due in March 2030, and the 11.5-year maintenance fee of $3,880 (small entity) will be due in March 2034.
• Post-issuance maintenance fees for CON-1 and CON-2 (and CON-3, if issued): Each issued patent will require maintenance fee payments at the 3.5-year, 7.5-year, and 11.5-year intervals.
Strategic Considerations. Scenario 1 preserves maximum optionality for SBD with respect to the CryoNova intellectual property. By maintaining the full portfolio — including apparatus claims (Parent), method claims (CON-1), impedance mapping device claims (CON-2), and control-unit/algorithm claims (CON-3) — SBD would retain the broadest possible claim coverage. This breadth of coverage would be advantageous in several contexts:
• Licensing and sale. A comprehensive patent portfolio commands a higher price in licensing negotiations or an outright asset sale. Potential licensees or acquirers, including Helios Surgical Technologies, Inc. and Vantage Cryosurgical Systems, Inc. — both of whom have been flagged by Pinnacle Health Ventures as potential counterparties — would be confronted with a broader scope of patent rights.
• Future commercialization. If SBD or a successor entity were to restart the CryoNova program or develop a next-generation cryoablation catheter incorporating the CryoNova technology, a full portfolio would provide the most comprehensive intellectual property protection for the new product.
• Defensive posture. A full portfolio provides the most robust defensive position in the event of patent litigation initiated by competitors, as it offers the greatest number of claims available for assertion in counterclaims or cross-licensing negotiations.
However, Scenario 1 also carries the highest cost and the most significant ongoing prosecution commitment. The CON-3 prosecution outcome is particularly uncertain, as no prior-art search has yet been conducted on CON-3's specific claims directed to the control unit and algorithm. Furthermore, algorithm-related claims in CON-3 may face patentability challenges under 35 U.S.C. § 101 (patent-eligible subject matter) in light of the Supreme Court's decision in Alice Corp. v. CLS Bank International, 573 U.S. 208 (2014), and its progeny. The costs of overcoming a Section 101 rejection, which may require multiple rounds of prosecution and potentially an appeal to the Patent Trial and Appeal Board, could be substantial and are difficult to estimate at this stage.
Assessment. Scenario 1 is justified only if SBD, or a potential licensee or acquirer, has a credible path to commercializing the CryoNova technology or a next-generation product derived from it, or if the board determines that the full breadth of the patent portfolio is necessary to support a licensing transaction at the price point contemplated by the board and its investors. In the absence of such a clear commercial pathway, the incremental costs and uncertainties associated with reviving CON-1 and prosecuting CON-3 outweigh the marginal strategic benefits relative to Scenario 2.
B. Scenario 2: Selective Prosecution (Recommended)
Description. Under Scenario 2, SBD would take a targeted approach to preserve the most commercially valuable elements of the CryoNova patent family while eliminating costs associated with lower-value assets. Specifically:
• Maintain the issued Parent Patent (U.S. Patent No. 11,284,561): Pay the 3.5-year maintenance fee of $1,000 (small entity) on or before the September 22, 2025 due date. The Parent Patent's 24 apparatus claims provide foundational coverage of the CryoNova variable-zone cooling technology.
• Respond to the CON-2 Office Action (U.S. 17/851,216): Pursue allowance of the impedance mapping claims by amending the claims, traversing the Section 103 and Section 112(a) rejections, and preparing a Rule 132 Declaration from Dr. Aisling Connolly. The goal is to obtain an issued patent with claims covering the integration of impedance mapping electrodes with the cryoablation catheter platform.
• Abandon CON-1 (U.S. 17/702,489): Do not file a petition to revive. The allowed method claims will not issue, and the application will remain abandoned. The method claims are substantially duplicative of method-of-use elements already present in the Parent Patent's 24 claims.
• Abandon CON-3 (U.S. 18/109,744): Either expressly abandon the application by filing a notice of abandonment with the USPTO or allow the application to go abandoned by failing to respond to the first Office Action when it issues. The control-unit/algorithm claims face uncertain patentability and speculative prosecution costs, and the impedance mapping calibration algorithm is partially captured in CON-2's Claims 9–14.
