US 6418324

I'll search for authoritative information on US 6,418,324 and any 2026 CAFC activity.

Let me check for any 2026 litigation activity specifically involving this patent.

Let me retrieve the actual claim text and abstract for accuracy.

Scope and method (what I actually searched)

I ran web searches targeting the exact string 6418324 / 6,418,324 against USPTO-derived sources (patents.google.com, uspto.report, FreePatentsOnline, Justia, USPTO assignment/PTAB-hosted documents), plus searches aimed at 2026 CAFC activity. I did not query PACER or the CAFC's own docket system directly, so my "no 2026 CAFC activity" conclusion rests on web search, not a docket retrieval. I also filtered out results for other identifiers that share the digits (e.g., JP 6418324 B2, a Murata multi-pole connector patent, and US 6,412,025, a PC auto-configuration patent) — those are unrelated and are expressly not reported below.

Bibliographic data — US 6,418,324 B1

Assignment chain (per Google Patents reassignment entries): Padcom Inc. (1998) → secured by Liberty Partners Lenders L.L.C. (2001) → Padcom Holdings, Inc. (2006) → NetMotion Wireless Holdings, Inc. (2013, change of name) → Mobile Sonic Intermediate, Inc. (2022, merger) → Mobile Sonic, Inc. (2022, merger).

Family members of record: WO 1999/014958 A1, EP 1042931 B1, CA 2303987 C, JP 2001-517043 A, AU 94738/98 A, AT 524035 T1. Continuation/divisional descendants include US 6,198,920, US 6,826,405, US 7,602,782, US 2005/0002419 A1, US 2004/0264402 A9.

Abstract

The abstract of record (as reproduced on FreePatentsOnline's page for 6418324) is a two-part abstract:

"An apparatus and method is provided for transparent communication between a remote or mobile device and a fixed communication host network. The apparatus and method may include a remote network controller that logically resides between the host network and the existing infrastructure(s) that are used to provide communications network contact with one or more remote devices… A router may be provided which selects a communications network in accordance with user configured parameters. The router communicates over a plurality of incompatible networks and is capable of using a variety of different protocols. Switching between the plurality of incompatible networks is transparent to the remote device and host communication network."

Caveat: the first sentence block is reproduced verbatim in the abstracts of the sibling Padcom cases (e.g., US 6,198,920), so it is boilerplate shared across the family; the "A router may be provided…" block is the portion appearing on the '324's own FPO record.

Plain-language overview of the claims

Confidence note: the Google Patents full text supplied to me contains the specification and the "Definitions" paragraphs but not the verbatim claim set, and I was unable to retrieve the full printed claim text from an authoritative source before my tool budget ran out. What follows distinguishes (a) claim language I could verify from litigation/citation excerpts from (b) claim families I am inferring from the specification's own statement of the invention.

Verified claim-content points

• The patent has a large claim set — at least 67 claims. The D. Del. opinion in Padcom, Inc. v. NetMotion Wireless, Inc. refers to "Claims 10, 49, 60 and 67 of the '324 patent," and a uspto.report reproduction of the '324 claim set shows claim numbers running through at least claim 65.
• Claims 10, 49, 60 and 67 require "at least two of the plurality of parallel wireless [networks/communication links]" to be autonomous and dissimilar and available for data transmission. The D. Del. opinion also notes that "plurality of parallel dissimilar networks" is a claim term carried across the '324/'920 family.
• Claim 45 is a computer-readable-medium claim ("A computer readable medium storing a program…"), and claim 59 is a second, independent computer-readable-medium claim directed to "dynamically routing data in a system comprising a first device and a plurality of remote devices," requiring contemporaneous monitoring of the parallel dissimilar wireless links, transmitting over a first available link, switching to a second available link, and transmitting/receiving over the second — "wherein the transmission between the first device and the remote device occurs while switching from the first communications link to the second communications link."
• Dependent claim language reproduced in that excerpt further recites: switching "immediately after transporting a first data packet and before transporting a subsequent consecutive data packet"; interfacing protocolized data into the plurality of parallel dissimilar networks "using different protocols"; switched networks; dedicated networks; digital and/or analog networks; packet-based wireless networks; digital data; and digital voice.

Independent-claim families (inferred from the specification's own summary)

The specification's "Definitions"/summary paragraphs describe the invention in the terms the independent claims use, and they fall into three families:

1. Transparent-conduit apparatus claim(s). An apparatus for transporting data between a remote device and a host network over a wireless link, comprising a mobile data controller (co-located with the remote device) that converts data between the remote device's format and the wireless-link format; a network interface means (the "remote network controller") that converts data between the wireless-link format and a network-interface format and then between the network-interface format and the host-network format; and means for transporting the data over the wireless link — with the wireless-link format and the host-network format being incompatible. The network interface means "logically resides on the host communication network and performs the functions of a network communication controller," making the remote device indistinguishable from a locally attached device.
2. Transparent-conduit method claim(s). The parallel method: connect remote device ↔ mobile data controller ↔ wireless link ↔ network interface device ↔ host network; convert at the mobile data controller; transport over the wireless link; convert at the network interface device; further convert to the host network format; forward into the host network. The transportation step is further recited as: determine wireless-link selection criteria → dynamically select a link from a plurality of incompatible wireless links → switch to the selected link, and then continuously repeat (select next link, decide whether to switch, switch if indicated).
3. Multi-network dynamic-routing claim(s) (the "router" aspect, FIGS. 29–37). An apparatus for transporting data over a plurality of incompatible networks between a first and second device, comprising: a system for determining network selection criteria (using two classes of parameters); a selection system for dynamically selecting a network per those criteria; a switching system for switching to the selected network; and a monitoring system for monitoring network availability — with transport transparent to both endpoint devices and to the end user, switching occurring between consecutive data packets, and re-selection occurring when the current network becomes unavailable. Protocols recited include Internet Protocol (IP) and a transparent protocol.

Bottom line in one sentence: the '324 claims a system and method that hide an assortment of incompatible wireless (and wired) links behind a pair of protocol-converting controllers, so that applications on the mobile device and the host LAN neither know nor care which radio network is carrying their bytes, and the link can be swapped mid-session on a packet-by-packet basis according to user-configured preference metrics.

CAFC 2026 dockets — result of the search

I found no 2026 Federal Circuit activity involving US 6,418,324. My searches for the patent number in combination with CAFC/2026 appeal terms returned only unrelated 2026 Federal Circuit decisions (e.g., AudienceScience v. Google, Constellation Designs v. LG Electronics, Ceiva v. Amazon, Slingshot v. Canon, etc.), none of which involves this patent or its assignees. Given that the patent is recorded as expired as of 2015-06-01, a 2026 appeal directed to the '324 itself would be unusual; if there is live 2026 appellate activity, it would more plausibly involve a later-issued family member (e.g., US 9,590,996 or US 9,894,514 listed on the Google Patents family timeline). I cannot rule that out on the evidence I gathered — please treat this as inconclusive rather than affirmative negative unless confirmed against a live PACER/CAFC docket query.

Historical litigation context (verified via search)

Although there is no 2026 appeal, the patent has a substantial enforcement history:

• Padcom, Inc. v. NetMotion Wireless, Inc. and Database Solutions, Inc., D. Del., C.A. 03-983 (filed 2003-10-27), asserting US 6,418,324 and US 6,198,920. Padcom's press release of that date describes the '324 as "entitled 'Apparatus and Method for Transparent Wireless Communication Between a Remote Device and Host System'… duly issued on July 9, 2002."
• Jury verdict, 2006-03-28, in D. Del.: the '324 and the '405 continuation were held valid and infringed by NetMotion's Mobility software. Verdict list at FPO's 7602782 page: Jury Verdict (DI 486), Mar. 28, 2006; followed by Stipulated Entry of Final Judgment in favor of Padcom Inc. and against NetMotion Wireless Inc.—Case Closed (DI 512), Jul. 12, 2006.
• Markman/claim construction (D. Del., Memorandum Order DI 454, Feb. 22, 2006) construed disputed terms including "dissimilar networks," followed by a motion for clarification (DI 467, Mar. 8, 2006). NetMotion's § 102 summary-judgment motions against the '324, '920 and '405 were denied (DI 453, Feb. 22, 2006).
• Padcom filed a DJ action on 2005-12-28 against NetMotion over a NetMotion-issued patent (invalidity/unenforceability/non-infringement), filed in the same district.

Key sources: https://patents.google.com/patent/US6418324/en ; https://FreePatentsOnline.com/6418324.html ; https://uspto.report/patent/grant/6418324 ; https://www.cetient.com/case/padcom-inc-v-netmotion-wireless-inc-[2500223](/patent/2500223) ; https://www.lightreading.com/business-management/padcom-sues-netmotion ; https://www.freepatentsonline.com/7602782.html .

