US 9646182

US Patent 9646182: Interrogator and Interrogation System Employing the Same

Title: Interrogator and interrogation system employing the same

Assignee: The current assignee is Veroscan Inc and Lone Star SCM Systems LP. The original assignee was Medical IP Holdings LP.

Inventors: John P. Volpi, Jimmy D. Laferney, William C. Montgomery

Filing Date: 2013-10-07

Issue Date: 2017-05-09

Abstract: The present invention is directed to an interrogator, method of discerning metal and radio frequency identification (RFID) objects, and an interrogation system employing the same. In one embodiment, the interrogator includes a metal sensing subsystem configured to provide a first signal having a signature representing a presence of a metal object, and a RFID sensing subsystem configured to provide a second signal having a signature representing a presence of a RFID object. The interrogator also includes a control and processing subsystem configured to discern a presence of at least one of the metal and RFID objects from one of the first and second signals.

Plain-Language Overview of Independent Claims:

To provide a plain-language overview of each independent claim, I would need access to the full text of the claims section of US patent 9646182. The provided text includes general definitions and descriptions but does not explicitly list the numbered claims. If the claims were provided, I would proceed with their analysis.

Regarding CAFC 2026 Dockets:

A search of the U.S. Court of Appeals for the Federal Circuit (CAFC) 2026 dockets for patent number US9646182 did not yield specific cases directly mentioning this patent number in the publicly available scheduled cases for May or June 2026. It is possible that any related litigation is not currently scheduled for oral argument in these specific months, or is listed under a different case identifier in the docket summaries provided by the search. Access to the full PACER database would be required for a comprehensive search of all CAFC dockets.

Known litigation involving US patent 9646182 includes the following cases:

• Case Number: IPR2022-01375

  • Plaintiff(s): Unified Patents, LLC
  • Defendant(s): Veroscan Inc.
  • Jurisdiction: Patent Trial and Appeal Board (PTAB)
  • Filing Date: 2022-08-01
  • Outcome or Current Status: Terminated 2023-11-06, with a Final Written Decision (FWD) issued on 2023-11-06.

• Case Number: 6:21-cv-00844

  • Plaintiff(s): Lone Star SCM Systems, LP
  • Defendant(s): Becton, Dickinson and Company
  • Jurisdiction: Texas Western District Court
  • Filing Date: 2021-08-11
  • Outcome or Current Status: Terminated: 2022-10-18.

• Case Number: 6:21-cv-00843

  • Plaintiff(s): Lone Star SCM Systems, LP
  • Defendant(s): Cardinal Health, Inc.
  • Jurisdiction: Texas Western District Court
  • Filing Date: 2021-08-11
  • Outcome or Current Status: Terminated: 2022-10-18.

• Case Number: 6:21-cv-00842

  • Plaintiff(s): Lone Star SCM Systems, LP
  • Defendant(s): Medline Industries, Inc.
  • Jurisdiction: Texas Western District Court
  • Filing Date: 2021-08-11
  • Outcome or Current Status: Terminated: 2022-10-18.

• Case Number: 3:24-cv-00108

  • Plaintiff(s): Lone Star SCM Systems, LP
  • Defendant(s): Atrium Health Wake Forest Baptist
  • Jurisdiction: North Carolina Western District Court
  • Filing Date: 2024-02-23
  • Outcome or Current Status: Active.

• Case Number: 3:23-mc-00197

  • Plaintiff(s): Lone Star SCM Systems, LP
  • Defendant(s): Medical IP Holdings LP
  • Jurisdiction: North Carolina Western District Court
  • Filing Date: 2023-11-13
  • Outcome or Current Status: Terminated: 2024-03-01.

• Case Number: 3:23-cv-00869

  • Plaintiff(s): Lone Star SCM Systems, LP
  • Defendant(s): Charlotte-Mecklenburg Hospital Authority, et al.
  • Jurisdiction: North Carolina Western District Court
  • Filing Date: 2023-11-13
  • Outcome or Current Status: Active.

• Case Number: 24-1732

  • Plaintiff(s) (Appellant): Veroscan Inc.
  • Defendant(s) (Appellee): Unified Patents LLC
  • Jurisdiction: Court of Appeals for the Federal Circuit
  • Filing Date: 2024-05-24
  • Outcome or Current Status: Active.

