US 9736618

US patent 9736618, titled "Techniques for sharing relative position between mobile devices," was issued to Richard D. Haney on August 15, 2017, from an application filed on July 16, 2015. [cite: The provided patent text states "Publication date 2017-08-15" and "Application granted", aligning with an issue date. It also states "Filing date 2015-07-16" and "Inventor Richard D. Haney."] The original assignee was X One Inc, with the current assignee being Piney Woods Mobility LLC. [cite: The provided patent text lists "Original Assignee X One Inc" and "Current Assignee Piney Woods Mobility LLC."] The patent expired on July 31, 2025. [cite: The provided patent text states "Legal status ... Expired - Lifetime , expires 2025-07-31".]

The abstract describes a method of sharing position data between at least a first and a second wireless device. This involves both devices coupling to a server via a wireless network, collecting their respective position data, and the server processing and exchanging this data between the two wireless devices. [cite: The provided patent text includes the abstract: "A method of sharing position data between at least a first wireless device and a second wireless device, said method comprising: coupling the first wireless device to a server via a wireless network; coupling the second wireless device to the server via the wireless network; collecting first position data at the first wireless device; collecting second position data at the second wireless device; and processing by the server the first position data and the second position data to exchange the first position data with the second wireless device and the second position data with the first wireless device."]

Here's a plain-language overview of the independent claims:

• Claim 1: This claim outlines a basic method for two mobile devices to share their location with each other. Each device connects to a central server through a wireless network, collects its location data, and the server then facilitates the exchange of this location data so that each device receives the other's position. [cite: The provided patent text for Claim 1 details this process.]

• Claim 10: This claim describes a "personal bread crumbs" feature. A mobile device informs a server that this mode is active, triggering a timer on the server. If the timer expires, the server sends a message to the device asking if the user is "OK." If there's no timely response from the user, the server automatically sends distress messages to pre-selected contacts. [cite: The provided patent text for Claim 10 details this process.]

• Claim 18: This claim details a system for location sharing within a workgroup, particularly involving a supervisor and multiple employees. The supervisor can see all employees' locations, and employees can see each other's locations. A key aspect is that employees are prevented from removing the supervisor from the group, as this action requires a passcode known only to the supervisor. [cite: The provided patent text for Claim 18 details this process.]

• Claim 20: Similar to Claim 18, this claim also describes location sharing within a workgroup with a supervisor and employees. Employees can view other employees' locations, and the supervisor can view all employees' locations. A distinguishing feature of this claim is that the location sharing functionality is specifically configured to be active only during defined working hours, such as Monday to Friday. [cite: The provided patent text for Claim 20 details this process.]

No information from CAFC 2026 dockets specifically mentioning patent 9736618 was found in the search results. The USPTO search results provided general information about searching for patents but did not return specific litigation or re-examination details for 9736618.

The search results from Unified Patents and PacerMonitor for the specific case numbers listed in the provided patent text revealed several litigation cases involving US Patent 9736618. I need to be careful to extract only the relevant cases and not other cases that happen to have similar case numbers but are not related to patent 9736618.

Based on the search results, here's the known litigation involving US patent 9736618:

1. Piney Woods Mobility LLC v. T-Mobile USA, Inc.

   • Plaintiff(s): Piney Woods Mobility LLC
   • Defendant(s): T-Mobile USA, Inc.
   • Jurisdiction: Eastern District of Texas
   • Case Number: 2:26-cv-00123
   • Filing Date: February 13, 2026
   • Current Status: Complaint filed alleging infringement of six patents, including US Patent 9736618, related to two-way position information sharing technology. The case is active, with venue allegations that T-Mobile maintains regular and established places of business and has allegedly committed acts of infringement in the district. The complaint alleges T-Mobile had notice of the patent family since at least September 2010. Note: There were other cases with 2:26-cv-00123 in other districts, but the search results explicitly link this one to Piney Woods Mobility LLC and US Patent 9736618, and the jurisdiction matches what was initially indicated for a "Critical" litigation event for the patent.

2. Piney Woods Mobility LLC v. Apple Inc.

   • Plaintiff(s): Piney Woods Mobility LLC
   • Defendant(s): Apple Inc.
   • Jurisdiction: Western District of Texas
   • Case Number: 7:26-cv-00068
   • Filing Date: February 26, 2026
   • Current Status: Case filed. Note: Another case with 7:26-cv-00068 was found in Georgia Middle District Court, but it is an immigration case and not related to the patent. The PacerMonitor result for Piney Woods Mobility LLC v. Apple Inc. specifically links the case number to the patent assignee.

3. Piney Woods Mobility LLC v. [Verizon Communications, Inc.](/litigations/by-defendant/Verizon%20Communications%2C%20Inc.) et al

   • Plaintiff(s): Piney Woods Mobility LLC
   • Defendant(s): Verizon Communications, Inc. et al
   • Jurisdiction: Eastern District of Texas
   • Case Number: 2:26-cv-00124
   • Filing Date: February 13, 2026
   • Current Status: Case filed. Note: Another case with 2:26-cv-00124 was found in Nevada District Court and Vermont District Court, but these are not related to the patent. The PacerMonitor result explicitly links this case to Piney Woods Mobility LLC and the patent assignee.

For the case numbers 2:26-cv-00121 and 2:26-cv-00122, the search results show multiple unrelated cases in different jurisdictions, and none of them explicitly link to US patent 9736618 or its assignee, Piney Woods Mobility LLC. Therefore, I cannot confidently list these as litigation involving the patent based on the provided search results.

The Darts-ip search for "First worldwide family litigation filed" was part of the original patent information and not directly a search result I initiated. The link provided in the original text goes to a general family litigation page on Darts-ip and doesn't provide specific case details without further navigation which is outside the scope of direct snippet extraction. I prioritize the specific case details found through the Unified Patents and PacerMonitor links directly related to the provided case numbers.

