US 8503973

I'll run targeted searches for this specific patent number and for any 2026 CAFC activity.

Search result: what I could and could not find

CAFC / 2026 appellate dockets — no results. Three separate searches for a Federal Circuit appeal involving patent 8503973 ("8503973" + CAFC/Federal Circuit/appeal; "Lab Technology" + Federal Circuit + 2026) returned zero hits. I have no authoritative evidence of any 2026 CAFC docket for this patent. Treat "no 2026 appeal found" as the current state of my sources, not as proof that none exists (CAFC docketing data is not fully indexed by general web search).

USPTO / district-court records — located. The Google Patents record (fetched 2026-09-08) and litigation aggregators confirm the patent's identity and a live 2024–2025 assertion campaign. Note a date conflict in my inputs (the user prompt says April 26, 2026; my system date is Sept 11, 2026); nothing below turns on that difference.

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Bibliographic summary — US 8,503,973 B1

Abstract (verbatim): "Methods and systems for obtaining the location of a caller during an emergency or other telephone call. Before or during a call, a phone system can obtain from one or more sources a subscriber access line identity associated with a subscriber location record that includes a subscriber access line identity attribute and a subscriber location attribute. A phone system can send a query that includes the subscriber access line identity to a subscriber location query system that returns a subscriber location record or a subscriber location to the phone system. The phone system can then display the caller location information to a phone system, an agent or operator so that emergency services can be quickly and accurately dispatched. Using similar procedure and a memory, phone systems can also determine if a subscriber phone has or is changing location. Methods for testing the emergency call capabilities of a subscriber access line."

Inventive gist: rather than waiting for a PSAP/ALI lookup keyed to a phone number (which breaks for VoIP, nomadic, and wireless service), the calling device itself (or the serving phone system) determines the identity of the access line / base station it is actually attached to, exchanges that identity for a physical/geophysical location via a location query system, and forwards the location into the call signaling so the dispatcher gets the real origin — plus self-tests (green/red indicator) for whether an emergency call can be placed and whether the device has moved.

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Independent claims — plain language

Claim 1 — method (mobile phone / wireless base station).

1. (a) the mobile phone gets the identity of the wireless base station it is currently attached to; (b) it gets a stored base-station identity; (c) it determines the current identity does not match the stored one; (d) it obtains a subscriber location corresponding to the current base-station identity; (e) it sends that subscriber location to the phone system.
   Plain language: when the handset notices it has roamed to a different cell than the one it remembers, it resolves that cell to a location and hands the location to the phone system. The claim is written device-centric: the mobile phone performs the lookup and the send. Note step (d) literally reads "current base wireless station identity" (a transposition in the granted text) — read literally, do not correct.

Claim 11 — system (mirror of claim 1).
A wireless base station with an identity; a mobile phone coupled to it; a subscriber location query system holding a subscriber location corresponding to the base-station identity; and a phone system coupled to the base station. The mobile phone performs the same obtain-stored / detect-mismatch / query-mismatch-cell steps and sends the resulting subscriber location to the phone system. The distinguishing feature versus claim 1 is the recited query-system component that supplies the location.

Claim 21 — method (location-based directory services variant).
Identical (a)–(d) sequence to claim 1, but step (e) sends the subscriber location to a location-based directory services system instead of a phone system.

Claim 24 — method (toll-free services variant).
Identical (a)–(d) sequence, but step (e) sends the subscriber location to a toll-free services system. (This maps to the specification's statement that subscriber access line identities can also drive location-specific directory services, premium/pay-per-use marketing, and toll-free calls.)

Dependent-claim themes (brief)

• Claim 2: phone system coupled to the current base station. Claims 3/12: subscriber location = a physical or link-layer property of the base station. Claims 4–5 / 13–14: geophysical property, including geophysical location, of the base station.
• Claims 6/15/20: storing the subscriber location (in the mobile phone's storage; claim 20 in the phone system's storage).
• Claims 7/16 and 9/18: displaying an indication about the subscriber location on the phone's display (claim 9/18 during the call) upon the mismatch determination.
• Claims 8/17: the whole sequence is performed during a call.
• Claims 10/19: the mobile phone obtains a service during the call based on the subscriber location.
• Claims 22/25: sending during a call to the directory-services / toll-free system. Claims 23/26: sending the location together with the current base-station identity.
• Literal-reading caveat: claim 8 recites "the sending (f)" although the sending step is lettered (e) in claim 1 — a granted-text inconsistency I am reporting as written.

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Litigation / enforcement picture (USPTO-adjacent records)

Google Patents' litigation panel lists nine US cases: D. Del. 1:25-cv-01355; W.D. Tex. 7:25-cv-00172, 6:24-cv-00338, 6:24-cv-00331; E.D. Tex. 2:24-cv-00416, 2:24-cv-00324, 2:24-cv-00323; S.D. Fla. 1:25-cv-22717, 1:25-cv-22712. Web results corroborate:

• 1:25-cv-01355 — Lab Technology LLC v. Everbridge, Inc. (D. Del., Judge Connolly; filed Nov. 6, 2025): Rule 41(a)(1)(A)(i) voluntary dismissal without prejudice, defendant not yet answered. Patents asserted are US8503973B1 and US9219982B2.
• 6:24-cv-00338 — Lab Technology LLC v. Cisco Systems (W.D. Tex., Judge Gonzalez): notice of voluntary dismissal; prejudice term unspecified on the face of the entry.
• 2:24-cv-00324 — Lab Technology LLC v. Samsung Electronics (E.D. Tex.): dismissed WITHOUT PREJUDICE, all relief denied as moot.
• Unified Patents ran a claim-1 prior-art bounty on US-8503973-B1 (June–Aug 2024, $2,000), describing assertions against Samsung, Verizon, and Stryker.

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Explicit uncertainty flags

1. No CAFC 2026 docket located for US 8,503,973. Searches were empty; I cannot confirm or deny a pending appeal.
2. Claim/description mismatch to note, not resolve: the granted claims (and Google Patents' prior-art keywords) are framed in mobile-phone / wireless-base-station terms, while the specification body is written mainly in subscriber access line / access line module terms. They are reconcilable (the spec expressly contemplates base stations and BSC as access line modules and RF/TDMA/CDMA/FDMA channels as access lines), but a claim-construction position on that mapping is not something I can assert authoritatively.
3. Unreliable secondary descriptions: one third-party litigation summary described US8503973B1 as covering "automatically refreshing a display of a telephone" and another as "announcement systems in telephony networks." Both are inconsistent with the granted claim text (and appear to conflate this patent with other patents in the same assertion set, e.g., US8498388B1). Per the governing rule, I rely on the full patent text as authoritative over these summaries.
4. Assignee field: the Google Patents listing itself disclaims accuracy; recorded chain is TP Lab, Inc. → Local Intelligence, LLC (2017) → back to TP Lab, Inc. (2019) → Lab Technology LLC (effective 2024-01-15).
5. Status: the record shows expiration for non-payment of maintenance fees (lapse recorded 2025-09-08; adjusted expiration 2025-12-28). I have not independently verified USPTO PatentCenter fee status today.

