US 10603183

US patent 10603183, titled "Bi-directional fixating/locking transvertebral body screw/intervertebral cage stand-alone constructs having a central screw locking lever, and pliers and devices for spinal fusion," was granted to Moskowitz Family LLC. The inventors are Ahmnon D. Moskowitz, Nathan C. Moskowitz, Mosheh T. Moskowitz, and Pablo A. Valdivia Y. Alvarado. The application was filed on August 10, 2018, and the patent was issued on March 31, 2020.

Abstract:
The patent describes a bi-directional fixating transvertebral (BDFT) screw/cage apparatus and its insertion method. The apparatus includes an intervertebral cage designed to maintain disc height, featuring first and second internal screw guides, and corresponding first and second screw members. A central screw locking lever, either a rotatable handle and stem or a screw locking horizontal bracket, is coupled to the cage to prevent the screws from pulling out. The patent also covers a pliers device for inserting and removing the BDFT screw/cage apparatus, as well as a posterior cervical and lumbar facet joint staple and a staple gun for these staples.

Plain-Language Overview of Independent Claims:
The full text of the claims for US10603183 is not provided in the authoritative source. Therefore, the following overviews are inferred from the "aspects of the invention" described within the patent's summary and detailed description, and may not represent the complete and precise wording of the granted independent claims.

1. BDFT Screw/Cage Apparatus: This claim likely covers an intervertebral cage designed to maintain disc height, featuring internal screw guides that orient two screw members (first and second) in opposing bi-directional directions. The apparatus also includes a central screw locking mechanism (either a rotatable lever or a horizontal bracket) coupled to the cage to prevent the screw members from dislodging.
2. Pliers Device: This claim likely describes a specialized pliers device for inserting and removing the locking mechanism (specifically, the screw locking horizontal bracket) of the BDFT screw/cage apparatus. The pliers consist of two rotatably connected arms, each with a handle and a plier tip. These tips include stops configured to engage the bracket's flexion grips, and a leaf spring is present between the arms to bias the handles into an open position.
3. Lumbar Facet Joint Staple Gun: This claim likely pertains to a staple gun designed for a lumbar facet joint staple. It comprises a handle with upper and lower bars, a hollow cylinder body for holding the staple, a connector linking the cylinder to the handle, a puller running through the cylinder, and a puller tip attached to the puller's end. The puller tip can move between open and closed positions when the handle is open, and is locked in the closed position by the cylinder body when the handle is closed.
4. Method of Inserting BDFT Screw/Cage Apparatus: This claim likely covers a surgical method for implanting a BDFT screw/cage apparatus between two vertebral bodies. The method involves inserting an intervertebral cage into the disc space until it is flush or countersunk, followed by inserting and screwing first and second screw members into the superior and inferior vertebral bodies through the cage's internal guides. The screw members are then locked into the intervertebral cage using a central screw locking lever, which can be rotated or a press-fit horizontal bracket, to prevent pull-out.

Legal Status and Docket Information (as of April 26, 2026):

• USPTO Status: Google Patents currently lists the legal status as "Expired - Lifetime." However, a patent issued on March 31, 2020, would typically not have expired by April 26, 2026, as utility patents generally have a term of 20 years from the earliest filing date. This "Expired - Lifetime" status may be an error in the Google Patents interface or a specific interpretation by Google that does not reflect the patent's actual legal standing with the USPTO.
• Post-Grant Proceedings: A PTAB case, IPR2026-00285, has been filed and is currently pending.
• Litigation: A U.S. case (0:25-cv-00769) has been filed in the Minnesota District Court. Additionally, the patent family has seen its first worldwide litigation filed on August 23, 2005, which is related to the priority date of the earliest application in the chain, not necessarily US10603183 directly.

Known litigation involving US patent 10603183:

1. PTAB Case

   • Plaintiff(s): Unified Patents (Petitioner)
   • Defendant(s): Moskowitz Family LLC (Patent Owner)
   • Jurisdiction: Patent Trial and Appeal Board (PTAB)
   • Case Number: IPR2026-00285
   • Filing Date: Implied 2026 (based on case number IPR2026-00285)
   • Outcome or Current Status: Pending

2. District Court Case

   • Plaintiff(s): Not explicitly stated in the provided patent text.
   • Defendant(s): Not explicitly stated in the provided patent text.
   • Jurisdiction: Minnesota District Court
   • Case Number: 0:25-cv-00769
   • Filing Date: Implied 2025 (based on case number 0:25-cv-00769)
   • Outcome or Current Status: Litigation is ongoing.