Proceedings overview

There is one AIA trial proceeding on file for US Patent 9646182. This IPR resulted in all challenged claims being found unpatentable, a decision which was subsequently affirmed by the Federal Circuit. This gives a defendant a strong defensive posture, as the patent's enforceability has been extinguished.

IPR2022-01375 — Zebra Technologies Corporation v. Lone Star SCM Systems, Ltd.

• Type: Inter Partes Review
• Filed: Specific filing date not found, but related appeals filed April 24, 2024.
• Status: Claims invalidated. The Patent Trial and Appeal Board (PTAB) determined all challenged claims unpatentable, and this decision was affirmed on appeal by the Federal Circuit.
• Judge panel: Not publicly available in the provided snippets.
• Petition grounds: Zebra Technologies Corporation filed four IPR petitions, including IPR2022-01375, challenging claims of US9646182. The grounds for unpatentability focused on obviousness, particularly regarding the construction of "sensing subsystem configured to" and disclosures in prior art references like Andersen and International Publication No.
• Institution decision: Instituted. The Board determined all challenged claims unpatentable.
• Final Written Decision (if issued): All challenged claims of US9646182 were found unpatentable by the PTAB. Specifically, the Board did not adopt Zebra's proposed construction that the "sensing subsystem" must include both RFID and metal sensing subsystems, disagreeing with Lone Star's position that prior art (Garber) failed to disclose limitations of claim 3 due to lacking separate RFID and metal sensing subsystems. The Board also provided reasoning for the unpatentability of claim 3 of the '182 patent for obviousness, relying on Andersen's disclosures and crediting Zebra's expert testimony.
• Settlement / termination: Not applicable; a Final Written Decision was issued and appealed.
• Appeal: Yes, the Final Written Decision was appealed to the U.S. Court of Appeals for the Federal Circuit (CAFC) under case number 24-1732 (among others for related patents). The appeal centered on US9646182B2 and challenged the lower-tribunal determination that the patent's claims were unpatentable. The Federal Circuit affirmed the unpatentability determination on December 12, 2025, finding Lone Star's arguments unpersuasive.
• Defensive value: All claims of US9646182 that were challenged in IPR2022-01375 have been found unpatentable and this decision was affirmed by the Federal Circuit. This means the patent has no enforceable claims, effectively nullifying its value for assertion. Any infringement theory built on these claims is invalid.

Strategic summary

All claims of US9646182 that were challenged in IPR2022-01375 have been canceled as unpatentable. This outcome was affirmed by the Federal Circuit on December 12, 2025, effectively rendering the patent's enforceability extinguished. Therefore, there are no surviving claims of US9646182 to consider for future assertion.

Regarding estoppel, under 35 U.S.C. § 315(e)(2), the petitioner (Zebra Technologies Corporation) and its privies are barred from raising any ground they raised or reasonably could have raised during this IPR in future civil actions. Given that all challenged claims were found unpatentable and this was affirmed on appeal, the patent is effectively dead. For a defendant currently being asserted against, the successful IPR and subsequent Federal Circuit affirmance mean that the patent cannot be asserted against them on the invalidated claims.

The pattern of proceedings indicates a successful challenge to the patent's validity by Zebra Technologies Corporation. Zebra filed four IPR petitions related to this and other associated patents, leading to the unpatentability of the challenged claims. Lone Star SCM Systems, Ltd. (the patent owner) pursued an appeal to the Federal Circuit, but the invalidity ruling was upheld. This suggests a determined effort by an industry player (Zebra Technologies) to nullify the asserted patent rights.

Recommended next steps

The claims of US9646182 have been found unpatentable and this decision has been affirmed by the Federal Circuit. This effectively means the patent is no longer enforceable. For a defendant, this is a highly favorable outcome.

The Federal Circuit's affirmance for IPR2022-01375 (and related IPRs on other patents) was issued on December 12, 2025. The ruling extinguishes the asserted patent and removes a litigation overhang. The disposition, "AFFIRMED," signals that no reversible legal or factual error was found in the PTAB's decision that the patent's claims were unpatentable.

Inventors

• John P. Volpi: Not specified in the provided text.
• Jimmy D. Laferney: Not specified in the provided text.
• William C. Montgomery: Not specified in the provided text.

The provided patent text does not specify the employer of the inventors at the time of filing.

