US 7979066

I'll run several targeted searches against USPTO, CAFC docket, and litigation sources for this specific patent number.

Let me check the CAFC docket records and PTAB/IPR activity specifically involving the '066 patent.

US 7,979,066 B2 — "Multiple IMSI connections"

Sourcing note: The bibliographic data below comes from the granted patent front page (US7979066 PDF), Google Patents, and third-party litigation databases. Where sources disagree, I flag it rather than resolve it. Notably, I found no Court of Appeals for the Federal Circuit 2026 docket in which U.S. Patent No. 7,979,066 is the patent on appeal. Details on that below.

Bibliographic data

Assignment/ownership events of record (as summarized by Google Patents): assignment from Pan to Lemko (effective 2008‑09‑24); a covenant not to sue recorded in favor of Motorola Solutions, Inc. (2012‑02‑21); and a patent security agreement recorded 2025 in favor of Piccadilly Patent Funding LLC, as security holder.

Abstract (verbatim)

"A system is disclosed that includes a first multiple International Mobile Subscriber Identity (IMSI) location register (MILR) module. The first MILR module includes user information associated with a plurality of mobile subscribers. For each of the mobile subscribers, the user information includes a first IMSI number and a first Mobile Directory Number (MDN). The first IMSI number and the first MDN are associated with a first country. The user information includes a second IMSI number and a second MDN. The second IMSI number and the second MDN are associated with a second country. The user information also includes active location information for each of the mobile subscribers."

Plain-language overview of the independent claims

There are exactly two independent claims — claim 1 (system) and claim 14 (method). The remainder (2–13, 15–21) are dependent.

Claim 1 — System. A system made up of four cooperating registers: a home location register (HLR) module, a visitor location register (VLR) module, a community location register (CLR) module, and a multiple-IMSI location register (MILR) module. The MILR holds, for each of multiple subscribers, a pair of identities — a first IMSI + first MDN tied to a first country, and a second IMSI + second MDN tied to a second country — plus active location information. The claim's distinguishing hook is the last "wherein" clause: whichever country the subscriber is currently in, both directory numbers remain "active local telephone numbers" in their respective countries, while only the IMSI matching the subscriber's current country is active. So a caller in country A can dial the country‑A local number and reach a subscriber who is physically in country B, without the roaming leg being billed as an international call.

Claim 14 — Method of routing calls from a first country to a second country via an IP network. Steps: (1) receive a telephone call to a first MDN in the first country; (2) determine the location of the mobile subscriber associated with both the first and second MDNs — selecting the first IMSI as active when the subscriber is in the first country, and the second IMSI as active when the subscriber is in the second country, with both MDNs remaining active local numbers in their own countries; and (3) when the subscriber is in the second country, route the call to the second country over the IP network.

Notable dependents worth flagging:

• Claim 3 places all four registers on a distributed mobile architecture (DMA) server in the first country; claim 4 adds a second DMA server in the second country; claim 5 gives the second server its own MILR.
• Claim 7 extends the scheme to three countries, with the third IMSI active and all three MDNs remaining locally dialable.
• Claim 12 covers outgoing calls from the first MDN to a phone in the second country; claim 13 the mirror-image incoming case via the IP network.
• Claim 18 stores the IMSIs on a SIM card; claim 20 recites "flat roaming over countries (FroC)"; claim 21 recites automatic selection of an IMSI based on the subscriber's active location.
• Claims 8–11 recite the MCC/MNC digit structure (first three digits = mobile country code; second three digits = mobile network code).

Litigation / PTAB posture (as of April 26, 2026)

• Lemko Corporation v. AT&T Inc. et al, No. 2:25‑cv‑00305‑JRG (E.D. Tex., filed March 17, 2025). U.S. 7,979,066 is one of seven asserted Lemko patents (alongside 7,840,230; 8,224,322; 8,310,990; 8,340,667; 8,359,029; 9,198,020). Accused products: AT&T Private Edge 5G Network and AT&T Private Mobile Connection. Assigned to District Judge Rodney Gilstrap.
• On March 6, 2026, Judge Gilstrap denied AT&T's motion to transfer venue to the Northern District of Texas under the first-to-file rule (Doc. 79, Memorandum Opinion and Order). That order discusses the parallel case Lemko Corp. v. [Microsoft Corp.](/litigations/by-plaintiff/Microsoft%20Corp.) et al, No. 3:22‑cv‑363‑K (N.D. Tex.) concerning a different set of Lemko patents.
• Infringement theories pleaded in the AT&T complaint map the '066 claim terms ("HLR module," "VLR module," "CLR module," "MILR module") onto 5G core functions such as UDM, UDR, AMF, SMF, AUSF and UPF — meaning claim-construction/eligibility disputes over whether 5G network functions meet 2G/3G-era structural limitations are the likely battleground.
• A parallel PTAB proceeding, IPR2025‑01142, was filed by Microsoft and AT&T Services against U.S. 8,310,990 — not the '066 patent. Lemko filed a Patent Owner's Request for Discretionary Denial invoking Fintiv and § 325(d).

CAFC 2026 docket check — result

The only 2026 Federal Circuit Lemko proceeding I located is Lemko Corp. v. Microsoft Corporation, No. 2024‑2336, decided by Rule 36 judgment (affirmed) on April 10, 2026 (per curiam: Hughes and Stoll, Circuit Judges, and Seeborg, Chief District Judge). That appeal arises from IPR2023‑00531 and concerns the Microsoft/Affirmed Networks patent set — it does not name U.S. 7,979,066. I therefore found no CAFC docket in 2026 in which the '066 patent itself is the subject of the appeal.

Explicit uncertainties

1. Priority date conflict: Google Patents and the patent itself show filing/priority of 2008‑09‑25, while Unified Patents' record for publication US‑20100075668‑A1 shows 2008‑09‑24 (likely reflecting the assignment effective date of 2008‑09‑24 rather than the statutory filing date). I have not verified this against USPTO PatentCenter directly.
2. CAFC coverage: Absence of a 2026 CAFC docket for the '066 patent is based on the search results I retrieved; I was not able to complete an exhaustive PACER/CAFC docket sweep in this session, so treat "no CAFC appeal found" as a search result, not a definitive negative.
3. Current ownership: The Google Patents record lists a security-holder interest (Piccadilly Patent Funding LLC) and an earlier Motorola Solutions covenant not to sue. "Current assignee" fields in these databases are explicitly disclaimed as assumptions by the source; a live USPTO assignment search would be needed to confirm the present owner of record.
4. I did not obtain a live USPTO PatentCenter/Patent Public Search confirmation of the issued claims in this session; the claim text I summarized is from the granted patent document as rendered on Google Patents and RPX/Insight.