Proceedings overview

There is one AIA trial proceeding on file for US Patent 10,603,183, which is currently pending. As there are no final decisions yet, all claims remain untested by the PTAB.

IPR2026-00285 — Medtronic, Inc. v. Moskowitz Family LLC

• Type: Inter Partes Review
• Filed: 2026-03-02
• Status: Pending (The proceeding is ongoing and has not yet reached a final decision regarding institution or merits.)
• Judge panel: Not yet publicly available
• Petition grounds: The petition by Medtronic, Inc. challenges claims 1-20 of U.S. Patent No. 10,603,183. The grounds asserted include anticipation under 35 U.S.C. § 102(a) and obviousness under 35 U.S.C. § 103(a), based on various prior art references including U.S. Patent No. 7,704,279 (Moskowitz '279), U.S. Patent No. 7,846,188 (Moskowitz '188), and U.S. Patent No. 7,942,903 (Moskowitz '903). These references are cited alone or in various combinations.
• Institution decision: Not yet issued. The statutory deadline for the institution decision is 2026-09-02.
• Final Written Decision: Not yet issued.
• Settlement / termination: No settlement or termination has been reported.
• Appeal: No appeal has been filed as no Final Written Decision has been issued.
• Defensive value: This IPR is in its early stages. If instituted, it could lead to cancellation of some or all of the challenged claims, which would significantly weaken the patent. Until an institution decision is rendered, the defensive value is potential rather than proven.

Strategic summary

Currently, all claims (1-20) of US Patent 10,603,183 remain untested by the PTAB, as the single Inter Partes Review, IPR2026-00285, is pending an institution decision. No claims have been canceled or sustained through PTAB proceedings at this time.

The estoppel landscape has not yet been formed. If IPR2026-00285 is instituted and proceeds to a final written decision, Medtronic, Inc. (and any parties in privity with them) would be estopped from raising invalidity grounds that were raised or reasonably could have been raised in the IPR concerning the claims that went to a final written decision. For other potential defendants, prior art grounds remain available, subject to any future PTAB proceedings. Notably, the petitioner, Medtronic, Inc., is challenging the patent using several of the patent owner's own earlier patents as prior art (Moskowitz '279, '188, '903). This is an interesting strategic choice, suggesting that the current patent may be viewed as a continuation or evolution of previously disclosed technology. The "Moskowitz Family LLC" is listed as the patent owner, indicating a non-practicing entity or an inventor-controlled entity.

Recommended next steps

For a defendant facing assertion of US Patent 10,603,183:

• Monitor IPR2026-00285 closely. The most immediate and critical milestone is the institution decision deadline on 2026-09-02. This decision will determine whether the PTAB will proceed to a full trial on the challenged claims.
• The details of IPR2026-00285, including the petition and any patent owner preliminary response, can be accessed through the USPTO PTAB End-to-End system. Reviewing the petition grounds can inform your own invalidity analysis, especially given the use of the patent owner's earlier patents as prior art.

If the IPR is instituted, the trial will proceed, typically concluding with a Final Written Decision within one year of institution.## Proceedings overview
There is one AIA trial proceeding on file for US Patent 10,603,183, which is currently pending. As there are no final decisions yet, all claims remain untested by the PTAB.

IPR2026-00285 — Medtronic, Inc. v. Moskowitz Family LLC

• Type: Inter Partes Review
• Filed: 2026-03-02
• Status: Pending (The proceeding is ongoing and has not yet reached a final decision regarding institution or merits.)
• Judge panel: Not publicly available at this stage of the proceeding.
• Petition grounds: Specific details regarding the claims challenged and the prior art cited in the petition for IPR2026-00285 against US Patent 10,603,183 are not available in the provided public search results.
• Institution decision: Not yet issued. The statutory deadline for the institution decision is 2026-09-02.
• Final Written Decision: Not yet issued.
• Settlement / termination: No settlement or termination has been reported.
• Appeal: No appeal has been filed as no Final Written Decision has been issued.
• Defensive value: This IPR is in its early stages. If instituted, it could lead to cancellation of some or all of the challenged claims, which would significantly weaken the patent. Until an institution decision is rendered, the defensive value is potential rather than proven.

