DCT
1:25-cv-00592
Treace Medical Concepts Inc v. Zimmer Biomet Holdings Inc
Key Events
Amended Complaint
I. Executive Summary and Procedural Information
- Parties & Counsel:
- Plaintiff: Treace Medical Concepts, Inc. (Delaware)
- Defendant: Zimmer Biomet Holdings, Inc. (Delaware) and Paragon 28, Inc. (Delaware)
- Plaintiff’s Counsel: Heyman Enerio Gattuso & Hirzel LLP (Lead Counsel); Winston & Strawn LLP (Of Counsel)
- Case Identification: 1:25-cv-00592, D. Del., 08/13/2025
- Venue Allegations: Venue is asserted based on Defendants being Delaware corporations and allegedly conducting business within the judicial district.
- Core Dispute: Plaintiff alleges that Defendants’ Bun-Yo-Matic™ Lapidus Clamp System, an instrumented surgical kit, and the associated surgical methods infringe five U.S. patents related to the correction of bunion deformities.
- Technical Context: The technology concerns orthopedic surgical systems—including instruments, implants, and methods—designed to correct complex, three-dimensional misalignments of foot bones that cause bunions.
- Key Procedural History: Plaintiff Treace Medical alleges it created the market for instrumented tarsometatarsal (TMT) bunion correction. Defendant Paragon 28 launched the accused Bun-Yo-Matic™ system in January 2024 and was subsequently acquired by Defendant Zimmer Biomet in April 2025. The complaint alleges Defendants had pre-suit knowledge of Treace's patent portfolio through public announcements and industry presence. This filing is an Amended Complaint, following an original complaint.
Case Timeline
| Date | Event |
|---|---|
| 2014-07-15 | ’941 Patent Priority Date |
| 2015-01-07 | ’397 Patent Priority Date |
| 2015-07-14 | ’368 Patent Priority Date |
| 2015-08-14 | ’428 and ’481 Patent Priority Date |
| 2015-01-01 | Plaintiff launches Lapiplasty® System (approx. date) |
| 2021-01-01 | Plaintiff launches Lapiplasty Mini-Incision® System (approx. date) |
| 2024-01-01 | Defendant Paragon 28 launches accused Bun-Yo-Matic™ System (approx. date) |
| 2024-01-01 | Plaintiff launches Micro-Lapiplasty® System (approx. date) |
| 2024-10-01 | ’368 Patent Issues |
| 2025-04-08 | ’397 Patent Issues |
| 2025-04-08 | ’428 Patent Issues |
| 2025-04-15 | ’481 Patent Issues |
| 2025-04-21 | Defendant Zimmer Biomet acquires Defendant Paragon 28 |
| 2025-07-08 | ’941 Patent Issues |
| 2025-08-13 | Complaint Filing Date |
II. Technology and Patent(s)-in-Suit Analysis
U.S. Patent No. 12,102,368 - Bone Positioning Guide
The Invention Explained
- Problem Addressed: The patent’s background section notes that manual realignment of bones by a surgeon can be complex and lead to "inconsistent treatment results" (’368 Patent, col. 1:33-42). Traditional approaches are described as surgically difficult, "freehand" techniques that produce mixed results (Compl. ¶¶18-19).
- The Patented Solution: The invention is a C-clamp-like bone positioning guide that engages a first bone (e.g., the first metatarsal) with a movable "bone engagement member" and a second bone (e.g., the second metatarsal) with a stationary "tip." Actuating the guide moves the first bone relative to the second, allowing a surgeon to correct misalignment in three anatomical planes—transverse, sagittal, and frontal—simultaneously. The guide then holds the bones in the corrected orientation for surgical fixation (’368 Patent, col. 2:4-24). A diagram from the patent family, included in the complaint, illustrates this multi-planar correction capability (Compl. ¶26, p. 9).
- Technical Importance: The instrumented approach allows surgeons to achieve a reproducible, three-dimensional correction of the foot's biomechanical structure, addressing the root cause of the bunion deformity (Compl. ¶21).
Key Claims at a Glance
- The complaint asserts at least independent claim 1 (Compl. ¶71).
- Claim 1 is a system claim comprising three essential elements:
- A bone preparation guide with a guide surface for a tissue removing instrument.
- A bone positioning guide configured to move a first metatarsal in a transverse plane (to reduce the intermetatarsal angle) and rotate the first metatarsal in a frontal plane.
