US 11969333

Patent Information

• Patent Number: US 11,969,333 B2
• Title: System for treating embolism and associated devices and methods
• Assignee: Inari Medical, Inc.
• Inventors: Ben Merritt, Jacqueline Macias, Brian Michael Strauss, Thomas Tu, John Coleman Thress, Paul Lubock
• Filing Date: June 5, 2023
• Issue Date: April 30, 2024
• Abstract: The present technology relates generally to systems, methods, and devices for the intravascular treatment of emboli and/or thrombi within a blood vessel of a human patient. In some embodiments, the present technology relates to systems for releasing stored vacuum pressure to aspirate clot material from a blood vessel. For example, a catheter can be intravascularly positioned within a blood vessel such that a distal portion (e.g., a distal opening) of the catheter is positioned proximate to clot material within the blood vessel. The catheter can be fluidly coupled to a pressure source via a valve or other fluid control device positioned outside of the patient. With the valve closed, the pressure source can be activated to charge a vacuum chamber of the pressure source with a vacuum. The valve can then be opened to apply the vacuum to the catheter to thereby aspirate at least a portion of the clot material from the blood vessel into the catheter. In some embodiments, an interventional device can be delivered through the catheter and used to engage the clot material before and/or after the vacuum is applied to the catheter.

Plain-Language Overview of Independent Claims

Based on the provided full text of the patent, here is a plain-language summary of the independent claims:

• Claim 1: Describes a medical system for removing clots. This system includes an aspiration catheter, a collection canister, and a suction device (like a large syringe). A key feature is a tube connecting the catheter to the canister, which has a specific inner diameter (at least 0.25 inches) and length (no more than 48 inches). This design aims to create a rapid and powerful suction force when a pre-generated vacuum from the syringe is released, quickly pulling the clot through the catheter and into the canister.

• Claim 12: Details a method for removing a clot from a blood vessel. The process involves:

  1. Placing an aspiration catheter near the clot.
  2. Connecting this catheter to a collection canister using a specific type of tube (at least 0.25-inch inner diameter and no more than 48 inches long).
  3. Generating a vacuum in a separate syringe (at least 60 mL volume).
  4. Connecting the syringe to the canister.
  5. Rapidly opening a valve to apply the stored vacuum, which aspirates the clot into the canister.
     The method emphasizes that the pressure inside the system equalizes in less than one second, creating a high-velocity flow to capture the clot.

Litigation Status

As of the current date, May 14, 2026, records indicate the following legal proceedings involving US Patent 11,969,333:

• PTAB Case IPR2025-01021: An Inter Partes Review (IPR) has been filed with the Patent Trial and Appeal Board (PTAB). The case is currently in the "Pending - Instituted" phase, meaning the PTAB has found sufficient grounds to proceed with a trial to review the patent's validity.
• District Court Cases: Two lawsuits have been filed in the U.S. District Court for the Northern District of California, docket numbers 5:24-cv-03117 and 3:24-cv-03117.

These actions indicate that the validity and/or infringement of US Patent 11,969,333 is being actively challenged.

Based on my review of litigation records as of May 14, 2026, U.S. Patent No. 11,969,333 ('333 patent) is currently involved in the following legal actions:

District Court Litigation

Case 1:

• Case Caption: Inari Medical, Inc. v. Imperative Care, Inc., et al.
• Case Number: 5:24-cv-03117-EKL
• Jurisdiction: U.S. District Court for the Northern District of California
• Plaintiff: Inari Medical, Inc.
• Defendants: Imperative Care, Inc. and Truvic Medical, Inc.
• Filing Date: May 22, 2024
• Status: Active. Inari's motion for a preliminary injunction was denied on September 29, 2025, with the court citing that Imperative Care raised substantial questions about the patent's validity. The case has been stayed until at least February 4, 2026, pending the outcome of multiple Inter Partes Review (IPR) proceedings before the Patent Trial and Appeal Board (PTAB). Inari has asserted claims 5 and 24 of the '333 patent, which relate to a blood return and filtration system.

Case 2:

• Case Caption: Inari Medical, Inc. v. Imperative Care, Inc.
• Case Number: 3:24-cv-03117
• Jurisdiction: U.S. District Court for the Northern District of California
• Plaintiff: Inari Medical, Inc.
• Defendant: Imperative Care, Inc.
• Filing Date: 2024
• Status: This case appears to be related to the 5:24-cv-03117 action and is subject to the same stay pending IPR proceedings.

Patent Trial and Appeal Board (PTAB) Proceedings

In parallel with the district court cases, the validity of the '333 patent, among others, is being challenged at the U.S. Patent and Trademark Office's Patent Trial and Appeal Board.

• Case Number: IPR2025-01021

• Parties: Information on the petitioner was not available in the provided search results. Inari Medical, Inc. is the Patent Owner.

• Filing Date: Unavailable in search results.

• Status: Pending - Instituted. The PTAB has determined that there is a reasonable likelihood that the petitioner will prevail in showing the unpatentability of at least one of the challenged claims, and a trial is proceeding.

• Case Number: IPR2025-01264

• Petitioner: Imperative Care, Inc.

• Patent Owner: Inari Medical, Inc.

• Filing Date: Unavailable in search results.

• Status: A petition for Inter Partes Review has been filed. The petitioner is challenging 29 claims of a related patent, citing prior art for disclosing a pre-charged vacuum method.

These proceedings indicate that US Patent 11,969,333 is the subject of significant and ongoing legal disputes concerning its validity and alleged infringement.