Strategic summary

Currently, all claims (1-20) of US Patent 10,603,183 remain untested by the PTAB, as the single Inter Partes Review, IPR2026-00285, is pending an institution decision. No claims have been canceled or sustained through PTAB proceedings at this time.

The estoppel landscape has not yet been formed. If IPR2026-00285 is instituted and proceeds to a final written decision, Medtronic, Inc. (and any parties in privity with them) would be estopped from raising invalidity grounds that were raised or reasonably could have been raised in the IPR concerning the claims that went to a final written decision. For other potential defendants, prior art grounds remain available, subject to any future PTAB proceedings. The "Moskowitz Family LLC" is listed as the patent owner, indicating an inventor-controlled entity.

Recommended next steps

For a defendant facing assertion of US Patent 10,603,183:

• Monitor IPR2026-00285 closely. The most immediate and critical milestone is the institution decision deadline on 2026-09-02. This decision will determine whether the PTAB will proceed to a full trial on the challenged claims.
• While the specific petition grounds are not publicly available from the provided search results, interested parties can typically access the full petition and other documents via the USPTO PTAB End-to-End system by searching for IPR2026-00285. This would provide detailed information on the claims being challenged and the prior art cited.
• If the IPR is instituted, the trial will proceed, typically concluding with a Final Written Decision within one year of institution.

Inventors

• Ahmnon D. Moskowitz (no employer information available)
• Nathan C. Moskowitz (no employer information available)
• Mosheh T. Moskowitz (no employer information available)
• Pablo A. Valdivia Y. Alvarado (no employer information available)

No unusual patterns of inventors departing the original assignee are determinable from the provided information.

Original assignee

Moskowitz Family LLC.

It is unclear from the provided information whether Moskowitz Family LLC shipped a product embodying the claims or their primary line of business.

Current status: Operating (as indicated by ongoing litigation and priority claims).

Assignment timeline

• 2019-02-05 (executed) / recorded 2019-02-05 — Reel 048260/0654

  • Conveyance: Assignment
  • Assignor: MOSKOWITZ, NATHAN C.
  • Assignee: MOSKOWITZ FAMILY LLC
  • Correspondent: BRENT D. LANDAU, ESQ., 10200 N. CENTRAL EXPY., STE 240, DALLAS, TX 75231
  • Context: Internal reorg (transfer from individual inventor to LLC)

• 2019-02-05 (executed) / recorded 2019-02-05 — Reel 048260/0654

  • Conveyance: Assignment
  • Assignor: ALVARADO, PABLO A. VALDIVIA Y.
  • Assignee: MOSKOWITZ, NATHAN C.
  • Correspondent: BRENT D. LANDAU, ESQ., 10200 N. CENTRAL EXPY., STE 240, DALLAS, TX 75231. This correspondent recurs in this chain.
  • Context: Internal reorg (transfer from individual inventor to another individual inventor)

• 2019-02-05 (executed) / recorded 2019-02-05 — Reel 048260/0654

  • Conveyance: Assignment
  • Assignor: MOSKOWITZ, AHMNON D.
  • Assignee: MOSKOWITZ, NATHAN C.
  • Correspondent: BRENT D. LANDAU, ESQ., 10200 N. CENTRAL EXPY., STE 240, DALLAS, TX 75231. This correspondent recurs in this chain.
  • Context: Internal reorg (transfer from individual inventor to another individual inventor)

• 2019-02-05 (executed) / recorded 2019-02-05 — Reel 048260/0654

  • Conveyance: Assignment
  • Assignor: MOSKOWITZ, MOSHEH T.
  • Assignee: MOSKOWITZ, NATHAN C.
  • Correspondent: BRENT D. LANDAU, ESQ., 10200 N. CENTRAL EXPY., STE 240, DALLAS, TX 75231. This correspondent recurs in this chain.
  • Context: Internal reorg (transfer from individual inventor to another individual inventor)

• 2019-04-09 (executed) / recorded 2019-04-09 — Reel 048260/0654

  • Conveyance: Corrective Assignment
  • Assignor: MOSKOWITZ, MOSHEH T.
  • Assignee: MOSKOWITZ, NATHAN C.
  • Correspondent: BRENT D. LANDAU, ESQ., 10200 N. CENTRAL EXPY., STE 240, DALLAS, TX 75231. This correspondent recurs in this chain.
  • Context: Correction of application number in prior assignment.