Cost Estimate. The estimated near-term costs for Scenario 2 are as follows:
• CON-2 Office Action response (C&H professional fees): $18,000–$25,000
• CON-2 extension-of-time fees (USPTO): $1,380
• Parent Patent 3.5-year maintenance fee (due September 22, 2025): $1,000
• Total estimated near-term cost: $20,380–$27,380
The savings relative to Scenario 1 are approximately $6,090–$7,590 in near-term costs, reflecting the elimination of CON-1 revival costs ($4,500–$6,000 in professional fees and $1,590 in government fees). Additional savings will accrue over time from the avoidance of CON-3 prosecution costs, which we estimate at $15,000–$25,000 per Office Action response.
Future ongoing costs under Scenario 2 would include the Parent Patent maintenance fees at the 7.5-year interval ($1,880, due March 2030) and the 11.5-year interval ($3,880, due March 2034), as well as maintenance fees for CON-2 upon issuance.
Strategic Considerations — Why CON-2 Has Independent Licensing Value
The core strategic rationale for Scenario 2 rests on the independent licensing value of CON-2's impedance mapping claims. Unlike the Parent Patent's apparatus claims (which are specific to the CryoNova catheter design) and CON-1's method claims (which describe procedures for using the CryoNova catheter), CON-2's claims are directed to the integration of impedance mapping electrodes with a cryoablation catheter platform. This integration concept is a technology differentiator that is applicable beyond the specific CryoNova product to any cryoablation platform that seeks to incorporate real-time impedance feedback for tissue contact assessment and lesion monitoring.
The integration of impedance mapping with ablation catheters is an industry trend that extends across multiple ablation modalities, including radiofrequency, cryoablation, and pulsed-field ablation. As the electrophysiology device market continues to evolve toward catheter systems with integrated sensing and mapping capabilities, the impedance mapping integration claims in CON-2 are likely to have value even if SBD does not itself commercialize the CryoNova catheter. The claims would be relevant to any competitor developing a cryoablation catheter with integrated impedance sensing, and the claims' scope — assuming successful prosecution — would encompass the core integration architecture without being limited to the specific variable-zone cooling design of the CryoNova system.
The Examiner's indication that Claims 15–20 contain allowable subject matter is a significant positive signal. It confirms that the specific claim limitations directed to the impedance mapping integration features distinguish over the cited prior art, and it provides a clear path to obtaining at least six allowed claims in CON-2. If the Section 103 and Section 112(a) rejections are also overcome, the resulting patent could issue with up to 20 claims, providing substantial coverage of the impedance mapping integration technology.
The combination of the issued Parent Patent (apparatus claims) and an issued CON-2 patent (impedance mapping device claims) would provide meaningful leverage for out-licensing discussions. The Parent Patent demonstrates SBD's inventorship of the underlying variable-zone cooling platform, while CON-2 covers the commercially differentiating impedance mapping integration. Together, these two patents would form a credible two-patent licensing package that addresses both the catheter architecture and its integrated sensing capabilities.
Rationale for Abandoning CON-1. The method claims in CON-1 provide incremental enforcement leverage but do not possess substantial independent licensing value beyond what is already available through the Parent Patent. The Parent Patent's 24 claims include method-of-use elements that overlap significantly with CON-1's allowed claims. While the availability of separate method claims can be tactically advantageous in patent litigation — for example, in establishing direct infringement by end-users — this benefit must be weighed against the cost of revival. At $6,090–$7,590 in total revival costs, the incremental value of CON-1's method claims does not justify the expenditure, particularly in a context where SBD's primary objective is cost-effective preservation of licensing value rather than enforcement against specific infringers.
Rationale for Abandoning CON-3. The control-unit/algorithm claims in CON-3 face significant prosecution uncertainty. First, no prior-art search has been conducted on CON-3's specific claims, meaning the prior-art landscape is unknown. Second, algorithm-related claims are subject to heightened scrutiny under 35 U.S.C. § 101 following the Alice decision, and it is possible that the examiner will issue a Section 101 rejection that would require substantial prosecution effort to overcome. Third, the prosecution costs for CON-3 are inherently speculative, as the first Office Action has not yet issued. Fourth, and importantly, the impedance mapping calibration algorithm — which is the most commercially relevant algorithmic feature of the CryoNova system — is partially captured in CON-2's Claims 9–14. By pursuing allowance of CON-2's Claims 9–14, SBD can preserve coverage of the calibration algorithm without the separate cost and risk of prosecuting CON-3.