I'll research litigation involving US patent 7979066. Let me start with several targeted searches.

The general searches returned unrelated noise. Let me target the specific case referenced on the patent page and Lemko's litigation history.

Based on my research, here is what I found regarding litigation involving US Patent 7,979,066 ("Multiple IMSI connections," Lemko Corp., sole named inventor ShaoWei Pan).

Confirmed Litigation Asserting US 7,979,066

1. Lemko Corporation v. AT&T Inc., et al.

• Plaintiff: Lemko Corporation
• Defendants: AT&T Inc.; AT&T Enterprises LLC; AT&T Communications LLC; AT&T Mobility LLC; AT&T Mobility LLC II; AT&T Services, Inc.
• Jurisdiction: U.S. District Court for the Eastern District of Texas (Marshall Division)
• Case Number: 2:25-cv-00305 (2:25-cv-00305-JRG)
• Filing Date: March 17, 2025
• Presiding Judge: Rodney Gilstrap
• Accused Products: AT&T's Private Edge 5G Network platform and AT&T Private Mobile Connection service
• Patents Asserted (7 total): U.S. 7,840,230; 7,979,066; 8,224,322; 8,310,990; 8,340,667; 8,359,029; 9,198,020
• Current Status (as of April 2026): Open / active. Defendants' motion to transfer venue to the Northern District of Texas (under the first-to-file rule, arguing overlap with Lemko Corp. v. [Microsoft Corp.](/litigations/by-plaintiff/Microsoft%20Corp.), No. 3:22-cv-363-K (N.D. Tex.)) was denied by Judge Gilstrap in a Memorandum Opinion and Order (Doc. 79) signed March 6, 2026. Initial answer deadlines were extended to May 26, 2025.

Source links:

• Docket: https://dockets.justia.com/docket/texas/txedce/2:2025cv00305/[236690](/patent/236690)
• Venue order: https://law.justia.com/cases/federal/district-courts/texas/txedce/2:2025cv00305/236690/79/
• Complaint/claim-chart analysis: https://ai-lab.exparte.com/case/dct/txed/2:25-cv-00305/doc/analysis/1
• Litigation news (RPX): https://litigation.rpxcorp.com/news/85618-at-t-hit-in-lemko-s-edge-computing-campaign
• Patent-family litigation flag: https://portal.unifiedpatents.com/litigation/Texas%20Eastern%20District%20Court/case/2%3A25-cv-00305

For the '066 patent specifically, Lemko's infringement theory (E.D. Tex. complaint) maps independent claim 1's legacy 2G/3G "HLR module / VLR module / community location register (CLR) module" limitations onto AT&T's 5G network functions (UDM/UDR/AMF/SMF/AUSF/UPF), with the "community location register" function allegedly met by HLR information being common between servers in different locations.

Related/IPR Activity (same patent family campaign; not necessarily the '066 patent itself)

• Lemko Corp. v. Microsoft Corp. (Affirmed Networks), No. 3:22-cv-363-K (N.D. Tex.) — filed February 14, 2022. This case asserts eight different Lemko patents (7,548,763; 7,653,414; 7,855,988; 8,107,409; 8,688,111; 9,191,980; 9,332,478; 9,755,931) — the '066 patent was NOT asserted here. Long mired in motions to dismiss.
• IPR proceedings: I identified PTAB activity captioned IPR2025-01142 (U.S. Patent No. 8,310,990) with AT&T as petitioner, in which Lemko sought discretionary denial (Fintiv). Note: this is the '990 patent, one of the family members co-asserted with '066, not the '066 patent itself. I did not find a confirmed IPR specifically challenging the '066 patent.
• A separate Lemko Corp. v. Microsoft Corp. matter appearing as No. 3:26-cv-01876 (N.D. Tex.) with a reported June 2026 filing date was visible in a case-index listing, but I could not confirm whether the '066 patent is asserted in it, so I do not treat it as a '066 case.

Key caveats and confidence

• Only one district court case could be affirmatively tied to assertion of the '066 patent: Lemko v. AT&T, 2:25-cv-00305 (E.D. Tex.).
• I found no CAFC appeal specifically involving the '066 patent, and no earlier (2011–2024) litigation asserting the '066 patent.
• Note the USPTO assignment record: in 2012 Lemko granted Motorola Solutions, Inc. a covenant not to sue (recorded per the patent page), and in 2025 a patent security agreement to Piccadilly Patent Funding LLC as security holder — these are not litigation but affect enforceability/ownership posture.
• My searches were limited to public web sources (Justia, Dockets, RPX, Mondaq, Ex Parte AI-Lab, Unified Patents, USPTO PTAB filings). PACER/CAFC dockets were not directly queried, so there could be additional suits, additional asserted claims, or supplementary proceedings (e.g., IPRs filed after my search) that are not reflected here. I did not find any such additional '066-specific cases.

Bottom line: The only known litigation asserting US 7,979,066 is Lemko Corporation v. AT&T Inc. et al., Case No. 2:25-cv-00305, E.D. Tex. (filed March 17, 2025, Judge Gilstrap), currently open, with a March 6, 2026 order denying transfer to N.D. Tex.

I'll start by verifying the structured "no proceedings" signal with targeted searches across PTAB and litigation sources.

Let me dig specifically for any IPR naming the '066 patent, and check the recent AT&T/Lemko PTAB activity.

Let me search for any PTAB challenge specifically targeting the '066 patent or its continuation-family members.

Proceedings overview

Total AIA trial proceedings on US 7,979,066: zero. The structured "PTAB proceedings on file" block — the canonical USPTO Open Data Portal list — returns no IPR, PGR, or CBM naming this patent, and my independent searches surfaced none either. There is therefore no claims-invalidated / claims-sustained / settled / institution-denied breakdown to report for the '066: no claim of this patent has ever been tested at the Board, no claim has been canceled, and no estoppel has attached.