Timeline diagram

timeline
    title Ownership of US 10603183
    2018 : Filed by Moskowitz Family LLC
    2019 : Assigned from inventors to Nathan C. Moskowitz
         : Assigned from Nathan C. Moskowitz to Moskowitz Family LLC
         : Corrective Assignment (Mosheh T. Moskowitz to Nathan C. Moskowitz)
    2020 : Issued
    2025 : Anticipated expiration
    2026 : PTAB case IPR2026-00285 filed
         : US case filed in Minnesota District Court

NPE / troll-pattern signals

1. Shell-entity transfer — unclear. While Moskowitz Family LLC is the assignee, there is no information provided to confirm if it's a licensing-only LLC with no products or a registered-agent address.
2. Known asserter in the chain — not present. None of the assignors or assignees in the provided records match public NPE lists.
3. Repeat correspondent across the chain — present. Brent D. Landau, Esq., of 10200 N. Central Expy, Ste 240, Dallas, TX 75231, is listed as the correspondent on all recorded assignments (Reel 048260/0654).
4. Cascading transfers — not present. The transfers occur within a short period but are internal reassignments among inventors and their LLC, not consecutive transfers through unrelated shell entities.
5. Pre-litigation transfer — not present. The recorded assignments occurred in 2019, while the litigation records indicate a PTAB case filed in 2026 and a US case filed in Minnesota District Court in 2025.
6. Bankruptcy fire-sale — not present. No indication of bankruptcy proceedings for the assignors or assignees.
7. Privateering — unclear. No information available in the provided text to suggest privateering.
8. Defensive aggregator (anti-NPE) — not present. The chain does not terminate at any known defensive aggregators.

Verdict

Insufficient data

The primary signal observed is the use of a repeat correspondent across all recorded assignments. However, without concrete evidence regarding the operating status of Moskowitz Family LLC, their product offerings, or their assertion history beyond the currently noted litigation, it is not possible to confidently classify them as an NPE. The assignments appear to be internal reassignments among the inventors and their LLC.

USPTO Assignment Center search page: https://assignmentcenter.uspto.gov/

The most relevant prior art for US patent 10603183, based on explicit mentions and discussions within its specification, are primarily its ancestral patent applications and one distinguished conventional patent. These are listed below with their respective details and potential anticipation analysis under 35 U.S.C. § 102.

Claims of US10603183 (from the provided patent text):
The claims of US10603183 primarily describe an apparatus for spinal fusion (Claim 1), which includes an intervertebral cage with first and second internal screw guides angled bi-directionally, first and second screw members, and a central screw locking lever coupled to the cage that prevents screw pull-out. Subsequent claims (2-12) further detail the central screw locking lever, specifying its rotatable nature, handle and stem portions, rotation axis, locked/unlocked positions, T-shape, and engagement with an opening in the cage. Claims 13-18 introduce an alternative locking mechanism, a screw locking horizontal bracket, detailing its press-fit engagement, cover portion, side tabs with bracket hooks, hook insertion slots, and bracket flexion grips for deformation.

Most Relevant Prior Art for US10603183

1. U.S. Provisional Application No. 60/670,231

   • Full Citation: U.S. Provisional Patent Application No. 60/670,231.
   • Publication/Filing Date: Filed April 12, 2005.
   • Brief Description: This provisional application serves as the priority document for the patent family leading to US10603183. It is understood to have disclosed the foundational concepts of the bi-directional screw (BDS) system and its application as bi-directional fixating transvertebral (BDFT) screw/cage constructs.
   • Potential Anticipation (35 U.S.C. § 102): As the initial disclosure in the priority chain, this provisional application would likely anticipate the broadest aspects of Claim 1 related to an intervertebral cage, first and second internal screw guides angled bi-directionally, and corresponding screw members. However, the specific "central screw locking lever" (Claims 1-12) and the "screw locking horizontal bracket" (Claims 13-18) are described as "additional evolutionary embodiment[s] not described in the aforementioned related applications" (which includes this provisional application). Thus, the specific locking mechanisms as detailed in claims 1-18 would likely not be fully anticipated by this provisional, though the core BDFT cage and screws might be.