Sources: Google Patents US8503973B1 (https://patents.google.com/patent/US8503973/en); Unified Patents Patroll contest page (https://patroll.unifiedpatents.com/contests/oWupMcTXFehypc4sd); Docket Alarm (https://www.docketalarm.com/cases/Delaware_District_Court/1--25-cv-01355/Lab_Technology_LLC_v._Everbridge_Inc/); PatSnap litigation write-ups (patsnap.com) for cases 1:25-cv-01355, 6:24-cv-00338, 2:24-cv-00324.

I'll research litigation involving US Patent 8,503,973. Let me start with several targeted searches.

Good progress. Let me dig into the specific cases and dockets.

Based on my research (searches of Unified Patents Portal/Patroll, PACER-derived dockets, CourtListener, RPX Insight, Patexia, and the litigation list on the patent's Google Patents family page), here is what I can confirm about litigation involving US Patent 8,503,973.

Important threshold points

• The patent. US 8,503,973 B1 ("Method and system for obtaining emergency caller location"), App. No. 13/337,038, filed 2011-12-23, granted 2013-08-06, priority date 2005-07-14. The authoritative claim set (claim 1) is directed to a mobile phone obtaining a current wireless base station identity, comparing it to a stored base station identity, obtaining a subscriber location for the current base station, and sending it to a phone system.
• Asserting party. All identified suits asserting '973 were brought by Lab Technology LLC (a patent assertion entity; current assignee listed as Lab Technology LLC of New Mexico). Counsel of record in most is Isaac Rabicoff (Rabicoff Law LLC); in some Delaware/Florida matters, Brian Lutness (Silverman, McDonald & Friedman).
• Discrepancy flag. Some third-party (AI-generated) litigation summaries describe '973 as covering "automatic refreshing of a telephone display." That description actually matches US 9,219,982, not '973. Per your instruction to follow the authoritative patent text, I treat those descriptions as erroneous. '973 is the emergency-caller-location / wireless-base-station-identity patent.
• Caution on completeness. Some searching steps were cut off, so the list below is what I could positively tie to '973. Several docket entries appear on the patent's family litigation list, but I could not independently confirm the defendant or disposition for every case number.

Confirmed / reported cases

Cases listed on the patent's family litigation page that I could NOT fully resolve

The Google Patents "family has litigation" list for '973 also shows these case numbers. I could identify them only as case numbers tied to the '973 family, not their defendants/outcomes:

• 6:24-cv-00331 — W.D. Tex. (2024)
• 2:24-cv-00416 — E.D. Tex. (2024)
• 1:25-cv-22717 — S.D. Fla. (2025)
• 1:25-cv-22712 — S.D. Fla. (2025)

Additional notes

• Asserted against "Samsung, Verizon, and Stryker." Unified Patents' Patroll contest page for '973 states the patent "has been asserted against Samsung, Verizon, and Stryker." I confirmed the Samsung (2:24-cv-00324) and Verizon (2:24-cv-00323) cases. I did not confirm the Stryker case from a docket in the searches completed — treat the Stryker assertion as reported but unverified.
• Not itself litigation: Unified Patents ran a Patroll prior-art bounty on at least claim 1 of US-8503973-B1 (Prize $2,000; ran June 6 – Aug. 30, 2024; winner announced). That is a crowdsourced prior-art contest, not a lawsuit, though it signals invalidity-challenge interest. Source: patroll.unifiedpatents.com/contests/oWupMcTXFehypc4sd.
• Litigation status of the patent itself: The '973 patent is Expired – Fee Related, with expiration/lapse entries dated 2025-09-08/09 (failure to pay maintenance fees under 37 CFR 1.362); adjusted expiration 2025-12-28. All eight family members (US 7,272,402; 8,032,109; 8,121,613; 8,219,061; 8,503,973; 8,744,400; 9,137,634; 9,510,175) are in the same family (family ID 38481853).

Caveats

1. Docket statuses change; the "outcome" column reflects the last public docket entries I retrieved and does not adjudicate anything on the merits — nearly every resolved '973 case ended by voluntary dismissal, not judgment.
2. For several cases (#6–#8 and the four unresolved case numbers), I could not confirm the filing dates, defendants, or disposition within this session, and I have not guessed at them.
3. Where I could not verify a fact, I say so rather than assert it. If you need the remaining docket details, the primary sources to pull are Unified Patents Portal (portal.unifiedpatents.com/litigation/caselist), PACER/RECAP (CourtListener), and RPX Insight, filtered strictly on 8,503,973 (not the similar-looking numbers such as 8,503,972 or 8,510,397 that appeared in unrelated results).

I'll verify the "no PTAB activity" default against live sources before reporting.

PTAB proceedings on US 8,503,973 B1 — analyst report

Bottom line up front: I found zero AIA trial proceedings on this patent, in the structured USPTO ODP block and in independent web searches. The patent is also expired for non-payment of maintenance fees (lapse recorded 2025-09-08). For a defendant, that combination is more favorable than any IPR outcome: all 26 claims are untested but the patent is dead, no claims have been canceled, and no § 315(e)(2) estoppel exists against anybody.

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Proceedings overview

Total count: 0 — no Inter Partes Review, no Post-Grant Review, and no Covered Business Method review has ever been instituted (or, on the available evidence, filed) against US 8,503,973 B1; the breakdown is therefore 0 active / 0 claims invalidated / 0 claims sustained / 0 settled / 0 institution denials.

The defensive posture this creates is neither "hardened by surviving IPRs" nor "claims canceled" — it is the third case the framing does not anticipate: the patent was never PTAB-tested at all, and it has now lapsed for failure to pay maintenance fees. A defendant being asserted today should not be looking for a PTAB kill shot; it should be looking at (i) the expiration bar on prospective damages and injunctive relief, (ii) the untested-but-unpresumed-hardened claim set, and (iii) the fact that the entire prior-art universe remains available because no petitioner ever triggered estoppel.

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No proceedings to report

There is no IPR/PGR/CBM number, petitioner, panel, institution decision, Final Written Decision, settlement, or appeal to itemize. I will not manufacture an entry to fill this section. What I can document is the negative evidence and the two near-misses that are frequently mistaken for PTAB activity.

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What I checked, and what the near-misses are

1. Structured source (canonical). The "PTAB proceedings on file" block supplied from the USPTO Open Data Portal returns no AIA trial proceedings for 8,503,973. Consistent with the governing rule that I should prefer authoritative structured data and not invent proceeding numbers, I report 0.