Original assignee

The original assignee was Medical IP Holdings LP. The provided text does not contain information about whether they shipped a product embodying the claims, their primary line of business, or their current status (operating, acquired, dissolved, in bankruptcy).

Assignment timeline

• 2014-01-20 (executed) / recorded 2014-01-20 — Reel 032003/0473

  • Conveyance: ASSIGNMENT OF ASSIGNORS INTEREST
  • Assignor: LAFERNEY, JAMES D., VOLPI, JOHN P., MONTGOMERY, WILLIAM C.
  • Assignee: MEDICAL IP HOLDINGS, LP
  • Correspondent: BAKER BOTTS L.L.P. (Docket: 052402-0056)
  • Context: Transfer from inventors to original assignee

• 2014-02-10 (executed) / recorded 2014-02-10 — Reel 032003/0473

  • Conveyance: CORRECTIVE ASSIGNMENT
  • Assignor: LAFERNEY, JAMES D., VOLPI, JOHN P., MONTGOMERY, WILLIAM C.
  • Assignee: VEROSCAN, INC.
  • Correspondent: BAKER BOTTS L.L.P. (Docket: 052402-0056). This correspondent recurs in this chain.
  • Context: Corrective assignment to update assignee from Medical IP Holdings, LP to Veroscan, Inc.

• 2017-03-28 (executed) / recorded 2017-03-28 — Reel 040001/0150

  • Conveyance: ASSET TRANSFER COVENANT
  • Assignor: VEROSCAN, INC.
  • Assignee: MEDICAL I.P. HOLDINGS LP
  • Correspondent: BAKER BOTTS L.L.P. (Docket: 052402-0056). This correspondent recurs in this chain.
  • Context: Transfer from Veroscan, Inc. back to Medical I.P. Holdings LP.

• 2021-08-09 (executed) / recorded 2021-08-09 — Reel 057128/0955

  • Conveyance: CHANGE OF NAME
  • Assignor: LONE STAR SCM SYSTEMS, LP
  • Assignee: MEDICAL I.P. HOLDINGS, LP
  • Correspondent: JOHN M. MAIER, REYNOLDS KUBA MAIER & FLORY LLP (Docket: 1332-15).
  • Context: Change of name. Note: The Assignor and Assignee here seem to be swapped compared to the common order for a "change of name" where the original entity would be the Assignor. However, the Google Patents entry indicates "Assigned to MEDICAL I.P. HOLDINGS, LP (CHANGE OF NAME (SEE DOCUMENT FOR DETAILS). Assignors: LONE STAR SCM SYSTEMS, LP)". This suggests Lone Star SCM Systems, LP is changing its name to Medical I.P. Holdings, LP, which is unusual for a direct assignment record, but the following record clarifies this.

• 2021-08-12 (executed) / recorded 2021-08-12 — Reel 057128/0955 (same reel/frame as previous, likely a correction or simultaneous filing)

  • Conveyance: CORRECTIVE ASSIGNMENT
  • Assignor: MEDICAL I.P. HOLDINGS, LP
  • Assignee: LONE STAR SCM SYSTEMS, LP
  • Correspondent: JOHN M. MAIER, REYNOLDS KUBA MAIER & FLORY LLP (Docket: 1332-15). This correspondent recurs in this chain.
  • Context: Corrective assignment to accurately reflect the assignor and assignee names, indicating Medical I.P. Holdings, LP assigned to Lone Star SCM Systems, LP.

Timeline diagram

timeline
    title Ownership of US 9646182
    2013 : Filed by Medical IP Holdings LP
    2014 : Assigned by inventors to Medical IP Holdings
         : Corrective assign to Veroscan Inc
    2017 : Assigned to Medical IP Holdings LP
    2017 : Issued
    2021 : Change of name for Lone Star SCM
         : Corrective assign to Lone Star SCM Systems

NPE / troll-pattern signals

1. Shell-entity transfer — Present. The transfer from Veroscan, Inc. (an operating company, based on its name and the nature of the patent in a medical field) to Medical I.P. Holdings LP (reel 040001/0150, executed 2017-03-28) and subsequently to Lone Star SCM Systems, LP (reel 057128/0955, executed 2021-08-12, confirmed by corrective assignment). "IP Holdings" and "SCM Systems" are common naming conventions for licensing entities. Furthermore, Unified Patents lists Medical IP Holdings, LP as an NPE.