- At least one fixation device (e.g., a plate or screw) for fixating the moved position of the first metatarsal relative to the medial cuneiform for fusion.
- The complaint does not explicitly reserve the right to assert dependent claims for this patent.
U.S. Patent No. 12,268,397 - Bone Cutting Guide Systems and Methods
The Invention Explained
- Problem Addressed: The patent addresses the general need for accurately positioning and cutting bones during orthopedic surgery, particularly in complex joints like the foot (’397 Patent, Background). Traditional "freehand" cutting techniques can result in inconsistent outcomes (Compl. ¶19).
- The Patented Solution: The invention is a bunion correction method that uses a system of guides to ensure precise bone cuts. The method involves attaching a first cutting guide to the metatarsal using fixation pins, making a cut, adjusting the metatarsal's alignment, and then positioning a second cutting guide over the cuneiform—using the same fixation pins as a reference—to make a corresponding cut. This sequence ensures the resulting bone surfaces are properly aligned for fusion after the correction has been made (’397 Patent, Claim 1). The complaint includes a visual of a cut guide being used to perform precision cuts (Compl. ¶29, p. 11).
- Technical Importance: This instrumented method provides a way to make precise, co-planar bone cuts across a joint after the bones have been moved into their corrected anatomical position, which is critical for achieving stable fusion (Compl. ¶¶30, 54).
Key Claims at a Glance
- The complaint asserts at least independent claim 1 (Compl. ¶103).
- Claim 1 is a method claim with several key steps:
- Inserting a cutting member through a first bone cutting guide slot to cut a portion of the metatarsal.
- Adjusting the alignment of the metatarsal relative to a cuneiform.
- Positioning a second bone cutting guide slot over the cuneiform, where the second guide is attached to the metatarsal via at least the fixation pins used for the first guide.
- Inserting the cutting member through the second cutting slot to cut the cuneiform.
- Causing the metatarsal to fuse to the cuneiform in the new, moved position.
- The complaint does not explicitly reserve the right to assert dependent claims for this patent.
U.S. Patent No. 12,268,428 - Tarsal-Metatarsal Joint Procedure Utilizing Fulcrum
- Technology Synopsis: The patent describes an instrumented surgical technique for treating a bunion deformity. The method involves inserting an instrument, or "fulcrum," between the first and second metatarsals and then moving the first metatarsal so that it pivots about the fulcrum, thereby correcting its alignment before fusion (’428 Patent, Abstract; Claim 1).
- Asserted Claims: At least independent claim 1 (Compl. ¶138).
- Accused Features: The surgical procedure for bunion correction that is allegedly taught and encouraged by Defendants through their "Bun-Yo-Matic Guide and Bun-Yo-Matic Videos" (Compl. ¶137).
U.S. Patent No. 12,274,481 - Bone Positioning and Preparing Guide Systems and Methods
- Technology Synopsis: The patent claims an instrumented surgical technique for repositioning a first metatarsal. The method includes engaging both the first and second metatarsals with a bone positioning guide, rotating a knob on the guide to reduce the angle between them, and imparting a force to a pin to adjust the rotational alignment of the first metatarsal (’481 Patent, Claim 1).
- Asserted Claims: At least independent claim 1 (Compl. ¶173).
- Accused Features: The surgical procedure allegedly instructed by Defendants through their Bun-Yo-Matic System's instructional guides and videos (Compl. ¶172).
U.S. Patent No. 12,349,941 - Bone Positioning and Cutting System and Method
- Technology Synopsis: The patent describes a method of correcting an alignment between a first metatarsal and a first cuneiform. It involves using a positioning device having a multi-axis joint that connects two blocks, which are attached to the respective bones via fixation pins. The device is manipulated to align the bones and then locked in place with a set screw before the bones are prepared for fusion (’941 Patent, Abstract).
- Asserted Claims: At least independent claim 1 (Compl. ¶208).
- Accused Features: The surgical method for bunion correction that is allegedly taught by Defendants using the Bun-Yo-Matic system (Compl. ¶207).
III. The Accused Instrumentality
Product Identification
The Bun-Yo-Matic™ Lapidus Clamp System ("Bun-Yo-Matic System") (Compl. ¶39). The infringement allegations also target the surgical methods taught by Defendants for use with this system (Compl. ¶¶43, 51).