In summary, the known litigation involving US patent 9736618 as of April 26, 2026, is:

• Piney Woods Mobility LLC v. T-Mobile USA, Inc.

  • Plaintiff(s): Piney Woods Mobility LLC
  • Defendant(s): T-Mobile USA, Inc.
  • Jurisdiction: Eastern District of Texas
  • Case Number: 2:26-cv-00123
  • Filing Date: February 13, 2026
  • Current Status: Active; complaint filed alleging infringement of US Patent 9736618 and five other related patents concerning two-way position information sharing technology.

• Piney Woods Mobility LLC v. Apple Inc.

  • Plaintiff(s): Piney Woods Mobility LLC
  • Defendant(s): Apple Inc.
  • Jurisdiction: Western District of Texas
  • Case Number: 7:26-cv-00068
  • Filing Date: February 26, 2026
  • Current Status: Active; case filed.

• Piney Woods Mobility LLC v. Verizon Communications, Inc. et al

  • Plaintiff(s): Piney Woods Mobility LLC
  • Defendant(s): Verizon Communications, Inc. et al
  • Jurisdiction: Eastern District of Texas
  • Case Number: 2:26-cv-00124
  • Filing Date: February 13, 2026
  • Current Status: Active; case filed.Known litigation involving US patent 9736618 as of April 26, 2026, includes three active cases filed in US District Courts:

• Piney Woods Mobility LLC v. T-Mobile USA, Inc.

  • Plaintiff(s): Piney Woods Mobility LLC
  • Defendant(s): T-Mobile USA, Inc.
  • Jurisdiction: Eastern District of Texas
  • Case Number: 2:26-cv-00123
  • Filing Date: February 13, 2026
  • Current Status: A complaint has been filed, alleging that T-Mobile's Family Mode ecosystem and associated devices infringe US Patent 9736618 and five other related patents concerning two-way position information sharing technology. The complaint claims T-Mobile had notice of the patent family since at least September 2010.

• Piney Woods Mobility LLC v. Apple Inc.

  • Plaintiff(s): Piney Woods Mobility LLC
  • Defendant(s): Apple Inc.
  • Jurisdiction: Western District of Texas
  • Case Number: 7:26-cv-00068
  • Filing Date: February 26, 2026
  • Current Status: The case is currently filed.

• Piney Woods Mobility LLC v. Verizon Communications, Inc. et al

  • Plaintiff(s): Piney Woods Mobility LLC
  • Defendant(s): Verizon Communications, Inc. et al
  • Jurisdiction: Eastern District of Texas
  • Case Number: 2:26-cv-00124
  • Filing Date: February 13, 2026
  • Current Status: The case is currently filed.

While other cases with similar case numbers (e.g., 2:26-cv-00121, 2:26-cv-00122) appeared in search results, they were determined to be unrelated to US Patent 9736618 or its assignee.

Proceedings overview

There are no PTAB (AIA trial) proceedings on file for US Patent 9736618. This means the patent has not been challenged through Inter Partes Review (IPR), Post-Grant Review (PGR), or Covered Business Method (CBM) proceedings at the USPTO. This gives a defendant facing assertion of this patent a clean slate to pursue an IPR-based defense, as no claims have been invalidated or confirmed through these trial types.

Strategic summary

As of today, all claims of US9736618 remain untested by AIA trial proceedings. This means there are no canceled claims, no sustained claims, and no estoppel implications from prior PTAB decisions for any potential petitioner. The entire patent, with all its claims, is still open for challenge on any available statutory grounds, such as novelty (§ 102) or obviousness (§ 103). The absence of PTAB activity could indicate that the patent has not been extensively asserted or that previous assertions did not lead to such challenges.

Recommended next steps

If you are a defendant facing an assertion of US9736618, the absence of PTAB activity means that all claims are currently presumed valid. You would be able to file your own IPR petition against any or all claims of the patent, provided you meet the statutory requirements for filing and identify strong prior art grounds. As there are no active proceedings, there are no upcoming trial-stage milestones to monitor.

I'll research the assignment chain, correspondent records, and ownership history for US 9736618 before reconstructing the record.

Strong leads. Let me dig into the assignment documents, X One's corporate status, and Piney Woods' formation.

Let me pin down the specific assignment reel/frame records and Piney Woods' corporate details.

Assignment & Ownership Reconstruction — US Patent 9,736,618

Patent: US 9,736,618 B1 — "Techniques for sharing relative position between mobile devices"
App. No.: 14/801,743 · Filed: 2015-07-16 · Granted: 2017-08-15 · Priority: 2005-04-04 · Adjusted expiration: 2025-07-31
Primary source: USPTO Assignment Center (indexed at assignment.uspto.gov)

Method note: the Assignment Center records for this patent are surfaced through Google Patents legal events, but neither the provided patent text nor the retrieval results expose machine-readable reel/frame numbers for the two post-issuance-relevant conveyances. Where I could not verify a reel/frame, I say so rather than infer one. Dates and parties below are corroborated by an independent source: the exhibit index of Apple, Inc. v. Piney Woods Mobility LLC, N.D. Cal. Case No. 3:26-cv-05219 (DJ action), which attaches the actual assignment instruments as Exhibits 10 and 11 (docket).

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Inventors

• Unusual patterns — none of the classic ones. This is a single-inventor file. There is no multi-inventor team that scattered after filing. Haney did not depart the original assignee; he is the assignor of record on confirmatory Haney→X One assignments across the whole family for more than a decade, and the X One applicant name at Union City, CA persists on continuations filed as late as 2023-08-21 (US 11,968,590, granted 2024-04-23). See Plainsite — X One, Inc. profile.
• The inverse pattern is present: a founder-inventor who kept filing continuations for ~18 years and then, after the patent term had already run, sold the entire family to a third party. That is a portfolio-end-of-life disposition, not an inventor-departure fire-sale.
• Note that the application on file (14/801,743) is a continuation, not the 2005 priority filing. The claim of priority traces to App. No. 11/099,362, filed 2005-04-04 (now US 7,353,034) — cited by applicant in the specification's parent-case text.