Bottom line defensive posture: the '066 is a "clean" patent with no PTAB paper trail — but that cuts both ways. Because no IPR was ever filed, (a) every claim (1–21) remains live and unadjudicated, (b) no § 315(e)(2) estoppel exists against anyone, and (c) a defendant still has the full universe of prior-art grounds available — including grounds a sibling-patent petitioner has already fully briefed and lost on. The patent is not hardened by victory at the Board; it is simply untested. That is a materially different risk profile from the Lemko sibling patents discussed below.

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Proceedings on US 7,979,066

None. I could not identify any IPR, PGR, CBM, or other AIA trial proceeding naming U.S. Patent 7,979,066 (nor its same-family continuations, U.S. 8,326,286 and U.S. 8,744,435) as the challenged patent. Google Patents' family page for the '066 shows no PTAB "litigation" entries — only the E.D. Tex. district-court case discussed below (US7979066B2).

Confidence caveat: this is a negative finding. The ODP block is authoritative for indexed proceedings, and I corroborated it with multiple searches, but a very recently filed petition (±weeks) could be unindexed. Treat "zero" as accurate as of 2026-09-29 pending a manual PTAB E2E docket check (https://ptacts.uspto.gov/).

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Adjacent PTAB activity you must not confuse with the '066

These proceedings target different Lemko patents in the same DMA/network-virtualization portfolio. They are relevant to strategy and estoppel, but they did not touch the '066 and did not cancel any '066 claim. I list them most-impactful first.

IPR2023-00531 — [Microsoft Corp.](/litigations/by-plaintiff/Microsoft%20Corp.) and Affirmed Networks, Inc. v. Lemko Corp. (U.S. 7,855,988)

• Type: Inter Partes Review
• Filed: ~2023-02 (Microsoft/Affirmed's 2023 wave against Lemko)
• Status: Final Written Decision issued; Lemko appealed
• Judge panel: not confirmed from my sources — verify on PTAB E2E
• Petition grounds: § 102 anticipation of claims 1, 3–9, and 20 of the '988 patent by U.S. Pub. No. 2007/0021120 A1 to Flore (a handover/PDP-context reference)
• Final Written Decision: per the '990 petition (which quotes it), the Board found "claims 1, 3–9, and 20 were anticipated based on U.S. Publication No. 2007/0021120 A1 to Flore" — Microsoft/Affirmed won this one. Source: Microsoft Corp. et al. v. Lemko Corp., IPR2023-00531, Paper No. 31 (PTAB Sept. 10, 2024) ("988 FWD"), cited at ptacts.uspto.gov petition 1558047.
• Appeal: Lemko Corp. v. Microsoft Corp., No. 24-2336 (Fed. Cir.) — Lemko's opening brief filed 2025-01-29 (cited as Ex.1009 in IPR2025-01142). Disposition not confirmed from my sources.
• Defensive value for the '066: low direct value — different claims, different scope. But it establishes that Flore-style handover art defeated Lemko once, which is a template challengers are actively reusing (see IPR2025-01142).

IPR2025-01142 — Microsoft Corp. and AT&T Services, Inc. v. Lemko Corp. (U.S. 8,310,990)

• Type: Inter Partes Review
• Filed: 2025-06-20
• Status: "Discretionary Denial" per a single aggregator source (ipverse/GreyB), listing an institution decision date of 2025-11-20 and a termination date. Medium confidence — corroborate on PTAB E2E. If accurate, this is a Lemko win via discretionary denial.
• Judge panel: not confirmed
• Petition grounds: § 102 anticipation of claims 1, 3–9 of the '990 patent by Flore — same reference, same Inter-AS-Anchor↔DMA-gateway mapping, expressly leveraged off the '988 FWD
• Institution decision: Lemko filed a Request for Discretionary Denial (dated 2025-09-08) invoking Fintiv factors and § 325(d), arguing AT&T had known of the technology since 2013 and waited >12 years (settled expectations), and that Microsoft was recycling arguments the Board had already rejected. Source: PO Request for Discretionary Denial, IPR2025-01142.
• Defensive value for the '066: meaningful pattern signal — the Microsoft/AT&T axis is filing serially against this portfolio and leaning on the one prior loss ('988). It has not yet aimed at the '066.

IPR2023-00529 (U.S. 7,653,414) and IPR2023-00530 (U.S. 7,548,763) — Microsoft Corp. and Affirmed Networks, Inc. v. Lemko Corp.

• Type: Inter Partes Reviews
• Filed: ~2023-02
• Status: Both proceeded to Patent Owner responses/declarations; Lemko argued its DMA/NFV architecture is not the legacy "network-in-a-box" art. My sources show the '763 POPR and the '414 Patent Owner Response (2023-12-21), but no confirmed FWD outcome for either. Do not assume a disposition.
• Defensive value for the '066: these are the "computer-readable-medium-can't-be-hardware" and "DMA" construction fights. They matter to the '066 only insofar as the '066's claim 1 also recites register modules — but the '066 was never in these proceedings.

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Strategic summary

Claim status of the '066. Every claim — 1–21 — is UNTESTED and live. There are no CANCELED claims (nothing was invalidated at the Board) and no claims SUSTAINED by a PTAB FWD (nothing was adjudicated). The only claim-level threats to date are the invalidation counterarguments that a challenger would borrow from the sibling-patent fights: the '988 FWD's holding that Flore anticipated the DMA-gateway claims, and the Lemko-favorable constructions on "computer-readable storage medium" vs. hardware appliances. Neither maps cleanly onto the '066's actual claim 1, which is directed to a MILR/HLR/VLR/CLR register stack storing per-subscriber country-specific IMSI + MDN pairs with active-location switching — a country-roaming identity claim, not a DMA-gateway-routing claim. The most obvious art family for a '066 challenge is the multiple-IMSI/multiple-MISDN literature cited on the face of the patent (e.g., Yue Jun's MIMM/MISM publications, Roamware, Ghost Telecom's plural-IMSI SIM work), none of which appears in any Lemko trial. That is a genuinely open attack surface.

Estoppel landscape. Because no IPR was ever filed on the '066, § 315(e)(2) estoppel is zero. No petitioner is barred from raising any ground against any '066 claim. Conversely, if you file and lose, you will be estopped as to every ground you raised or reasonably could have raised — so if IPR is on your roadmap, front-load your best art. The practical consequence: a defendant today can run the full § 102/§ 103 playbook on the '066 without inheriting any prior petitioner's estoppel shadow, and can also freely rely on Microsoft/AT&T's already-briefed Flore and NFV arguments as supporting authority without being a privy.