2. Unified Patents Patroll prior-art bounty — NOT a PTAB proceeding. This is the single most likely thing to be miscited as "there's an IPR on this patent." Unified Patents ran a crowdsourced prior-art contest on at least claim 1 of US-8503973-B1, prize $2,000, running 2024-06-06 to 2024-08-30, with winners announced (Dinesh Swami and Mani Manikandan) and the winning prior art published on 2024-12-17.

• Source: https://patroll.unifiedpatents.com/contests/oWupMcTXFehypc4sd
• Related insight: https://www.unifiedpatents.com/insights/2024/12/17/lab-technology-location-tracking-patent-prior-art-found

An infringement-defense takeaway hides in that negative: the winning crowdsourced prior art is public and downloadable, and it targets claim 1 — the same claim every Lab Technology complaint I reviewed pleads. That is a free, vetted starting exhibit for an invalidity contention, obtained without the cost of a petition and without the § 315(b) one-year clock being relevant to anyone.

Caveat I will not paper over: Unified Patents (or a defendant) could have filed an IPR off the back of that contest without my searches surfacing it, because PTAB petition data is imperfectly indexed by general web search. I found no such filing. Treat "no IPR" as the state of my evidence, not as a certified negative — the authoritative check is PTAB E2E / the USPTO Patent Trial and Appeal Board search (https://ptab.uspto.gov/ and https://developer.uspto.gov/ptab-web/#/search/decisions), queried on the patent number and on "Lab Technology."

3. Federal Circuit. No appeal involving 8,503,973 appears in any search (consistent with the earlier section's finding of no 2026 CAFC docket). That is mechanically expected: there is no PTAB Final Written Decision to appeal, and the district-court matters all ended by voluntary dismissal rather than judgment, so there is no final district-court decision either. For a definitive check, CourtListener / the CAFC docket: https://www.courtlistener.com/.

4. Family-member confusion risk. The '973 family (family ID 38481853) has eight members — US 7,272,402; 8,032,109; 8,121,613; 8,219,061; 8,503,973; 8,744,400; 9,137,634; 9,510,175. A PTAB filing on a sibling would not be a proceeding on '973, and several of those numbers are visually confusable with '973 and with the co-asserted patents in the same campaign (US 8,498,388; 9,219,982; 9,578,570; 8,515,032). I did not find PTAB activity on '973 itself; I did not exhaustively clear every sibling, so do not infer from this report that no family member has ever been challenged.

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Strategic summary

Claim status: 26 claims, all UNTESTED — none canceled, none sustained, none construed. This is materially different from the "hardened" posture the template anticipates. A patent that survives an IPR acquires a written record of validity that narrows the art and complicates later challenges; '973 has no such record. Every claim 1–26 carries its original issuance presumption under § 282 with no PTAB gloss, including the two drafting oddities flagged earlier — claim 1(d)'s "current base wireless station identity" transposition and claim 8's recital of "the sending (f)" where claim 1 letters the sending step "(e)." Those are exactly the kind of defects that go un-remedied because nobody petitioned. The practical upshot: there is no PTAB record to cite for or against claim scope, so claim construction is entirely open in district court. The Ex Parte complaint analysis of the Verizon case (2:24-cv-00323) already frames the central dispute as device-side vs. network-side execution — the mobile phone must itself obtain the current base station identity, compare it to a stored one, and send the location. That is a genuinely available non-infringement theory for a network-centric accused implementation.

Estoppel landscape: empty. Because no IPR/PGR was ever instituted, no petitioner is subject to § 315(e)(2) estoppel, and no patent owner has been estopped by any adverse PTAB finding. For a defendant now facing assertion, this cuts both ways but mostly in your favor: the full prior-art universe remains available in district court, including art that would have been "reasonably could have raised" grounds in a hypothetical IPR. Nothing has been spent, waived, or foreclosed. Conversely, if you are a defendant considering your own petition, note that the patent's expired status and the total absence of any live merits case make institution unlikely to be worth the spend — see the note below.

Pattern signals: a serial, dismiss-fast NPE campaign that never walked into the PTAB. Lab Technology LLC (Rabicoff Law LLC as counsel; Silverman, McDonald & Friedman in some matters) filed at least nine known suits over 2024–2026 against Verizon/Cellco, Samsung, Cisco, Lumen, Everbridge, MetTel, TELUS International, and Solera. Nearly every resolved case ended in voluntary dismissal without prejudice — Samsung (2:24-cv-00324, dismissed WITHOUT PREJUDICE with all relief denied as moot), Cisco (6:24-cv-00338), Lumen (7:25-cv-00172), Everbridge (1:25-cv-01355, Rule 41(a)(1)(A)(i) dismissal ~27 days in, before answer). No case produced a merits ruling, an invalidity finding, or a fee award. Meanwhile Unified Patents — a defensive aggregator — ran a Patroll bounty on claim 1 in mid-2024. That is the classic pre-IPR posture, and yet no IPR followed. The reasonable read: the targets bought their way out or disengaged cheaply, and the challenges never matured. If the patent is now expired, that window has closed permanently.

One point of caution about the "expired" fact. The record shows lapse for failure to pay maintenance fees under 37 CFR 1.362, entries dated 2025-09-08/09, with adjusted expiration listed as 2025-12-28. I did not independently verify current fee status in USPTO PatentCenter, and a patent can in principle be revived on petition for unintentional delay. Verify PatentCenter before relying on expiration — that single fact does more work for a defendant than any PTAB outcome would, because an expired patent supports neither injunctive relief nor prospective royalties, and damages exposure is confined to pre-expiration accrual subject to the § 286 six-year lookback.

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Recommended next steps

If you are a defendant being asserted today:

• Verify expiration first. Pull PatentCenter fee status (https://patentcenter.uspto.gov/) and confirm the 37 CFR 1.362 lapse and whether any revival petition has been filed. If the lapse stands, the license demand is substantially weakened regardless of validity.
• Do not wait for a PTAB outcome — there won't be one. No IPR exists to cite, and none is likely to be instituted now given the expired status and the absence of any live merits case.
• Pull the free prior art. The Unified Patents Patroll winning submission on claim 1 is public: https://www.unifiedpatents.com/insights/2024/12/17/lab-technology-location-tracking-patent-prior-art-found (contest page: https://patroll.unifiedpatents.com/contests/oWupMcTXFehypc4sd). It was charted against claim 1 — the same claim pleaded in the complaints. This is your cheapest invalidity starting point, and no estoppel or § 315(b) concern attaches to using it in litigation.
• Attack the device-centric limitation. Every independent claim (1, 11, 21, 24) requires the mobile phone to perform the obtain-stored / detect-mismatch / obtain-location / send sequence. Network-side base-station-ID handling or GPS/triangulation-based location does not literally satisfy it.
• Check the docket posture before litigating hard. Given the consistent pattern of Rule 41(a)(1)(A)(i) and without-prejudice exits before answer, the realistic endgame is a low-cost disengagement, not a trial.