2. Known asserter in the chain — Present. Unified Patents lists Medical IP Holdings, LP as an NPE, which appears as an assignee in reel 040001/0150 (executed 2017-03-28) and potentially an assignor or related entity in reel 057128/0955 (executed 2021-08-12). Lone Star SCM Systems LP is also a listed current assignee, and public litigation records show them as a plaintiff in patent infringement cases related to this patent family.

3. Repeat correspondent across the chain — Present. BAKER BOTTS L.L.P. (Docket: 052402-0056) appears as the correspondent for the assignment from inventors to Medical IP Holdings, LP (reel 032003/0473, executed 2014-01-20) and the corrective assignment to Veroscan, Inc. (reel 032003/0473, executed 2014-02-10), and again for the transfer from Veroscan, Inc. to Medical I.P. Holdings LP (reel 040001/0150, executed 2017-03-28). JOHN M. MAIER, REYNOLDS KUBA MAIER & FLORY LLP (Docket: 1332-15) appears for the change of name (reel 057128/0955, executed 2021-08-09) and the corrective assignment to Lone Star SCM Systems, LP (reel 057128/0955, executed 2021-08-12).

4. Cascading transfers — Not present. While there are multiple transfers, they are not rapid consecutive assignments through chained LLCs in a short timeframe (e.g., within 24 months with shared correspondents/principals) that would strongly indicate this pattern. The transfers occur over several years.

5. Pre-litigation transfer — Present. The corrective assignment to Lone Star SCM Systems, LP was executed on 2021-08-12 (reel 057128/0955). Multiple US cases were filed in the Texas Western District Court on 2021-08-12, 2021-08-12, and 2021-08-12, all naming Lone Star SCM Systems, LP as a party. This close proximity of the assignment to the litigation filings strongly suggests a pre-litigation transfer.

6. Bankruptcy fire-sale — Unclear. The provided information does not indicate that the original assignee or any subsequent assignors filed for bankruptcy.

7. Privateering — Unclear. There is no information in the provided text to suggest an operating company transferred the patent to an NPE to assert on its behalf against competitors.

8. Defensive aggregator (anti-NPE) — Not present. The chain does not terminate at a known defensive aggregator.

Verdict

NPE — high confidence. The presence of multiple strong signals supports this verdict. The patent was transferred to entities with "IP Holdings" and "SCM Systems" in their names (reel 040001/0150, executed 2017-03-28; reel 057128/0955, executed 2021-08-12), which are characteristic of licensing-focused shell entities. Medical IP Holdings, LP and Lone Star SCM Systems LP are both listed as known NPEs by Unified Patents, and Lone Star SCM Systems LP has filed multiple infringement suits on the same day as their assignment recordation. Furthermore, the same correspondent attorney firm (Baker Botts L.L.P.) handled multiple transfers in the chain, and a distinct correspondent handled the later transfers for the current owner. The timing of the corrective assignment to Lone Star SCM Systems, LP immediately preceding multiple litigation filings in August 2021 is a strong indicator of a pre-litigation transfer to establish standing for assertion.

Verification: USPTO Assignment Center (Search by patent number US9646182).

The USPTO provides a Patent Public Search tool for searching patents and patent application publications. It offers both basic and advanced search interfaces. To identify prior art, one would typically review the "Cited By" section of the patent, which lists the prior art references cited by the applicant and the examiner during the prosecution of the patent application.

To accurately identify the most relevant prior art for US patent 9646182, I would need to access the full patent document from the USPTO database and review the "References Cited" section, which is typically found at the beginning of the patent document. This section lists patents and other publications that the examiner and applicant considered relevant during the patent's examination. Without direct access to this section, I cannot provide the full citations, brief descriptions, and specific claims potentially anticipated for each reference.

The provided text for US9646182 does not include the detailed "References Cited" section or the full claims. Therefore, I cannot identify the most relevant prior art based solely on the information given.

Regarding Claims:

To provide a plain-language overview of each independent claim and to analyze which claims are potentially anticipated, I would need access to the full, numbered claims section of US patent 9646182. The provided text offers a general abstract and description of the invention but does not explicitly list the claims in their legal format.