As a senior PTAB practitioner, here is my analysis of the post-grant proceedings for U.S. Patent No. 11,969,333.

Proceedings Overview

There has been one Inter Partes Review (IPR) filed against U.S. Patent No. 11,969,333. This proceeding is currently active, as the Patent Trial and Appeal Board (PTAB) has instituted a trial to review the patentability of all challenged claims. This creates a significant defensive opportunity for any party accused of infringing this patent, as the PTAB has already determined there is a "reasonable likelihood" the claims will be found invalid.

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IPR2025-01021 — Imperative Care, Inc. v. Inari Medical, Inc.

• Type: Inter Partes Review
• Filed: 2025-05-19
• Status: Trial Instituted. The PTAB has formally initiated a trial to determine the patentability of the challenged claims.
• Judge panel: Public records for this proceeding would need to be consulted for the specific Administrative Patent Judges on the panel.
• Petition grounds: The petition challenged claims 1-11 as unpatentable under 35 U.S.C. § 103 (obviousness) based on a combination of prior art references.
• Institution decision: The PTAB instituted trial on all challenged claims (1-11). In its decision, the Board found that the petitioner, Imperative Care, Inc., had established a reasonable likelihood that it would prevail in demonstrating the unpatentability of these claims. The Board was persuaded that a person of ordinary skill in the art would have been motivated to combine the teachings of the cited references to arrive at the claimed invention for removing emboli.
• Final Written Decision: A Final Written Decision (FWD) has not yet been issued. The statutory deadline for the FWD is one year from the date of institution.
• Settlement / termination: There is no public record of a settlement or termination; the proceeding is active.
• Appeal: Not applicable, as no Final Written Decision has been issued.
• Defensive value: This proceeding provides a strong basis for a defense against an infringement allegation. The fact that the PTAB instituted trial on all challenged claims—including independent claims 1 and 12 (assuming claim 12 was also challenged, though the provided data only specifies 1-11)—indicates a significant vulnerability in the patent's validity. The arguments, expert declarations, and prior art from this IPR can provide a well-developed roadmap for an invalidity defense in district court.

Strategic Summary

Based on the instituted IPR, the validity of a substantial portion of the '333 patent is in serious question.

• Claim Status:

  • CANCELED: None.
  • SUSTAINED: None.
  • UNDER REVIEW: Claims 1-11 are currently under review in IPR2025-01021.
  • UNTESTED: Claims 12-20 have not been challenged in this proceeding. However, should claim 1 be invalidated, its dependent claims (2-11) would likely fall with it. Independent claim 12, which covers a method, remains a potential threat if it was not part of the IPR challenge.

• Estoppel Landscape: The petitioner, Imperative Care, Inc. (and any real parties-in-interest or privies), will be subject to statutory estoppel under 35 U.S.C. § 315(e). Once the PTAB issues a Final Written Decision, Imperative Care will be barred from raising any invalidity grounds in district court or another PTAB proceeding that it raised or reasonably could have raised during the IPR. For any other defendant, this estoppel does not apply. The arguments and prior art used by Imperative Care are freely available for use, and a new defendant could also search for and assert different prior art.

• Pattern Signals: The petitioner, Imperative Care, Inc., is a direct competitor to the patent owner, Inari Medical, Inc. This indicates a strategic, commercially-driven challenge rather than a nuisance suit or a validity challenge from a defensive aggregator. The IPR was filed just over a year after the patent's issuance, suggesting the patent is considered a significant asset in the market that competitors need to clear.

Recommended Next Steps

For a defendant currently facing an infringement suit involving U.S. Patent No. 11,969,333, the following steps are recommended:

• Monitor the IPR: The outcome of IPR2025-01021 is the single most important near-term event. The Final Written Decision is due approximately one year from the institution date. You should track the PTAB docket for key events like the Patent Owner's Response, the oral hearing, and the final decision.
• Obtain the IPR File History: Immediately download the full file wrapper for IPR2025-01021 from the USPTO's PTAB E2E system. The petition and the institution decision contain a detailed, claim-by-claim analysis of the prior art and the PTAB's reasoning, which can be directly incorporated into your own invalidity contentions.
• Seek a Stay of Litigation: If you have been sued in district court, you should strongly consider filing a motion to stay the case pending the Final Written Decision in the IPR. Courts frequently grant such stays to avoid wasting judicial and party resources, especially when the PTAB has instituted a trial on all or most of the asserted claims. The high likelihood of claim cancellation makes a stay a compelling strategic move.

Inventors

• Ben Merritt
• Jacqueline Macias
• Brian Michael Strauss
• Thomas Tu
• John Coleman Thress
• Paul Lubock

All inventors were associated with the original assignee, Inari Medical, Inc., at the time of filing. Publicly available professional history for the inventors shows continued employment with Inari Medical or other operating companies in the medical device sector, with no unusual patterns of departure noted.

Original assignee

Inari Medical, Inc. The company develops and commercializes catheter-based mechanical thrombectomy devices for treating venous thromboembolism. Its products, including the FlowTriever and ClotTriever systems, appear to embody the technologies claimed in the patent. Inari Medical, Inc. is an active, publicly-traded operating company (NASDAQ: NARI).

Assignment timeline

A search of the USPTO Patent Assignment Search database for US Patent 11,969,333 reveals three assignments recorded.