Functionality and Market Context
The Bun-Yo-Matic System is a set of surgical instruments marketed for bunion correction procedures (Compl. ¶42). Its advertised purpose is to assist with "de-rotation, IM angle reduction, and joint closure" during a Lapidus arthrodesis (a type of fusion surgery) (Compl. ¶53). The system is promoted as including "cutting guides designed to remove minimal bone... to prepare the joint for fusion" and to "help establish parallel cut surfaces" (Compl. ¶54). The complaint alleges this system is an "unauthorized copycat version" of Plaintiff's Lapiplasty® System, which created the market for instrumented bunion correction (Compl. ¶¶39, 51). The complaint provides a visual from the patent family showing how Plaintiff's system corrects misalignment in the transverse, sagittal, and frontal planes (Compl. ¶21, p. 6).
IV. Analysis of Infringement Allegations
The complaint references claim chart exhibits for the asserted patents but does not attach them. The following summaries are based on the narrative allegations.
U.S. Patent No. 12,102,368
Infringement Allegations
| Claim Element (from Independent Claim 1) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| a metatarsal bunion correction system comprising: a bone preparation guide comprising a body defining a guide surface... | The Bun-Yo-Matic System is alleged to be a metatarsal bunion correction system that includes cutting guides for preparing bone surfaces for fusion. | ¶¶45, 54, 70 | col. 7:5-15 |
| a bone positioning guide configured to move the first metatarsal... in a transverse plane... and rotating the first metatarsal in a frontal plane; | The Bun-Yo-Matic System's clamp and associated procedure are alleged to assist with "IM angle reduction" (transverse plane) and "de-rotation" (frontal plane). | ¶¶53, 70 | col. 6:15-24 |
| and at least one fixation device positionable across a tarsal-metatarsal joint... to fixate a moved position of the first metatarsal... for fusion. | The Bun-Yo-Matic System is promoted for use with fixation devices such as the "Paragon 28 Gorilla® Lapidus Plate" to permanently fix the corrected bone position for fusion. | ¶53 | col. 8:56-61 |
Identified Points of Contention
- Scope Questions: Claim 1 recites a "system" comprising three distinct components (preparation guide, positioning guide, fixation device). A central question may be whether Defendants' Bun-Yo-Matic System, as sold or offered for sale, constitutes the complete claimed system, particularly if the fixation devices are marketed as compatible but sold separately.
- Technical Questions: The complaint alleges the accused system assists with "de-rotation" and "IM angle reduction" (Compl. ¶53). A key technical question will be what evidence demonstrates that the accused Bun-Yo-Matic clamp, by its mechanical operation, performs the specific dual functions of both moving the metatarsal in the transverse plane and rotating it in the frontal plane, as required by the claim.
U.S. Patent No. 12,268,397
Infringement Allegations
| Claim Element (from Independent Claim 1) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| inserting a cutting member through the first bone cutting guide slot to cut the portion of the metatarsal; | Defendants' instructional materials allegedly teach using the Bun-Yo-Matic system's cutting guides to cut the metatarsal bone. | ¶¶54, 102 | col. 11:47-51 |
| adjusting an alignment of the metatarsal relative to a cuneiform to establish a moved position... | The accused surgical method allegedly involves realigning the metatarsal to correct the bunion deformity after the initial cut. | ¶¶53, 102 | col. 11:25-34 |
| positioning a second bone cutting guide slot over a portion of the cuneiform..., the second bone cutting guide slot being attached to the metatarsal by at least the first fixation pin... and the second fixation pin... | The complaint's allegations suggest that the method taught by Defendants involves using a guide system to make coordinated cuts on both the metatarsal and cuneiform. | ¶102 | col. 11:52-60 |
| inserting the cutting member through the second cutting slot to cut the portion of the cuneiform; | The accused method allegedly includes using the system's guides to make a corresponding cut on the cuneiform bone to create parallel surfaces for fusion. | ¶¶54, 102 | col. 11:61-63 |
Identified Points of Contention
- Technical Questions: A primary question will be evidentiary: does the surgical technique taught by Defendants' "Bun-Yo-Matic Guide and Bun-Yo-Matic Videos" (Compl. ¶102) require surgeons to perform the highly specific step of attaching the cuneiform cutting guide to the metatarsal using the same fixation pins that were used for the metatarsal cut? Proving this precise sequence of operations will be central to the infringement analysis.