Pattern signals. Yes — same petitioner, multiple IPRs. Microsoft (with Affirmed Networks, then with AT&T Services) filed four-plus IPRs against Lemko's DMA portfolio, and the Board has landed on both sides (Microsoft won the '988; Lemko appears to have obtained discretionary denial on the '990). No defensive aggregator (e.g., Unified Patents) appears in the chain — the only Unified reference I found is a litigation-data page, not a filed petition. Lemko litigates aggressively and does not settle quietly: it has taken the '988 FWD to the Federal Circuit (No. 24-2336), so expect PTAB decisions in this portfolio to be litigated rather than traded away. Note also the 2025-03-25 security agreement to Piccadilly Patent Funding LLC — the patents are collateralized, which tends to harden the holder's incentive to monetize rather than settle cheap.

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Recommended next steps

1. If you have been asserted the '066 (or named in the Lemko campaign): the '066 is the least-fortified Lemko patent in the portfolio — it is the only one with no PTAB history. Commission a § 102/§ 103 search now centered on the multiple-IMSI/multiple-MISDN art of record (Yue Jun MIMM/MISM 2005/0070278 and 2005/0075106; Roamware 2007/0213075; Ghost Telecom WO2007102003A1) rather than the DMA-gateway art that failed/pending elsewhere. Those references were cited on the '066's face, which raises a § 325(d) risk you must neutralize with art that was not before the examiner.
2. Check the § 315(b) clock before planning any IPR. The '066 is asserted in Lemko Corp. v. AT&T Inc., No. 2:25-cv-00305 (E.D. Tex., Judge Gilstrap), alongside U.S. 7,840,230; 8,224,322; 8,310,990; 8,340,667; 8,359,029; 9,198,020 (Unified Patents docket; see also the complaint analysis at ai-lab.exparte.com and the Peter/AT&T campaign writeup at Mondaq). A § 315(b) bar attaches one year after service on a real party in interest — I could not confirm the service date, so verify it before assuming the window is open or closed.
3. If no '066 IPR exists and the bar has run: your remaining invalidity route is district-court § 282 (clear-and-convincing) plus Alice — and note Lemko has already litigated § 101 against Microsoft and survived a motion to dismiss on it (Lemko's 2025-04-15 press release), so lead with §§ 102/103, not eligibility.
4. Verify everything on primary sources before relying on it: pull the '066's PTAB E2E page at https://ptacts.uspto.gov/ (search patent number 7,979,066) and confirm the IPR2025-01142 status/date I flagged. Docket for the '988 appeal: Lemko Corp. v. Microsoft Corp., No. 24-2336 (Fed. Cir.) — check CourtListener for the disposition.
5. Watch the sibling decisions as free R&D. A Lemko loss in the pending '990 IPR (Microsoft/AT&T) or a Federal Circuit affirmance in No. 24-2336 would supply the challenger playbook; a Lemko win (e.g., the apparent discretionary denial) signals the Board will reward Lemko's "settled expectations / AT&T knew since 2013" narrative and should shape your framing away from serial-petition optics.

I'll research the assignment chain for US 7,979,066 from the primary and cross-reference sources.

Let me dig for the specific recorded assignment reel/frame entries and correspondents.

Ownership & Assignment Reconstruction — US 7,979,066 B2

Sourcing note / limitation up front. I was not able to retrieve the USPTO Assignment Center (reel/frame) records directly in this session; the Assignment Center and assignment.uspto.gov are not crawlable via the search tools I have, and no public mirror I could reach exposed the reel/frame numbers or the correspondent-of-record fields for this patent. Everything below is reconstructed from (a) the Google Patents "Legal Events" panel on the patent page itself (which surfaced the post-issuance reassignments), and (b) court records in the related Motorola and AT&T litigations. Where a field is unavailable I say so rather than fill it in. Reel/frame and correspondent fields are the two that I could not verify and should be pulled live from Assignment Center before this memo is relied on.

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Inventors

Unusual patterns — present, and material:

• Former-employer ownership attack timed to the filing. Pan had been a Motorola staff engineer (from Aug. 1994) promoted to Director of Advanced Technology & Development (~Sept. 2000), and left Motorola in late March 2004. Motorola, Inc. v. Lemko Corp. et al., No. 1:08-cv-05427 (N.D. Ill.), was filed in 2008 and sought a declaratory judgment that Motorola — not Lemko — was the rightful owner of eight Lemko patents and ten pending applications that "Pan and Labun obtained or filed and assigned to Lemko between 2004 and 2009." The case number (08-cv-05427) places the complaint in the same 2008 window in which the '066 application was filed (2008-09-25). This is the single most important ownership fact about this patent, and it is not a shell/NPE pattern; it is an original-title cloud later resolved contractually (see 2012 below).
• No inventor-departure pattern. The sole inventor is also the assignee's president/co-founder; he did not leave Lemko. The "all inventors departed within 12 months" heuristic does not apply.

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Original assignee

Lemko Corporation — the entity named on the issued patent.

• Entity: Illinois corporation, incorporated August 2, 2002 (per Mondaq case note; Lemko's own marketing says "founded 2004" — the 2002 incorporation date and the 2004 operational start are both supported by the record, and the discrepancy is resolved by the Motorola opinion, which notes defendants called pre-2004 Lemko an "unfunded shell of a company" with "no products, no sales and no patents" until H2 2004).
• Address of record: 1700 Golf Road, Schaumburg, IL 60173 (Lemko NTIA filing).
• Primary line of business: software-defined mobile network infrastructure — its "Distributed Mobile Architecture" (DMA) platform virtualizing core network functions (MSC/BSC/HLR/VLR/AAA) on off-the-shelf servers; marketed as Node1 and as private 4G/5G / mobile-edge-computing networks for rural broadband, public safety and IoT (Alaska, Northern Canada, Africa; Cairo, Illinois).
• Did it ship a product embodying the claims? Yes, claimed yes. Lemko pleads it complies with 35 U.S.C. § 287(a) by marking patent-practicing products with the Asserted Patents, and produced a representative patent-marking label identifying each asserted patent (including the '066) in Lemko Corp. v. AT&T, E.D. Tex. 2:25-cv-00305, Compl. ¶¶ 42–43.
• Current status: Operating. Actively litigating as plaintiff in 2025 (Lemko v. AT&T, filed 2025-03-17) and Lemko v. Microsoft/Affirmed Networks (N.D. Tex. 3:22-cv-00363, filed 2022). However, a patent security agreement recorded March 2025 in favor of "Piccadilly Patent Funding LLC, as security holder" indicates the portfolio has been pledged as collateral — a financing/encumbrance signal worth tracking. I found no evidence of a Lemko bankruptcy or dissolution.