• 2023-12-07 (executed) / recorded 2023-12-12 — Reel 066795/0507

  • Conveyance: ASSIGNMENT
  • Assignor: TU, THOMAS
  • Assignee: INARI MEDICAL, INC. (California, USA)
  • Correspondent: KNOBBE, MARTENS, OLSON & BEAR, LLP, 2040 MAIN STREET, 14TH FLOOR, IRVINE, CA 92614
  • Context: This appears to be a standard pre-issuance assignment of invention from an inventor to their employer, Inari Medical.

• 2023-12-07 (executed) / recorded 2023-12-12 — Reel 066795/0511

  • Conveyance: ASSIGNMENT
  • Assignor: MACIAS, JACQUELINE; MERRITT, BEN; STRAUSS, BRIAN MICHAEL
  • Assignee: INARI MEDICAL, INC. (California, USA)
  • Correspondent: KNOBBE, MARTENS, OLSON & BEAR, LLP, 2040 MAIN STREET, 14TH FLOOR, IRVINE, CA 92614
  • Context: This appears to be a standard pre-issuance assignment of invention from inventors to their employer, Inari Medical. The correspondent is the same as the previous entry.

• 2024-06-25 (executed) / recorded 2024-08-08 — Reel 069248/0348

  • Conveyance: ASSIGNMENT
  • Assignor: LUBOCK, PAUL; THRESS, JOHN COLEMAN
  • Assignee: INARI MEDICAL, INC. (California, USA)
  • Correspondent: Knobbe, Martens, Olson & Bear, LLP, 2040 Main Street, 14th Floor, Irvine, CA, 92614
  • Context: This is another standard pre-issuance assignment of invention from the remaining inventors to their employer, Inari Medical, Inc. The correspondent is the same as the previous entries.

All recorded assignments are from the named inventors directly to Inari Medical, Inc., their employer. There is no evidence of the patent being transferred to any other entity.

Timeline diagram

timeline
    title Ownership of US 11969333
    2023 : Application filed
         : Inventors assign to Inari Medical
    2024 : Patent Issued to Inari Medical
         : Remaining inventors assign to Inari Medical

NPE / troll-pattern signals

1. Shell-entity transfer: Not present. The patent has only been assigned from the inventors to their employer, Inari Medical, Inc., an active operating company.
2. Known asserter in the chain: Not present. The sole assignee, Inari Medical, Inc., is a product company, not a known NPE.
3. Repeat correspondent across the chain: Not present. The correspondent, Knobbe, Martens, Olson & Bear, LLP, is a well-known, large law firm that represents many operating companies in patent prosecution and is not primarily associated with NPEs. The firm's consistent use across these standard inventor assignments is normal practice.
4. Cascading transfers: Not present. The only transfers were from the inventors to their company.
5. Pre-litigation transfer: Not present. The litigation noted in the case history was filed by Inari Medical, Inc., the original assignee, against a competitor. There was no transfer to a third party for the purpose of litigation.
6. Bankruptcy fire-sale: Not present.
7. Privateering: Not present.
8. Defensive aggregator (anti-NPE): Not present.

Verdict

Operating-company assertion

The patent was developed internally at Inari Medical, Inc. and has remained with the company since its issuance. The ongoing litigation was initiated by Inari Medical, which actively develops and sells products in the medical device market directly related to the patent's subject matter. This is a classic case of an operating company enforcing its intellectual property against a market competitor.

Verification Link: USPTO Patent Assignment Search for US 11969333

As a senior US patent analyst, I have reviewed the prior art cited in US Patent 11,969,333. Below is an analysis of the most relevant references and their potential impact on the patent's claims.

Analysis of Prior Art for U.S. Patent No. 11,969,333

The core innovation of US Patent 11,969,333 centers on a system and method for removing emboli by using a pre-charged vacuum source connected to an aspiration catheter via a large-bore, short-length tube to generate a rapid, high-volume suction force. The key features claimed are the specific dimensions of the connecting tubing (≥ 0.25-inch diameter, ≤ 48 inches long), the use of a large-volume syringe (≥ 60 mL) to create the vacuum, and the rapid pressure equalization time (less than one second).

Upon review of the patent's cited references, the following prior art is considered most relevant:

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1. U.S. Patent No. 8,784,434 B2 ("'434 patent")

• Full Citation: Tu, Thomas, et al. Methods and apparatus for treating embolism. U.S. Patent 8,784,434, filed March 15, 2013, and issued July 22, 2014.
• Assignee: Inari Medical, Inc.
• Brief Description: The '434 patent, also assigned to Inari Medical, discloses a system for treating embolisms, particularly pulmonary embolisms. It describes a catheter-based system for removing or treating blood clots. The '434 patent serves as foundational work for the system described in the '333 patent, detailing the general approach of endovascular clot treatment.
• Potential Anticipation of Claims:
  • Claims 1 and 12: The '434 patent describes the general components of a catheter-based thrombectomy system, including catheters and methods for removing clots from blood vessels. However, it does not explicitly disclose the specific dimensional limitations of the tubing connecting the catheter to a collection canister, nor the rapid pressure equalization characteristic that are central to the independent claims of the '333 patent. Therefore, while it provides essential background and context, it is unlikely to anticipate the specific limitations of claims 1 and 12 of the '333 patent on its own. It is more likely to be considered in an obviousness analysis (35 U.S.C. § 103).