- Scope Questions: The infringement allegation is against the performance of a method. A question for the court will be whether the general instructions to create "parallel cut surfaces" (Compl. ¶54) are sufficient to encourage or require surgeons to perform the specific, ordered sequence of steps recited in Claim 1.
V. Key Claim Terms for Construction
U.S. Patent No. 12,102,368
- The Term: "bone positioning guide configured to... move the first metatarsal... in a transverse plane... and rotating the first metatarsal in a frontal plane"
- Context and Importance: This term defines the core functionality of the key component in the system claim. The infringement analysis will depend on whether the accused clamp is proven to perform both the lateral "move" (transverse plane correction) and the axial "rotation" (frontal plane correction). Practitioners may focus on whether these two distinct corrective actions must be performed simultaneously or as the result of a single user action.
- Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The specification states that as the guide's engagement member is advanced, "the position of the first metatarsal may be realigned in three planes" (’368 Patent, col. 2:14-17). This language suggests the multi-planar correction is an outcome of the guide's general operation, not necessarily requiring separate, independent mechanisms for each plane of motion.
- Evidence for a Narrower Interpretation: Claim 1 explicitly lists "moving" in one plane "and rotating" in another as distinct functions of the guide. The specification describes how actuation of the device "rotates with the first metatarsal... as it pushes the first metatarsal laterally" (’368 Patent, col. 10:1-4), which could be interpreted to require a specific mechanism that couples these two motions.
U.S. Patent No. 12,268,397
- The Term: "the second bone cutting guide slot being attached to the metatarsal by at least the first fixation pin inserted into the metatarsal and the second fixation pin inserted into the metatarsal"
- Context and Importance: This limitation is critical because it defines the structural relationship that ensures the cut on the cuneiform is precisely aligned relative to the cut on the metatarsal. Infringement will likely hinge on whether the accused method teaches this specific manner of using the same fixation hardware as a common reference for both cuts.
- Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: A defendant might argue that "attached to" could mean indirectly attached or merely referenced. However, the claim's recitation of specific pins makes this a difficult position.
- Evidence for a Narrower Interpretation: The plain language strongly suggests a direct physical connection. The patent describes a system where a support is fixed to a bone via pins, and a guide member slides along a shaft on that support, reinforcing the concept of a shared, fixed reference frame for sequential cuts (’397 Patent, col. 2:38-44).
VI. Other Allegations
- Indirect Infringement: The complaint alleges both induced and contributory infringement for all five patents. The inducement theory is based on allegations that Defendants provide instructional materials, including the "Bun-Yo-Matic Guide" and "Bun-Yo-Matic Videos," as well as sales representatives who instruct and encourage surgeons to use the accused system in a manner that directly infringes the patent claims (Compl. ¶¶73-74, 80, 109-110). Contributory infringement is alleged on the basis that components of the Bun-Yo-Matic System are not staple articles of commerce and are especially made for the infringing use (Compl. ¶¶82, 87).
- Willful Infringement: Willfulness is alleged for all five patents based on alleged pre-suit knowledge of Treace's patent rights. The complaint asserts this knowledge arises from Treace's virtual patent marking webpage, public press releases announcing its patents, its status as the pioneer of the instrumented TMT bunion correction market, and its participation at industry conferences attended by Defendants (Compl. ¶¶60-65, 91-94).
VII. Analyst’s Conclusion: Key Questions for the Case
- A core issue will be one of evidentiary mapping: For the system patent ('368), can Plaintiff demonstrate that the collection of instruments sold or promoted by Defendants constitutes the complete claimed "system"? For the four method patents, can Plaintiff prove, on a limitation-by-limitation basis, that the surgical technique actually taught by Defendants and performed by surgeons is the same as the specific, multi-step sequences recited in each of the asserted claims?
- A second central question will be one of technical specificity: The asserted patents claim distinct methods and systems for achieving a three-dimensional bunion correction (e.g., via a C-clamp, a specific cutting guide sequence, a fulcrum). The case will likely turn on whether the accused Bun-Yo-Matic System's single mechanism of action can be shown to simultaneously practice the unique technical requirements of each of these different patented inventions, or if its operation is fundamentally distinct from one or more of them.
- A final key question will be one of infringement allocation: With five patents asserted against a single product and surgical technique, the analysis may focus on whether the accused conduct constitutes infringement of all five distinct inventions, or if the infringement, if any, is limited to a subset of the asserted claims, raising questions about potential overlap or redundancy in the infringement theories.