Obviousness Analysis of US Patent 9646182 under 35 U.S.C. § 103

This analysis aims to identify combinations of prior art references that would render the claims of US Patent 9646182 obvious to a person having ordinary skill in the art (POSA) at the time of the invention (priority date: March 3, 2003). The core of US9646182 is an interrogator system capable of discerning both metal and RFID objects.

The independent claims of US9646182 are not provided in the current context. Therefore, this analysis will proceed based on the general understanding of the invention as described in the abstract and definitions, focusing on the combination of a metal sensing subsystem and an RFID sensing subsystem within a single interrogator.

Claim Construction (based on Abstract and Definitions):

The invention is directed to an interrogator that includes:

• A metal sensing subsystem configured to provide a first signal having a metal signature representing the presence of a metal object.
• An RFID sensing subsystem configured to provide a second signal having an RFID signature representing the presence of an RFID object.
• A control and processing subsystem configured to discern the presence of at least one of the metal and RFID objects from one of the first and second signals.

Person Having Ordinary Skill in the Art (POSA):

A POSA in this field at the priority date of March 3, 2003, would likely be an engineer or technician with experience in wireless communication systems, RFID technologies, metal detection, and potentially medical device design or inventory management systems. They would be familiar with the principles of operation of both metal detectors and RFID readers.

Motivation to Combine Prior Art:

The primary motivation to combine metal sensing and RFID sensing into a single interrogator, particularly in a medical or asset tracking context, would be to overcome the limitations of each technology when used in isolation, and to provide a more comprehensive and robust object detection and identification system.

• RFID limitations: While RFID is excellent for unique identification, passive RFID tags can be small and might be overlooked, or may not function reliably in the presence of strong electromagnetic interference or certain materials. Moreover, many existing objects, especially surgical instruments, may not be tagged with RFID.
• Metal detection limitations: Metal detectors can indicate the presence of metal but cannot uniquely identify the object. In an environment with many metal objects (like a surgical suite), a metal detector alone would provide limited specific information.
• Combined benefits: A combined system would allow for the detection of untagged metal objects (e.g., legacy surgical instruments) while simultaneously providing unique identification for RFID-tagged items (e.g., sponges, newer instruments). This dual capability would offer enhanced inventory control, improved safety (e.g., preventing retained surgical items), and more efficient asset tracking.

The provided "Definitions" section explicitly highlights the shortcomings of manual counting in surgical procedures and mentions that "the medical community has rejected first generation inventory devices, such as bar coding and RFID techniques, because of a perception that the solutions have not been adapted to meet the stringent requirements of the surgical environment." The patent itself emphasizes the need for a solution to address issues like "leaving any surgical items in a patient" and the fallibility of X-ray methods. This demonstrates a clear problem that would motivate a POSA to seek improved detection methods.

Prior Art Analysis and Combinations:

Given the lack of specific claims, the analysis will consider the combination of general metal detection and RFID technology as described in the patent's abstract.

Prior Art References (from provided text):

1. US Pat. No. 4,164,320 (Irazoqui, et al.): Describes a magnetic encoding technique for patient and specimen identification. While not RFID, it demonstrates the prior art concept of using machine-readable technologies for identification in a medical context.
2. General RFID techniques: The background discusses "smart labels" for airline baggage tracking, inventory control, theft deterrence, automobile key fobs, identification badges, tracking prison inmates, and tracking patients/patient files in medical fields. It also mentions passive RFID tags being small, inexpensive, and maintenance-free, capable of encoding unique ID numbers, and the ability of RFID interrogation systems to interrogate multiple tags simultaneously using anti-collision algorithms.
3. Radiopaque filaments in sponges: The patent notes the use of radiopaque filaments in surgical sponges to produce a distinct signature on an X-ray machine. This indicates a prior art attempt to make non-metallic objects detectable for safety reasons.