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Assignment timeline

⚠️ Reel/frame numbers and correspondents could not be retrieved in this session. The three events below are confirmed by Google Patents "Legal Events" and by court documents; the executed dates for events 2 and 3 are not visible in the sources I reached (only the recording dates Google Patents displays). Do not treat the reel/frame or correspondent fields as populated — they are unknown here.

1. 2008-09-24 / executed ~2008-09-24 · recorded 2008-09-25 — Reel/frame: NOT RETRIEVED

• Conveyance: Assignment (assignment of assignors' interest)
• Assignor: ShaoWei Pan (sole inventor)
• Assignee: Lemko Corporation
• Correspondent: NOT RETRIEVED (patent's prosecution attorney of record is Toler Law Group per the front page; that is prosecution counsel, not a confirmed assignment correspondent — do not conflate them)
• Context: Foundational inventor-to-company assignment, executed the day before filing and recorded the day the application was filed; contemporaneous with Motorola's competing ownership claim.

2. executed ? · recorded 2012-02-21 — Reel/frame: NOT RETRIEVED

• Conveyance: Covenant Not to Sue (Google Patents renders this as an "Assigned to" event; the operative instrument is a covenant, i.e., a contractual non-assertion/limited license, not a transfer of title)
• Assignor: Lemko Corporation
• Assignee/beneficiary: Motorola Solutions, Inc.
• Correspondent: NOT RETRIEVED
• Context: Settlement artifact ending the Motorola ownership/trade-secret war — resolves the 2008 title cloud as to Motorola; reported to cover Lemko's '988 patent specifically (Mondaq), and Google Patents records a same-dated Motorola covenant event against the '066. Not a title transfer, and not a defensive-aggregator neutralization (Motorola is a single operating beneficiary, not RPX/AST/LOT).

3. executed ? · recorded 2025-03-25 — Reel/frame: NOT RETRIEVED

• Conveyance: Patent Security Agreement (lien / collateral pledge)
• Assignor / Grantor: Lemko Corporation
• Assignee / Grantee: Piccadilly Patent Funding LLC, as security holder
• Correspondent: NOT RETRIEVED
• Context: Securitization / financing — the portfolio is pledged as collateral for an obligation to a funding entity. This is a security interest, not an ownership transfer; title remains with Lemko. Note the recording date (2025-03-25) is eight days after Lemko filed the AT&T suit (2025-03-17), so this is not a pre-litigation transfer.
  • ⚠️ Do not conflate "Piccadilly Patent Funding LLC" with the Quest Patent Research Corporation / Peregrine Licensing LLC / QPRC Finance LLC family that appeared in one of my search hits — that securities filing involves a different set of patents and entities and I found no evidentiary link to Lemko or Piccadilly. Naming-similarity alone is not a finding.

Net record: three recorded events — one true assignment (inventor → Lemko, 2008); one covenant not to sue (Lemko → Motorola, 2012); one security agreement (Lemko → Piccadilly, 2025). Title has never left Lemko Corporation. There is no recorded transfer to a licensing-only LLC and no assignment to a known NPE.

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Timeline diagram

timeline
    title Ownership of US 7979066
    2002 : Lemko incorporated in Illinois
    2004 : Pan leaves Motorola
         : Pan joins Lemko as CTO
    2008 : Pan files application
         : Rights assigned to Lemko
         : Motorola sues claiming ownership
    2011 : Patent issued
    2012 : Covenant not to sue to Motorola
    2025 : Lemko sues AT&T
         : Security agreement to Piccadilly

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NPE / troll-pattern signals

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Verdict

Operating-company assertion.

Lemko Corporation is the assignee of record and has never transferred title — the record is the 2008-09-24/25 inventor assignment to Lemko, a 2012-02-21 covenant not to sue to Motorola Solutions (settlement of the 2008 ownership suit), and a 2025-03-25 security agreement to Piccadilly Patent Funding LLC (a collateral pledge, recorded after Lemko filed suit). Lemko pleads it marks its patent-practicing products with the '066 and asserts it against actual competitors (AT&T Private 5G Edge / Microsoft-Affirmed Azure Private 5G Core), which is the classic operating-company profile — not an NPE chain. The two caveats that keep this from being a clean "operating" call, and that should be tracked: (i) the 2012 Motorola covenant shows at least one industrial defendant has already been carved out, and (ii) the 2025 Piccadilly security interest encumbers the entire portfolio, which is a common precursor to a later monetization or transfer event.

Two data gaps that materially limit confidence: reel/frame numbers were not retrievable, and correspondents of record were not retrievable — signal #3 (repeat correspondent) is therefore unresolved, and it is the field most likely to change the picture if this portfolio is later sold.

Verification: USPTO Assignment Center — https://assignmentcenter.uspto.gov/ — and the indexed mirror https://assignment.uspto.gov/patent/index.html (search patent number 7979066). Cross-reference the Google Patents legal-events panel at https://patents.google.com/patent/US7979066/en.

I'll run targeted searches against the USPTO/patent databases to verify the '066 record and retrieve details on each cited reference.

I have detailed results on the key multiple-IMSI references. Let me pull the remaining cited references to complete the citation-by-citation analysis.

Prior-Art Analysis — U.S. Patent No. 7,979,066 B2 ("Multiple IMSI connections")

1. Record confirmation (USPTO / Google Patents)

US 7,979,066 B2, App. No. 12/238,269, filed September 25, 2008, granted July 12, 2011, inventor Shaowei Pan, assignee Lemko Corporation. Confirmed identically on Google Patents (https://patents.google.com/patent/US7979066/en) and in the granted-document text. The front page lists 11 U.S./PCT references under "Citations" — that list is the basis for the reference-by-reference analysis below. I did not auto-correct any number; all identifiers are reproduced as they appear in the record.