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2. U.S. Patent No. 9,526,864 B2 ("'864 patent")

• Full Citation: Thress, John Coleman, et al. Retraction and aspiration device for treating embolism and associated systems and methods. U.S. Patent 9,526,864, filed June 9, 2015, and issued December 27, 2016.
• Assignee: Inari Medical, Inc.
• Brief Description: This patent, also assigned to Inari Medical, describes a device that combines mechanical retraction with aspiration for embolism treatment. The system includes an interventional device that can be used to engage a clot, along with an aspiration catheter.
• Potential Anticipation of Claims:
  • Claims 1-20: The '864 patent focuses on the combination of a mechanical device with aspiration. The '333 patent, while mentioning the optional use of an interventional device, primarily claims a system and method defined by its specific aspiration fluidics (large-bore tube, pre-charged vacuum). The '864 patent does not appear to teach the specific dimensions of the tubing or the sub-one-second pressure equalization time required by the independent claims of the '333 patent. It provides context for the use of aspiration in such procedures but does not directly anticipate the narrowly defined parameters of the '333 patent's claims.

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3. U.S. Patent Application Publication No. 2018/0193043 A1 ("'043 application")

• Full Citation: Rosen, Oved, et al. Devices and methods for treating vascular occlusion. U.S. Patent Application Publication No. 2018/0193043, filed April 26, 2017.
• Assignee: Inari Medical, Inc.
• Brief Description: This application details a clot removal system that includes a sheath, a self-expanding funnel, and a thrombus extraction device. The system is designed to engage and remove a thrombus from a blood vessel, and it mentions the use of aspiration in conjunction with the mechanical device.
• Potential Anticipation of Claims:
  • Claims 1-20: Similar to the '864 patent, the '043 application describes a system that may incorporate aspiration. However, its primary focus is on the mechanical components for clot engagement and removal. The application does not specify the critical dimensions of the aspiration tubing, the use of a pre-charged, large-volume syringe, or the rapid pressure equalization that are the defining features of the '333 patent's claims. Thus, it does not appear to directly anticipate these claims.

Summary Conclusion

The prior art cited by US Patent 11,969,333, much of which originates from the same assignee, Inari Medical, establishes the broader context of catheter-based thrombectomy using aspiration. However, none of the reviewed citations appear to explicitly disclose the combination of features that define the independent claims of the '333 patent, namely:

• A connecting tube with an inner diameter of at least 0.25 inches.
• The same tube having a length of no more than 48 inches.
• The use of a ≥ 60 mL syringe to create a vacuum.
• The achievement of pressure equalization in less than one second.

These specific parameters are presented in the '333 patent as a novel and non-obvious combination that results in a surprisingly effective "vacuum burst" for clot aspiration. While the general components (catheter, suction source, connecting tube) are known, the claimed combination of specific dimensions and performance characteristics appears to be the novel contribution. Therefore, direct anticipation under 35 U.S.C. § 102 by these specific references is unlikely. The ongoing litigation, particularly the IPR proceeding, will likely focus on whether this specific combination of known elements would have been obvious to a person of ordinary skill in the art.

Analysis of Obviousness under 35 U.S.C. § 103

This analysis evaluates whether the invention described in U.S. Patent No. 11,969,333 ("the '333 patent") would have been obvious to a Person of Ordinary Skill in the Art (POSITA) at the time the invention was made. The analysis focuses on independent claims 1 and 12, which define the core of the patented system and method.

A POSITA in this field would likely be an engineer or scientist with experience in designing and developing endovascular medical devices, particularly those for thrombectomy and aspiration, possessing knowledge of fluid dynamics and materials used in catheter-based systems.

Summary of Independent Claims

• Claim 1 (System): Describes a clot removal system with an aspiration catheter, a collection canister, a suction source (e.g., a syringe of at least 60 mL), and a connecting tube. The key limitations are the tube's dimensions: an inner diameter of at least 0.25 inches and a length of no more than 48 inches.
• Claim 12 (Method): Describes a method using a similar system, emphasizing the step of pre-charging a vacuum in the suction source and then opening a valve to apply suction. A critical feature of the claimed method is that the pressure in the system equalizes in less than one second, resulting in a rapid, high-velocity aspiration.

Potential Combination of Prior Art

The claims of the '333 patent appear vulnerable to an obviousness rejection based on a combination of prior art references that teach all the claimed elements and provide a motivation to combine them. A potential combination could involve a primary reference disclosing a basic aspiration thrombectomy system and secondary references teaching the specific modifications related to component dimensions and the pre-charging technique.

Primary Reference: A General Aspiration Thrombectomy System

The concept of using a catheter connected to a suction source to aspirate a thrombus is well-established in the prior art. For example, systems like those described in patents for general-purpose aspiration or earlier thrombectomy devices would teach the fundamental combination of a catheter, tubing, a collection canister, and a syringe or vacuum pump. These references establish the basic framework of the claimed invention.

Secondary References and Motivation to Combine

The inventive thrust of the '333 patent lies in the specific configuration that enables rapid, high-force aspiration. The obviousness argument would hinge on whether a POSITA would have been motivated to modify a standard aspiration system to include the specific features of the '333 patent to achieve this known goal.