Licensing Opportunity Assessment
The board should be aware that Pinnacle Health Ventures, as SBD's Series B lead investor holding 34% equity, has expressed interest in preserving the CryoNova IP for potential out-licensing. While we understand that formal licensing negotiations have not yet commenced, the following potential counterparties have been identified:
Helios Surgical Technologies, Inc. Helios is a medical-device intellectual property holding and licensing company headquartered at 750 Bering Drive, Suite 400, Houston, TX 77057. Its CEO is Martin Cheswick. Helios is notable in this context because one of its patents — U.S. Publication No. 2019/0183567 — is among the references cited by the examiner in the CON-2 Office Action. This citation suggests that Helios is active in the impedance monitoring technology space and may have an interest in licensing SBD's impedance mapping integration claims, either for its own portfolio or for sublicensing to its licensees.
Vantage Cryosurgical Systems, Inc. Vantage is a direct competitor to SBD in the cardiac cryoablation market, headquartered at 1420 Gateway Boulevard, South San Francisco, CA 94080. Its CEO is Gerald ("Gerry") Whitford, its VP of intellectual Property is Sandra Leung, and its outside patent counsel is Rachel Okafor at Kessler Brandt & Okafor LLP. Vantage is a significant player in the cryoablation device market with approximately $310 million in annual revenue. Vantage holds a competing cryoablation patent portfolio, including U.S. Patent Nos. 10,537,418 and 9,861,432, both of which are cited in the CON-2 Office Action. Vantage may have interest in licensing the CryoNova IP for freedom-to-operate purposes — particularly if Vantage is developing or planning to develop a next-generation cryoablation catheter with integrated impedance mapping — or in a cross-licensing arrangement that would provide mutual freedom to operate.
We note that the failure of the FROST-AF clinical trial reduces SBD's licensing leverage to some extent, as it introduces uncertainty regarding the commercial viability of products based on the CryoNova technology. However, the underlying patent claims are directed to the catheter technology itself — the variable-zone cooling architecture and the impedance mapping integration — and are technically valid regardless of the clinical trial outcomes. Patent licensing negotiations in the medical device industry routinely involve patents covering technologies that have not been successfully commercialized by the patent holder, and the patents' value is properly assessed based on their claim scope, validity, and relevance to the licensee's own products, not on the patentee's commercial success.
An issued Parent Patent combined with an allowed CON-2 patent would form a credible licensing package without the expense of maintaining the full portfolio. This package would cover both the foundational catheter architecture (Parent) and the commercially differentiating impedance mapping integration (CON-2), providing sufficient breadth to support meaningful licensing discussions.
Assessment. Scenario 2 offers the best balance of cost efficiency and IP value preservation. It eliminates the costs and uncertainties associated with CON-1 revival and CON-3 prosecution while preserving the two most commercially valuable assets in the portfolio. The near-term cost of $20,380–$27,380 is manageable relative to SBD's financial position and is substantially below the cost of Scenario 1. Scenario 2 is our recommended path for board approval.
C. Scenario 3: Full Abandonment
Description. Under Scenario 3, SBD would take no further action with respect to the CryoNova patent family, effectively surrendering all U.S. patent rights in the CryoNova technology. Specifically:
• All pending applications (CON-1, CON-2, and CON-3) would be allowed to go abandoned. CON-1 is already abandoned; CON-2 would become abandoned if no response is filed to the Non-Final Office Action by the applicable deadline (January 15, 2025, or April 15, 2025 if an extension is filed); CON-3 would become abandoned when a first Office Action eventually issues and no response is filed.