(Note: the previously generated summary already flagged the 2008‑09‑24 vs. 2008‑09‑25 priority-date discrepancy between Unified Patents and the patent. It is not repeated here, but it affects nothing below — the operative § 102 date is the Sept. 25, 2008 filing.)

2. Legal framework that governs the citation analysis

Because App. No. 12/238,269 was filed before March 16, 2013, the pre‑AIA version of 35 U.S.C. § 102 controls. Three consequences matter when grading each citation:

• § 102(b): a printed publication or patent dated more than one year before Sept. 25, 2008, i.e., before Sept. 25, 2007, is a statutory bar.
• § 102(a): publication/patenting before the invention date (≈ the filing date, absent a § 1.131 swearing-behind) is prior art.
• § 102(e): a U.S. patent application publication that was filed before the applicant's date of invention is prior art as of its filing/priority date, even if it published after Sept. 25, 2008.

A critical caveat up front: pre‑AIA § 102 anticipation requires a single reference to disclose every limitation, arranged as recited in the claim. Independent claim 1 requires the conjunctive combination of an HLR module + VLR module + CLR module + a multiple‑IMSI location register (MILR) — and, in the final "wherein," that both MDNs stay active local numbers while only the IMSI of the subscriber's current country is active. None of the eleven cited references, taken alone, discloses that specific register architecture. My candid assessment is therefore that these citations function principally as § 103 obviousness references, not clean § 102 anticipations of the independent claims. The dependent claims inherit that problem (a dependent claim can be anticipated only if the reference also meets the independent claim).

With that framing, here is the reference‑by‑reference mapping.

3. The eleven cited references

Family A — "Multiple IMSI / multiple MSISDN" roaming art (the most material)

Family B — Ghost Telecom "plural‑IMSI SIM" art

Family C — Lemko's own earlier distributed‑mobile‑architecture (DMA) art

Important ownership nuance: this reference shares the Lemko applicant/inventor lineage with the '066 patent. Under pre‑AIA § 103(c), commonly owned § 102(e)/(f)/(g) art is disqualified as prior art for obviousness — so its practical exposure is limited to a § 102(e) anticipation theory (and possible double‑patenting), not § 103. A live USPTO assignment/inventorship check would be needed to confirm common ownership at the relevant time; I did not complete that check.

Family D — Peripheral citations (billing, VoIP routing, roaming database, network selection)

4. Bottom line — the most relevant prior art and why

1. The Jiang / Roamware MIMM/SIMM references (nos. 1, 2, 6, 10) and the Ghost Telecom plural‑IMSI references (nos. 7, 9) are the most relevant prior art. Together they disclose virtually every functional concept the '066 patent relies on — a subscriber with multiple IMSIs and multiple directory numbers, one per country; local numbers in each country so callers avoid IDD charges; and automatic selection of the appropriate IMSI based on the subscriber's current location (Jiang US 2007/0213075 A1 states this expressly, and it is the direct antecedent of claim 21). They are the references an examiner or challenger would lead with.
2. None of the eleven references, standing alone, discloses the full independent‑claim architecture. Claim 1's conjunctive HLR + VLR + CLR + MILR register set (with the dual‑active‑MDN "wherein" clause) and claim 14's "route to the second country via the IP network" step are the features the cited art does not cleanly meet as a single reference. The multiple‑IMSI prior art uses signaling gateways / SS7 leased lines, and the IP‑network routing appears (in the cited set) mainly in the Nokia reference in an unrelated context. This is why I characterize the eleven citations as § 103 obviousness art rather than § 102 anticipations of claims 1 and 14.
3. Lemko's own earlier application (US 2007/0232267 A1, no. 8) supplies the DMA/HLR/VLR/CLR backdrop for dependent claims 3–6 and 15–16, but as commonly owned art it is largely shielded from § 103 by § 103(c).

5. Explicit caveats / uncertainties

• Anticipation vs. obviousness. I have stated plainly where each reference could bear on a claim; only nos. 1, 2, 6 (and arguably 7) rise to a plausible § 102 theory, and even then chiefly against the SIM/automatic‑selection dependents (18–21), not the independent claims.
• Date basis. Publication/filing dates above reflect the Google Patents citation table from the '066 record and the individual reference pages; I verified nos. 1, 2, 6, 7 in detail via live search but did not open a live USPTO PatentCenter/Public‑Search file for every one of the eleven.
• I could not retrieve fresh live records for nos. 3, 4, 5, 9, 10, 11 within this session (search budget exhausted); their rows rely on the '066 citation table and the reference data already retrieved. Treat the statutory‑basis tags for those as reasoned classifications, not file‑verified conclusions.
• Ownership check not performed. The § 103(c) common‑ownership point for no. 8 (and the Piccadilly/Motorola assignment events noted in the prior summary) would need a live USPTO assignment search to confirm.

Primary URLs: https://patents.google.com/patent/US7979066/en · https://patents.google.com/patent/US20050070278A1/en · https://patents.google.com/patent/US20050075106/en · https://patents.google.com/patent/US20070213075/en · https://patents.google.com/patent/WO2007102003A1

I'll ground this obviousness analysis in the actual prior-art references listed on the patent page. Let me pull details on the key references.

I have strong grounding on the key references. Let me pull details on the remaining cited references.

Obviousness Analysis — U.S. Patent No. 7,979,066 (35 U.S.C. § 103)

Building on the prior sections: This analysis assumes the claim construction and claim summaries already generated (two independent claims — system claim 1 and method claim 14 — plus dependents 2–13 and 15–21). I do not repeat the claim recitations. I focus on the prior-art references listed on the '066 page and on the combinations that would render the claims obvious.

Sourcing note / limitation: I worked from the abstracts, claim text, and specification excerpts of the cited references as retrieved from Google Patents, FreePatentsOnline, EPO publication server (EP1665838B1), and RPX/Insight. I did not obtain certified full-text copies of every reference from USPTO Patent Public Search in this session. Where a reference's disclosure is characterized below, the characterization is grounded in the retrieved text; where I could not verify a specific teaching, I say so.

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1. Level of ordinary skill and the proper analytical frame

A POSITA here is a telecommunications network engineer with ~3–5 years of experience in GSM/CDMA core-network signaling (SS7/MAP, HLR/VLR/GMSC), roaming architectures, and multi-IMSI SIM behavior — the person who would implement "local-number-for-roamers" services at a carrier or equipment vendor circa 2005–2007. That is confirmed by the ’066 field itself and by the fact that the cited art spans SS7 signaling gateways (Jiang/Roamware), SIM application toolkits (Ghost Telecom), and distributed softswitch cores (Lemko).