Explicit uncertainties

1. I could not obtain the verbatim text of independent claim 1 of the '324 from an authoritative source in this session; the independent-claim descriptions above are drawn from the specification's own statement of the invention and from verified excerpts of claims 45, 48–65, 10, 49, 60 and 67.
2. The exact total claim count (≥67) is inferred rather than read off the printed patent.
3. The 2026 CAFC negative is based on targeted web search, not a PACER/CAFC docket query.
4. No auto-correction was applied to any identifier: 6418324, 08/932,532, 08/456,860, 5,717,737, 6,198,920, 6,826,405, 7,602,782 are reported exactly as they appear in the sources.

I'll research litigation involving US 6,418,324 across patent litigation databases and news sources.

Found the core dispute. Let me dig into case numbers, the DSI action, the appeal, and any other defendants.

Now let me check the Federal Circuit appeal and whether the '324 patent was asserted against any other parties.

Litigation involving U.S. Patent No. 6,418,324 ("the '324 patent")

All litigation I could confirm for the '324 patent is Padcom, Inc. v. NetMotion Wireless, Inc. and the related parallel/declaratory actions it spawned. The '324 patent was never (to my knowledge, based on the sources below) asserted in any other infringement suit. Importantly, the '324 patent was litigated together with two sibling patents — U.S. 6,198,920 ("the '920 patent") and U.S. 6,826,405 ("the '405 patent") — all continuations of U.S. 5,717,737 and all claiming priority to the September 17, 1997 filing date of the '324 application.

1. Main infringement action (the operative case)

Procedural history and outcome (grounded in the opinions):

• May 24, 2004 — D. Del. denied NetMotion's Rule 12(b)(2)/(3) motion to dismiss for lack of personal jurisdiction and improper venue, and denied DSI's § 1404(a) transfer motion. The court found NetMotion knowingly conducted business with Delaware residents (targeted telemarketing, mailings to Delaware police/fire/health-care entities, nationwide trial downloads via an HP iPAQ promotion). 2004 WL 1192641; 2004 U.S. Dist. LEXIS 9658.
• Sept.–Oct. 2005 — NetMotion moved for summary judgment of invalidity under 35 U.S.C. § 102 (Project Octopus Thesis, Carnegie Mellon 1994; BARWAN/"The Case For Wireless Overlay Networks," 1996) and § 112.
• February 22, 2006 — Judge Robinson denied NetMotion's § 102 summary-judgment motion. 418 F. Supp. 2d 589 (D. Del. 2006). Claims at issue narrowed to claims 10, 49, 58, 60, 67 of the '324 patent (plus claims of the '920 and '405 patents).
• March 28, 2006 — Jury verdict (D.I. 486) finding the patents valid and infringed by NetMotion's Mobility software.
• July 12, 2006 — Stipulated entry of final judgment in favor of Padcom and against NetMotion (D.I. 512), the docket entry being marked "Case Closed."
• NetMotion publicly stated after the verdict that it disagreed and would pursue post-trial motions and an appeal; however, the dispute was resolved by the 2006 merger of NetMotion and Padcom, with the combined company (NetMotion Wireless, based in Seattle, CEO Bob Hunsberger, Chairman Gordon Smith) continuing under the NetMotion name. Padcom had also sought a permanent injunction (opening brief filed Apr. 26, 2006).

2. NetMotion/DSI declaratory judgment action (N.D. Cal.)

3. NetMotion's tortious-interference action (W.D. Wash.)

4. Padcom's December 2005 declaratory judgment action (D. Del.)

Note on this case: this DJ action did not involve the '324 patent as an asserted patent — the '324 was Padcom's own patent asserted in 03-983. I include it because it is part of the same "case family" docket and is reported on the '324 patent's family litigation record.

5. Federal Circuit appeal

I was unable to confirm a Federal Circuit docket for the Delaware judgment. NetMotion announced an intent to appeal, and post-trial motion practice occurred (JMOL requests at the close of evidence, Rule 26 protective-order motion, permanent-injunction briefing), but the July 12, 2006 stipulated final judgment and the subsequent Padcom/NetMotion merger appear to have mooted any appeal. If an appeal was docketed and dismissed, I did not find it.

6. Additional flag

The Google Patents record for US 6,418,324 carries a "Family has litigation / First worldwide family litigation filed" link to the Darts-ip global patent litigation dataset (family=25462463). I could not open that dataset entry, so I cannot confirm whether it identifies any litigation beyond the D. Del./N.D. Cal./W.D. Wash. matters above.

Summary table

Bottom line: the '324 patent was enforced in exactly one infringement action — Padcom, Inc. v. NetMotion Wireless, Inc. and Database Solutions, Inc., Civ. No. 03-983-SLR (D. Del.) — which Padcom won at trial in March 2006 and which terminated in a stipulated final judgment in July 2006, before the parties merged later that year.

Caveats on sourcing: these details come from the D. Del. opinions (418 F. Supp. 2d 589; 2004 WL 1192641), the Delaware court's opinion page, the Federal Circuit-adjacent document listings (2005/2006 WL citations), Padcom's Oct. 27, 2003 and Dec. 28, 2005 press releases (Light Reading), Law360 (Mar. 31, 2006), NGB's April 6, 2006 report, and contemporaneous news coverage of the Padcom/NetMotion merger. I did not directly retrieve a Unified Patents litigation-portal or PACER docket sheet for these cases, and I could not confirm the docket number for the December 2005 DJ action or any CAFC appeal number.

I'll research this. The structured block says ODP shows no AIA trials, but I should verify with web search for older/unindexed proceedings.

Let me dig deeper for any IPR/CBM/reexam activity tied to this patent or the Padcom/NetMotion family.

No AIA trial hits yet. Let me check PTAB E2E-style databases and litigation history more directly.

Proceedings overview

Total AIA trial proceedings on file for US 6,418,324: zero. The structured "PTAB proceedings on file" block states the USPTO ODP API returns no AIA trial proceedings, and my targeted web searches — by patent number, by party (Padcom / Padcom Holdings / NetMotion Wireless / Mobile Sonic), and by proceeding-number prefix (IPR2015–IPR2018, CBM) — surfaced no IPR, PGR, or CBM petition, institution decision, or Final Written Decision ever filed against the '324 patent. Status breakdown: 0 active / 0 claims invalidated by PTAB / 0 claims sustained by PTAB / 0 settled / 0 institution denied. Because the '324 patent is pre‑AIA (filed 1997‑09‑17, priority 1995‑06‑01), PGR was never available; CBM was never applicable (this is a wireless data‑transport patent, not a financial‑services method, and the CBM regime sunset on 2020‑09‑16). So IPR was the only realistic AIA route, and it was never used.

Bottom line for a defendant: there is no PTAB win to lean on — but there is also no live patent. The '324 patent's anticipated expiration was 2015‑06‑01 (Google Patents legal status: "Expired – Lifetime"), and the six‑year damages lookback of 35 U.S.C. § 286 has run. The only meaningful validity event on this patent is a 2006 Delaware jury verdict holding the '324 patent valid and infringed by NetMotion Wireless. So this is not a "hardened by surviving IPRs" patent — it is an aged, expired patent that carries only historical weight. If a demand letter today cites the '324 patent for ongoing conduct, the patent cannot be infringed because it has expired; if it reaches back to pre‑2015 conduct, the six‑year § 286 window has almost certainly closed.

Per the instructions, I report no PTAB proceedings on file. Below, instead of fabricated proceeding entries, I document what was actually checked, the one non-PTAB validity contest that matters, and what it means defensively.

No AIA trial proceedings located — verification trail

• Source of record: structured ODP block in this prompt — zero AIA trial proceedings as of most recent ingest.
• Independent web checks (all negative): searches for "6418324" IPR, US 6418324 IPR Padcom, "6418324" IPR2015…IPR2018 OR CBM2015 petition, and Padcom NetMotion "inter partes review" 6418324 / 6198920 / 7602782. No petition, no PTAB docket, no FWD.
• Corroborating signal: the Google Patents '324 page flags "Family has litigation" (with a Darts‑IP family link) and links PTAB/litigation metadata, but surfaces no AIA trial link and no reexamination entry. Third‑party patent pages (FreePatentsOnline, Justia) likewise show no post‑grant contest.
• Not verified to a certainty: I did not personally pull the PTAB E2E docket or the full Post‑Grant/Reexam records in this session; I could not confirm or exclude an ex parte reexamination, which is not an AIA trial and would not appear in the ODP AIA‑trial block anyway. Say so if it matters — see next steps.
• Consequence: no 35 U.S.C. § 315(e)(2) estoppel exists against anyone. Every prior‑art ground remains available in district court.

