DCT
2:21-cv-00337
Khan v. Merit Medical Systems Inc
I. Executive Summary and Procedural Information
- Parties & Counsel:
- Plaintiff: Nazir Khan and Iftikhar Khan (Illinois)
- Defendant: Merit Medical System Inc. (Utah)
- Plaintiff’s Counsel: Pro Se
- Case Identification: 2:21-cv-00337, D. Utah, 06/01/2021
- Venue Allegations: Venue is alleged to be proper in the District of Utah because the defendant, Merit Medical Systems Inc., resides there.
- Core Dispute: Plaintiffs allege that Defendant’s HeRO Graft, a device for hemodialysis access, infringes a patent related to a hybrid arteriovenous shunt system.
- Technical Context: The technology concerns medical devices for providing long-term vascular access for hemodialysis patients, aiming to reduce complications like vein damage and clotting associated with traditional methods.
- Key Procedural History: The complaint discloses a prior lawsuit filed by the Plaintiffs in the Northern District of Illinois (No. 18-cv-5368) against Merit Medical and other defendants, which was dismissed with prejudice on grounds of improper venue and service. The dismissal was affirmed by the U.S. Court of Appeals for the Federal Circuit. The complaint also notes that the patent-in-suit was granted after the Patent Trial and Appeal Board overcame an anticipation rejection.
Case Timeline
| Date | Event |
|---|---|
| 2004-03-29 | Priority Date for U.S. Patent No. 8,747,344 |
| 2012-10-09 | Issue Date for related U.S. Patent No. 8,282,591 |
| 2014-06-10 | Issue Date for U.S. Patent No. 8,747,344 |
| 2016-02-04 | Merit Medical acquires the HeRO Graft from CryoLife Inc. |
| 2018-08-07 | Plaintiffs file prior lawsuit in N.D. Illinois |
| 2020-08-13 | Federal Circuit affirms dismissal of prior lawsuit |
| 2021-06-01 | Complaint Filing Date |
II. Technology and Patent(s)-in-Suit Analysis
U.S. Patent No. 8,747,344 - "HYBRID ARTERIOVENOUS SHUNT" (issued June 10, 2014)
The Invention Explained
- Problem Addressed: The patent addresses the high failure rate of conventional arteriovenous (AV) grafts and fistulas used for hemodialysis access. These methods often return high-pressure, turbulent blood flow from a dialysis machine directly into a patient’s vein, causing damage, neointimal hyperplasia (cell growth that narrows the vessel), clotting, and eventual failure of the access site (’344 Patent, col. 1:48-61).
- The Patented Solution: The invention is a "hybrid arteriovenous shunt" system that avoids returning high-pressure blood directly to a fragile vein. It uses a flexible arterial graft connected to a single-lumen venous outflow catheter via a connecting cuff. The catheter is routed through a vein but terminates in the right atrium of the heart, depositing the purified blood directly into the central circulation. This configuration is intended to bypass the peripheral venous system, thereby preventing the pressure-induced damage that leads to access failure (’344 Patent, Abstract; col. 2:10-20). The patent’s Figure 2 illustrates this "arterioatrial" path (’344 Patent, Fig. 2).
- Technical Importance: By creating a path that deposits purified blood into the high-flow environment of the right atrium, the invention sought to provide a more durable, long-term hemodialysis access solution with lower rates of stenosis and thrombosis (’344 Patent, col. 2:15-20).
Key Claims at a Glance
- The complaint asserts independent claim 13.
- Claim 13 is a system claim written in means-plus-function format pursuant to 35 U.S.C. § 112, para. 6 (now § 112(f)). Its essential elements are:
- An arteriovenous shunt means, which itself comprises:
- An "arterial graft means" for connection to an artery.
- A "single lumen venous outflow catheter means" for insertion into the right atrium of the heart.
- A "cuff means" for connecting the graft means and the catheter means, wherein the cuff is disposed about both components and provides a secure fit.
- A "hemodialysis apparatus."
- An arteriovenous shunt means, which itself comprises:
- The complaint does not explicitly reserve the right to assert dependent claims.
III. The Accused Instrumentality
Product Identification
- The accused instrumentality is the "HeRO Graft" device (Compl. ¶[p. 2]).
Functionality and Market Context
- The complaint describes the HeRO Graft as a device used for hemodialysis that consists of three main components: an arterial graft (6 mm diameter), a "metallic connector," and a venous outflow catheter (5 mm diameter) designed to be placed in the right atrium of the heart (Compl. ¶[p. 5]).
- Functionally, the HeRO Graft is alleged to operate identically to the claimed invention by creating a circuit for hemodialysis where blood is transmitted from the arterial graft, purified, and returned via the venous outflow catheter directly to the right atrium (Compl. ¶¶[pp. 5-6]).
- The complaint alleges Merit Medical acquired the HeRO Graft from CryoLife Inc. for $18.5 million and that it has been implanted by over 300 physicians, suggesting its market presence (Compl. ¶[p. 2]).
- No probative visual evidence provided in complaint.
IV. Analysis of Infringement Allegations
The infringement theory is articulated as literal infringement under 35 U.S.C. § 112, para. 6, arguing that the accused device contains structures that are the same as or equivalent to the structures disclosed in the patent corresponding to the claimed "means."