Critically, the ’066's own Background frames the problem as the known one — "calls to the roaming device are charged at international roaming rates, resulting in expensive calls." That concession matters: the problem the claims solve was already recognized and articulated in the art, which strengthens the obviousness case considerably.

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2. The core combination: Jiang MIMM + Lemko DMA

The single most damaging combination is US 2005/0070278 A1 (Jiang / Roamware, "MIMM") as primary reference, in view of US 2007/0232267 A1 (Pan / Lemko, "DMA").

2a. What Jiang MIMM discloses

US 2005/0070278 A1 (priority 2003‑08‑13, pub. 2005‑03‑31) is titled "Signaling gateway with multiple IMSI with multiple MSISDN (MIMM) service in a single SIM for multiple roaming partners." Its abstract: a SIM with "at least one IMSI and at least one MSISDN," used "while the user is in the user's home network and while the user is roaming in another network," where "one of a home MSISDN and a local MSISDN is used."

The specification text retrieved on the family member EP 1 665 838 B1 is decisive on the key limitation. Jiang expressly states two implementation approaches:

"a) The two operators co‑operate and build a Dual IMSI SIM card and use the IMSI of the country the user is currently in. This approach can include multiple IMSIs with multiple MSISDNs, or multiple IMSIs with a single MSISDN‑H…"

That sentence — use the IMSI of the country the user is currently in — maps almost verbatim onto claim 1's "wherein when the active location information indicates that the particular mobile subscriber is located in [country A/B], the [first/second] IMSI number is active."

Jiang further discloses (from the related continuation, US 2008/0293408 A1, claims 69 and 81):

"…all ISMIs and all MSISDNs available to the MIMM subscriber device are active at all times."

and the background states the goal plainly: subscribers "receive calls on both numbers (HPMN and FPMN) without swapping the SIM card," so that "local users can call them … without worrying about international IDD calls." That is precisely the ’066's dual-active-MDN limitation (both the first and second MDNs are "active local telephone number[s]" in their respective countries simultaneously).

Jiang also discloses a network-side register: the Signaling Gateway 100 "includes an HLR, a VLR, an SMSC, a Service Node, and a GMSC" and has access to a database 106 storing "MSISDN-H, MSISDN-F, out-roamer information." Its "Subscriber Data 402 … includes an HPMN MSISDN-H number, an IMSI-H, an IMSI-F, and any FPMN MSISDN-F number," and its "Roamer information 404" captures "VMSC, VLR … collected from both the VLR during updateLocation and the HLR." That is user information with paired IMSI+MDN and active location information — the substance of the MILR.

What Jiang does not clearly disclose: the specific combination of four named modules — an HLR module, a VLR module, a community location register (CLR) module, and a MILR module — resident on a distributed mobile architecture server. That gap is closed by the second reference.

2b. What Lemko '267 discloses

US 2007/0232267 A1 (Pan, priority 2006‑03‑29/30, pub. 2007‑10‑04; assigned to Lemko Corp.) is "System, method, and device for providing communications using a distributed mobile architecture." Its AAA module includes "a home location register," a "visitor location register," and "at least one community location register, wherein the at least one community location register includes information associated with a home location register of another distributed mobile architecture." Its system claim 27 recites first, second, and third DMA servers "coupled … via an Internet protocol network."

So Lemko '267 supplies: (i) the HLR module, (ii) the VLR module, (iii) the CLR module (the term is Lemko's own house term, and it appears in the '066 claim verbatim), (iv) the DMA-server host for these registers, and (v) the IP-network linkage between servers in different geographies.

Confirming the family context, Lemko's own PTAB filings describe its DMA as implementing "network functionality, such as MSC, BSC, and home location register (HLR) functionality … onto a computer-readable medium running on a standard server," with "multiple cellular nodes … linked via IP connections" (Lemko IPR2023‑00529 record, Ex. 1002 to US 7,653,414).

2c. Motivation to combine — and why it is strong

1. Same field, same problem. Both references address roaming subscribers who need local numbers in more than one country to avoid IDD charges. Jiang's Background ([0004]) and Lemko's DMA disclosures sit in the identical art.
2. Complementary, not overlapping, teachings. Jiang provides the subscriber-data model (paired country-specific IMSI/MDN + roaming location) and the rationale (dual-active local numbers on one SIM). Lemko provides the network architecture to host location registers and to route calls between geographically separated nodes over IP. A POSITA designing a multi-country local-number service would naturally place Jiang's multi-IMSI subscriber database into Lemko's DMA server alongside the HLR/VLR/CLR rather than build a new core.
3. The '066 is, structurally, the union of the applicant's own two lines of work. Lemko '267 is the applicant's own published application and is cited on the face of the '066. The combination does not require combining strangers in the art; it requires adding a country-keyed multi-IMSI register to a DMA AAA module — an engineering step, not an inventive leap.
4. Predictable result. The claimed advantage (calls to the home-country local number reach a subscriber physically abroad, routed over IP, without international rates) is exactly the result each reference independently seeks. There is no teaching away.

Conclusion (claims 1, 2, 3, 4, 5, 6): Obvious over Jiang '278 in view of Lemko '267. Claim 3 (all four registers on a first-country DMA server) is met by Lemko '267's AAA module; claim 4 (second DMA server in the second country) and claim 6 (routing the call from the first to the second DMA server via IP) are met by Lemko '267's multi-DMA/IP-network disclosure; claim 5 (second server with its own MILR) follows from Lemko's distributed-CLR scheme combined with Jiang's replicated subscriber data.

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3. The method claims (14–17)

Claim 14's steps are: (1) receive a call to a first MDN in the first country; (2) determine the subscriber's location and select the active IMSI by country, with both MDNs remaining active local numbers; (3) route the call to the second country over the IP network.

• Steps (1)–(2) are taught by Jiang '278 (dual-IMSI/dual-MDN SIM; "use the IMSI of the country the user is currently in"; Signaling Gateway SRI/PRN interrogation to locate the subscriber).
• Step (3) — routing to the second country via an IP network — is taught by Lemko '267 (calls routed between DMA servers over an IP network) and, independently, by US 2006/0142011 A1 (Nokia), "Method for the routing of communications to a voice over internet protocol terminal in a mobile communication system," which addresses VoIP-terminated routing in a mobile core.
• Claim 16's "first DMA server … to a second DMA server" limitation is again Lemko '267.