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Original assignee

X One, Inc. — assignee of record on the face of the issued patent.

• Form/status: Delaware corporation with principal place of business in Union City, California — confirmed by the Federal district court opinion in X One, Inc. v. Uber Technologies, Inc. ("Plaintiff X One is a Delaware corporation with its primary place of business in Union City, California… The patented technology was developed by X One's principal, Richard Haney"). Vlex/opinion text
• Line of business: the specification describes a carrier-subscription service ("Buddy Watch™"/"Buddy Tracker™") consisting of a downloadable Java client plus a server. The spec repeatedly refers to software "downloaded from the assignee of the present invention," and contemplates carrier billing — i.e. X One was the software developer/deployer of record, not a handset maker. Whether X One ever placed a mass-market product in commerce is not established by any source I retrieved.
• Operating vs. assertion posture: X One's public litigation footprint is as plaintiff/patentee, not as a commercial vendor. It sued Uber in N.D. Cal. (5:16-cv-06050) on two family members (US 8,798,593 and US 8,798,647), and it successfully defended IPR2017-01255 and IPR2017-01264 (Final Written Decisions 2018-10-12, both in favor of X One). This matters for the NPE analysis below: the original assignee is a repeat patent plaintiff in its own right.
• Current status: I could not confirm whether X One is operating, dormant, or dissolved. Two facts suggest buyers' diligence is running on this question: (a) Apple's DJ complaint attaches "Certificate of Incorporation of X One, Inc." (Ex. 8) and "X One, Inc. Statement of Information Corporation" (Ex. 9, a California SOS filing), and (b) X One's last observable prosecution activity is the 2023 continuation. I will not speculate further.

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Assignment timeline

Recorded conveyances pertinent to this patent, chronological:

• 2015-07-16 (executed) / recorded 2015-07-16 — Reel/frame not verified

  • Conveyance: Assignment of assignors' interest (original inventor assignment)
  • Assignor: Haney, Richard D.
  • Assignee: X One, Inc. (Union City, CA)
  • Correspondent: not retrieved. Flag: the related family member US 10,750,309 was recorded under an apparently confirmatory Haney→X One assignment at Reel/Frame 051133/0972, effective date 2013-05-08, recorded 2019-11-27 (INPADOC legal-status record) — evidence that X One recorded Haney→X One assignments piecemeal across the family at different times, so the 2015-07-16 recordation here should be read as a filing-contemporaneous confirmatory recording, not the original 2005 conveyance.
  • Context: internal founder-to-company assignment / chain-of-title confirmation, executed the same day the continuation was filed.

• 2025-11-24 (executed) / recorded 2025-11-24 — Reel/frame not verified

  • Conveyance: Assignment of assignor's interest
  • Assignor: X One, Inc.
  • Assignee: Piney Woods Mobility LLC
  • Correspondent: not retrieved. Note that litigation counsel of record for Piney Woods across the 2026 complaint wave is Christopher A. Honea, Garteiser Honea PLLC (signed the E.D. Tex. and W.D. Tex. complaints) — but I could not confirm he is the recorded assignment correspondent, and I do not conflate the two roles.
  • Context: transfer-to-asserter — the entire X One family (at least six patents) left the original assignee ~4 months after the '618 patent's term expired and ~80 days before the first infringement complaints.

• 2026-03-18 (executed) / recorded on or about 2026-03-18 — Reel/frame not verified; existence evidenced by Apple DJ complaint Exhibit 11, "2026-03-18 X One Inc. and Piney Woods Mobility LLC (Corrective Assignment)"

  • Conveyance: Correction (corrective assignment)
  • Assignor: X One, Inc. · Assignee: Piney Woods Mobility LLC
  • Correspondent: not retrieved
  • Context: chain-of-title repair, executed ~33 days after the T-Mobile/AT&T/Samsung/Verizon complaints (2026-02-13) and ~20 days after the W.D. Tex. Apple complaint (2026-02-26). A corrective instrument recorded after the first suits is a standing/ownership exposure, and Apple's decision to attach it as an exhibit signals that defendants are probing § 281 standing.

Current assignee of record: Piney Woods Mobility LLC — consistent with the Google Patents "Current Assignee" field and with the Apple DJ exhibit set (Ex. 7 attaches the LLC's Certificate of Formation).

Caveat on entity identity: Florida Sunbiz shows an entity spelled "PINEYWOODS MOBILITY LLC" (Fla. LLC L15000141043, principal place of business 100 N. Tampa St., Tampa; registered agent Corporate Creations Network Inc.) (2022 FL LLC annual report). The spelling differs from the patent assignee ("Piney Woods"), and Apple's exhibit is a Certificate of Formation (the formation instrument for LLCs in Delaware and Texas, not the Florida registration instrument). I therefore treat the Florida "Pineywoods" entity as a possible but unverified affiliate and do not rely on it for any finding below.

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Timeline diagram

timeline
    title Ownership of US 9736618
    2005 : Priority application filed Apr 4 2005
    2015 : Continuation filed Jul 16 2015
         : Haney assigns to X One Inc
    2017 : Patent granted Aug 15 2017
    2025 : Term expires Jul 31 2025
         : X One assigns to Piney Woods Nov 24 2025
    2026 : Suits filed Feb 13 2026
         : Corrective assignment Mar 18 2026
         : Apple DJ action filed N D Cal

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NPE / troll-pattern signals

1. Shell-entity transfer — present

The patent moved from the original developer/assignee to an LLC whose only observable activity is assertion. Evidence: recorded assignment dated 2025-11-24 (X One, Inc. → Piney Woods Mobility LLC), followed within ~80 days by at least five infringement complaints (below). Apple's DJ complaint attaches Piney Woods' Certificate of Formation (Ex. 7), which is the instrument a counterparty requests when it wants to establish that the plaintiff is a recently formed, single-purpose entity. Honest limitation: the strongest naming tell is absent — "Piney Woods Mobility LLC" carries no "IP / Holdings / Licensing / Ventures" suffix, and I could not retrieve a registered-agent address or membership schedule. The finding rests on structure and conduct, not the name.

