US 5742592

I'll search for authoritative information on this patent number.

Let me run a couple more targeted searches on litigation/docket activity.

US Patent 5,742,592 — Summary

Important caveat up front: I searched for USPTO records, litigation, and CAFC 2026 docket activity tied to this specific number. I found no CAFC (Federal Circuit) 2026 docket entry and no pending district-court case asserting US 5,742,592. The patent's legal status is "Expired – Lifetime," with anticipated expiration 2015-09-01, which is consistent with there being no live 2026 appeal docketed on this patent. I did not locate any authoritative litigation record for this patent, so treat litigation-related statements as "no evidence found," not as proof of non-existence. Everything below on the patent itself is grounded in the USPTO/Google Patents record and the full patent text.

Bibliographic data

Sources: Google Patents (https://patents.google.com/patent/US5742592A/en), uspto.report (https://uspto.report/patent/grant/5742592), Unified Patents portal (https://portal.unifiedpatents.com/patents/patent/US-5742592-A).

Abstract (as issued)

"The disclosed system is capable of allocating plural subchannels based on user data priority. In one embodiment, a subscriber determines the throughput it would like and fragments a data packet in that number of service data units, and requests that number of subchannel allocations from a serving base station. Upon receipt of the access request(s), including any priority indicators, the system determines from the access request(s) whether to allocate the subchannel(s) to the subscriber. Further access requests are received periodically and scheduled, and when a higher priority message is received, completion of a lower priority message is deferred and the higher priority request allocated. Thus, an improved access procedure is provided accommodating varying throughput rates with a more robust transfer because of the packet fragmentation and multiple-subchannel transfer."

Plain-language overview of the independent claims

The patent has four independent claims — 1, 7, 10, and 11 — with claims 1/7/10 written from the transmitting subscriber unit perspective and claim 11 from the network/infrastructure perspective.

Claim 1 (fragment, encode, multi-subchannel transmit with re-allocations):
A method for sending plural data packets in a wireless system. The steps: (a) fragment one data packet into multiple data units ("PDUs"); (b) encode each PDU into encoded PDUs ("E-PDUs"); (c) request several subchannels of the communications resource; (d) receive an allocation of at least one designated subchannel for a first time period; (e) receive subsequent allocations of that subchannel for subsequent time periods, such that all E-PDUs will each get assigned a time period for transmission; and (f) transmit each E-PDU on one of the designated subchannels — during the first period sending a first E-PDU on the first designated subchannel and a second E-PDU on the second designated subchannel — until all E-PDUs are sent. In plain terms: chop the packet up, code each piece, ask for bandwidth, and send the pieces out over one or more subchannels across repeatedly re-granted time windows rather than one continuous grant.
(Note a drafting tension in the claim: it recites "at least one designated subchannel" but then references "the first designated subchannel" and "the second designated subchannel," implying two or more. This ambiguity is in the granted text and is worth flagging for any claim-construction analysis.)

Claim 7 (request m, receive n ≤ m, fragment into n units):
A method where the unit requests m subchannels for a data packet, but receives an allocation of only n designated subchannels (n between 1 and m); it then fragments the packet into n data units, encodes each into n E-PDUs, and sends each E-PDU on one of the n designated subchannels until all are transmitted. Plain terms: you ask for more bandwidth than you may get, and you size your fragmentation to whatever you are actually granted. (Dependent claims add: two-stage access request with capability/priority parameters — claim 8; and asynchronous transmission of the n E-PDUs — claim 9.)

Claim 10 (apparatus mirror of claim 1):
An apparatus with a transceiver and a coupled processor programmed to perform the same steps as claim 1 — fragment, encode, request plural subchannels, receive an allocation for a first period, receive subsequent allocations for subsequent periods so all E-PDUs get a transmission slot, and transmit each E-PDU over a designated subchannel (including simultaneous first/second E-PDU transmission in the first period). Essentially the device counterpart of the claim 1 method.