Conclusion: Claim 14 obvious over Jiang '278 + Lemko '267 (optionally further in view of Nokia '011 for the IP-routing limitation). Claims 15–17 obvious for the same reasons.

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4. Dependent claims

Claims 8–11 and 18–21 are the easiest to invalidate as a matter of law, because their elements are disclosed essentially verbatim in the Ghost Telecom and Roamware references.

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5. Additional secondary reference: Starhome (local number for roamers)

Although US 2007/0021118 A1 (Starhome, "Method and a system for providing fix-line local numbers to mobile roaming subscribers," priority 2005‑07‑25, pub. 2007‑01‑25) appears in the "Family Cites" list rather than the "Citations" list, it is squarely on-point for the "active local telephone number" concept: a visitor service node "assigns a fixed-line number to a universal identification of the roaming subscriber" and queries the home network "to determine a current roaming location," so the roamer gets "a single local number which can be used irrespective of which cellular network he is currently roaming in." It is useful as evidence that using a locally-dialable number that follows the roamer was known, and it reinforces motivation.

Also potentially relevant from the same list: WO 2007/112699 A1 (Huawei), "Method, device and system for realizing one card for multi-number service" (2006‑04‑06) — a "one card / multi‑number" teaching in the same vein.

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6. Strongest rebuttal arguments the patent owner would raise — and their weaknesses

1. "The prior art does not disclose a MILR module as a distinct register." Weak. The name of a module is not the invention; the claim's substance (per-subscriber paired country-keyed IMSI/MDN + active location) is disclosed by Jiang's Subscriber Data + Roamer Information. Naming a known database a "MILR" does not confer patentability.
2. "The art teaches swapping IMSIs, not keeping both MDNs locally active." The owner will lean on the claim's "both MDNs are active local telephone numbers" language. Jiang undercuts this: the whole point of MIMM is receiving calls on both the HPMN and FPMN numbers "without swapping the SIM card," and the SMN/SIMM variants expressly keep one number usable everywhere. This is the weakest link for the patent owner.
3. "Secondary considerations — long-felt need and commercial success (DMA deployments, litigation value)." These must be tied to the claimed invention, not to Lemko's overall DMA platform. The ’066's claimed feature (dual-active local numbers with IP routing) was already being marketed by Roamware/Truphone-class services; nexus will be hard to establish.
4. § 112 / § 101 defenses. Not § 103, but worth flagging: the claim terms "MILR module," "CLR module," and "active local telephone number" invite indefiniteness and eligibility challenges, especially given the AT&T pleading maps these onto 5G UDM/UDR/AMF/SMF functions (per the previously generated litigation summary). Those are independent vulnerability tracks.

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7. Explicit uncertainties and qualifications

1. Prior-art qualification dates. Three items in the "Citations" block have publication dates after the ’066 filing date (2008‑09‑25) and therefore only qualify as prior art if their earlier applications support the relied-upon disclosure:

• US 2009/0227230 A1 (Ghost Telecom "virtual wireless network") — pub. 2009‑09‑10, but priority 2006‑03‑16.
• US 2010/0048197 A1 (Roamware "multiple MSISDN with a single IMSI") — pub. 2010‑02‑25, priority 2003‑02‑18.
• US 2010/0048208 A9 (RIM "data-capable network prioritization") — pub. 2010‑02‑25, priority 2003‑11‑12.
  Any IPR or invalidity contention relying on these must run a § 102(e)/(a)(2) priority analysis against the parent filings. I have not verified those priority chains.

1. I did not retrieve full claim sets and enabling disclosures for every reference. My mapping of Jiang to the "dual-active MDN" limitation rests on specification text ([0263]–[0266], [0270]–[0280]) and on claim 69/81 of the continuation US 2008/0293408 A1, not on a verbatim element-by-element chart against issued claims. That is sufficient for an obviousness rationale but should be verified against certified copies.
2. US 2005/0075106 A1 and US 2006/0142011 A1 — I confirmed titles/identifiers from the ’066 face and the returned listing, but did not retrieve their full specification text in this session; my reliance on them is secondary.
3. Common-ownership nuance. Lemko '267 is the applicant's own earlier application. Under the pre‑AIA regime applicable to a 2008 filing, common ownership can be relevant to § 103(c) disqualification of certain § 102(e)/(f)/(g) art — but Jiang/Roamware, Ghost Telecom, and Starhome are third-party art and are unaffected. The Jiang + Lemko combination itself remains available because Lemko '267 was cited as prior art on the ’066 face.
4. No liability or validity conclusion is expressed or implied; this is a technical invalidity-risk assessment, and the patent carries a statutory presumption of validity that must be overcome by clear and convincing evidence.

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Bottom line

The ’066 claims are vulnerable under § 103 on a two-reference combination that is unusually clean:

• Primary: US 2005/0070278 A1 (Jiang / Roamware MIMM) — discloses multiple IMSI + multiple MSISDN on one SIM, using the IMSI of the country the user is currently in, with both numbers simultaneously active as local numbers, and a signaling-gateway database holding paired IMSI/MDN plus roaming (active-location) information.
• Secondary: US 2007/0232267 A1 (Pan / Lemko) — discloses the HLR, VLR, and CLR modules in an AAA module of a distributed mobile architecture server, with multiple DMA servers linked by an IP network.

The motivation is supplied by the ’066's own admitted Background (expensive international roaming), by Jiang's explicit statement of the same objective, and by the plain engineering logic of hosting a multi-IMSI subscriber register in an existing DMA AAA node. Dependents 8–11 and 18–21 are additionally and more directly met by WO 2007/102003 A1 (Ghost Telecom) and US 2007/0213075 A1 (Roamware), which disclose MCC/MNC digit structure, multiple IMSIs on a single SIM, and automatic IMSI selection based on current location.

The principal hurdle to any invalidity challenge is procedural rather than substantive: three of the cited references post-date the filing and require a priority/§ 102(e) showing, and the "MILR module" label invites a claim-construction fight. Neither difficulty appears fatal to a well-constructed obviousness case.