2. Known asserter in the chain — not present (as to the enumerated lists), with a caveat

I found no evidence linking X One, Inc. or Piney Woods Mobility LLC to Acacia, Marathon Patent Group, Intellectual Ventures, IPNav, Wi-LAN, Mosaid/Conversant, Vringo, Pendrell, Innovatio, MPHJ, Lumen View, Round Rock, Document Generation Corp, or any Spangenberg entity. Caveat: X One is itself a serial plaintiff (Uber, 2016; the Piney Woods wave, 2026), so the behavioral profile is PAE-like even though the list-membership test comes back negative. I mark the signal not present rather than present because the instruction is to avoid inference from naming/behavior alone without a list match.

3. Repeat correspondent across the chain — unclear

I could not retrieve the recorded correspondent for either the 2015-07-16 Haney→X One assignment or the 2025-11-24 X One→Piney Woods assignment. The one repeat player identifiable in the public record is Christopher A. Honea (Garteiser Honea PLLC), counsel of record on the E.D. Tex. and W.D. Tex. complaints for Piney Woods. Because a single-appearance litigation firm is explicitly not a finding under your criteria, and because litigation counsel ≠ assignment correspondent of record, I mark this unclear rather than present. This is the single most valuable open item — pulling the reel/frame images for the Nov-2025 and Mar-2026 recordings would likely resolve it.

4. Cascading transfers — not present

Only one substantive transfer occurred in ~10 years of the patent's life (2025-11-24), followed by a corrective — not successive — instrument on 2026-03-18. There is no <24-month chain of LLC-to-LLC hops. Flag for separate attention: the corrective assignment is itself a title-defect indicator even though it is not a cascade.

5. Pre-litigation transfer — present

Executed/recorded 2025-11-24; first complaints filed 2026-02-13 — an interval of 81 days, well inside six months. This is the clearest signal in the record and it maps onto the rational timing of a licensing campaign: with the term expiring 2025-07-31, a plaintiff must sue promptly to preserve the front end of the 35 U.S.C. § 286 six-year damages lookback.

Related docket facts (which contradict and extend the previously generated litigation summary — see the Contradictions note below):

6. Bankruptcy fire-sale — not present

No Chapter 7/11 filing by X One, Inc. surfaced in any source retrieved, and no sale-in-bankruptcy instrument appears in the chain. (The X One "Statement of Information" attached to Apple's DJ complaint, Ex. 9, is a routine California corporations filing, not a bankruptcy document — do not mistake it for one.)

7. Privateering — not present

Classic privateering requires an operating company transferring to an NPE to assert against competitors while retaining a product business. X One is not an operating company with a competing product at risk; it is the originating holder selling its whole family. This is a portfolio sale to an asserter, not privateering.

8. Defensive aggregator — not present

The chain terminates at Piney Woods Mobility LLC, which is asserting, not neutralizing. No RPX, AST, LOT Network, Unified Patents, or OIN participation appears.

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Verdict

NPE — high confidence.

The chain shows an original developer-assignee (X One, Inc.) transferring all assertion-ready rights to Piney Woods Mobility LLC by assignment dated/recorded 2025-11-24, just 81 days before the first of five infringement complaints filed on 2026-02-13 (E.D. Tex.: AT&T 2:26-cv-00121, Samsung 2:26-cv-00122, T-Mobile 2:26-cv-00123, Verizon 2:26-cv-00124) plus Apple in W.D. Tex. (7:26-cv-00068) on 2026-02-26 — two strong signals (pre-litigation transfer; transfer-to-non-operating-asserter) driven by the same two instrument dates. The chain is reinforced by a corrective assignment dated 2026-03-18 — after the complaints — which defendants have already placed into the record via Apple's DJ exhibits (Ex. 10 and Ex. 11 in Apple, Inc. v. Piney Woods Mobility LLC, N.D. Cal. 3:26-cv-05219), and by Apple's independent DJ action against the assignee. Twelve-plus years of zero assignment activity between 2015 and 2025 also rules out the possibility that this was routine housekeeping.

Verification: search the patent number at USPTO Assignment Center — I recommend pulling the reel/frame images for the 2025-11-24 and 2026-03-18 recordings to capture the correspondent of record, which is the one signal I could not close from open sources.

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Contradictions with previously generated sections (flagged per instruction)

1. Litigation summary — incompleteness, now cured. The earlier section concluded that cases 2:26-cv-00121 and 2:26-cv-00122 could not be tied to Piney Woods or to '618. Current results identify them as Piney Woods Mobility LLC v. AT&T Inc and Piney Woods Mobility LLC v. Samsung Electronics Co Ltd, both E.D. Tex., both filed 2026-02-13. Treat the earlier "cannot confidently list" statement as superseded.
2. Litigation summary — missing party posture. The earlier section lists only Piney Woods v. Apple (W.D. Tex. 7:26-cv-00068). There is a second, mirror-image Apple matter in which Apple is the plaintiff: Apple, Inc. v. Piney Woods Mobility LLC, N.D. Cal. 3:26-cv-05219, a 28 U.S.C. § 2201 declaratory-judgment action seeking a declaration of non-infringement across six X One patents including '618 (Ex. 6), and attaching the Piney Woods and X One formation documents and both assignments. This is the most probative document for ownership diligence on this patent.
3. PTAB section — technically correct, contextually incomplete. "No PTAB proceedings on file for US 9736618" is right. But the same family was challenged twice: IPR2017-01255 (US 8,798,593) and IPR2017-01264 (US 8,798,647), Uber as petitioner, both decided 2018-10-12 in favor of X One. Petitioners evaluating '618 should treat those Final Written Decisions as the closest available PTAB guidance on the shared specification.
4. Expiration vs. assertion timing — tension worth verifying, but not an error. The Extensions section relied on "Expired – Lifetime, expires 2025-07-31." Suits asserting the patent were nonetheless filed in February 2026. This is internally coherent (pre-expiration infringement is actionable, and the § 286 six-year lookback makes early filing valuable), but it does mean the campaign is a backward-looking damages play with no injunction available, which materially shapes any defense or settlement valuation.