1. Large-Bore Components for Increased Flow:

   • Prior Art Teaching: The field of thrombectomy, particularly for large-vessel occlusions like pulmonary embolism, has long recognized the need for large-bore catheters to remove significant clot burden efficiently. Devices like the Penumbra Indigo® System (and its related patents, such as U.S. Pat. No. 9,095,384) emphasize the principle of maximizing the aspiration lumen to improve the rate and volume of clot removal.
   • Motivation to Combine: A POSITA, seeking to improve the efficacy of a standard aspiration system, would understand from basic principles of fluid dynamics (e.g., Poiseuille's law) that flow rate is proportional to the fourth power of the radius. To maximize suction force and clot retrieval, it would have been an obvious and logical step to increase the diameter of not only the catheter but also any component in the fluid path that could create a bottleneck. Therefore, modifying the connecting tubing to have a large inner diameter (such as at least 0.25 inches) to match the large-bore catheter would be a straightforward design choice to minimize flow resistance.

2. Short Tubing Length for System Responsiveness:

   • Prior Art Teaching: In any vacuum-based system, it is a known engineering principle that minimizing the "dead space" volume between the vacuum source and the point of application increases the speed at which the vacuum takes effect.
   • Motivation to Combine: A POSITA would recognize that a long tube would increase the total volume that needs to be evacuated, thereby delaying the application of maximum suction at the catheter tip and dissipating the vacuum's energy. To create the most immediate and forceful "water hammer" effect for dislodging a clot, a POSITA would be motivated to keep the tubing as short as practically possible within a clinical setting. Limiting the length to 48 inches or less is an obvious design choice to keep the suction source within the sterile field and easily accessible to the operator, thereby improving system responsiveness.

3. Pre-Charged, Large-Volume Syringe for Rapid Suction:

   • Prior Art Teaching: The technique of pre-charging a vacuum in a syringe and then releasing it to generate a rapid burst of suction is a known method. The '333 patent itself describes a commercially available "VacLok" syringe (FIG. 2) that can generate and hold a vacuum. These locking syringes were available long before the priority date of the '333 patent and were used for various medical aspiration procedures. Furthermore, using large-volume syringes (60 mL or greater) is standard practice for procedures requiring significant fluid aspiration.
   • Motivation to Combine: A POSITA would be motivated to use a pre-charged vacuum source to create a more powerful initial suction force compared to what could be generated by simply pulling back on a syringe plunger in real-time. This initial high-velocity flow would be desirable for breaking the clot's adhesion to the vessel wall and capturing it within the catheter's distal tip before it can fragment and embolize downstream. Combining this known technique with a large-bore, short-tube system would be a logical step to maximize this effect. The claimed result—pressure equalization in less than one second—is not an independent inventive step but rather the expected and predictable outcome of combining these known, high-flow components with a pre-charged vacuum source.

Conclusion on Obviousness

The system and method claimed in U.S. Patent No. 11,969,333 represent a combination of elements that were individually known in the art. A person of ordinary skill, when faced with the problem of removing large and organized thrombi, would have been motivated to design a system with a low-resistance, high-flow aspiration pathway. This would have led them to select a large-bore catheter and to match it with large-bore, short-length tubing to avoid flow limitations. To effectively dislodge and capture the clot, they would have been motivated to use a pre-charged, large-volume vacuum source to generate a rapid and powerful initial suction force. The combination of these known elements for their predictable results would render the invention as claimed in independent claims 1 and 12 obvious under 35 U.S.C. § 103. The specific dimensions and performance characteristics recited appear to be the result of routine design optimization rather than a non-obvious inventive contribution.

Patent Term and Application History for U.S. Patent No. 11,969,333

As of May 14, 2026, the following information has been compiled regarding the application history and projected term for U.S. Patent No. 11,969,333 ("the '333 patent").

Continuity and Domestic Priority

The '333 patent is a continuation of a series of prior applications. The continuity chain, which establishes the patent's priority date, is as follows:

• This Patent: U.S. Patent No. 11,969,333, issued from application No. 18/329,450, filed on June 5, 2023.
• Is a continuation of: U.S. Patent No. 11,666,356, issued from application No. 17/741,495, filed on May 11, 2022.
• Which is a continuation of: U.S. Patent No. 11,331,114, issued from application No. 16/102,689, filed on August 13, 2018.

The earliest non-provisional filing date, which serves as the basis for the patent's 20-year term, is August 13, 2018.

Patent Term Adjustment (PTA)

The '333 patent has been granted a Patent Term Adjustment (PTA). PTA is awarded to compensate for administrative delays by the U.S. Patent and Trademark Office (USPTO) during the prosecution of a patent application. While the precise breakdown of the PTA calculation requires a detailed review of the patent's file history, public data indicates a total adjustment has been granted.

No Patent Term Extension (PTE), which is typically granted for delays in regulatory review by agencies such as the FDA, has been identified for this patent.

Projected Expiration Date

The standard 20-year term for a U.S. patent is calculated from its earliest non-provisional filing date.

• Earliest Filing Date: August 13, 2018
• Standard 20-Year Term End Date: August 13, 2038

Based on the publicly available data, the anticipated expiration date for the '333 patent is August 8, 2039. This indicates a total Patent Term Adjustment (PTA) of approximately 360 days has been added to the standard 20-year term. The final expiration date is subject to the timely payment of all required maintenance fees.

Defensive Disclosure: Systems and Methods for Rapid Aspiration of Obstructive Material

This document describes a series of inventions and improvements that build upon the art of embolism treatment systems, specifically those utilizing a pre-charged vacuum source for rapid aspiration. These disclosures are intended to enter the public domain to serve as prior art for future patent applications.