Litigation that actually adjudicated the '324 patent (non‑PTAB, but the controlling validity event)

D. Del. C.A. No. 03‑983‑SLR — Padcom, Inc. v. NetMotion Wireless, Inc. & Database Solutions, Inc.

• Type: District court patent infringement (not an AIA trial) — included only because it is the sole validity ruling of record on this patent.
• Filed: 2003‑10‑26 (asserting US 6,418,324 and US 6,198,920; US 6,826,405 added later). NetMotion/DSI filed a mirror DJ action in N.D. Cal. on 2003‑11‑07, stayed in favor of Delaware. Jurisdictional motion decided 2004‑05‑24.
• Status: Resolved. Jury verdict 2006‑03‑28 finding the '324 and '405 patents valid and infringed ("Mobility" software); stipulated final judgment in favor of Padcom 2006‑07‑12 — case closed. Source docket items (DI 485–486, DI 512) are inventoried in the record reproduced at the related '782 patent page: https://www.freepatentsonline.com/[7602782](/patent/7602782).html; the jurisdictional opinion is at https://g.casetext.com/case/padcom-inc-v-netmotion-wireless; contemporaneous verdict report: https://www.ngb.co.jp/resource/news/2236/.
• Judge panel: Judge Sue L. Robinson (D. Del.); jury. No APJ panel — there is none, because there was no PTAB case.
• Petition grounds: n/a (no petition). In the district court, NetMotion contested validity, and Padcom filed a separate DJ action on 2005‑12‑28 challenging a NetMotion‑assigned patent as invalid, unenforceable and not infringed: https://www.lightreading.com/business-management/padcom-files-patent-suit.
• Institution decision: n/a.
• Final Written Decision: n/a. The operative disposition is the jury verdict + stipulated judgment upholding the '324 patent as valid and infringed. I will not characterize claim-by-claim reasoning the jury did not articulate.
• Settlement / termination: The Delaware case ended in stipulated final judgment for Padcom (2006‑07‑12), not a PTAB settlement. The related NetMotion‑patent DJ action and the parties' later licensing/merger path are outside the '324 record I verified; the corporate chain that followed (Padcom → Padcom Holdings → NetMotion Wireless Holdings → Mobile Sonic) is documented in the ODP assignment history.
• Appeal: I found no Federal Circuit appeal of the '324 validity judgment in the sources reviewed. If one exists, it is not surfaced here — treat as unverified, not as "none."
• Defensive value: This verdict is the reason the '324 is not a soft target on paper — a jury already rejected a validity challenge and found infringement. But it is a 2006 verdict on a patent whose term expired 2015‑06‑01. It is a historical shield for the patent owner, not a live weapon for an asserter.

Strategic summary

Canceled vs. sustained vs. untested. Because no AIA trial ever reached this patent, no claims of US 6,418,324 have been canceled, narrowed, or amended at the PTAB. Every claim stands as issued (72‑claim family lineage; the '324 issued 2002‑07‑09). But "intact" here means "intact and expired," not "intact and enforceable." The patent's anticipated expiration was 2015‑06‑01, and its legal status is recorded as Expired – Lifetime. There are no "surviving claims" in any practically assertable sense: there is no prospective infringement to enjoin and no post‑2015 damages to recover. Contrast with the family's other members — e.g., US 6,826,405 (continuation of the '324 application, asserted in the same Delaware case) — which were separately litigated; those are distinct patents with distinct files and must be analyzed on their own records.

Estoppel landscape. There is no § 315(e)(2) estoppel on the '324 patent at all, because no IPR/PGR was instituted. That cuts both ways. Favorably for a defendant: every prior‑art ground remains available in district court — nothing is barred by having been "raised or reasonably could have been raised" at the PTAB. Unfavorably: you also have no PTAB record to leverage, and if you do end up in court on pre‑expiration conduct, you face the 2006 jury determination of validity plus whatever weight the court gives it. Note the practical timing bar is stronger than any estoppel: under 35 U.S.C. § 286, damages reach back only six years from filing, so any suit filed today against pre‑2015 conduct is almost certainly time‑barred.

Pattern signals. No serial petitioner — there is no petitioner at all. No PTAB appeal history, because there was no PTAB trial. I found no evidence of a defensive aggregator (Unified Patents, RPX, etc.) in this patent's chain, which is unsurprising: the '324 was asserted by a practicing operating company (Padcom) against a competitor (NetMotion) during 2003–2006, not by an NPE sweeping a portfolio. The "patent troll" framing does not fit this patent's history. The real signal is the opposite of the prompt's hypothetical: the absence of PTAB activity is explained by expiration and by the patent's origin as a competitor‑v‑competitor assertion, not by the patent being a hardened, aggressively‑asserted NPE asset.

Recommended next steps

1. No PTAB activity exists — say so plainly, and do not build a defense around a nonexistent FWD. There is no institution decision, no Final Written Decision, and no CAFC appeal to cite. Any analysis that quotes a "'324 FWD" is fabricated.
2. Check the expiration and the § 286 window first. The patent's anticipated expiration is 2015‑06‑01; verify current status in Patent Public Search (https://ppubs.uspto.gov/pubwebapp/) and the Patent Center assignment history (https://patentcenter.uspto.gov/). If a demand letter asserts the '324 against ongoing conduct, the expiry is the complete answer; if it reaches back, run the six‑year lookback.
3. Pull the litigation record rather than the PTAB record. The controlling validity document is the D. Del. jury verdict (2006‑03‑28) and stipulated final judgment (2006‑07‑12) in C.A. No. 03‑983‑SLR. Retrieve via CourtListener / RECAP (https://www.courtlistener.com/?q=Padcom%20NetMotion) or PACER for the District of Delaware. Confirm whether any appeal was taken to the Federal Circuit — I could not verify one.
4. Sweep for a reexamination (not an AIA trial). Broadly, reexam requests surged as IPR access tightened; for a 1990s wireless patent, an ex parte reexamination is the more likely (if any) post‑grant contest. Check the Reexam Certified Search at https://www.uspto.gov/patents/search and the file wrapper via Patent Center. I could not confirm or exclude one — state it as unverified rather than "none."
5. If you are the target and a demand letter exists, the checklist is: (a) expired 2015‑06‑01 → no ongoing infringement; (b) § 286 lookback likely closed → no damages; (c) no PTAB estoppel either way; (d) the only validity ruling of record is a 2006 jury verdict upholding the patent, which is the patent owner's best talking point and which you would be attacking in district court (not the PTAB).

Caveat on sourcing: the "no proceedings" conclusion rests on the authoritative ODP block plus negative targeted web searches. Negative search results are not proof of absence; if you need a litigation‑grade negative, confirm directly in PTAB E2E (https://ptab.uspto.gov/) and PTAB Decisions (https://www.uspto.gov/patents/ptab/decisions) before relying on it.

I'll pull what I can from public records before assembling this. Let me run several searches in parallel.

Good context. Now let me try to pin down the recorded-assignment details (reel/frame, correspondents) and the litigation/assertion history.

I could retrieve the substantive ownership events and the litigation record, but not the reel/frame numbers or correspondent-of-record fields — those live behind the Assignment Center's interactive search and were not exposed in any indexed source I could reach. I'm flagging that explicitly rather than guessing, per your no-fabrication constraint.

Inventors

Pattern check — no anomaly. All three stayed associated with the invention long enough to be deposed at the 2006 trial (8–10 years post-priority). This is the opposite of the "all inventors bolt within 12 months" precursor to a fire-sale. The employer attribution rests on the recorded inventor→company assignment; Padcom's existence and product line are independently documented (below).

Source: Google Patents US6418324 legal events; FPO US7602782 file listing (trial exhibit list for the D. Del. case).

Original assignee

Padcom, Inc. (recorded as "PADCOM INCORPORATED" in the 1998 assignment), Bethlehem, Pennsylvania.

• Product embodied in the claims: Yes. Padcom shipped TotalRoam® mobile-VPN software, including TotalRoam Mobile Virtual Network (MVN), plus the 6100 and 8100 Remote Access Routers. Padcom's own litigation press release describes the asserted patents as covering "TotalRoam® software solutions … which enable roaming across multiple active dissimilar networks" — i.e., the claims are directed at a product Padcom actually sold. (Light Reading, 2005-12-28; product literature cited in the file wrapper of US 8,120,473.)
• Primary line of business: Mobile VPN / connection-persistence middleware for public safety and field-service fleets. Largest named customer: Cox Communications.
• Current status: Acquired — no longer independent. Padcom and rival NetMotion Wireless announced an all-stock merger on 2006-06-14/15, operating under the NetMotion name, and the merger terminated the pending patent litigation. Padcom's corporate shell continued as Padcom Holdings, Inc., which was renamed NetMotion Wireless Holdings, Inc. by 2013-04-03.

Sources: eWeek 2006-06-15, Dark Reading 2006-06-14, NYT DealBook 2006-06-15.

Assignment timeline

Reel/frame and correspondent-of-record: not retrievable. Every recordation below is documented as a legal event (Google Patents legal events, which mirror the USPTO assignment record's date / conveyance / assignor / assignee fields). The reel/frame identifier and the filing attorney or firm ("correspondent") per recordation are not published in any indexed source I could access; Assignment Center requires an interactive per-recordation lookup. I have therefore left both fields as not retrieved rather than inferring them. Execution dates are likewise not exposed — the dates below are recordation dates.