• The issued Parent Patent (U.S. Patent No. 11,284,561) would be allowed to lapse by not paying the 3.5-year maintenance fee due September 22, 2025. Upon nonpayment of the maintenance fee, the patent would expire at the end of the six-month grace period (March 22, 2026), subject to the possibility of late payment with a surcharge during the grace period.
• SBD would hold no enforceable U.S. patent rights in the CryoNova technology.
Cost Estimate.
• Incremental cost: $0 — No further professional fees, government fees, or disbursements would be incurred.
We note, however, that the abandonment of patent assets may have accounting implications for SBD. If the CryoNova IP is carried on SBD's balance sheet as an intangible asset, the full abandonment of the portfolio may require a write-down or write-off. SBD should consult with its auditor, Hargrove & Pallister LLP, regarding the appropriate accounting treatment under applicable Irish and international accounting standards (IFRS).
Strategic Considerations. Full abandonment eliminates all ongoing prosecution and maintenance costs associated with the CryoNova patent family. In a resource-constrained environment, this may have appeal as a means of reducing overhead. However, the consequences of full abandonment are severe and, with respect to certain applications, irreversible:
• Irreversibility. Once the response deadlines pass for CON-2 and CON-3, those applications will be deemed abandoned. While petitions to revive for unintentional delay are theoretically available, the deliberate decision not to respond to an Office Action would undermine any claim of unintentional delay, making revival unlikely. Similarly, allowing the Parent Patent to lapse for nonpayment of the maintenance fee would result in the loss of the issued patent, though a six-month grace period with surcharge is available under 35 U.S.C. § 41(b). The practical effect is that a board decision to pursue Scenario 3 should be treated as an irreversible commitment.
• Forfeiture of licensing value. Full abandonment would forfeit all licensing revenue opportunities, including any leverage against Vantage or Helios. The impedance mapping integration claims in CON-2 — which have independent commercial value, as discussed in Section VI.B — would be lost. The Parent Patent's 24 apparatus claims, which currently provide the only issued U.S. patent protection for the CryoNova technology, would also be lost.
• Loss of IP backstop. If SBD or a successor entity were to revisit cryoablation technology in the future — whether through an internal restart of the CryoNova program, a spin-off, or an acquisition — the absence of any patent protection would place SBD at a significant competitive disadvantage. The underlying technology (variable-zone cooling, impedance mapping integration) would enter the public domain upon patent expiration regardless of whether the patents are maintained, but abandonment accelerates the loss of exclusivity by decades.
• Investor expectations. Pinnacle Health Ventures has expressed interest in preserving the CryoNova IP for potential out-licensing. A board decision to pursue full abandonment would need to account for Pinnacle's position, particularly given its 34% equity stake and its role as Series B lead investor. We defer to SBD's management and board on the relationship dynamics with Pinnacle, but note that full abandonment may generate investor concern.
Assessment. Scenario 3 is appropriate only if the SBD board determines, after thorough consideration, that the CryoNova IP has zero residual value, that no licensing market exists or can be developed for the variable-zone cooling and impedance mapping technologies, and that the company has no foreseeable need for patent protection in this technology space. Given the identified licensing opportunities with Helios and Vantage, the Examiner's favorable indication of allowable subject matter in CON-2, and the relatively modest cost of selective prosecution under Scenario 2, we do not recommend Scenario 3.
VII. Comparative Cost Summary
The following table provides a side-by-side comparison of the estimated costs under each scenario:
Note: All government fees are stated at the small-entity rate. SBD qualifies as a small entity (312 employees; no large-entity licensing obligation). Professional fee estimates are based on the current hourly rates of the C&H engagement team and the anticipated scope of work. Actual fees may vary depending on the complexity of prosecution and the extent of client review and coordination required. Future costs for CON-3 prosecution under Scenario 1 are estimated based on typical prosecution experience in Art Unit 3794 but are inherently uncertain, as the first Office Action has not yet been received.
VIII. Recommendation
Based on the analysis set forth in this memorandum, Calderwood & Harkness LLP recommends that the SBD board of directors approve Scenario 2 — Selective Prosecution as the go-forward strategy for the CryoNova patent family.