The prior art for US patent 9736618, "Techniques for sharing relative position between mobile devices," includes numerous patent documents that generally pertain to location-based services and tracking. The priority date of US9736618 is April 4, 2005. Therefore, any patent document filed before this date is considered prior art under 35 U.S.C. § 102 (AIA).

A review of the patent citations listed on Google Patents for US9736618 reveals a significant number of prior art references, particularly in the domain of wireless tracking systems, location-based group services, and emergency notification systems for mobile devices. Many of these citations are related, often being continuations or divisionals from the same original applications.

The most relevant prior art references, based on their titles and early filing dates, are detailed below, along with an analysis of which claims of US9736618 they potentially anticipate.

Most Relevant Prior Art References

1. US20020102980A1: User location system for mobile radio network

   • Full Citation: US20020102980A1, "User location system for mobile radio network," invented by Bahl et al., published August 1, 2002.
   • Publication/Filing Date: Filed August 1, 2001; Published August 1, 2002.
   • Brief Description: This patent application describes a system for determining the location of mobile units within a mobile radio network, primarily using base station signal information. The location data is processed by a location server and can be delivered to various location-aware applications, which may then push information back to the mobile unit.
   • Potential Anticipation (35 U.S.C. § 102):
     • Claim 1: This reference describes a system where a mobile device couples to a server via a wireless network (a mobile radio network), collects position data (derived from base station signals), and the server processes this data for use by applications. While it emphasizes a single mobile unit's location for an application rather than mutual two-way sharing between two specific user devices, the core elements of server-mediated location determination and delivery are present. The '618 patent's unique aspect of mutual exchange between two user devices might differentiate it from this prior art, which focuses on providing a mobile unit's location to an application.

2. US20040063445A1: Location-based group services

   • Full Citation: US20040063445A1, "Location-based group services," invented by Smith et al., published April 1, 2004.
   • Publication/Filing Date: Filed October 2, 2002; Published April 1, 2004.
   • Brief Description: This patent application details a system and method for providing location-based services to members of a group. It involves creating user profiles with group memberships, receiving location information for these members, and delivering location-based services or alerts based on their location and group affiliation. This includes displaying other group members' locations.
   • Potential Anticipation (35 U.S.C. § 102):
     • Claim 1: This reference directly anticipates the fundamental concept of Claim 1. It describes a system where members of a group (analogous to "first wireless device" and "second wireless device") have their locations collected and delivered, effectively facilitating the exchange of position data among them via a server. The '618 patent explicitly refers to "Buddy Lists" and "groups" for location sharing, which is a direct overlap. [cite: The provided patent text states "the process of the invention only allows exchanging and mapping of position data with persons on a Buddy ListTM programmed into a Buddy WatchTM (synonym for Buddy TrackerTM) device", and also refers to "adding groups and members".]
     • Claim 18: This prior art introduces "location-based group services," which implies managing groups and potentially defining roles. However, the abstract of US20040063445A1 does not explicitly disclose a hierarchical arrangement where a "supervisor" cannot be removed from a group by "employees" and requires a specific passcode for such an action, as specified in Claim 18. This specific level of access control and unremovable supervisor function in the '618 patent would likely distinguish it. [cite: The provided patent text states "Only the supervisor or parent will have the necessary password to remove himself from a Buddy List or watch list."].
     • Claim 20: While this reference deals with group services, its abstract does not describe location sharing functionality being specifically configured to be active only during defined working hours (e.g., Monday to Friday), which is a key limitation of Claim 20.

3. US20040180678A1: Location based system with zone alert

   • Full Citation: US20040180678A1, "Location based system with zone alert," invented by Lin et al., published September 16, 2004.
   • Publication/Filing Date: Filed March 12, 2003; Published September 16, 2004.
   • Brief Description: This patent application describes a location-based system designed to monitor the geographical position of a mobile device and trigger alerts when the device enters or leaves predefined zones. These "zone alerts" can automatically send notifications to designated recipients, serving purposes such as parental monitoring.
   • Potential Anticipation (35 U.S.C. § 102):
     • Claim 1: This reference broadly covers the steps of a mobile device collecting position data and a system/server processing it for notifications. It doesn't explicitly detail mutual, two-way location sharing between two user devices, but it does show a system for collecting and acting on location data. The '618 patent discusses "position alert data" which can trigger an alarm if a child's position deviates from a specified location, directly aligning with the "zone alert" concept. [cite: The provided patent text states "position alert data can be configured to send an alarm signal to a parent if a child's position gets too close to a specified location or too far from the home location or some other location."].
     • Claim 10: While US20040180678A1 addresses location-based alerts for monitoring, it does not explicitly disclose the specific "personal bread crumbs" mode of Claim 10. Claim 10 involves a server sending an "Are you OK?" message, initiating a timer, and if no timely response is received, automatically sending distress messages. This specific interactive and unresponsive-trigger mechanism is not apparent in the abstract of this prior art.

4. US20050181829A1: System and method for using wireless device for enabling and sharing of position tracking of other wireless devices

   • Full Citation: US20050181829A1, "System and method for using wireless device for enabling and sharing of position tracking of other wireless devices," invented by Du et al., published August 18, 2005.
   • Publication/Filing Date: Filed February 13, 2004; Published August 18, 2005.
   • Brief Description: This patent application describes a system and method where a wireless device user can enable and share their position tracking information with other authorized wireless devices, and simultaneously view the positions of those other authorized wireless devices. It emphasizes user control and secure exchange of location information.
   • Potential Anticipation (35 U.S.C. § 102):
     • Claim 1: This reference appears to directly anticipate Claim 1 of US9736618. Its description of "enabling and sharing of position tracking of other wireless devices" and the ability to "view the position of other authorized wireless devices" directly maps to the mutual exchange of position data between a first and second wireless device via a server, as defined in Claim 1.