1. Recorded 1998-01-21 — Reel/frame: not retrieved

   • Conveyance: Assignment of assignors' interest
   • Assignor: Whitmore, David L.; Doviak, William; Houvig, Flex (all three named)
   • Assignee: Padcom Incorporated
   • Correspondent: not retrieved
   • Context: capture of founders'/employees' invention rights by the operating company at formation of the portfolio — the only non-financing, non-reorg transfer in the chain.

2. Recorded 2001-07-16 — Reel/frame: not retrieved

   • Conveyance: Security Agreement
   • Assignor: Padcom, Inc.
   • Assignee: Liberty Partners Lenders L.L.C.
   • Correspondent: not retrieved
   • Context: securitization — venture/second-lien debt collateralized by the patent portfolio. No title transfer.

3. Recorded 2006-09-06 — Reel/frame: not retrieved

   • Conveyance: Assignment (merger implementation)
   • Assignor: Padcom Inc.
   • Assignee: Padcom Holdings, Inc.
   • Correspondent: not retrieved
   • Context: internal reorg consummating the June 2006 Padcom/NetMotion all-stock merger; operating business folded into NetMotion Wireless.

4. Recorded 2012-08-31 — Reel/frame: not retrieved

   • Conveyance: Release by Secured Party
   • Assignor: Liberty Capital Partners, Inc.; Liberty Partners Lenders L.L.C.
   • Assignee: Padcom, Inc.
   • Correspondent: not retrieved
   • Context: lien release — 2001 Liberty financing discharged (11-year lien life).

5. Recorded 2012-09-14 — Reel/frame: not retrieved

   • Conveyance: Patent Security Agreement
   • Assignor: NetMotion Wireless Holdings, Inc.; NetMotion Wireless, Inc.
   • Assignee: Wells Fargo Bank, National Association
   • Correspondent: not retrieved
   • Context: securitization — refinancing; new blanket lien on the group's patents.

6. Recorded 2013-04-03 — Reel/frame: not retrieved

   • Conveyance: Change of Name (not an assignment)
   • Assignor: Padcom Holdings, Inc.
   • Assignee: NetMotion Wireless Holdings, Inc.
   • Correspondent: not retrieved
   • Context: change of name only — the entity that held record title since 2006 renamed. No change in beneficial ownership.

7. Recorded 2014-07-23 — Reel/frame: not retrieved

   • Conveyance: Patent Security Agreement (Second Lien)
   • Assignor: Lumension Security, Inc.; NetMotion Wireless Holdings, Inc.; NetMotion Wireless, Inc.
   • Assignee: Consortium Finance, LLC
   • Correspondent: not retrieved
   • Context: securitization — second-lien financing. Note the co-grantor Lumension Security, Inc., indicating the NetMotion patent group was cross-collateralized with another software company under the same lender; that does not move title.

8. Recorded 2016-10-20 — Reel/frame: not retrieved — Conveyance: Release of Security Interests; Assignor: Wells Fargo Bank, N.A.; Assignee: NetMotion Wireless Holdings, Inc.; NetMotion Wireless, Inc. Context: lien discharge ahead of recapitalization.

9. Recorded 2016-10-25 — Reel/frame: not retrieved — Conveyance: Release by Secured Party; Assignor: Consortium Finance, LLC; Assignees: NetMotion Wireless, Inc.; Lumension Security, Inc.; NetMotion Wireless Holdings, Inc. Context: second-lien discharge.

10. Recorded 2016-10-27 — Reel/frame: not retrieved — Conveyance: Release by Secured Party; Assignor: Wells Fargo Bank, N.A.; Assignees: NetMotion Wireless, Inc.; NetMotion Wireless Holdings, Inc. Context: duplicative/confirmatory Wells Fargo discharge.

11. Recorded 2022-10-18 — Reel/frame: not retrieved — Conveyance: Merger; Assignor: NetMotion Software, Inc.; Assignee: NetMotion Wireless Holdings, Inc. Context: internal upstream merger.

12. Recorded 2022-10-18 — Reel/frame: not retrieved — Conveyance: Merger; Assignor: NetMotion Wireless Holdings, Inc.; Assignee: Mobile Sonic Intermediate, Inc. Context: internal holding-company collapse.

13. Recorded 2022-10-18 — Reel/frame: not retrieved — Conveyance: Merger; Assignor: Mobile Sonic Intermediate, Inc.; Assignee: Mobile Sonic, Inc. Context: internal holding-company collapse; current recorded owner of title.

Corporate context that explains 11–13: Absolute Software Corporation acquired 100% of NetMotion Software, Inc. on 2021-07-01 by acquiring Mobile Sonic Inc., the holding company that owned NetMotion, pursuant to an Agreement and Plan of Merger dated 2021-05-11. The October 2022 recordations are the upstream merger housekeeping that followed. (Absolute Software Form 51-102F4 / Form 6-K, 2021-09-13.)

Two events that are not assignments and should not be counted as links in a transfer chain: the 2013-04-03 Change of Name, and all six Security Agreement / Release recordations (2001, 2012, 2014, 2016 ×3) — none of those transferred title.

Timeline diagram

timeline
    title Ownership of US 6418324
    1995 : Priority application filed
    1997 : Current application filed
    1998 : Inventors assign to Padcom
    2001 : Security agreement to Liberty Partners
    2002 : Patent issued
    2003 : Padcom sues NetMotion in Delaware
    2006 : Jury finds patent valid and infringed
         : Padcom merges into NetMotion
    2012 : Liberty lien released
         : Security agreement to Wells Fargo
    2013 : Padcom Holdings renamed NetMotion Holdings
    2014 : Second lien to Consortium Finance
    2016 : Wells Fargo and Consortium liens released
    2021 : Absolute Software acquires NetMotion
    2022 : Mergers leave Mobile Sonic as record owner
    2015 : Anticipated expiry under Google Patents

(The expiry line is placed last for layout only; Google Patents lists anticipated expiration at 2015-06-01, i.e. 20 years from the 1995-06-01 priority date, and status "Expired – Lifetime.")

NPE / troll-pattern signals

Global caveat: I was unable to run the two checks that would make several of these calls airtight — (a) per-recordation reel/frame + correspondent fields from Assignment Center, and (b) direct queries against RPX / Unified Patents asserter directories. Where that limitation drives the answer I say so rather than defaulting to "not present."

1. Shell-entity transfer — not present. Title never passed to a licensing-only vehicle. The assignees of title across the whole chain are: Padcom Incorporated, Padcom Holdings, Inc., NetMotion Wireless Holdings, Inc., Mobile Sonic Intermediate, Inc., Mobile Sonic, Inc. The last three are holding companies, but the chain terminates under Absolute Software Corporation (NASDAQ/TSX: ABST), a large publicly traded operating security-software vendor that acquired the group for its SASE/VPN product line. The only LLCs in the record — Liberty Partners Lenders L.L.C. (rec. 2001-07-16) and Consortium Finance, LLC (rec. 2014-07-23) — took security interests, not title, and both later filed releases. No "IP / Patents / Licensing / Ventures" suffix appears anywhere, and no registered-agent-service address was verifiable.

2. Known asserter in the chain — not present. No assignee matches Acacia, Marathon, IV, IPNav, Wi-LAN, Mosaid/Conversant, Vringo, Pendrell, Innovatio, MPHJ, Lumen View, Round Rock, Document Generation Corp, or a Spangenberg entity. Caveat: Consortium Finance, LLC is an unfamiliar financing name to me; I could not confirm or rule out any affiliation with an assertion vehicle, but it is a secured party of record, not an assignee, so it would not be an NPE in the chain in any event.

3. Repeat correspondent across the chain — unclear / not assessable. This is the single most valuable tell you asked for and it is the one I could not obtain. The correspondent field was not exposed in any indexed source I could reach, and I will not invent attorney or firm names. Recommended next step: query Assignment Center by patent number 6418324 and record the correspondent for each of the 13 recordations above; the 2001 Liberty lien and the 2012/2014 Wells Fargo and Consortium liens are the entries most likely to share lender-side counsel, and the 2006 and 2022 mergers should share NetMotion/Absolute-side counsel.

4. Cascading transfers — not present (weak negative). There is no chain of LLC-to-LLC hops. The two clusters that superficially look cascading are benign: (i) 2012-08-31 lien release → 2012-09-14 new lien (14 days apart) is routine refinancing; (ii) the three same-day mergers on 2022-10-18 are a single upstream collapse executed as three recorded instruments, occurring 15 months after Absolute's acquisition closed — a common post-acquisition housekeeping pattern, not an interval shortfall. No two assignees in the chain share a correspondent address, a principal, or a 24-month shell-hopping sequence.

5. Pre-litigation transfer — not present. The '324 was asserted by Padcom, Inc., its original owner, in Padcom, Inc. v. NetMotion Wireless, Inc., D. Del. No. 1:03-cv-00983, filed 2003-10-27. The nearest preceding recorded event is the 2001-07-16 security agreement — more than two years earlier — and no assignment intervened between the 1998 inventor assignment and the suit. Nothing in the chain was arranged within 6 months of filing to manufacture standing or venue.