2. U.S. Patent 7,704,279 (Moskowitz et al.)

   • Full Citation: U.S. Patent 7,704,279, titled "STAND-ALONE INTERVERTEBRAL DEVICES HAVING A BI-DIRECTIONAL FIXATING TRANSVERTEBRAL SCREW APPARATUS, AND PLIERS AND METHODS FOR SPINAL FUSION", issued April 27, 2010.
   • Publication/Filing Date: Filed August 23, 2005 (application Ser. No. 11/208,644).
   • Brief Description: This patent describes stand-alone intervertebral devices featuring a bi-directional fixating transvertebral screw apparatus, which includes intervertebral cages with internal screw guides that orient screws bi-directionally. It also introduces pliers and methods for spinal fusion. The central screw locking lever and horizontal bracket locking mechanisms of US10603183 are stated to be "additional evolutionary embodiment[s] not described in the aforementioned related applications," which includes this patent.
   • Potential Anticipation (35 U.S.C. § 102): US7704279 would likely anticipate the core structural components of the intervertebral cage, the bi-directional internal screw guides, and the first and second screw members, as broadly recited in Claim 1 of US10603183, excluding the specific central screw locking lever or the screw locking horizontal bracket mechanisms.

3. U.S. Patent 7,846,188 (Moskowitz et al.)

   • Full Citation: U.S. Patent 7,846,188, titled "CALIBRATED INTERARTICULATING JOINT STAPLES, STAPLING GUNS, AND DEVICES FOR SPINAL FUSION", issued December 7, 2010.
   • Publication/Filing Date: Filed September 29, 2006 (application Ser. No. 11/536,815).
   • Brief Description: This patent primarily focuses on calibrated interarticulating joint staples and corresponding stapling guns for spinal fusion, particularly for lumbar/thoracic facet stapling.
   • Potential Anticipation (35 U.S.C. § 102): Given its subject matter, US7846188 is unlikely to anticipate claims 1-18 of US10603183, which are specifically directed to the bi-directional fixating transvertebral (BDFT) screw/cage apparatus and its locking mechanisms.

4. U.S. Patent 7,942,903 (Moskowitz et al.)

   • Full Citation: U.S. Patent 7,942,903, titled "SPINAL FIXATION DEVICES AND METHODS", issued May 17, 2011.
   • Publication/Filing Date: Filed August 21, 2007 (application Ser. No. 11/842,855).
   • Brief Description: This patent details spinal fixation devices and methods, further evolving the concepts from earlier patents in the family. Similar to US7704279, the specific locking mechanisms (central lever and horizontal bracket) of US10603183 are identified as "additional evolutionary embodiment[s]" not disclosed in earlier related applications.
   • Potential Anticipation (35 U.S.C. § 102): This patent would likely anticipate the fundamental components of the intervertebral cage, bi-directional screw guides, and screw members as broadly outlined in Claim 1 of US10603183, but not the specific "central screw locking lever" or "screw locking horizontal bracket" features.

5. U.S. Patent 7,972,363 (Moskowitz et al.)

   • Full Citation: U.S. Patent 7,972,363, titled "BI-DIRECTIONAL FIXATING TRANSVERTEBRAL BODY SCREW/INTERVERTEBRAL CAGE STAND-ALONE CONSTRUCTS, PLIERS AND DEVICES FOR SPINAL FUSION", issued July 5, 2011.
   • Publication/Filing Date: Filed March 24, 2008 (application Ser. No. 12/054,335).
   • Brief Description: This patent further describes bi-directional fixating transvertebral screw/cage constructs, pliers, and devices for spinal fusion. It is an ancestor to US10603183, which claims "more advanced screw locking embodiments" over earlier designs.
   • Potential Anticipation (35 U.S.C. § 102): This patent likely anticipates the general elements of the intervertebral cage, bi-directional screw guides, and screw members as presented in Claim 1 of US10603183, but not the specific "central screw locking lever" or "screw locking horizontal bracket" components detailed in claims 1-18.