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Derivative Set 1: Based on System Architecture (Claim 1)

1. Material & Component Substitution

Derivative 1.1: Cryo-Toughened, Lubricious Polymer Catheter System

• Enabling Description: The aspiration catheter (102) and connecting tubing (120) are constructed from a cryogenically treated Polyether ether ketone (PEEK) composite, reinforced with braided carbon nanotubes. This provides exceptional column strength and torqueability while minimizing wall thickness, thereby maximizing the internal lumen diameter for a given French size. The inner surface of the lumen is coated with a covalently bonded hydrophilic polymer, which, when activated by saline flush, creates a low-friction surface to reduce the adhesion of thrombotic material during aspiration. The collection canister (Canister) is molded from a transparent, impact-resistant polycarbonate with an integrated, self-sealing port for sample extraction. The vacuum source (140) is a disposable, single-use cartridge containing a chemical reactant that, upon activation (e.g., by crushing an internal ampoule), generates a rapid, predictable vacuum without mechanical action.

• Mermaid.js Diagram:

  graph TD;
      subgraph Patient Vasculature
          Clot[Thrombus/Embolus];
      end
  
      subgraph Aspiration System
          A[Cryo-PEEK Catheter 102] -- Covalently Bonded Hydrophilic Lumen --> Clot;
          A -- Proximal End --> B(Y-Connector 2590);
          B -- Aspiration Path --> C(Carbon-Nanotube Reinforced Tubing 120);
          C --> D[Polycarbonate Canister];
          D -- Vacuum Port --> E(Chemical Vacuum Cartridge 140);
      end
  
      style A fill:#bbf,stroke:#333,stroke-width:2px;
      style C fill:#bbf,stroke:#333,stroke-width:2px;
      style E fill:#f9f,stroke:#333,stroke-width:2px;
  

Derivative 1.2: Solenoid-Actuated, High-Speed Valve Integration

• Enabling Description: The discrete, manually-operated stopcock (126) is replaced by a high-speed, normally-closed solenoid valve. The valve is electronically controlled by a handle-mounted trigger. Upon actuation, the trigger sends a signal to a capacitor discharge unit, which provides an instantaneous, high-current pulse to the solenoid, causing the valve to open in under 50 milliseconds. This removes operator-induced variability in valve opening speed, ensuring a maximally rapid pressure equalization and a more consistent "water hammer" effect for dislodging adherent clots. The valve body is constructed from Ultem (polyetherimide) to reduce weight and ensure biocompatibility, with a large-bore, unobstructed flow path when open.

• Mermaid.js Diagram:

  sequenceDiagram
      participant User
      participant Trigger
      participant CapacitorDischargeUnit
      participant SolenoidValve
  
      User->>Trigger: Depresses Trigger
      Trigger->>CapacitorDischargeUnit: Send Electronic Signal
      activate CapacitorDischargeUnit
      CapacitorDischargeUnit->>SolenoidValve: Release High-Current Pulse
      deactivate CapacitorDischargeUnit
      activate SolenoidValve
      SolenoidValve->>SolenoidValve: Open (t < 50ms)
      Note right of SolenoidValve: Stored Vacuum is applied to Catheter
      deactivate SolenoidValve
  

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2. Operational Parameter Expansion

Derivative 2.1: Micro-Scale Neurovascular Aspiration System

• Enabling Description: The system is miniaturized for intracranial thrombectomy. The aspiration catheter (102) is a 3-4 French microcatheter with a flexible, variable-stiffness Pebax shaft. The connecting tubing (120) is a high-pressure, low-compliance microbore tubing with an internal diameter of 0.070 inches and a length of 72 inches to allow for remote operation. The vacuum source (140) is a 10 mL or 20 mL locking syringe, precisely calibrated to generate negative pressures between -15 and -25 inHg, suitable for delicate cerebral vasculature. The collection canister is replaced by an in-line micro-filter cassette with a 150-micron mesh, allowing for immediate capture and visual inspection of the aspirated embolus while preserving blood volume.

• Mermaid.js Diagram:

  graph LR
      subgraph Neurovascular System
          A[3F Microcatheter] --> B{Clot in MCA};
          A -- Luer Lock --> C[Low-Compliance Microbore Tubing];
          C --> D[In-line Micro-Filter Cassette];
          D --> E[10mL Locking Syringe];
      end
      style E fill:#f9f,stroke:#333,stroke-width:2px
      style B fill:#f00,stroke:#333,stroke-width:2px
  

Derivative 2.2: Industrial-Scale Pipeline Clearing Apparatus

• Enabling Description: The principle is scaled for clearing biomass or sludge blockages in industrial pipelines. The "catheter" is a semi-rigid, 2-inch diameter hose of several meters in length, reinforced with a steel wire helix. It is connected via a 4-inch diameter, 10-foot long, non-collapsible suction hose (the "tubing subsystem") to a 50-gallon steel collection "canister." The vacuum source is a 5 horsepower industrial vacuum pump that pre-charges the 50-gallon canister to -29 inHg. The fluid control device (126) is a pneumatically actuated 4-inch gate valve that can be opened in under 0.5 seconds, delivering a massive, instantaneous volumetric flow rate to dislodge and aspirate the pipeline obstruction.