6. Bankruptcy fire-sale — not present / not fully verified. No Chapter 7 or 11 proceeding for Padcom, NetMotion, or Mobile Sonic surfaced. The pattern of secured financings (Liberty Partners 2001; Wells Fargo 2012; a second-lien facility in 2014) is consistent with a leveraged balance sheet, but a second lien is not a bankruptcy, and all three facilities were discharged by recorded releases in 2012 and 2016. I did not run a PACER docket search, so treat this as "no evidence found" rather than "affirmatively disproven."

7. Privateering — not present; arguably the inverse. The 2006 transaction was an all-stock merger of two operating competitors, not a spin-out of patents to an assertion vehicle, and it terminated the litigation: the stipulated entry of final judgment in Padcom's favor is dated 2006-07-12, after the June 2006 merger announcement. NetMotion bought its way out of an injunction risk by merging with the plaintiff — competition resolution, not privateering.

8. Defensive aggregator — not present. The chain does not terminate at RPX, AST, LOT, Unified Patents, or OIN. It terminates at Mobile Sonic, Inc., a subsidiary of Absolute Software, an operating vendor.

Additional observation (non-signal): NetMotion's own US 7,714,705 was the subject of an inter partes reexamination request, Control No. 95/001,629, which the USPTO denied (decision mailed 2011-06-24). That is a neighboring patent in the same corporate family, not this patent, but it shows the family was a target of third-party validity challenges in the 2011 window.

Verdict

Operating-company assertion

The '324 patent was asserted by the entity that actually made the product — Padcom, Inc., the original assignee — against a direct competitor, NetMotion Wireless, Inc., in D. Del. 1:03-cv-00983 (filed 2003-10-27), where the jury returned a validity-and-infringement verdict for Padcom on 2006-03-28 and final judgment entered 2006-07-12 (D. Del. opinion index, Law360 2006-03-31). Every subsequent recorded event is a reorg, a name change, or a financing lien that was later released — the 2006-09-06 merger into Padcom Holdings, the 2013-04-03 change of name, the 2012-09-14 and 2014-07-23 security agreements, and the October 2022 upstream mergers ending at Mobile Sonic, Inc., now under Absolute Software. Nothing on this chain matches a known NPE, and no assertion of the '324 has been identified after 2006; the patent is also expired (anticipated 2015-06-01), which further forecloses a modern NPE campaign. The one unresolved item genuinely capable of moving this verdict is the correspondent-of-record field, which I could not retrieve.

Verify at: USPTO Assignment Center — search patent number 6418324; and mirror at assignment.uspto.gov. Patent text and legal events: https://patents.google.com/patent/[US6418324](/patent/US6418324)/en

I'll research the prior-art citations for US 6,418,324 directly against patent databases.

Let me drill into the actual citation lists.

The searches are returning forward citations. Let me get the patent's own front-page "References Cited" list.

Prior art for US 6,418,324 — analysis

⚠️ Method note and a hard limitation (read first)

What I was able to retrieve vs. what I could not:

My tool budget was exhausted while trying to pull the printed front page of US 6,418,324 (the examiner-cited "References Cited" list, USPTO form PTO-892 / the "U.S. Patent Documents" column). The searches I ran returned forward citations (documents that cite '324 — e.g., CN 1878212 B lists "US 6418324 B1, 2002.07.09, 全文", and EP 1605666 A1 lists "[X] US 6418324 B1 20020703 – DOVIAK WILLIAM [US]"), not the backward reference list I was asked to enumerate.

Forward citations are not prior art. A reference that cites the '324 necessarily postdates it (or is a same-day family member) and cannot anticipate it. I report these below only to exclude them.

Therefore the prior-art list below is not the printed PTO-892 list. It is reconstructed from three authoritative sources I did obtain:

1. The '324 specification's own "Background of the Invention" (present verbatim in the full text supplied to me) — which expressly discusses six items and names them by number;
2. The § 102 art actually asserted in litigation (Padcom v. NetMotion, 418 F. Supp. 2d 589 (D. Del. 2006));
3. Statutory family members relevant under § 102(e)/§ 120.

Identifiers filtered out (NOT reported as this patent): JP 6418324 B2 (Murata Mfg., 多極コネクタ / multi-pole connector, reg. 2018-10-19), US 6,412,025, and PMID 6418324 ("Vaginal discharge," 1984). None is US 6,418,324. No auto-correction applied.

1. Prior art cited on the face of the '324 specification

These six references are named in the '324's own background section — i.e., they are admitted prior art by the applicant. For each I give the citation as it literally appears, the date (flags where I could not verify), the description as the '324 characterizes it, and the § 102 exposure.

Date caveat: the '324 specification as supplied to me recites the patent numbers and subject matter but not issue/filing dates for these references. The dates below are my best reconstruction from patent-number issuance windows and are flagged as unverified. Do not rely on them without a fresh look at each reference's face.

A. U.S. Pat. No. 5,412,375 ("Wood")

• Citation: U.S. Pat. No. 5,412,375, cited in the '324 background as "the WOOD system."
• Description (per the '324): "a system for selecting one of a plurality of interfaces to a single wireless communications system in accordance with the capabilities of a subscriber unit and the capabilities of a base unit. A list of air interface capabilities of the subscriber unit and the base unit are compared by a controller to determine a compatible interface." The interfaces are AMPS, TDMA and CDMA.
• § 102 exposure: On its face this is the closest prior art to the link-selection claim family — i.e., claims requiring "dynamically selecting a wireless communications link from a plurality of incompatible wireless communications links in accordance with … selection criteria," and the multi-network claims (the 10/49/58/60/67 family identified in the prior section).
• Why it likely does not anticipate: the '324 itself disposes of it — "although the WOOD system does select from one of a plurality of interfaces … the routing decision is based on the capabilities of the endpoints rather than the preference metrics of the transporting networks," and "the endpoint devices … must be aware of the peculiarities of the wireless environment." That directly negates any claim requiring the networks to be autonomous and dissimilar and any claim requiring selection by network preference metrics. Wood is realistic § 103 art, weak § 102 art.

B. U.S. Pat. No. 5,420,574 (Erickson et al.)

• Citation: U.S. Pat. No. 5,420,574, to ERICKSON et al. (as spelled in the '324).
• Description: "a subscriber unit attached to a trunked mobile radio having a data input"; the radio "communicates both voice and data message formats over a wireless network to a base station via channels that are allocated by a trunked data controller which is connected to a host network." Channel states/comm parameters set by information type; the system "dynamically switches between incompatible message formats without the intervention of the endpoint devices."
• § 102 exposure: relevant to the transparent-conduit claim family (mobile data controller ↔ wireless link ↔ network interface converting between incompatible formats) and to any claim reciting endpoint-transparent operation.
• Why it likely does not anticipate: the '324 states that "only a single data path is provided," and that "the incompatibility of the two alternate paths arises from a difference in message formats rather than the use of independent, incompatible networks." So it cannot meet the "plurality of parallel dissimilar/autonomous networks" limitation. Again § 103-fodder.

C. U.S. patent application Ser. No. 08/456,860 (Doviak et al.) — the parent

• Citation: U.S. patent application Ser. No. 08/456,860, to DOVIAK et al., filed 1995-06-01 (this is the CIP parent of 08/932,532; granted as U.S. Pat. No. 5,717,737; the Google Patents record for '324 lists the priority claim "1995-06-01 Priority claimed from US08/456,860").
• Description: "a system in which a distant mobile or fixed terminal device transports data through a plurality of wireless network to an endpoint which may or may not implement the same network protocol as the distant device."
• § 102/§ 120 exposure: This is applicant's own earlier work by the same inventive entity, so it is not § 102(e) prior art against the '324 (same-inventor / common-ownership disqualification). Its real relevance is:
  • § 120 priority — it sets the earliest effective date, 1995-06-01, which Google Patents lists as the "Prior art date" for '324 and which governs which other references qualify as prior art;
  • Novelty of the "new matter" — the '324's distinguishing features (automatic selection among dissimilar networks per preference metrics; redundant/alternate pathways) are things the '324 says the parent did not do: "the DOVIAK et al. system … does not automatically transmit data through differing ones of a plurality of dissimilar networks in accordance with preference metrics … [and] does not automatically provide redundant or alternate pathways."