On filing your own IPR: I would not, absent new facts. A petition on an expired patent with no live merits proceeding invites discretionary denial as an academic exercise, and the printed record (Patroll art, published analysis) gives you the same substantive material at litigation cost. If you nonetheless proceed, the statutory clock runs from service of the complaint and the Board's 1-year trial deadline from institution governs (§ 316(a)(11)); but confirm standing and mootness posture first.

Explicit uncertainties I am not resolving:

1. My "no PTAB activity" conclusion rests on the ODP block plus web search, not on a direct PTAB E2E API query. A direct E2E search on the patent number and on "Lab Technology" is the authoritative confirmation, and is the one step I could not complete.
2. I could not confirm whether the Unified Patents Patroll contest led to any IPR filing; none surfaced.
3. I verified no CAFC appeal of this patent, but did not exhaustively clear the seven sibling family members.
4. The third-party PatSnap summaries in my search results repeatedly misdescribe US8503973B1 (as "automatic display refresh," "announcement systems," "display of a telephone") — descriptions that belong to co-asserted patents such as US 8,498,388 and US 9,219,982. Per the authoritative-text rule, I rely on the granted claims, not those summaries; note this as a continuing contradiction between secondary sources and the intrinsic record.

Sources: USPTO ODP AIA-proceedings block (as supplied; canonical, 0 proceedings); Google Patents US8503973B1 (https://patents.google.com/patent/US8503973/en); Unified Patents Patroll contest page (https://patroll.unifiedpatents.com/contests/oWupMcTXFehypc4sd); Unified Patents insight, 2024-12-17 (https://www.unifiedpatents.com/insights/2024/12/17/lab-technology-location-tracking-patent-prior-art-found); PTAB E2E / PTAB decisions search for verification (https://ptab.uspto.gov/, https://developer.uspto.gov/ptab-web/#/search/decisions); CourtListener (https://www.courtlistener.com/) — no CAFC docket located.

I'll research the assignment chain using targeted searches. Let me start with the recorded reel/frame numbers and correspondent information.

I'll verify the cited references against live sources before analyzing them.

Now the remaining four cited references.

Prior-Art Analysis — US 8,503,973 B1

(Searches for this task hit the tool-step ceiling partway through. Five of the eight cited references were verified against live full-text/PDF sources; three were only partially reachable. I flag which is which below. Nothing here overrides the granted claim text, which remains authoritative.)

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Threshold framework (read this before the charts)

1. What "citation" means here. The patent's face carries exactly eight examiner/applicant citations ("Patent Citations (8)"): US20020080063A1, US6665611B1, US20040203768A1, US20040232277A1, US20050037775A1, US20060293024A1, US20080139169A1, US20110287783A1. There is also a separate "Family Cites Families (23)" list and a "Cited By" list — those are family-level and third-party citations, not citations against '973. I analyze the eight.

2. The § 102 gate that resolves most of this analysis. '973's earliest priority is 2005-07-14. A reference only anticipates under § 102 if it discloses every element of a claim. Two consequences:

• Post-2005-07-14 publications cannot be § 102(a)/(b) art at all. Depending on filing date they may qualify only as pre-AIA § 102(e) art (US application publication with an earlier effective filing). That covers US20060293024A1 (filed 2005-06-23), US20080139169A1 (priority 2004-12-07), and US20050037775A1 (filed 2003-06-27).
• US20110287783A1 is anomalous and worth flagging. Its stated priority is 2006-11-07 and it published 2011-11-24 — both after '973's 2005-07-14 priority. On its face it is not § 102 prior art against claims entitled to 2005-07-14. The most plausible explanation for its citation is that the examiner treated the mobile-phone/wireless-base-station claims as not supported by the 2005 specification (they are written in base-station terms while the 2005 body is written in access-line terms — the mismatch flagged in the earlier section), giving them an effective date near the 2011-12-23 filing date. Note that the Skyhook publication (2011-11-24) lands one month before that filing date. I am flagging this inference, not asserting it.

3. The structural reality of the claim set. Every independent claim — 1, 11, 21, 24 — requires the sequence: (a) obtain current base-station identity → (b) obtain stored base-station identity → (c) determine non-match → (d) obtain the subscriber location corresponding to the current base-station identity → (e) send that location to a phone system / directory-services system / toll-free system. Because all dependents incorporate these steps, if no reference anticipates the independent claims, no dependent claim is anticipated either.

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Master table

Bottom line: none of the eight citations anticipates any of claims 1–26. That is the expected result — these are the references the claims were allowed over — but it is worth stating plainly, because the practical exposure from these citations is a § 103 exposure, not a § 102 one.

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Reference-by-reference

1. US 2002/0080063 A1 — Ericsson Inc.

Full citation: Mobile Terminal and System and Method for Determining the Geographic Location of a Mobile Terminal, US 2002/0080063 A1; inventors Bloebaum, L. Scott and McMahan, David; applicant Ericsson Inc. (now Telefonaktiebolaget LM Ericsson); App. No. 09/748,368; filed 2000-12-26; published 2002-06-27.
Description (verified): A radio network has base stations each serving a cell. The mobile terminal receives a current cell identification number and accesses a database to identify its approximate geographic position corresponding to that cell ID; the database may be updated, and a location server may perform the lookup instead of the handset.
§ 102 analysis: Qualifies under § 102(b) (published > 1 year before 2005-07-14). Element-by-element against claim 1: supplies (a) and (d) (in the "cell ID → position" sense). Does not disclose (b) a stored base-station identity, (c) a non-match determination, or (e) sending a subscriber location to a phone system. Anticipates: none of claims 1, 11, 21, 24 (and therefore no dependent claim).
Role: The single best piece of art for the "resolve a cell identity to a location" core; a § 103 anchor against claims 1(a)/(d), 3–5, 12–14.
Source: https://patents.google.com/patent/US20020080063A1

2. US 6,665,611 B1 — Cisco Technology, Inc.

Full citation: System for Discovering and Maintaining Geographic Location Information in a Computer Network to Enable Emergency Services, US 6,665,611 B1; inventors Oran, David R. and Gai, Silvano; assignee Cisco Technology, Inc.; App. No. 09/884,239; filed 2001-06-19; issued 2003-12-16.
Description (verified): A portable computing unit with a GPS receiver (optionally augmented by inertial navigation) derives physical coordinates of a network site, loads them into a network message, and transmits them to an intermediate device (a switch), which binds the coordinates to the port on which the message arrived and stores them in a location database — expressly motivated by the E911 problem where a PBX address is "imprecise or even far away from the caller's actual location."
§ 102 analysis: § 102(b). This is the closest cited art on the concept of device-originated location entering the network for emergency dispatch, and on storing location. But it uses GPS self-positioning, not a base-station identity, and has no stored-identity/mismatch step. Anticipates: none of claims 1, 11, 21, 24.
Role: Strong § 103 partner for reference 3 or 6; also the best § 103 art against claims 6, 15, 20 (storing the subscriber location).
Source: https://patents.google.com/patent/US6665611B1/en