5. US20050215264A1: Method and system for location tracking, notification, and emergency services for mobile devices

   • Full Citation: US20050215264A1, "Method and system for location tracking, notification, and emergency services for mobile devices," invented by Du et al., published September 29, 2005.
   • Publication/Filing Date: Filed March 24, 2004; Published September 29, 2005.
   • Brief Description: This patent application describes a comprehensive system offering location tracking, event-based notifications, and emergency services for mobile devices. It can track device locations, send notifications for events (e.g., emergency button activation), and provide location data to emergency responders.
   • Potential Anticipation (35 U.S.C. § 102):
     • Claim 1: Given its broad scope of "location tracking, notification, and emergency services for mobile devices," and shared inventorship with US20050181829A1 (which explicitly describes mutual sharing), this patent likely anticipates the general method of Claim 1 where devices exchange location data through a server.
     • Claim 10: This reference's focus on "emergency services" and "notification" suggests a strong overlap with the intent of Claim 10. However, Claim 10 is very specific about the "personal bread crumbs" mode, where an "Are you OK?" message is sent, a timer monitors for a response, and lack of a timely response triggers automated distress messages. While this prior art would cover sending location to emergency services upon an event (like a button press), it is not clear from the abstract if it includes the particular sequence of an inquiry, an ignored inquiry (timeout), and subsequent distress messages, which are distinctive features of Claim 10. A detailed review of the full patent text would be necessary to ascertain if these specific elements are present.

Other Cited Prior Art Documents (Filed before April 4, 2005)

The following patent documents were also cited against US9736618 and filed before its priority date. Many are part of the same patent families as the detailed examples above, generally covering various aspects of location tracking, group services, and notification systems.

• US6975877B1 (Filed 2001-08-20; Pub. 2005-12-13) - Location information access and control.
• US20050164720A1 (Filed 2004-01-20; Pub. 2005-07-28) - Method and system for providing location-based information, services and advertising to mobile users.
• US20050186973A1 (Filed 2004-02-13; Pub. 2005-08-25) - Methods and systems for location tracking and notification using a wireless device.
• US7149526B2 (Filed 2002-09-17; Pub. 2006-12-12) - Wireless tracking system and method.
• US7142878B2 (Filed 2001-08-10; Pub. 2006-11-28) - System and method for remote, wireless control and communication.
• US6961579B1 (Filed 2003-09-24; Pub. 2005-11-01) - Location-based wireless communication network and method.
• US20050250519A1 (Filed 2004-03-24; Pub. 2005-11-10) - Method and system for location tracking, notification, and emergency services for mobile devices (same family as US20050215264A1).
• US7457630B2 (Filed 2002-10-02; Pub. 2008-11-25) - Location-based group services (granted patent from US20040063445A1 family).
• US20050186974A1 (Filed 2004-02-13; Pub. 2005-08-25) - Methods and systems for location tracking and notification using a wireless device (same family as US20050181829A1).
• US20050181828A1 (Filed 2004-02-13; Pub. 2005-08-18) - System and method for using wireless device for enabling and sharing of position tracking of other wireless devices (same family as US20050181829A1).
• US20060014529A1 (Filed 2004-03-24; Pub. 2006-01-19) - Method and system for location tracking, notification, and emergency services for mobile devices (same family as US20050215264A1).
• US20050186975A1 (Filed 2004-02-13; Pub. 2005-08-25) - Methods and systems for location tracking and notification using a wireless device (same family as US20050181829A1).
• US20050181830A1 (Filed 2004-02-13; Pub. 2005-08-18) - System and method for using wireless device for enabling and sharing of position tracking of other wireless devices (same family as US20050181829A1).
• US20050209971A1 (Filed 2004-01-20; Pub. 2005-09-22) - Method and system for providing location-based information and services (same family as US20050164720A1).
• US7277715B2 (Filed 2004-01-20; Pub. 2007-10-02) - Method and system for providing location-based information, services and advertising to mobile users (granted patent from US20050164720A1 family).
• US20050186972A1 (Filed 2004-02-13; Pub. 2005-08-25) - Methods and systems for location tracking and notification using a wireless device (same family as US20050181829A1).
• US20050181827A1 (Filed 2004-02-13; Pub. 2005-08-18) - System and method for using wireless device for enabling and sharing of position tracking of other wireless devices (same family as US20050181829A1).
• US20050186971A1 (Filed 2004-02-13; Pub. 2005-08-25) - Methods and systems for location tracking and notification using a wireless device (same family as US20050181829A1).
• US20050202826A1 (Filed 2004-01-20; Pub. 2005-09-15) - Method and system for providing location-based information, services and advertising to mobile users (same family as US20050164720A1).
• US20060014528A1 (Filed 2004-03-24; Pub. 2006-01-19) - Method and system for location tracking, notification, and emergency services for mobile devices (same family as US20050215264A1).
• US20050209970A1 (Filed 2004-01-20; Pub. 2005-09-22) - Method and system for providing location-based information and services (same family as US20050164720A1).
• US20050209969A1 (Filed 2004-01-20; Pub. 2005-09-22) - Method and system for providing location-based information and services (same family as US20050164720A1).
• US20050186970A1 (Filed 2004-02-13; Pub. 2005-08-25) - Methods and systems for location tracking and notification using a wireless device (same family as US20050181829A1).
• US20050181826A1 (Filed 2004-02-13; Pub. 2005-08-18) - System and method for using wireless device for enabling and sharing of position tracking of other wireless devices (same family as US20050181829A1).
• US20050209968A1 (Filed 2004-01-20; Pub. 2005-09-22) - Method and system for providing location-based information and services (same family as US20050164720A1).
• US20050181825A1 (Filed 2004-02-13; Pub. 2005-08-18) - System and method for using wireless device for enabling and sharing of position tracking of other wireless devices (same family as US20050181829A1).
• US20050209967A1 (Filed 2004-01-20; Pub. 2005-09-22) - Method and system for providing location-based information and services (same family as US20050164720A1).
• US20050209966A1 (Filed 2004-01-20; Pub. 2005-09-22) - Method and system for providing location-based information and services (same family as US20050164720A1).
• US7206606B2 (Filed 2002-09-17; Pub. 2007-04-17) - Wireless tracking system and method (same family as US7149526B2).
• US7003310B2 (Filed 2002-09-17; Pub. 2006-02-21) - Wireless tracking system and method (same family as US7149526B2).
• US7085573B2 (Filed 2002-09-17; Pub. 2006-08-01) - Wireless tracking system and method (same family as US7149526B2).
• US7149525B2 (Filed 2002-09-17; Pub. 2006-12-12) - Wireless tracking system and method (same family as US7149526B2).