D. U.S. Pat. No. 5,537,220 (Ezumi et al.)

• Citation: U.S. Pat. No. 5,537,220 to EZUMI et al. (as spelled in the '324).
• Description: "a portable facsimile apparatus provided with a capability to communicate over a plurality of communications lines … telephone lines or a mobile communication unit," using an NCU controller that "adjust[s] the data rate, and transmitting and receiving signal levels based on which communication system it is communicating."
• § 102 exposure: relevant to claims reciting conversion between a remote-device transmission format and a wireless-link transmission format (the NCU rate/level adaptation), and to multi-line selection.
• Why it likely does not anticipate: the '324 states Ezumi "provides for the selection of only one single path to the exclusion of other, possible viable path based solely on which link is plugged into the NCU," and "does not switch communication paths within the boundaries of a communication session," which "further limit[s] its usefulness in a connectionless, packet data environment such as a TCP/IP network." This negates the packet-by-packet / mid-session switching limitations (see the claim-59-type recitation, "while switching from the first communications link to the second communications link").

E. U.S. Pat. No. 5,602,843 (Gray)

• Citation: U.S. Pat. No. 5,602,843, to GRAY.
• Description: "a PBX-based integrated telecommunications system having a wired subsystem connected to wired terminals, and a wireless system for connecting to mobile terminals," with a controller managing base stations/handsets and a separate PBX controller for wired terminals, including "a proximity sensor to detect wireless handsets such that when a handset is detected in proximity to a wired terminal, messages are forwarded to the wired terminal rather than the wireless handset."
• § 102 exposure: superficially relevant to claims reciting alternate path routing through wireless or wired links.
• Why it likely does not anticipate: the '324 states the "alternate routing technique does not address transporting data between the same two endpoints," and "GRAY provides no means to provide alternate path routing for a terminal device through either the wireless or wired handsets." Any claim requiring the same endpoint pair to remain addressable across a link change is therefore not met.

F. U.S. Pat. No. 5,452,471 (Leopold et al.)

• Citation: U.S. Pat. No. 5,452,471 to LEOPOLD et al.
• Description: a primary satellite system with the widest coverage plus "secondary and tertiary … terrestrial based, stationary systems"; the mobile unit "is programmed to utilize the communication system having the smallest area of coverage" on the designed assumption that more subordinate = higher capacity; the primary and secondary systems "operate together by using orthogonal channels to prevent interference."
• § 102 exposure: relevant to claims reciting selection based on preference metrics (Leopold effectively uses coverage size as the metric) and to the "two classes of parameters" selection system.
• Why it likely does not anticipate: the '324 states "the wireless frequencies employed must be derived from a continuous, compatible set of frequencies which prevents the device from selecting among inherently incompatible networks." Leopold therefore cannot meet the "plurality of incompatible networks" element — the core of the multi-network claim family.

G. Non-patent literature — The TCP/IP Companion (Arick)

• Citation: The TCP/IP Companion, by Martin R. Arick, Wiley-QED, pp. 18–19 (cited in the '324 background).
• Description: a layered-structure diagram of the seven OSI layers (physical → application).
• § 102 exposure: none. This is admitted background showing the OSI model; it discloses no apparatus or method for transparent multi-network transport.

2. The § 102 art actually asserted during litigation

Because the front-page list was not retrievable, the operative anticipation challenge is better sourced from the litigation. In Padcom, Inc. v. NetMotion Wireless, Inc. & Database Solutions, Inc., C.A. 03-983-SLR (D. Del.), NetMotion moved for summary judgment of invalidity under 35 U.S.C. § 102 against claims 10, 49, 58, 60 and 67 of the '324 (plus the '920 and '405). Judge Robinson denied the motion on 2006-02-22 (418 F. Supp. 2d 589). The two references pressed were:

• § 102 analysis note: both are printed publications and both predate the '324's 1997-09-17 filing, so they are § 102(b)/§ 102(a) art on their face. NetMotion failed to get summary judgment, meaning the court found a genuine issue of material fact as to whether each disclosed every limitation — most plausibly the "at least two of the plurality of parallel wireless networks … autonomous and dissimilar" requirement recited in claims 10, 49, 60 and 67. If you need the precise passages NetMotion relied on and the court's reasoning, that is in 418 F. Supp. 2d 589, which I did not re-open in this session.
• Caveat: I did not retrieve the two references' full text; my descriptions above are limited to the dates and the identity asserted by the parties. Do not treat the Octopus/BARWAN content descriptions as verified beyond that.

3. Statutory family — § 102(e)/§ 120, not "prior art" in the ordinary sense

The '324 sits inside a large continuation family. These cannot anticipate the '324 (they either share its priority or postdate it), but they matter for date-qualification and double-patenting:

The terminal disclaimer on the '405 is the concrete § 102-adjacent artefact here: it confirms the examiner treated the '405 and '324 as claiming obvious variants of the same invention, which is a strong signal that the differences among the family's claims are narrow and that the prior art that failed against '324 would also fail against its continuations.

4. Forward citations — reported only to exclude

These cite '324 and therefore cannot be prior art to it:

• CN 1878212 B — lists "US 6418324 B1, 2002.07.09, 全文" as 对比文件 (comparison document).
• EP 1605666 A1 — EPO search report marks "[X] US 6418324 B1 20020703 – DOVIAK WILLIAM [US], et al."
• WO 2005/094008 A1 — international search report family annex lists US 6198920 B1 → US 6418324 B1 (09-07-2002).
• Various US patents (e.g., US 8,346,160; US 8,335,187; US 10,110,436; US 9,774,695; US 10,110,436) list 6418324 | July 9, 2002 | Doviak et al. in their "Patent References Cited."

5. Bottom-line assessment

• On the face of the record I could reach, the '324's § 102 exposure is low: every one of the six patent references the applicant cited in its own background was distinguished by the applicant on the very limitation that carries the claims — that the networks be independent, incompatible, autonomous and dissimilar, and that switching occur within a session / between consecutive packets without endpoint awareness.
• The only genuine § 102 challenge of record came from two 1994–1996 printed publications (Project Octopus Thesis; BARWAN / "The Case For Wireless Overlay Networks"), and it failed — summary judgment denied 2006-02-22, and the '324 was held valid and infringed by the March 28, 2006 jury verdict.
• The most dangerous art is § 103, not § 102. Refs A (Wood), B (Erickson), D (Ezumi) and F (Leopold) each disclose one element of the multi-network claim family (interface selection / dynamic format switching / rate adaptation / preference-based selection). A combination of Wood + Leopold, in particular, is the natural obviousness attack on the "selection among dissimilar networks by preference metric" claims — and I could not verify whether the examiner considered them in combination, because I could not retrieve the front-page reference list or the PTO-892.

6. Explicit uncertainties (must be resolved before relying on this)

1. The printed "References Cited" list of US 6,418,324 was not retrieved. Everything in Section 1 comes from the specification's background discussion, which is a subset of what appears on the face — other examiner-cited art may exist that I did not name.
2. Publication/filing dates for refs A, B, D, E, F and G are unverified in this session; only the '324's own dates (filed 1997-09-17; issued 2002-07-09; earliest priority 1995-06-01) and the parent's filing (08/456,860, 1995-06-01) are confirmed from the supplied full text and the Google Patents timeline.
3. Descriptions of refs A–F are the applicant's characterizations, not my independent reading of those references. Section 2 describes the outcome of Padcom v. NetMotion, 418 F. Supp. 2d 589, but I did not re-open the opinion in this session.
4. Claim-by-claim § 102 mapping is tentative because the verbatim independent claims (notably claim 1) were not available; the mapping above uses the claim sets verified in the earlier section (10, 45, 49, 58, 59, 60, 67 and the three independent families).
5. No identifier was auto-corrected. 6418324, 5,412,375, 5,420,574, 5,537,220, 5,602,843, 5,452,471, 08/456,860, 5,717,737, 6,198,920, 6,826,405, 7,602,782, 9,590,996, 9,894,514 are reproduced exactly as sourced. JP 6418324 B2, US 6,412,025 and PMID 6418324 are expressly not this patent.

I'll ground this in the prior-art references identified in the patent's own specification, then test each against the claim families. Let me verify the references and check for additional § 103 art from the litigation record.

Let me verify the remaining cited references and check the litigation prior art that was actually raised against these claims.

Let me check the two references NetMotion actually asserted against these claims, and the § 102/§ 103 record in the 2006 opinion.

Obviousness Analysis — U.S. 6,418,324 under 35 U.S.C. § 103

Analyst note on scope. Per the instruction, this analysis uses the prior art identified in the "Prior Art"/Background section of the '324 as it appears on the page (the references the applicants themselves discussed), supplemented by the two references that appear in the family's own reference record and were asserted below. I continue the three claim-family convention (Family 1 = transparent-conduit apparatus; Family 2 = transparent-conduit method; Family 3 = multi-network dynamic-routing/"router") from the previously generated sections and will not re-describe them. Where I reach a conclusion I cannot ground in retrieved text, I say so.

I. Threshold issues that drive the whole § 103 analysis

A. Priority date is not uniform across the claims — this is the single most important § 103 lever

The '324 is a continuation-in-part of 08/456,860 (US 5,717,737), filed 1995-06-01, but was itself filed 1997-09-17.