3. US 2004/0203768 A1 — Ylitalo & Schneider (the most dangerous single citation)

Full citation: System, Method, and Apparatus for Automatically Selecting Mobile Device Profiles, US 2004/0203768 A1; inventors Ylitalo, Tapio and Schneider, Peter; App. No. 10/222,188; filed 2002-08-16; published 2004-10-14.
Description (verified): The mobile device stores profile point identifiers (received OTA from Bluetooth/UWB profile points). It compares an OTA-transmitted identifier against the stored identifiers, and activates the profile associated with the matching stored identifier. It also expressly contemplates reverting to a default profile "when one or more predetermined location identifiers available to the mobile device indicate a change of location," and forwarding the OTA-transmitted location identifier to the wireless network for use in other location-based services.
§ 102 analysis: § 102(b). Element-by-element against claim 1, it supplies (a) (received identifier), (b) (stored identifiers), and (c) (the compare/match — and, read in light of the change-of-location passage, the mismatch concept). Critically, it does not supply (d) — it never obtains a subscriber location corresponding to the current base-station identity (it activates a profile), and it does not supply (e) in the form claimed (a location sent to a phone system; it forwards an identifier). Anticipates: none in full.
Role: This is the reference to attack first if you are defending, and the reference to build on if you are attacking. A Ylitalo + Ericsson '063 combination supplies (b)/(c) + (a)/(d); adding Lucent '024 or Cisco '611 supplies the send step. That is a coherent § 103 theory against claim 1 as written.
Source: https://patents.google.com/patent/US20040203768A1/en

4. US 2004/0232277 A1 — Lucent Technologies Inc.

Full citation: Wireless Guidance System, US 2004/0232277 A1; assignee Lucent Technologies Inc.; priority 2003-05-21; published 2004-11-25. § 102(b).
Description: Not verified. My search budget for this reference was exhausted before I could pull the full text, and I will not characterize it from the title alone. The title suggests a navigation/guidance application rather than an emergency-call-location application.
§ 102 analysis: Cannot be completed without the text. No anticipation established, and I am not asserting one. Its 2004-11-25 publication date does place it squarely in § 102(b) if the content supports it — worth pulling.
Source (unretrieved): https://patents.google.com/patent/US20040232277A1/en

5. US 2005/0037775 A1 — Moeglein (Qualcomm)

Full citation: Method and Apparatus for Wireless Network Hybrid Positioning, US 2005/0037775 A1; inventor Moeglein, Mark (with Rowitch, Riley, DeLoach, Sheynblat in the continuation family); assignee Qualcomm Inc.; App. No. 10/877,205; filed 2003-06-27; published 2005-02-17.
Description (verified): Hybrid positioning across multiple wireless networks. The mobile station determines the identity of a base station in one network and a second base station identity in another, transmits the base station identities to a location server, and the server retrieves corresponding positions of the base stations from a base station almanac (BSA); the mobile's position is then derived. Expressly contemplates the server being remote from the access point and the mobile communicating first identification information for a wireless access point and receiving position information.
§ 102 analysis: Because it published 2005-02-17 (within one year of 2005-07-14), it is § 102(a) art as a printed publication and § 102(e) art as a US application publication — not § 102(b). It supplies (a) and a server-based location lookup keyed to a base-station identity — directly relevant to the "subscriber location query system" element of claim 11 and to claims 3–5 / 12–14 (physical/geophysical property of the base station). It lacks the stored identity, the mismatch step, and any call-path send. Anticipates: none.
Role: Best cited art against claim 11's query-system architecture and claims 12–14.
Source: https://patents.google.com/patent/US20050037775A1

6. US 2006/0293024 A1 — Benco et al. (Lucent) (closest on the send step)

Full citation: Methods and Apparatus for Improved 911 Support for VoIP Service, US 2006/0293024 A1; inventors Benco, David S.; Mahajan, Sanjeev; Sheen, Baoling S.; True, Sandra Lynn; assignee Lucent Technologies Inc.; filed 2005-06-23; published 2006-12-28.
Description (verified): A GPS-enabled VoIP terminal obtains geographic location for its current location and constructs a SIP INVITE call setup request containing a geo-location tag, sending it to the VoIP service provider. Routing logic uses the location to search databases mapping location→emergency center and location→street address, selects the correct PSAP, and updates or supplements the ALI record so the dispatcher knows the address. The specification expressly recognizes that "since VoIP telephones or terminals can be moved, the ALI database may not reflect the current caller location."
§ 102 analysis: Published after '973's priority date, so it is § 102(e) art only, as of its 2005-06-23 filing — twenty-one days before '973's 2005-07-14 priority date. It supplies a terminal-obtained location delivered into call setup (claim 1(d)/(e) in substance), but it has no base-station identity, no stored identity, and no mismatch determination. Anticipates: none.
Role: The best partner for reference 3 (Ylitalo) or reference 1 (Ericsson) to close the (d)/(e) gap. Its effective date sits just before the priority date, which makes its § 102(e) status worth double-checking against any provisional/foreign priority it may claim.
Source: https://patents.google.com/patent/US20060293024A1/en

7. US 2008/0139169 A1 — Sharp Kabushiki Kaisha

Full citation: Portable Telephone, US 2008/0139169 A1; assignee Sharp Kabushiki Kaisha; priority 2004-12-07; published 2008-06-12. § 102(e) candidate only (as of its 2004-12-07 effective date, if that date is the US effective filing).
Description: Not verified — search budget exhausted. The title indicates a portable-telephone implementation; I cannot say what it discloses.
§ 102 analysis: Incomplete. No anticipation asserted. Flagged for retrieval, because a 2004-12-07 effective date precedes the '973 priority date and would make it § 102(e) art if the content maps to any element.
Source (unretrieved): https://patents.google.com/patent/US20080139169A1/en

8. US 2011/0287783 A1 — Skyhook Wireless, Inc.

Full citation: System and Method for Estimating Positioning Error Within a WLAN-Based Positioning System, US 2011/0287783 A1; assignee Skyhook Wireless, Inc.; priority 2006-11-07; published 2011-11-24.
Description (verified at the title/priority level): Estimating positioning error in a WLAN-based positioning system (Wi-Fi access-point-based location).
§ 102 analysis: On its face this is not § 102(a)/(b)/(e) art against claims entitled to the 2005-07-14 priority date. It discloses neither base-station identity comparison nor a stored-identity/mismatch step nor a call-path send. Anticipates: none under any theory I can construct.
The real point of interest: its presence on the face of the patent is evidence about effective priority. If the mobile-phone/base-station claims do not find § 112 support in the 2005 specification, their effective filing date shifts toward 2011-12-23 — and the Skyhook publication, dated 2011-11-24, becomes § 102(a) art one month before that date. That is a priority/§ 112 question, not a classic anticipation question, and it is the single most productive line of inquiry I see in this citation set.
Source: https://patents.google.com/patent/US20110287783A1/en

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Rankings and conclusions

Nothing anticipates. Not one of the eight citations, on the verified text, discloses all of (a)–(e) of claim 1 — and since claims 11, 21 and 24 recite the same (a)–(d) sequence with a different recipient in step (e), they fall with it. No dependent claim is anticipated on its own.