Our recommendation is grounded in the following considerations:
1. Preservation of the most commercially valuable IP assets at moderate cost. Scenario 2 maintains the two patent assets with the greatest intrinsic and licensing value: the issued Parent Patent (U.S. Patent No. 11,284,561), which provides foundational apparatus claims covering the CryoNova variable-zone cooling catheter system, and the pending CON-2 application (U.S. 17/851,216), which claims the integration of impedance mapping electrodes with the cryoablation catheter. Together, these two assets cover both the catheter platform architecture and its most commercially differentiating feature.
2. Technology-agnostic licensing value of CON-2. CON-2's impedance mapping integration claims have commercial value that is independent of the CryoNova product's fate. The integration of real-time impedance sensing with cryoablation catheter platforms is an emerging industry trend, and CON-2's claims — if allowed — would be relevant to any competitor pursuing this integration, regardless of whether the specific CryoNova product is ever commercialized.
3. Avoidance of costs and uncertainty associated with CON-1 and CON-3. Reviving CON-1 would cost $6,090–$7,590 for method claims that substantially overlap with the Parent Patent's existing claims. Prosecuting CON-3 would involve speculative costs and uncertain patentability, particularly given the potential for Section 101 challenges to the algorithm claims. Scenario 2 eliminates both of these expenditures.
4. Credible licensing package for identified counterparties. The Parent Patent and an issued CON-2 patent would form a credible two-patent licensing package sufficient for meaningful discussions with Helios Surgical Technologies, Inc. and/or Vantage Cryosurgical Systems, Inc., both of which have been identified as potential licensing counterparties.
5. Cost manageability. The near-term cost of $20,380–$27,380 is manageable relative to SBD's €74.3 million annual revenue and represents a prudent investment in preserving IP assets that may generate licensing revenue or strategic value in the future.
6. Alignment with investor expectations. Pinnacle Health Ventures, SBD's largest institutional investor, has expressed interest in preserving the CryoNova IP for potential out-licensing. Scenario 2 is responsive to this interest while exercising appropriate cost discipline.
We believe Scenario 2 strikes the optimal balance between cost efficiency and IP value preservation for SBD. If the board has questions regarding any of the scenarios analyzed in this memorandum, or if additional analysis is required, we are available to discuss at the board's convenience.
IX. Immediate Action Items and Deadlines
The following action items require attention in connection with the go-forward strategy for the CryoNova patent family. We have organized them in order of urgency.
Action Item 1: File Extension of Time for CON-2
Deadline: Before January 15, 2025 (statutory response deadline for the Non-Final Office Action in CON-2)
Action: File a three-month extension of time under 37 C.F.R. § 1.136(a) to extend the CON-2 response deadline from January 15, 2025 to April 15, 2025.
Government Fee: $1,380 (small entity), comprising $230 (first-month extension) + $460 (second-month extension) + $690 (third-month extension).
Status: A draft extension request has been prepared by Wendy Schultz (USPTO Reg. No. 78,115) and is ready for filing upon receipt of client authorization.
Urgency: HIGH. We recommend that the extension be filed immediately upon receipt of board instructions, regardless of which scenario is ultimately selected. Filing the extension is a precautionary measure that preserves all options for the board and costs only $1,380 in government fees. If the board ultimately selects Scenario 3 (Full Abandonment), the extension fee will have been incurred unnecessarily, but this modest cost is justified by the optionality it preserves. Conversely, if the extension is not filed and the January 15, 2025 deadline passes without a response, CON-2 will be deemed abandoned and all prosecution options for the impedance mapping claims will be lost.
Action Item 2: Board Decision on Scenario
Deadline: Before December 31, 2024, to allow adequate time for prosecution preparation under Scenarios 1 or 2.
Action: The SBD board of directors should convene to consider and select among Scenarios 1, 2, and 3 as described in this memorandum.
Requested: C&H requests written instructions from Ronan Gallagher, on behalf of the board, confirming the board's decision. Instructions may be delivered by email to alan.ngo@calderwoodharkness.com and peter.vassiliev@calderwoodharkness.com.
Action Item 3: Prepare and File CON-2 Office Action Response
Deadline: April 15, 2025 (assuming the three-month extension is filed per Action Item 1).