• New matter first appearing in the CIP is entitled only to 1997-09-17.
• The specification's own FIG. 29–37 "Router" disclosure (the mobile router with Decision process, Network Availability process, User Configured parameters, and the Switch) is the new CIP material — it is the last-described embodiment in the document and is not part of the parent's stated subject matter (the parent is described in the Background as the "distant mobile or fixed terminal device transports data through a plurality of wireless network" system lacking automatic preference-metric routing).
• Therefore, Family 3 claims (network-selection criteria → dynamic selection → switching → monitoring, transparent to endpoints) plausibly get only the September 17, 1997 date. Under § 102(b), that makes anything published before September 17, 1996 statutory prior art against Family 3 — including the Jan. 1996 Katz & Brewer paper and the Feb. 28, 1996 BARWAN COMPCON paper.

Confidence: moderate-high on the legal principle; low-moderate on which specific claims were first supported in the parent, because I do not have the parent's disclosure or the file history in front of me. This should be resolved from the 08/456,860 specification before any § 103 position is finalized.

B. Art that is not available

US 5,717,737 / application 08/456,860 (Doviak et al.) is not § 103 art against the '324. It is the work of the same inventive entity (Doviak, Whitmore, Houvig) and, moreover, the commonly-owned-parent exclusion of pre-AIA § 103(c) applies to § 102(e)/(f)/(g) art. Its only proper role here is (i) as a priority/§ 112 written-description yardstick and (ii) as the inventors' own admission of what the art already contained. Any § 103 ground that leans on the '737 to supply the "transparent conduit" element is legally improper, and this is a trap the examiner-cited art layout invites.

Likewise, The TCP/IP Companion (Arick, Wiley-QED, pp. 18–19) is cited for OSI layering background only and supplies no claim element.

C. Level of ordinary skill (PHOSITA)

A person having ordinary skill as of mid-1995–1997 in this art would hold a B.S. in EE/CS plus 2–4 years in wireless data/mobile networking, or equivalent. That person would be familiar with: OSI layering and TCP/IP; RF link-layer protocols for point-to-point, repeater, LTR, Motorola and EDACS trunking; asynchronous serial framing; CRC/ARQ retry; and — critically — the then-current academic "wireless overlay" literature on heterogeneous networks and vertical handoff. This framing matters: it makes the overlay-network literature reasonably pertinent, not obscure.

II. The prior-art set identified in the '324's own Background section

Key structural observation: the '324's Background is, in effect, the applicants' own admission that every discrete element of the invention was known — multi-interface air-interface selection (Wood), endpoint-transparent message-format switching on trunked radio (Erickson), multiple selectable communication lines with per-line rate/level adaptation (Ezumi), transparent data-link encapsulation bridging plus standby-channel handoff plus rerouting between wired and wireless (Gray), and hierarchical preference for the "best" available system (Leopold). What the applicants assert as novel is the specific coupling: selection driven by transport-network preference metrics, across mutually incompatible autonomous networks, mid-session / between consecutive packets, with protocol conversion at both ends so that both endpoints remain unaware.

That is precisely the kind of case KSR Int'l Co. v. Teleflex Inc., 550 U.S. 398 (2007), addresses: a combination of known elements, each performing its known function, yielding a predictable result.

III. The two references the family's own record shows were asserted (and why they are the strongest § 103 art)

The FPO reference list on sibling US 7,602,782 includes:

• Katz, R.H. et al., "The Case for Wireless Overlay Networks," Proc. SPIE Multimedia and Networking Conf. (MMNC '96), San Jose, CA, Jan. 1996.
• Katz, R.H., "Adaptation and Mobility in Wireless Information Systems," IEEE Personal Communications Magazine, vol. 1, no. 1, 1995.
• Katz, R.H. et al., "The Bay Area Research Wireless Access Network (BARWAN)," Proc. IEEE COMPCON '96, Feb. 28, 1996, pp. 15–20.
• The "Project Octopus Thesis" (Carnegie Mellon, 1994) named in the D. Del. § 102 motion.
• Katz & Brewer, "The Case for Wireless Overlay Networks," ch. 23 in Mobile Computing, Kluwer (1996) — the same paper, book form.

The retrieved abstract of Katz & Brewer is, on its face, a statement of the '324's stated problem:

"…future mobile information systems must be built upon heterogeneous wireless overlay networks, extending traditional wired and internetworked processing 'islands' to hosts on the move over coverage areas ranging from in-room, in-building, campus, metropolitan, and wide-areas… we describe our approach towards a new wireless data networking architecture that integrates diverse wireless technologies into a seamless wireless (and wireline) internetwork. In addition, we describe the applications support services needed to make it possible for applications to continue to operate as mobile hosts roam across such networks."

Note the "wireless (and wireline)" integration — that is the mixed wireless/wired medium selection recited in the '324's claim family. And note that the retrieved Related Work section of the follow-on Stemm & Katz paper confirms that "The term 'Wireless Overlay Networks' was first introduced in [17]" (the MMNC '96 paper), and that the overlay work addressed "how to switch from one network interface to another in a manner that is completely transparent to the user," and that "the diversity that arises from being able to receive packets on multiple network interfaces simultaneously" was central.

Date caution (material): the Stemm & Katz, "Vertical Handoffs in Wireless Overlay Networks," ACM MONET, Spring 1998 paper is after the '324's 1997-09-17 filing and is therefore not prior art even against Family 3. Its doublecasting/zero-loss-handoff discussion must not be used. The MMNC '96 and COMPCON '96 papers are before 1997-09-17 (and are § 102(b) art if Family 3 gets the 1997 date). I was unable to retrieve the full text of the MMNC '96 paper, so I cannot confirm whether it discloses (a) switching between two different networks for the same session as opposed to roaming between cells of an overlay, or (b) protocol conversion at the fixed host boundary. This is the pivotal factual gap in the analysis and should be closed by pulling the paper.

IV. Ground-by-ground § 103 formulations

Ground 1 — Wood + Gray (+ Ezumi) → targets Families 1 and 2

Motivation to combine (KSR-compliant):

1. Same field, same problem. Wood, Gray and Ezumi all address connecting a mobile terminal to fixed network services over an RF link and all expressly address which of several links to use.
2. Reference-to-reference teaching. Gray expressly identifies the problem of the wireless medium being unstable and requires handoff "imperceptible to the user," and expressly contemplates wireless data terminals on a LAN — so Gray invites the addition of a link-selection policy such as Wood's.
3. Functional complementarity. Wood supplies the ranked-preference selection logic that Gray lacks (Gray's switching is triggered by channel degradation of active/standby channels, not by a user/operator preference metric). Wood's express teaching that interfaces may be ranked "by some operator designated preference" is the very "preference metrics" limitation.
4. Predictable result / no change in principle of operation. Combining an air-interface selector with a transparent encapsulation bridge does not change what either does; each performs its known function in its known way.

Where Ground 1 is weak — and it is weak:

• Wood's air interfaces (AMPS/TDMA/CDMA) are, on the '324's own characterization, capabilities of a single wireless communications system, not "autonomous and dissimilar" networks as required by claims 10/49/60/67. A petitioner must show that AMPS and CDMA air interfaces, or CDMA and a LAN, are "autonomous and dissimilar" under the D. Del. construction of "dissimilar networks" (DI 454, Feb. 22, 2006) — which I have not retrieved. Absent that, Ground 1 does not reach claims 10, 49, 60, 67.
• Gray's bridge is a data-link-layer encapsulation inside the wireless subsystem, not a conversion from a wireless-link format to a host-network format; Gray's own statement is that the two controllers' signaling is "identical," which cuts against the recitation of incompatible formats.
• Neither Wood nor Gray performs selection "between the transport of consecutive data packets," which is the recited switching granularity.

Assessment: Ground 1 is a credible rejection of the broadest transparent-conduit independent claim (Family 1) if and only if the claim does not require two autonomous dissimilar networks. It is probably insufficient against the claims the parties actually fought over (10, 49, 58, 60, 67).

Ground 2 — Katz & Brewer (MMNC '96 / BARWAN COMPCON '96) + Gray + Wood → targets Family 3, and is the strongest ground

Motivation to combine:

1. Explicit problem statement in the art. Katz's abstract states the purpose — making applications "continue to operate" as hosts roam across heterogeneous networks — which is the '324's stated object ("transparent data path… without either the remote device, or the wired network being aware that a wireless RF communications link is being employed"). Where the prior art states the same problem the patent states, the motivation inquiry is largely answered.
2. The combination was "obvious to try" in the KSR sense. Katz teaches the architecture but the cited materials are architectural; Gray and Wood supply the implemented selection and bridging mechanisms. KSR expressly sanctions combining a teaching that "merely describes the concept" with a reference providing the implementation details of known functions.
3. Design incentive directly stated in Gray. Gray identifies the need for switching fast enough to be imperceptible and the difficulties of coordinating controllers; that is the design incentive to adopt an overlay/handoff approach.
4. No teaching away. None of Wood, Gray, Ezumi or Leopold disparages switching networks mid-session for data; Ezumi is silent on the point, which is not a teaching away.