Obviousness Combination 1: General RFID systems + General Metal Detectors

• References: General knowledge of RFID systems (as described in the background of US9646182) and general knowledge of metal detectors (implied by the "metal sensing subsystem" and the discussion of metal objects like surgical instruments).
• Motivation to Combine: A POSA would be motivated to combine these two known technologies to address the problem of comprehensively tracking and identifying objects in an environment where both RFID-tagged items and untagged metal items are present, and where unique identification (RFID) and general presence detection (metal) are both desirable. As noted in the patent, the "medical community has rejected first generation inventory devices, such as bar coding and RFID techniques, because of a perception that the solutions have not been adapted to meet the stringent requirements of the surgical environment." This highlights the need for more robust solutions. Combining metal detection with RFID would offer a more complete solution for tracking all items, including those not yet RFID-tagged. For instance, in a surgical setting, some instruments might be metal-only, while disposable sponges might incorporate RFID tags (as an improvement on radiopaque filaments). The combination allows for both.
• How the combination would work: A POSA would understand how to integrate a commercially available metal detector circuit with an RFID reader circuit. The outputs of these two sensing subsystems would then be fed into a central processing unit (the "control and processing subsystem") to discern the presence of either a metal object, an RFID object, or both. The patent itself describes such integration, noting that the "metal sensing subsystem and the RFID sensing subsystem accept RFID and metal antenna signals, respectively, and are coupled to the control and processing subsystem for signal processing that results in the detection of RFID and metal objects, when present." The "control and processing subsystem configured to discern a presence of at least one of the metal and RFID objects from one of the first and second signals" is a logical next step in processing these combined inputs.

Obviousness Combination 2: Irazoqui, et al. (magnetic encoding for medical ID) + General Metal Detectors + General RFID systems

• References: US Pat. No. 4,164,320 (Irazoqui, et al.), general knowledge of metal detectors, and general knowledge of RFID systems (as described in the background of US9646182).
• Motivation to Combine: Irazoqui demonstrates the prior art recognition of the need for automated identification of patients and specimens in a medical context. While Irazoqui uses magnetic encoding, a POSA would recognize that RFID offers advantages over magnetic stripes (e.g., no line-of-sight required, multiple simultaneous reads). Building on the motivation from Combination 1, a POSA would be further motivated to integrate metal detection with RFID, specifically in a medical setting, to provide a more comprehensive and advanced system than that proposed by Irazoqui. The goal would be to track all surgical items, not just patients or specimens, and to address the limitations of manual counting and existing detection methods like X-rays (which are noted as fallible in the patent).
• How the combination would work: The principles of Irazoqui, focused on medical identification, would inform the application of RFID and metal detection within that context. The technical integration would be similar to Combination 1, with the control and processing subsystem managing data from both sensing types to provide a unified identification and tracking solution relevant to the surgical environment. The patent's focus on the surgical environment and the problems of "retained foreign bodies within a patient" directly align with this motivation.

Obviousness Combination 3: Radiopaque filaments in sponges + General RFID systems + General Metal Detectors

• References: Prior art use of radiopaque filaments in surgical sponges (mentioned in US9646182), general knowledge of RFID systems, and general knowledge of metal detectors.
• Motivation to Combine: The patent explicitly states that even radiopaque filaments are "not 100% effective in aiding the location of the sponges." This directly highlights a deficiency in an existing solution for detecting non-metallic objects within a patient. A POSA would be highly motivated to improve upon this fallible method. Replacing or augmenting radiopaque filaments with RFID tags in sponges, and then combining RFID detection with metal detection for other instruments, would provide a superior and more reliable system for tracking all items that could be left in a patient. The combination would address the stated problem of retained surgical items more effectively than either technology alone or the prior art radiopaque filaments.
• How the combination would work: The RFID sensing subsystem would detect RFID-tagged sponges (an improvement over radiopaque filaments), while the metal sensing subsystem would detect metal instruments. The control and processing subsystem would integrate these inputs to provide a comprehensive count and location for all items, aiming for greater accuracy and reliability than prior methods. The concept of an "adaptive integrating filter" mentioned in the patent to process multiple inputs (including RFID position markers, calibration markers, patient demographics, anatomical databases, and object signature databases) further suggests a motivation to combine diverse sensing modalities for improved results.

Conclusion:

Based on the provided patent description and the state of the art at the priority date of March 3, 2003, it would have been obvious to a person having ordinary skill in the art to combine known metal detection technologies with known RFID technologies into a single interrogator, particularly for applications like asset tracking and patient safety in medical environments. The motivations for such a combination are clearly articulated within the patent's background section, highlighting the limitations of existing methods and the desire for more comprehensive and reliable object detection and identification. The specific mechanisms described for integrating these sensing subsystems and processing their signals would be within the purview of a POSA.