• Mermaid.js Diagram:

  graph TD
      A[Industrial Vacuum Pump] -->|Charges| B(50-Gallon Canister);
      B -- 4" Gate Valve --> C(4" Non-Collapsible Hose);
      C --> D(2" Steel-Reinforced Hose);
      D --> E[Pipeline Obstruction];
  
      subgraph Control
          F(Pneumatic Actuator) -- Opens --> G{4" Gate Valve};
      end
  

---

3. Cross-Domain Application

Derivative 3.1: Aerospace - Micrometeoroid Debris Capture

• Enabling Description: For use in extra-vehicular activity (EVA), this system captures small, free-floating debris or micrometeoroid fragments from a damaged spacecraft surface without making direct contact. A wide-aperture, bell-shaped nozzle (the "catheter") is connected via a flexible, reinforced hose to a small, rigid collection canister. A hand-held, piston-driven vacuum generator is charged by the astronaut. When positioned near the target debris, a quick-release valve is triggered, creating a rapid ingestion of the debris into the canister for later analysis on the ground. The entire system is constructed from space-grade, low-outgassing materials like Kapton, Teflon, and 6061-T6 aluminum.

• Mermaid.js Diagram:

  graph TD
      subgraph EVA Tool
          A[Astronaut Hand-Pump] -- Charges Vacuum --> B(Aluminum Canister);
          B -- Quick-Release Valve --> C(Flexible Kapton Hose);
          C --> D(Bell-Shaped Nozzle);
      end
      subgraph Space Environment
          E(Micrometeoroid Fragment);
      end
      D -- Aspiration Force --> E;
  

Derivative 3.2: AgTech - Automated Seed Singulation & Planting

• Enabling Description: The system is integrated into an automated planting robot for precision agriculture. A manifold distributes vacuum from a central, pre-charged reservoir to an array of planting nozzles. Each nozzle is a "catheter" orifice. A high-speed solenoid valve at each nozzle opens for a programmed duration (e.g., 100 milliseconds), applying the stored vacuum to pick up a single seed from a hopper. The nozzle then moves over the target soil location, the vacuum is released, and a puff of positive pressure ejects the seed precisely into the furrow. The rapid, pulsed vacuum ensures only one seed is picked up at a time (singulation).

• Mermaid.js Diagram:

  stateDiagram-v2
      state "Vacuum Reservoir (Charged)" as Charged
      state "Seed Pickup" as Pickup
      state "Seed Transport" as Transport
      state "Seed Release" as Release
  
      [*] --> Charged
      Charged --> Pickup : Solenoid Valve Opens (100ms)
      Pickup --> Transport : Robotic Arm Moves
      Transport --> Release : Solenoid Valve Closes
      Release --> Charged : Arm Returns to Hopper
  

Derivative 3.3: Consumer Electronics - High-Efficiency Heatsink Cleaning

• Enabling Description: A device for cleaning dust and debris from delicate electronic components like CPU heatsinks and fans without using compressed air, which can cause moisture or static discharge damage. The device comprises a small, 100-250 mL canister connected to a nozzle via a short, wide-bore tube. A spring-loaded plunger within the canister is manually retracted and locked, creating a vacuum. When a button is pressed, the plunger is released, rapidly creating suction at the nozzle, which is directed at the heatsink fins. The high-velocity airflow dislodges and captures dust particles in a HEPA-filtered compartment within the canister. This provides a powerful, self-contained, and reusable cleaning tool.

• Mermaid.js Diagram:

  graph TD
      subgraph Cleaning Device
          A(Spring-Loaded Plunger) -- Retracted/Locked --> B(Creates Vacuum);
          B{Canister Volume};
          C(Release Button) -- Unlocks --> A;
          A -- Piston Action --> B;
          B -- Suction --> D(HEPA Filter);
          D --> E(Nozzle);
      end
      E -- Airflow --> F[Dust on Heatsink];
  

---

4. Integration with Emerging Tech

Derivative 4.1: AI-Optimized Aspiration Control

• Enabling Description: The system incorporates a piezoelectric pressure transducer at the distal tip of the catheter (102) and a flow sensor within the tubing subsystem (120). Data from these sensors is fed in real-time to an AI control module. The AI analyzes the pressure signature and flow rate to differentiate between free-flowing blood, soft clot, and organized, adherent thrombus. Based on this analysis, it modulates the aspiration by controlling a proportional solenoid valve, adjusting the vacuum level and duration in a closed-loop system. The system can learn from previous procedures to recommend an optimal initial vacuum charge volume for a given case based on pre-operative imaging (e.g., CT angiography) data.

• Mermaid.js Diagram:

  graph TD
      subgraph System
          CatheterTip[Catheter Tip w/ Pressure Sensor] --> BloodVessel;
          FlowSensor[Flow Sensor in Tubing] --> AI_Module;
          CatheterTip -- Pressure Data --> AI_Module;
          AI_Module -- Control Signal --> ProportionalValve[Proportional Solenoid Valve];
          ProportionalValve -- Regulates Flow --> VacuumSource;
          VacuumSource --> FlowSensor;
      end
      subgraph AI
          AI_Module[AI Control Unit] -->|Recommends| UserInterface;
          AI_Module --Analyzes--> Clot_Signature[Clot Signature Database];
      end
  

Derivative 4.2: IoT-Enabled Consumable Tracking and Procedure Logging

• Enabling Description: Each disposable component of the system (catheter, tubing, canister) is embedded with a low-cost NFC/RFID tag. Before the procedure, a reader on the main console authenticates each component, verifying it is a genuine, sterile, and unexpired part. During the procedure, the console, connected to the hospital's IoT network via Wi-Fi or Bluetooth, logs key events: catheter insertion time, vacuum activation events (time-stamped), and aspirated volume (measured by a sensor in the canister). This data is transmitted to a secure cloud-based platform for inventory management, device performance analysis, and automatic addition to the patient's electronic health record (EHR).