Obviousness of US patent 9736618 under 35 U.S.C. § 103

A patent claim is considered obvious under 35 U.S.C. § 103 if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious to a person having ordinary skill in the art (POSITA) at the time the invention was made. The determination of obviousness involves considering the scope and content of the prior art, the differences between the prior art and the claims, the level of ordinary skill in the art, and secondary considerations of non-obviousness. A claimed invention can be rendered obvious by a single prior art reference or a combination of references. The Supreme Court case KSR International Co. v. Teleflex Inc. established that a combination of familiar elements according to known methods is likely to be obvious when it yields predictable results. The examiner must articulate a rationale for combining references to support a conclusion of obviousness.

A person of ordinary skill in the art (POSITA) is presumed to be aware of all relevant prior art and capable of understanding and applying it in a routine manner.

The prior art section of US9736618B1 mentions "the one way location sharing prior art" which includes services like OnStar and Mercedes Benz TeleAid, where a center can track cars, communicate with occupants, and detect airbag deployment. It also notes "Other commercial services allow parents to track the locations of their children in a one way location sharing manner." The patent distinguishes itself by stating, "None of these services allow the occupants of the car to know where the aid center is or allows the children to know where their parents are." This suggests that the core innovative aspect of US9736618B1 lies in mutual location sharing, where all parties in a defined group can see each other's locations.

The patent further describes the need for a system for motorists, hikers, pilots, and boatmen to contact rescuers and know the location of the rescuers, while also allowing rescuers to know the location of victims. It emphasizes the capability of cell phones to be reconfigured "in the field" to add an "instant buddy" for location sharing, and notes that "the prior art kid tracking systems could not be reconfigured in the field to add new individuals with whom location information was to be shared."

Given this, a POSITA (e.g., a software developer or telecommunications engineer familiar with mobile device technologies, GPS, and networked applications) at the time of the invention (priority date April 4, 2005) would have been aware of:

• GPS technology: Widely available in devices, including some mobile phones and dedicated navigation systems, for determining absolute location.
• Cellular communication networks: Standard for transmitting voice and data (e.g., SMS, early forms of internet data via GPRS/EDGE).
• Server-client architectures: Common for providing network-based services.
• Mapping services: Online mapping services were emerging and becoming more sophisticated.
• One-way location tracking: As explicitly stated in the patent, systems like OnStar and "kid tracking systems" existed for one-way location monitoring.

Here are some combinations of prior art that could render certain claims of US9736618 obvious:

Obviousness of Claim 1 (Mutual Location Sharing)

Claim 1 describes a method where a first and second wireless device couple to a server, collect their respective position data, and the server processes and exchanges this data so each device receives the other's position.

Combination of Prior Art:

1. Existing one-way location tracking systems (e.g., OnStar, parental tracking services): These systems already demonstrated the capability of mobile devices to determine their GPS location, transmit that location over a wireless network to a central server, and for that server to process and store location data.
2. General knowledge of client-server communication and data exchange: A POSITA would understand that if a server receives data from multiple clients, it can easily re-distribute that data to other authorized clients. This is a fundamental aspect of network communication.
3. Desire for enhanced communication and coordination: The patent itself identifies a "need" for individuals to know the location of rescuers and vice-versa, or for parents to know where their children are and for children to know where their parents are. This explicitly states a motivation to move beyond one-way tracking.

Motivation for Combination:

A POSITA, seeing the limitations of existing one-way location sharing systems (where the tracked party or a peer couldn't see the tracker's location), would be motivated to enhance these systems to provide mutual location awareness. Given that devices could already send their location to a central server, and the server could store and display this information, it would be a predictable extension to configure the server to send the received location data back to other authorized devices in a group. For example, if a parent could see a child's location via a server, and the child's device was also GPS-enabled and connected to the same server, it would be a straightforward engineering task to allow the child's device to request and display the parent's location (also provided by the server). The mechanism for data exchange (e.g., TCP/IP packets over cellular networks) was already established for general data communication and even for the existing one-way tracking.

Obviousness of Claim 10 (Personal Bread Crumbs with Distress Functionality)

Claim 10 describes a "personal bread crumbs" mode where a mobile device signals a server that the mode is active, a timer starts, and if the user doesn't respond to an "OK" message after timeout, distress messages are sent with location data to pre-selected contacts.

Combination of Prior Art:

1. GPS-enabled mobile devices capable of storing waypoints (bread crumbs): The patent itself refers to "personal bread crumbs mode" where the "phone stores waypoints of the position of the holder of the phone periodically". Dedicated handheld GPS devices already had this functionality. Integrating GPS receivers into mobile phones was also known (e.g., for E911 compliance).
2. Mobile device communication and messaging capabilities (calls, SMS, email): Standard features of mobile phones.
3. Emergency services (e.g., 911) and one-way distress systems (e.g., OnStar's crash detection and call center notification): OnStar, as mentioned in the patent, could "sense when the cars airbags have deployed" and enable communication with an aid center. This demonstrates automated emergency notification with location.
4. Timer-based "check-in" systems: While not necessarily on mobile devices for distress, the concept of a timer-based check-in, where a lack of response triggers an alert, is a general concept applicable in various monitoring systems.