Assessment: Ground 2 is the most likely to succeed because it matches the claim's purpose language, and because the Katz/BARWAN materials also help surmount the "dissimilar/autonomous" limitation that defeats Wood alone. But its viability is date- and content-dependent: (i) it requires Family 3's claims to carry the 1997 date; (ii) it requires the MMNC '96 text to disclose selection/switching among autonomous networks rather than handoff among cells; (iii) it requires art for the per-packet switching granularity, which I could not confirm.

Ground 3 — Leopold + Wood + Gray → targets Families 1, 2, 3 (hierarchical preference)

Leopold supplies, expressly, (a) a hierarchy of coverage regions, (b) a mobile unit programmed to prefer the smaller-coverage/higher-capacity system, and (c) a single subscriber unit selecting among plural systems. Wood supplies capability/preference comparison and re-selection; Gray supplies transparent encapsulation, channel monitoring and a common controller.

Motivation: same problem (maximize capacity/reliability for a roaming terminal); Leopold's hierarchical preference is literally a "network selection criterion"; Gray's bridge supplies the transparency.

Why this ground is the weakest of the three:

• The '324's own Background states that Leopold's systems "operate within one frequency spectrum… using orthogonal channels," so Leopold teaches away from selecting among "inherently incompatible networks" — the applicants used Leopold to demarcate the invention, and that demarcation is an admission that can be turned into a teaching-away argument. Expect a patent owner to press this hard.
• Leopold is a satellite/cellular voice architecture with no protocol conversion to a host network format.

Assessment: useful as a secondary reference to show the general knowledge of preference-based system selection, but should not be the primary reference.

Ground 4 — Project Octopus (CMU 1994) + Gray + Wood

The "Project Octopus Thesis" was asserted below and, per the D. Del. opinion, was directed to the § 102(a) theory (invalidity). I have not retrieved the thesis, so I cannot map it limitation-by-limitation and I decline to assert what it discloses. Its significance here is procedural: it establishes that the defendant's chosen anticipation reference was a 1994 academic thesis on mobile networking, i.e., that the "wireless overlay / mobile internetworking" literature was reasonably pertinent art by the 1995–1997 window. If its content includes heterogeneous-interface selection transparent to applications, it belongs in Ground 2 alongside Katz as alternative primary art. Confidence: insufficient to opine.

Ground 5 — Administrative/secondary combinations

• Erickson + Gray: for the "switching without intervention of the endpoint devices" and channel-state-parameter-setting limitations. Erickson's gap (only a single data path; format incompatibility rather than independent networks) means Erickson should be used only as evidence of the knowledge of endpoint-transparent channel/format switching, not as a primary reference.
• Ezumi + Wood + Gray: Ezumi supplies selecting among plural communication lines and adapting data rate and signal levels to the selected line — i.e., per-link protocol/parameter adaptation at an interface device. Ezumi is more useful for the "remote data conversion means"/format conversion element of Family 1 than for the network-selection element.
• Gray + Gray: note that Gray's own FIG. 3 system with two controllers sharing load and bridged transport buses is directly pertinent to the '324's redundant remote network controllers with a subsystem synchronization process over a local network aspect (FIGS. 27–28) — including the recited sharing of routing tables and health/status ("a bus master… connected over a Gbus" to base stations "and controllers"; "the scheme allows load sharing between two controllers… Bridges link the various transport protocol buses"). This is a strong § 103 position against that dependent aspect.

V. Consolidated motivation-to-combine rationale (usable across grounds)

1. All references are in the same field of endeavor (RF data/voice communication between mobile terminals and fixed network facilities) and are therefore a priori combinable; KSR, 550 U.S. at 415.
2. The prior art states the '324's own objective. Gray: handoff "imperceptible to the user" and the PBX treating wireless devices as "ordinary station sets." Katz: applications must "continue to operate as mobile hosts roam across such networks." Leopold: the unit is "programmed to utilize" the preferred available system. Each stated objective is a motivation to complete the combination.
3. Known techniques combined to yield predictable results. Protocol conversion at a boundary device (Ezumi's NCU adaptation; Gray's encapsulation bridge) and network selection by preference metric (Wood's ranked list; Leopold's hierarchy) were each known; selecting one of several available links and converting protocols are independent, non-interfering functions. KSR's "predictable variations of known elements" and "obvious to try" rationales both apply.
4. Market/technical pressure. The then-nascent demand for seamless mobile data over heterogeneous coverage (Katz's motivation for overlays; Gray's motivation for transparent bridging) supplies the "design incentive" and "market demand" rationales recognized in KSR.
5. No criticality or unexpected result shown in the art for any specific selection metric; the claims recite metrics generically ("user configured parameters," "selection criteria using two classes of parameters"), which is the classic invitation to a "results-effective variable" / obvious-to-try finding.

VI. Where a § 103 case probably fails, and the counter-evidence

1. The validity judgment below. The D. Del. jury found the '324 valid and infringed on March 28, 2006 (DI 486), after the court denied NetMotion's § 102 summary-judgment motion (418 F. Supp. 2d 589). A jury validity verdict presumptively includes non-obviousness, and the § 103 record as tried is not in my retrieved materials. Any obviousness opinion must be reconciled with that verdict — not treated as overridden by it, but not ignored either.
2. The "autonomous and dissimilar" limitation is the crux. Claims 10, 49, 60 and 67 require "at least two of the plurality of parallel wireless [networks/links]" to be autonomous and dissimilar (per the previously generated section, quoting the D. Del. opinion's recitation of those claim numbers). Wood alone fails this; Leopold's same-spectrum systems arguably fail it; Gray's bridge arguably fails it (identical controller signaling). Only Ground 2 (Katz/BARWAN) directly attacks it, which is why Ground 2 is essential.
3. The per-packet switching limitation. Claim 59 (and the dependent language reproduced from the claim excerpt: switching "immediately after transporting a first data packet and before transporting a subsequent consecutive data packet") is the narrowest and hardest element. Ezumi is expressly cited in the '324 as not switching "within the boundaries of a communication session." I have no retrieved art that teaches per-packet granularity for this switching, and I will not invent one. This limitation, if construed to require packet-boundary switching, likely survives all four grounds on the present record.
4. The parent cannot help the petitioner (§ I.B) — but it also cannot help the patent owner as novelty-creating prior art; the owner must rely on the '324's own disclosure.
5. Means-plus-function exposure. Family 1's "means for transporting the transported data" and "network interface means" invite § 112(f) construction. If construed to require only the disclosed equivalents (host data controller + mobile data controller + RF interface modules), the art mapping shifts to structural equivalents (Gray's group controller; Ezumi's NCU), which is more favorable to the petitioner but requires a § 112(f) claim-construction position first.

VII. Bottom line

1. The patent's own Background section concedes every discrete element — multi-interface selection (Wood), endpoint-transparent format/channel switching (Erickson), multi-line selection with per-line adaptation (Ezumi), transparent data-link encapsulation bridging with standby-channel handoff, wired/wireless rerouting, and multi-controller load sharing/bridging (Gray), and hierarchy-based system preference (Leopold). On that record, the broad transparent-conduit claims (Family 1) are exposed to Wood + Gray + Ezumi, and Gray alone or with minimal supplementation is strong § 103 art against the multi-controller-with-synchronization and transparent-bridging aspects.
2. The strongest single § 103 ground is Katz & Brewer (MMNC '96 / BARWAN COMPCON '96) + Gray + Wood against the Family 3 "router" claims, because Katz states the '324's own objective (heterogeneous wireless and wireline internetworking with applications continuing to operate as hosts roam) and thereby supplies both the "plurality of incompatible/autonomous networks" element and the "transparent to the endpoints and the end user" element that defeat the other grounds. Its viability depends on Family 3 claims receiving the 1997-09-17 date (they likely do, as CIP new matter) and on the MMNC '96 text disclosing selection/switching among autonomous networks.
3. Leopold + Wood + Gray is the weakest ground because the applicants planted a teaching-away (same compatible, orthogonal frequency set) in the specification itself.
4. The per-packet / consecutive-packet switching limitation (claim 59 and its dependents) is not met by any reference in the set I could verify. A § 103 case should be built to avoid needing it, or the petitioner must find art expressly disclosing session-persistent, packet-granular link switching.
5. The claims were adjudged valid by a 2006 jury. That is a real obstacle and a secondary-consideration data point (the accused NetMotion Mobility product was commercial and the jury found infringement), and it should be addressed head-on.

Confidence and explicit gaps. Verbatim independent claim 1 of the '324 remains unretrieved (as noted in the prior section). I did not retrieve the MMNC '96 paper, the Project Octopus thesis, the 08/456,860 specification, or the D. Del. claim construction of "dissimilar networks" (DI 454). Each of those four documents is outcome-determinative for at least one of the grounds above, and none of my conclusions should be treated as final until they are obtained. Identifiers are reproduced exactly as they appear in the sources; no auto-correction was applied.