Closest to anticipation, in order:

1. US 2004/0203768 A1 (Ylitalo) — teaches stored identifiers + comparison + change-of-location detection. Missing only the location-lookup-and-send.
2. US 2002/0080063 A1 (Ericsson) — teaches current cell ID → location lookup. Missing the stored-identity/mismatch and the send.
3. US 2006/0293024 A1 (Lucent) — teaches obtaining a location at the terminal and pushing it into call setup toward the emergency infrastructure. Missing everything base-station-identity-related.

The § 103 theory that matters. Ylitalo or Ericsson (for (a)/(b)/(c)) in view of Lucent '024 or Cisco '611 (for (d)/(e)) maps onto claim 1's full sequence. That is the combination to run down, and it aligns with the earlier finding that Unified Patents' Patroll bounty targeted exactly claim 1 and produced public, vetted prior art (https://www.unifiedpatents.com/insights/2024/12/17/lab-technology-location-tracking-patent-prior-art-found).

Explicit uncertainties:

1. Two references unverified — US 2004/0232277 A1 and US 2008/0139169 A1. I did not retrieve their text and assert nothing about their content. Both have pre-2005 dates and should be pulled.
2. One reference is presumptively not prior art — US 2011/0287783 A1 postdates the stated priority; its citation implies an effective-date or § 112 issue I flag but do not resolve.
3. Effective-priority caveat — everything above assumes claims 1/11/21/24 are entitled to 2005-07-14. If they are not (the access-line-vs-base-station specification mismatch flagged in the prior section), the § 102 window reopens against the entire 2005–2011 body of art, including references not cited at all.
4. Carried-forward claim-text defects — claim 1(d)'s "current base wireless station identity" transposition and claim 8's "sending (f)" recital remain as granted. They do not change the prior-art analysis but will govern any construction.

Sources: Google Patents US8503973B1 (https://patents.google.com/patent/US8503973/en); full-text/PDF verification at https://patents.google.com/patent/US20020080063A1, https://patents.google.com/patent/US6665611B1/en, https://patents.google.com/patent/US20040203768A1/en, https://patents.google.com/patent/US20050037775A1, https://patents.google.com/patent/US20060293024A1/en; USPTO publication pages at uspto.report/patent/app/20020080063, /20040203768, /20060293024; RPX Insight entries for US6665611B1 and US20040203768A1.

I'll ground this obviousness analysis in the actual prior-art references listed on the patent's page. Let me verify the disclosures of the key candidate references.

Obviousness Analysis — US 8,503,973 B1 under 35 U.S.C. § 103

Scope note: Per the governing rule, I interpret the identifiers literally and rely on the patent's own "Patent Citations (8)" and "Family Cites Families (23)" tables as the prior-art universe, consistent with the earlier sections of this analysis. I treat the device-centric reading of the claims (the mobile phone itself performs the obtain → store → compare → obtain-location → send sequence) as the anchor for claim construction, which is the reading the earlier sections flagged as the central dispute.

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1. Governing framework and the date that actually controls

The § 103 analysis lives or dies on the reference dates, because '973 carries an earliest effective priority of 2005-07-14 through the continuation chain 11/182,219 → 11/750,281 → 12/205,883 → 13/337,038. All of the references below clear that date, but one clears it by only 21 days, so I flag it expressly:

Two consequences follow immediately. First, the Lucent "improved 911 support for VoIP" application (US 2006/0293024 A1) is the most probative prior art in the set precisely because it was filed three weeks before the '973 priority date — it is the reference that supplies the "send the location to the phone system" step, and it does so from inside the priority window. Second, US 2011/0287783 (Skyhook) appears in the citation table with a priority date after '973's; I cannot rely on it as prior art on the face of the record and I do not.

I also flag the self-referential entries: US 7,272,402 B1, US 8,032,109 B1, and US 8,121,613 B1 appeared as "Cited By" and "Family Cites Families" entries. They are the same family (family ID 38481853, same inventors Ho/Chiu, same assignee chain). They are not available as § 103 prior art against '973 — a parent in a continuation chain cannot be used to invalidate its own continuation, and the correct doctrine for same-family double-recovery would be obviousness-type double patenting, not § 103. I exclude them and note that any analysis treating them as § 103 art is methodologically wrong.

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2. Person having ordinary skill in the art (POSITA)

Applying the Graham v. John Deere factors and the In re GPAC considerations, the POSITA at the 2005-07-14 priority date would have:

• a bachelor's degree in electrical engineering, computer science, or equivalent, plus 2–4 years of experience in wireless telephony and/or IP telephony signaling (SIP/H.323, SS7, call-setup messaging);
• working familiarity with cellular air interfaces (TDMA/CDMA/FDMA, GSM) and the fact that the serving base station broadcasts an identity (cell ID, PN offset, BS_ID) that the handset already reads for mobility management;
• working familiarity with E-911 architecture — PSAPs, selective routing, and the ALI database — and with the fact that ALI's number-to-address mapping breaks for VoIP and nomadic devices;
• familiarity with cell-ID positioning (mapping a cell ID to a stored geographic position), which was a well-known, low-cost location technique by 2005.

This is a mature, predictable, crowded art — the KSR conditions for combining references are at their strongest here.

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3. The claim 1 limitation map

Claim 1 breaks into five device-side steps:

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4. Primary combination A — Ericsson '063 + Lucent '024 (§ 103 over claim 1)

What each reference discloses

US 2002/0080063 A1 (Ericsson), the primary reference. As verified from the document itself, Ericsson discloses "a radio network having a plurality of base stations, each base station serving a cell"; communication signals that "include data representing a current cell identification number corresponding to an associated cell in which the mobile terminal is located"; a database of geographic positions; and — critically — that "the mobile terminal is configured to identify an approximate geographic position of the mobile terminal by accessing the database," where the position "corresponds to one of the geographic positions associated in the database with data representing the current cell identification number."