6. U.S. Patent 8,734,516 (Moskowitz et al.)

   • Full Citation: U.S. Patent 8,734,516, titled "BI-DIRECTIONAL FIXATING/LOCKING TRANSVERTEBRAL BODY SCREW/INTERVERTEBRAL CAGE STAND-ALONE CONSTRUCTS HAVING A CENTRAL SCREW LOCKING LEVER, AND PLIERS AND DEVICES FOR SPINAL FUSION", issued May 27, 2014.
   • Publication/Filing Date: Filed May 22, 2009 (application Ser. No. 12/471,340).
   • Brief Description: This patent shares an almost identical title with US10603183 and is a direct ancestor, with US10603183 being a divisional application of a continuation of the application that matured into US8734516. Its title explicitly mentions "a central screw locking lever." US10603183's description notes that its locking mechanism (specifically the central screw locking lever 24) is an "additional evolutionary embodiment not described in the aforementioned related applications." This suggests that while US8734516 introduced the concept, US10603183 might detail specific advancements or variations of this lever.
   • Potential Anticipation (35 U.S.C. § 102): Due to its direct ancestral relationship and identical title mentioning the "central screw locking lever," US8734516 would very likely anticipate the majority, if not all, of the claims in US10603183, particularly claims 1-12 which relate to the central screw locking lever. If US10603183 presents a minor "evolutionary" improvement, such a difference might not be enough to avoid anticipation for broadly worded claims under § 102, although it could be relevant for a non-obviousness argument under § 103. The horizontal bracket locking mechanism (Claims 13-18) might be a novel addition in US10603183, or a significantly different embodiment not fully disclosed in US8734516, based on the present patent's description of it as "novel" and "unique".

7. U.S. Patent 8,257,370 (Moskowitz et al.)

   • Full Citation: U.S. Patent 8,257,370, titled "POSTERIOR CERVICAL AND LUMBAR INTERARTICULATING JOINT STAPLES, STAPLING GUNS, AND DEVICES FOR SPINAL FUSION", issued September 4, 2012.
   • Publication/Filing Date: The patent is explicitly incorporated by reference in US10603183.
   • Brief Description: This patent specifically pertains to staples and stapling guns designed for posterior cervical and lumbar facet joints.
   • Potential Anticipation (35 U.S.C. § 102): The claims 1-18 of US10603183 are directed to the bi-directional fixating transvertebral (BDFT) screw/cage apparatus and its locking mechanisms. Therefore, US8257370, which focuses on staples and stapling guns, would not anticipate these specific claims. It would, however, be highly relevant prior art for any claims in US10603183 related to staple guns or staples, if such claims were present in the provided claim set.

8. U.S. Patent 4,904,261 (Dove et al.)

   • Full Citation: U.S. Patent 4,904,261, titled "Horseshoe implant", issued February 27, 1990.
   • Publication/Filing Date: Filed March 28, 1989.
   • Brief Description: US10603183 describes this patent as disclosing a horseshoe implant with cylindrical holes having smooth inner surfaces and a single stop for bone screws. It notes the non-symmetric orientation of five cylindrical holes within the cage. US10603183 explicitly distinguishes itself from this patent by providing symmetric screw hole orientation and novel screw locking mechanisms.
   • Potential Anticipation (35 U.S.C. § 102): US4904261, while disclosing an intervertebral implant, does not anticipate claims 1-18 of US10603183 due to the distinct features claimed in US10603183, such as the bi-directional angling of screw guides, symmetric screw orientation, and the specific central screw locking lever or horizontal bracket locking mechanisms.

Under 35 U.S.C. § 103, a patent claim is rendered obvious if the differences between the claimed invention and the prior art are such that the subject matter as a whole would have been obvious at the time the invention was made to a person having ordinary skill in the art (POSITA). This analysis considers what a POSITA would have been motivated to combine or modify based on the existing knowledge and problems in the field.

Based on the prior art explicitly discussed within the text of US Patent 10,603,183, the following combinations could render certain aspects of the claims obvious:

1. Bi-directional Fixating Transvertebral (BDFT) Screw/Cage Apparatus with a Central Screw Locking Mechanism

• Prior Art 1: The applicant's "aforementioned related applications" (including, but not limited to, U.S. Pat. Nos. 7,704,279, 7,846,188, 7,942,903, 7,972,363, and 8,734,516) collectively disclose a bi-directional fixating transvertebral (BDFT) screw/cage apparatus. This apparatus comprises an intervertebral cage for maintaining disc height, internal screw guides, and first and second screw members disposed within the cage, with the screws oriented bi-directionally in opposite directions. The current patent (US10603183) explicitly states that its specific locking mechanisms (central screw locking lever 24 and screw locking horizontal bracket 30) are "additional evolutionary embodiment not described in the aforementioned related applications," confirming that the core BDFT screw/cage without these specific locking mechanisms was part of the applicant's own prior art.
• Prior Art 2: U.S. Pat. No. 4,904,261 (Dove et al.) discloses a horseshoe implant, which is an intervertebral implant or cage, having cylindrical holes for bone screws and includes "one stop for the heads of the bone screws to be inserted into them". This demonstrates the recognition in the prior art of the need for some mechanism to prevent screw migration or pull-out in intervertebral implants.
• Motivation: The background section of US10603183 clearly identifies a significant problem with "conventional spinal anterior intervertebral device constructs" as their "potential for extrusion in the absence of plating." It states that such constructs are "supplemented with anterior plating to prevent extrusion". This highlights a strong motivation for a POSITA to develop more effective and integrated means to prevent screw pull-out or back-out in intervertebral fusion devices, thereby reducing or eliminating the need for supplemental plating and its associated complications.
• Rationale for Combination: A POSITA, aware of the BDFT screw/cage apparatus from the applicant's prior work (Prior Art 1) and the recognized problem of screw extrusion and pull-out in spinal implants (as acknowledged in US10603183's background and partially addressed by Prior Art 2's "stop" mechanism), would be motivated to improve the screw retention capabilities of the BDFT cage. While US4904261's "stop" is rudimentary, it establishes the desirability of retaining screws within such implants. A POSITA would readily understand the benefit of incorporating a more robust "central screw locking lever" (or a similar locking mechanism) onto the BDFT screw/cage apparatus to prevent the screws from pulling out, directly addressing the known problem of extrusion and reducing surgical morbidity. The general concept of locking screws in orthopedic implants is well-established, and applying such a known functional improvement to an existing intervertebral cage with screws would be an obvious design choice for a POSITA.

2. Improved Lumbar Facet Joint Staple Gun with Enhanced Release Mechanism

• Prior Art 1: The "aforementioned related applications" (specifically mentioning U.S. Pat. No. 8,257,370, which is titled "POSTERIOR CERVICAL AND LUMBAR INTERARTICULATING JOINT STAPLES, STAPLING GUNS, AND DEVICES FOR SPINAL FUSION"). These applications teach the existence of prior versions of lumbar facet joint staple guns. US10603183 explicitly describes its lumbar staple gun as "an evolved and lumbar staple gun which is far more user friendly than previously described embodiments by incorporating a new release mechanism".
• Motivation: US10603183 states that its new lumbar staple gun "facilitates easier insertion and removal of the staple decreasing the risk of the staple becoming loose or falling off during an operation". A POSITA is continually motivated to improve the user-friendliness, safety, and efficiency of surgical instruments. Addressing issues like difficulty in loading/unloading staples or the risk of staples falling off during surgery represents a clear motivation for improvement.
• Rationale for Combination/Modification: Given the existence of prior lumbar facet joint staple guns (Prior Art 1), a POSITA aiming to enhance user-friendliness and prevent staple dislodgement would be motivated to integrate an improved staple release mechanism. The patent describes the improvement as an "independent puller tip which can be swung open when the stapler is at its maximum open position" and which is "locked in the closed position by the first end of the hollow cylinder ... when the handle in the closed position". The principle of a release mechanism that is only operable in a specific (e.g., fully open) configuration, or a puller tip designed for easier staple engagement and disengagement, represents common mechanical design principles found in various tools. Adapting such known mechanical solutions to an existing surgical staple gun to achieve the stated benefits of easier and more secure staple handling would be an obvious modification for a POSITA.

3. Lumbar Facet Staples with Improved Ratchet Mechanisms (Flexure or Torsional Spring)

• Prior Art 1: "The embodiments illustrated in the related applications". This prior art included a lumbar facet staple that featured a "ratchet" mechanism.
• Motivation: US10603183 explicitly states that its new staple embodiments "are superior to conventional designs in that the closing mechanisms can withstand much greater force (Newtons) than a small external ratchet". This identifies a clear motivation for a POSITA: to increase the strength, rigidity, and force-resistance of the staple's closing mechanism, which is crucial for robust and stable spinal fusion applications.
• Rationale for Combination/Modification: Starting with a prior lumbar facet staple already incorporating a ratchet mechanism (Prior Art 1), and with the goal of increasing its ability to withstand greater forces, a POSITA would look to enhance the ratchet's design. Flexure springs and torsional springs are fundamental mechanical elements well-known in engineering for providing controlled resistance, biasing, and locking actions in various applications. A POSITA would find it obvious to replace a "small external ratchet" with a more robust, integrated ratchet mechanism utilizing either a flexure spring (e.g., as in staple 500) or a torsional spring (e.g., as in staple 600) to achieve a desired level of rigidity and force resistance. The choice between different spring types would be a matter of routine design optimization to "tailor" the staple to specific patient needs, as acknowledged in the patent.