U.S. Patent No. 8,747,344 Infringement Allegations
| Claim Element (from Independent Claim 13) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| an arteriovenous shunt means comprising: | The HeRO Graft as a whole system is alleged to be an arteriovenous shunt means. | ¶[p. 9] | col. 4:28-30 |
| i. an arterial graft means comprising a body, a lead end and a terminal end... | The HeRO Graft’s arterial graft component, alleged to be 6 mm in diameter. | ¶[p. 5, 9] | col. 4:30-46 |
| ii. a-single lumen venous outflow catheter means... operable for insertion through a vein into the right atrium of the heart... | The HeRO Graft’s venous outflow catheter, alleged to be 5 mm in diameter and positioned in the right atrium. | ¶[p. 5, 9] | col. 4:47-60 |
| iii. a cuff means... wherein: 1. said cuff is disposed about said terminal end of said subcutaneous graft; and 2. said cuff is disposed about said intake end of said venous outflow catheter... | The HeRO Graft’s "metallic connector," which connects the arterial graft and venous outflow catheter. The complaint concedes a structural difference (disposed "in" versus "about") but alleges this is insubstantial. | ¶[p. 5, 10] | col. 4:60-68 |
| b. a hemodialysis apparatus. | The complaint alleges the hemodialysis function of the HeRO Graft is identical to that of the claimed invention. | ¶[p. 6, 9] | col. 6:22-35 |
- Identified Points of Contention:
- Scope Questions: The central dispute appears to be whether the HeRO Graft's "metallic connector," which is described as being "disposed in, connecting the arterial graft and venous outflow catheter," can be considered a structural equivalent to the claimed "cuff means," which is explicitly limited in the claim language as being "disposed about" the graft and catheter (Compl. ¶5; ’344 Patent, col. 8:31-34).
- Technical Questions: A key question for the court will be whether the structural difference between an internal connector (as alleged for the HeRO Graft) and an external sleeve-like cuff (as described and claimed in the patent) is "insubstantial," as the plaintiff alleges (Compl. ¶[p. 5]). The analysis under § 112, para. 6 requires an assessment of whether the accused structure performs the identical function in substantially the same way to achieve substantially the same result.
V. Key Claim Terms for Construction
The construction of the means-plus-function terms will be dispositive. The most contentious term appears to be "cuff means."
- The Term: "a cuff means comprising an inlet and an outlet, wherein... said cuff is disposed about said terminal end of said subcutaneous graft; and... said cuff is disposed about said intake end of said venous outflow catheter"
- Context and Importance: This term is critical because the plaintiff acknowledges a structural difference between the disclosed embodiment and the accused product's connector (Compl. ¶[p. 5]). The infringement case hinges on whether the accused "metallic connector" is a structural equivalent under § 112, para. 6. Practitioners may focus on whether the "disposed about" language is a strict structural limitation or merely descriptive of one possible embodiment.
- Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: A party might argue that the primary function of the "cuff means" is simply "connecting the graft and the venous outflow catheter" and providing a "secure fit" (’344 Patent, col. 4:60-62; col. 8:35-38). The complaint advances this view, arguing that because the function is identical, the structural difference is "insubstantial" (Compl. ¶[p. 5]).
- Evidence for a Narrower Interpretation: The claim language itself explicitly recites that the cuff is "disposed about" the graft and catheter (’344 Patent, col. 8:31-34). The specification describes the cuff as a structure over which surgical anastomosis occurs, and Figure 1 depicts the cuff (13) as an external sleeve connecting the graft (11) and catheter (12) (’344 Patent, Fig. 1; col. 4:60-68). This evidence may support a narrower construction where the corresponding structure must be an external component.
VI. Other Allegations
- Indirect Infringement: The complaint alleges induced infringement under 35 U.S.C. § 271(b), asserting that Merit Medical sells the component parts of the HeRO Graft to hospitals, thereby encouraging physicians to assemble and implant the device in an infringing manner (Compl. ¶[p. 13]).
- Willful Infringement: Willfulness is alleged based on "Intentional Copying" (Compl. ¶[p. 13]). The complaint asserts that Merit Medical "willfully copied the plaintiffs' venous outflow catheter" concept of depositing blood into the right atrium, distinguishing it from prior art devices where the catheter remained in a vein (Compl. ¶[p. 14]). The prior litigation between the parties would also serve as a basis for alleging knowledge of the patent.
VII. Analyst’s Conclusion: Key Questions for the Case
- A central issue will be one of structural equivalence: under the framework of 35 U.S.C. § 112, para. 6, can the HeRO Graft’s internal "metallic connector" be considered legally equivalent to the claimed "cuff means," which the patent’s claim language and figures appear to limit to an external structure "disposed about" the components it connects?
- A secondary question will be one of procedural effect: what, if any, preclusive effect does the prior lawsuit's dismissal with prejudice on venue grounds have on the current litigation? While a dismissal for improper venue typically does not preclude a new suit in a proper forum, the "with prejudice" designation may become a point of legal argument.
- An evidentiary question will be one of intent: what evidence exists to support the allegation of "intentional copying" for willfulness, beyond the observation that both the patented invention and the accused product deposit blood in the right atrium?