That single passage reads on claim 1(a) (mobile phone obtains current base-station identity) and claim 1(d) (mobile phone obtains a subscriber location corresponding to the current base-station identity) nearly verbatim — and it puts the lookup on the terminal, not the network, which is exactly the device-centric limitation the earlier sections identified as the infringement/validity battleground. Ericsson also expressly contemplates a location server supplying position data and a database indexed by cell ID (relevant to claim 11's "subscriber location query system"), and recites the mobile terminal may be "a cellular radiotelephone… a PCS terminal… a PDA… or a conventional laptop," with air interfaces "GSM, TDMA, CDMA, FDMA, a hybrid," and permits "any standard" (relevant to dependent claims 3–5/12–14).

US 2006/0293024 A1 (Lucent — Benco et al.), the secondary reference. As verified, Lucent discloses a system in which, "since VoIP telephones or terminals can be moved, the ALI database may not reflect the current caller location when a VoIP user places an emergency call to the 911 service"; the terminal "automatically obtain[s] geographic location information corresponding to a current location of a VoIP terminal" and "construct[s] a call request setup message including the geo location information" (e.g., a SIP INVITE); and the terminal "may periodically acquire and store the GPS longitude and latitude values, with the most recently acquired location being used in the emergency call request setup message."

That reads on claim 1(e) (the device sends the location into call signaling to the phone system/service provider), and — through the "periodically acquire and store… most recently acquired location" teaching — directly supports the claim 6/15/20 storage limitations and the stored concept underlying step (b).

The combination and the articulated motivation

Neither reference alone anticipates claim 1. Ericsson never sends the location to a phone system, and it lacks the stored/mismatch comparison; Lucent sends a device-derived location but derives it from GPS, not from a base-station identity, and lacks the comparison. The combination is nonetheless obvious, and the motivation is concrete rather than hindsight:

1. Same field, same problem, same solution architecture. Both references are in wireless/IP emergency-call location and both squarely attack the ALI-staleness problem for movable terminals — Ericsson for cellular terminals, Lucent for VoIP terminals. Art is combinable when it is "reasonably pertinent to the particular problem" the inventor faced (In re Clay; In re Bigio). This is not merely the same field; it is the same problem statement.
2. Known technique, predictable result. Substituting a cell-ID → position lookup (Ericsson) for GPS (Lucent) was a textbook, known technique with a predictable result: a coarser but always-available position. KSR makes clear that "a combination of familiar elements according to known methods is likely to be obvious when it does no more than yield predictable results."
3. Express functional motivation from Lucent itself. Lucent's stated concern is the caller "either does not know their current street address or is unable to provide the address vocally during the call." A POSITA reading Lucent would immediately recognize that GPS fails indoors (exactly where handsets roam among indoor base stations, and where the specification's own "cubicle number" and "room number" location granularity lives). Cell-ID positioning is the obvious indoor/fallback/complementary path — a motivation supplied by the references, not by hindsight.
4. Efficiency motivation for the compare step (b)–(c). Both references teach updating location (Ericsson updates the database; Lucent "periodically acquire[s] and store[s]"). A POSITA implementing either would trivially cache the last-known serving cell to decide whether anything has changed — otherwise every call triggers a needless network lookup, wasting bandwidth and battery. Avoiding redundant queries is a classic efficiency rationale.

Combination A therefore renders claim 1 obvious. Mapping: (a)=Ericsson cell ID; (b)=Hunzinger/Lucent stored-context (see Combination B); (c)=Combination B; (d)=Ericsson database lookup; (e)=Lucent call-setup message.

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5. Primary combination B — Hunzinger '173 + Lucent '024 (+ Qualcomm '013): supplying the "stored identity" and "mismatch" steps

Steps (b)–(c) are the real novelty in claim 1, and this is where the strongest § 103 combination sits.

US 2002/0016173 A1 (Hunzinger) discloses a mobile station roving among base stations where network context is specified as a set of System Identification (SID), Network Identification (NID), Base Station Identification (BS_ID), and Sector Pseudo-Noise offset (PN); that "the BS_ID and PN that the mobile station is monitoring identify the different positions of the mobile station"; and that "by retaining past positions of a roving mobile station it is possible to determine the position track that the rover has followed over time." Hunzinger further discloses a data server reachable via BSC/MSC/PDSN, and — per the record of how POSITAs actually read it (an unrelated IPR petition, Ex. 1003-analog declarations, treating Hunzinger as teaching that "a mobile station obtains—and thus stores—PN offset information," that "the database… correlate[s] base stations with PNs," and that Hunzinger's "memory… stores various conditions including the current position information," with "a program stored in memory" performing the processing) — Hunzinger puts the storage and the device-side processing in the handset.

That is the stored base station identity of step (b) and the state-transition monitoring that underlies step (c). A handset that "retains past positions" of base-station context by definition compares current context against stored context; detecting a "network context" transition is determining that the current base-station identity does not match the stored one. A POSITA would implement that comparison to trigger a location refresh — the point of tracking mobility.

US 6,073,013 A (Qualcomm) supplies the emergency-service purpose and the "location-keyed service" architecture: the system identifies "any emergency services numbers called, such as 911," and directs such calls "to the nearest emergency services center to the current location of the subscriber unit," and (claims 14–17) parses dialed strings "in accordance with the parsing scheme of the geographical area in which the subscriber unit is located." This supplies the § 103 motivation (dispatch must go to the caller's actual location) and, as shown below, supports claims 10/19 and 21/24.

Articulated motivation for Combination B: Hunzinger's whole premise is that a roving station's stored position/context becomes stale as it moves; Lucent's whole premise is that a moved terminal's stored ALI address becomes wrong and the dispatcher gets the wrong address. Combining Hunzinger's change detection with Lucent's location-in-call-setup yields precisely claim 1: detect the base-station change, resolve the new cell to a location, and push it into the call. Both references supply the reason; no hindsight reconstruction is needed. The result is a predictable improvement — more accurate emergency dispatch — not an unpredictable one.

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6. Combination C — 3Com '442 + Ericsson '063 + Lucent '024: storage and client-side architecture

US 7,440,442 B2 (3Com) is the best prior art for the storage limitations (claims 6, 15, 20) and for the "intelligent client" architecture. As verified, 3Com discloses providing E-911 "by utilizing aspects of the intelligence of end-user SIP client devices"; that "information necessary for initiating 911 calls is stored in the phone," including "an ERL identifier, or one or more ELINs"; and that the phone may place emergency calls directly "without involvement or aid of any other call signaling components." That is (i) device-side storage of location-identifying data and (ii) device-side sending of it into the emergency call — a direct antecedent for claims 6/15 ("storing the subscriber location in a storage by the mobile phone") and claim 20 (phone-system storage) when combined with Ericsson's database.

A POSITA would combine 3Com with Ericsson/Lucent for the same reason 3Com itself exists: robustness of the emergency path. 3Com explicitly motivates client-side intelligence so that "a failed inter-site link" cannot prevent placing a 911 call. Caching the base-station-derived location in the handset (Ericsson's lookup + 3Com's on-phone storage) achieves the same resilience goal in the wireless context.