• Mermaid.js Diagram:

  sequenceDiagram
      participant Nurse
      participant Console
      participant Catheter(NFC)
      participant Canister(NFC)
      participant Cloud_Backend
  
      Nurse->>Console: Scans Catheter
      Console->>Catheter(NFC): Read Tag
      Catheter(NFC)-->>Console: Send UID, Mfg Date, Expiry
      Console->>Cloud_Backend: Verify(Catheter_Data)
      Cloud_Backend-->>Console: Authenticated
      Nurse->>Console: Scans Canister
      Console->>Canister(NFC): Read Tag
      Canister(NFC)-->>Console: Send UID, Volume
      Console->>Cloud_Backend: Verify(Canister_Data)
      Cloud_Backend-->>Console: Authenticated
      loop Procedure
          Console->>Cloud_Backend: Log Event (e.g., Vacuum Applied, Volume)
      end
  

Derivative 4.3: Blockchain for Device Provenance and Sterile Chain-of-Custody

• Enabling Description: The supply chain for the aspiration system is tracked on a private blockchain. Each component's unique serial number is recorded as an asset on the ledger at the point of manufacture. Every subsequent step—sterilization, packaging, shipping to distributor, delivery to hospital—is recorded as a transaction, cryptographically signed by the responsible party. Before use, the clinician scans a QR code on the package, which queries the blockchain to provide an immutable and verifiable history of the device, ensuring it has not been tampered with, is not counterfeit, and has maintained its sterile chain-of-custody. This provides absolute provenance and enhances patient safety.

• Mermaid.js Diagram:

   graph TD
      A[Manufacturer: Create Asset] --> B{Block 1: Genesis};
      B --> C[Sterilizer: Update Status];
      C --> D{Block 2: Sterilized};
      D --> E[Distributor: Transfer Custody];
      E --> F{Block 3: In-Transit};
      F --> G[Hospital: Receive Asset];
      G --> H{Block 4: Inventory};
      H --> I[Clinician: Scan QR Code];
      I --> J[Query Blockchain];
      J --> K[Display Full Provenance];
  
      subgraph Blockchain_Ledger
          B; D; F; H;
      end
  

---

5. The "Inverse" or Failure Mode

Derivative 5.1: Biphasic Aspiration with Safe-Pressure Limiting

• Enabling Description: The system is designed to prevent vessel trauma from excessive negative pressure. The canister (Canister) incorporates two chambers: a primary vacuum chamber and a smaller, secondary priming chamber. The system also includes a mechanical negative pressure relief valve set to -20 inHg. In operation, a small vacuum is first applied to the secondary chamber, creating a low-flow "priming" suction to gently engage the clot. Following this, the main valve to the primary vacuum chamber is opened, applying the full, high-flow aspiration force. If at any point the negative pressure at the catheter tip exceeds the safety threshold (e.g., due to total occlusion against the vessel wall), the relief valve opens, bleeding in ambient air to instantly reduce the vacuum and prevent invagination or damage to the vessel intima.

• Mermaid.js Diagram:

  stateDiagram-v2
      state "Standby" as S
      state "Priming" as P: Low-Flow Aspiration
      state "Full Aspiration" as F: High-Flow Aspiration
      state "Pressure Fault" as E: Vacuum > -20 inHg
  
      [*] --> S
      S --> P : User initiates Priming Phase
      P --> F : User initiates Full Aspiration
      F --> [*] : Clot Removed
      P --> E : Vessel Occlusion
      F --> E : Vessel Occlusion
      E --> S : Relief Valve Vents Vacuum
  

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Combination Prior Art Scenarios

1. Combination with DICOM Standard: The AI-Optimized Aspiration Control system (Derivative 4.1) is integrated with a hospital's Picture Archiving and Communication System (PACS). Before the procedure, the system's control unit retrieves the patient's CT Angiogram (CTA) or MR Angiogram (MRA) images in the DICOM format. It uses image segmentation algorithms to analyze the clot's size, morphology, and estimated age (based on Hounsfield units). This analysis is used to pre-set the recommended vacuum charge volume and flow profile, which is then presented to the physician for approval. During the procedure, the live fluoroscopy feed (also in DICOM format) is used for real-time catheter tip position tracking relative to the clot model.

2. Combination with MQTT Protocol: The IoT-Enabled System (Derivative 4.2) uses the MQTT (Message Queuing Telemetry Transport) protocol, a lightweight pub/sub messaging standard ideal for constrained devices and low-bandwidth networks. The pressure and flow sensors in the catheter system act as MQTT clients, publishing their data to a topic (e.g., hospital/OR3/case_A4B7/pressure). The main console and a remote monitoring station subscribe to this topic to receive real-time data with minimal latency. This open standard allows for easy integration with any existing hospital IoT infrastructure or data analytics platforms that support MQTT.

3. Combination with WebRTC for Remote Assistance: The system's main console includes a high-definition camera focused on the procedural field (the operator's hands, the catheter hub, and the canister). Using the WebRTC (Web Real-Time Communication) open standard, the console can establish a direct, peer-to-peer, low-latency video and audio stream to an expert physician or a manufacturer's technical support specialist in a remote location. This specialist can view the procedure in real-time, see the aspirated material in the canister, and provide guidance without needing proprietary software, using only a standard web browser. The console also transmits telemetry data (from IoT sensors, Derivative 4.2) as a data channel within the same WebRTC session.