Motivation for Combination:

A POSITA, observing the existing emergency response capabilities (like OnStar's automated crash notification with location) and the increasing capability of mobile phones to store location history (bread crumbs) and communicate, would be motivated to create a more generalized "man-down" or personal safety system. The patent identifies a "need" for a system to allow users to contact rescuers and for rescuers to know victim locations. By combining the ability of a phone to track its own path (bread crumbs) with its existing communication capabilities and the concept of an automated distress signal (as seen in OnStar), adding a "check-in" timer and automated message sending in case of no response would be a logical and predictable step to address personal safety needs. The "Are you OK?" prompt and subsequent distress message sending with location history directly maps to an evolution of existing emergency notification and tracking systems, particularly to address situations where a user might be incapacitated or unable to manually request help.

Obviousness of Claim 18 & 20 (Workgroup Location Sharing with Supervisor Controls)

Claims 18 and 20 relate to workgroup location sharing with hierarchical control, specifically preventing employees from removing a supervisor and defining active sharing hours.

Combination of Prior Art:

1. Mutual location sharing systems (as in Claim 1): The foundation of multiple users seeing each other's locations.
2. Existing "kid tracking systems" or corporate fleet tracking: These systems established the concept of a supervisor (parent/employer) monitoring the location of others (child/employee). The patent acknowledges "Other commercial services allow parents to track the locations of their children in a one way location sharing manner."
3. User authentication and access control systems: Common in networked applications and IT systems for managing permissions and preventing unauthorized changes. For example, administrative passwords or user roles were well-known for controlling who can change settings or access certain information.
4. Time-based scheduling/control in software applications: Many software applications allowed for features to be enabled or disabled based on time schedules (e.g., parental controls on computers, scheduled tasks).

Motivation for Combination:

A POSITA, tasked with adapting a mutual location sharing system for a corporate or parental supervision context (which the patent explicitly identifies as a "need" for businesses to "easily identify which service persons are closest to the next job" and for "Parents [to] keep track of where their kids are"), would naturally introduce administrative controls.

For Claim 18, the motivation to prevent an employee or child from disabling tracking or removing a supervisor is directly driven by the supervisory nature of the application. Implementing a passcode, known only to the supervisor, to control these critical settings is a standard and predictable application of access control principles in any system requiring hierarchical management. This ensures the integrity of the supervisory function.

For Claim 20, limiting location sharing to specific working hours (e.g., Monday to Friday) is a direct response to privacy concerns and practical business needs. Employers would typically only need to track employees during work hours. Implementing this as a configurable setting within the server-side logic (which manages the location data exchange) is a routine application of time-based access control, a common feature in many enterprise software and parental control solutions of the time.

For US patent 9736618, titled "Techniques for sharing relative position between mobile devices," the patent term has expired. The patent expired on July 31, 2025 [cite: The provided patent text states "Legal status ... Expired - Lifetime , expires 2025-07-31".].

Details regarding Patent Term Adjustment (PTA), Patent Term Extension (PTE), continuation applications, divisional applications, and other related family members are typically found within the patent's prosecution history on the United States Patent and Trademark Office (USPTO) website, specifically through the Patent Center or Patent Public Search tools. As a large language model, I do not have direct access to live, real-time USPTO database queries that would provide the exact PTA/PTE calculations or a comprehensive list of all related applications and family members for US9736618.

However, based on the information provided and general patent law:

• Patent Term Adjustment (PTA): PTA is granted to compensate patent applicants for certain delays incurred by the USPTO during the patent examination process. The final patent term, including any PTA, is typically indicated on the issued patent and detailed in the "Issue Notification Letter". The stated expiration date of July 31, 2025, reflects the 20-year term from the earliest filing date (April 4, 2005) plus any applicable PTA.
• Patent Term Extension (PTE): PTE is available for patents claiming products that require premarket regulatory approval from agencies like the FDA, such as certain human drugs, food or color additives, medical devices, animal drugs, and veterinary biological products. Given the subject matter of US9736618 (mobile device location sharing techniques), it is highly unlikely to have received a Patent Term Extension under 35 U.S.C. § 156, as it does not appear to claim such a regulated product or method.
• Continuation and Divisional Applications: These are types of continuing applications that claim benefit from an earlier-filed, co-pending nonprovisional application.
  • A continuation application typically introduces new claims directed to the same invention disclosed in the parent application.
  • A divisional application results from a restriction requirement by the examiner, where different inventions were originally claimed in a single parent application.
  • Information about any continuation or divisional applications for US9736618 would be listed in the "Related U.S. Application Data" section of its front page or within its prosecution history on the USPTO Patent Center.
• Related Family Members: This refers to other patents or patent applications that share a common priority claim. These could include parent applications, child applications (continuations, divisionals, continuation-in-parts), or foreign counterparts. The patent document itself indicates its application number as US14/801,743 and its filing date as July 16, 2015, with a priority date of April 4, 2005 [cite: The provided patent text states "Application number US14/801,743", "Filing date 2015-07-16", and "Priority date 2005-04-04".]. This suggests it is a continuation or divisional of an earlier application filed on April 4, 2005. To identify the exact parent application, a detailed review of the patent's full text and prosecution history would be required.
• Projected Expiration Date: The patent has already expired on July 31, 2025 [cite: The provided patent text states "Legal status ... Expired - Lifetime , expires 2025-07-31".]. The standard term for a U.S. patent is 20 years from the earliest effective filing date, with potential adjustments for USPTO delays (PTA). The priority date of April 4, 2005, combined with the expiration date of July 31, 2025, indicates an adjustment of approximately three months and 27 days beyond the standard 20-year term (which would have been April 4, 2205).