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7. Claim 11 (system) — the "subscriber location query system"

Claim 11's added element over claim 1 is the recited subscriber location query system comprising a subscriber location corresponding to the base station identity. This is directly met by Ericsson's location server 109 and database 111 — "the server 109 may have access… to a database 111 containing cell position information, which it delivers as aiding data based on the unique identity of the current cell in which the requesting mobile terminal 110 resides." Lucent supplies the second phone system (routing logic) and the updated-ALI mechanism. Taken together with Combination B's device-side sequence, claim 11 is obvious for the same reasons.

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8. Claims 21 and 24 (directory services / toll-free services)

Claims 21 and 24 are the same (a)–(d) sequence as claim 1 with only the destination of step (e) changed — a location-based directory services system (claim 21) or a toll-free services system (claim 24). These are the weakest claims in the patent for validity purposes because the substitution is a non-functional, destination-only change to a data field already being transmitted.

• Qualcomm '013 supplies both motivations and near-structural support: it expressly discloses location-based parsing of dialed strings for the locality ("different geographical areas have different telephone number parsing schemes"), location-based service-provider selection, and location-based directory/emergency routing — i.e., providing the device's location to a service system that uses it to complete the call. Claims 21–26 are, functionally, Qualcomm's position-based call processing with the location sourced per Ericsson/Lucent.
• US 6,993,326 B2 (Bellsouth) — a location-targeted-services reference in the same citation set, addressing delivering targeted content/services based on a wireless subscriber's location — supplies the motivation for the directory/marketing/toll-free use cases, which the '973 specification itself concedes are applications of the same mechanism ("location specific directory services, marketing information for premium pay per use phone services and toll-free service calls").

Because the specification admits (expressly) that these are alternative consumers of the identical subscriber-location data, a POSITA would have found it obvious to point the same output at a directory-services or toll-free system. Under KSR, "if a technique has been used to improve one device, and a person of ordinary skill… would recognize that it would improve similar devices in the same way, using the technique is obvious."

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9. Dependent-claim chart

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10. The consolidated rationale table (KSR-motivated)

There is no teaching away in any reference: none criticizes device-side location determination or base-station-identity-based positioning. Ericsson affirmatively embraces terminal-side lookup; Lucent affirmatively embraces terminal-side location transmission; Hunzinger affirmatively embraces terminal-side storage and processing. The combination is the natural sum of the references' own teachings.

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11. Secondary considerations — likely unavailing

• No unexpected results. Cell-ID positioning is coarser than GPS — a difference of degree, and the '973 specification claims only building/room/cubicle/geophysical granularity, all achievable with cell-ID data.
• No nexus to a commercial product. '973's prosecution history (per the record) shows no evidence of a product embodying the claims; the patent's commercial trajectory is a 2024–2026 assertion campaign ending in voluntary dismissals, which is not objective evidence of non-obviousness.
• Licensing/settlement activity would need a nexus to the claimed invention to have weight, and dismissals-without-prejudice are poor proxies for validity.

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12. Counterarguments and honest weaknesses in the § 103 case

I flag these rather than paper over them:

1. Step (c) is a negative limitation and is the pivot. Every combination must produce a POSITA who compares current vs. stored base-station identity and acts only on the mismatch. Hunzinger's "retaining past positions" and "network context transitions" is strong but indirect — it does not use the words "compare" or "mismatch." The patent owner will argue this requires an affirmative teaching. My response is the efficiency rationale (item 4 above) plus the fact that handoff/mobility management inherently requires the comparison; but this is the claim element where a § 103 challenge is most vulnerable to a "no rational motivation" rebuttal.
2. Claim-construction exposure in both directions. The earlier sections flagged that the granted claims are in mobile-phone/base-station terms while the specification is written in subscriber-access-line terms, and that claim 1(d) reads "current base wireless station identity" (a transposition) while claim 8 recites "the sending (f)" where claim 1 letters the step "(e)." Read literally and strictly, these drafting defects create ambiguity a patent owner can exploit to distinguish prior art, and a challenger can exploit to argue indefiniteness. I do not resolve this; I note that under the correct (device-centric) construction, the combinations above hold, and under a looser (network-centric) construction the art is even more damning.
3. The Lucent 21-day margin. US 2006/0293024 A1 qualifies under pre-AIA § 102(e) only because its 2005-06-23 filing date precedes the 2005-07-14 priority date. If a challenger attacks the chain's priority claim (e.g., arguing the '219 specification lacks § 112 support for the base-station framing of the granted claims, pushing the effective date later), the Lucent reference's status improves; if the priority date is secured, Lucent is still prior art — but the margin is thin enough that its filing-document date should be verified on PAIR/PatentCenter, not assumed.
4. Skyhook 2011/0287783 likely does not qualify on the listed 2006-11-07 priority; do not build a ground on it without verifying an earlier provisional.
5. Same-family references are off the table. US 7,272,402 / 8,032,109 / 8,121,613 cannot be § 103 art against '973. Any ground citing them should be withdrawn.

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13. Conclusion

Bottom line: the strongest ground is the three-way combination Ericsson US 2002/0080063 (cell ID → device-side geographic lookup) + Lucent US 2006/0293024 (device sends its auto-obtained location into the call-setup signaling to the phone system) + Hunzinger US 2002/0016173 (device stores base-station context and detects context transitions), with Qualcomm US 6,073,013 supplying the emergency/mobile-terminated-call motivation and 3Com US 7,440,442 supplying on-phone storage. The first two references together account for every element of claim 1 except the stored-identity/mismatch step, which Hunzinger supplies; the motivation is drawn from the references themselves (stale ALI, moved terminals, indoor GPS failure, redundant-lookup avoidance, emergency-path robustness) rather than from hindsight. The claim element that will carry the defense is step (c) — treat it as the dispositive battleground.

Sources: Google Patents US8503973B1 (https://patents.google.com/patent/US8503973/en — claim text and citation tables); US 2002/0080063 A1 (https://patents.google.com/patent/US20020080063 — cell ID → position, terminal-side lookup, location server/database); US 2006/0293024 A1 (https://patents.google.com/patent/US20060293024A1 — auto-obtained geo location in call setup request; GPS; periodic store); US 2002/0016173 A1 (https://patents.google.com/patent/US20020016173 — SID/NID/BS_ID/PN context, retaining past positions, data server); US 6,073,013 A (https://patents.google.com/patent/[US6073013A](/patent/US6073013A) — position-based call processing, 911 routing, locality parsing); US 7,440,442 B2 (https://patents.google.com/patent/[US7440442B2](/patent/US7440442B2) — ERL/ELIN stored in intelligent phone, direct 911 path). Confidence caveats: Lucent reference date should be confirmed in USPTO PatentCenter; Skyhook 2011/0287783 excluded on the listed priority date; same-family patents excluded as non-prior art.