Claim 11 (network-side perspective, with re-allocation after monitoring for higher priority):
A method at the infrastructure side: receive a subchannel-allocation request from a first unit; transmit an allocation of at least one subchannel to that first unit; receive a first portion of an E-PDU from it; monitor for higher-priority requests from other units; if no higher-priority request arrives, transmit a second allocation to the first unit; and then receive a second portion of that same E-PDU. Plain terms: the base station grants short, limited allocations and re-grants them, checking in between whether a higher-priority user needs the channel. (Dependent claim 12 covers the interruption scenario: receive a higher-priority request, defer the first unit's allocation, serve the second unit, then re-allocate to the first unit and receive its second E-PDU portion.)

Claim 1's dependent-claim variants (context)

Claims 2–6 narrow claim 1 to: fragmentation based on a determined desired throughput rate (cl. 2); CDMA-multiplexed subchannels (cl. 3); CDPD radio channel (cl. 4); E-PDUs as error-correction-encoded codewords (cl. 5); and TDMA-multiplexed subchannels (cl. 6).

Cited prior art on the face of the patent

US 4,745,599 (Raychaudhuri); US 5,161,194 (Ujiie); US 5,260,989 (Jennes et al.); US 5,440,545 (Buchholz et al.); US 5,555,266 (Buchholz); US 5,583,869 (Grube et al.); US 5,606,561 (Scheibel); US 5,648,967 (Schulz). The examiner-cited art is notably a mix of Motorola and non-Motorola references, several of which are packet-fragmentation or wireless-resource-allocation patents.

Uncertainty / limits of this analysis

• CAFC 2026 dockets: I found no Federal Circuit docket or opinion for US 5,742,592. Given the September 1, 2015 expiration, a 2026 appeal is unlikely, but I cannot represent this as an exhaustive negative from the searches performed.
• Assignee field discrepancies: Google Patents lists the current assignee as Google Technology Holdings LLC; the Unified Patents portal also surfaced "Motorola Solutions Inc" in its assignee display. The recorded assignment chain supports Google Technology Holdings LLC as current owner. I have not independently verified the live USPTO assignment record.
• Dates: The user-supplied current date (April 26, 2026) differs from the system fetch date shown for the source (2026-09-29). This does not affect the bibliographic data, which is fixed by the patent's own record.
• No search result for "5742592" was used that referred to a different patent number; results cited above are for US 5,742,592 / US5742592A specifically.

I'll search multiple litigation-focused sources for this specific patent number.

Let me run additional targeted searches on litigation-specific databases.

Let me try a few final targeted searches through litigation databases.

Litigation search results for US Patent 5,742,592

Bottom line: I found no known litigation involving US 5,742,592. No district court complaint, no ITC investigation, no PTAB/IPR proceeding, no Federal Circuit appeal, and no assignment/ownership dispute litigation tied to this patent number were located in any of the sources searched.

Sources searched and what they returned

Unrelated hits (explicitly excluded, per your instruction not to auto-correct or conflate numbers)

• A Dutch municipal permit publication citing case number 5742592 (Hoofddorp, Netherlands) — a local administrative matter, not a US patent case.
• A Finnish patent FI105752B citing US 5742592 as prior art in its search report — a citation, not litigation.
• PCT search report WO2001035227A3 listing US 5742592 A as a family/publication reference — a citation, not litigation.
• Various results for totally different patent numbers (e.g., the '574 patent in a fenofibrate ANDA case, the '742 patent in an Illumina IPR) — different patents, do not conflate.

Case table (as requested)

Why this is consistent with the record

• The patent is Expired – Lifetime, with an anticipated expiration of September 1, 2015 (20 years from the September 1, 1995 filing date).
• It was never, so far as the public record shows, asserted as a patent-in-suit. The large "Cited By" count (138 cited-by listings in the Google Patents record; 375 in Unified Patents) reflects forward citations by later patents, which is often mistaken for litigation activity — it is not.

Caveats (stated explicitly, per the ground rules)

1. This is a negative finding from the sources searched, not an exhaustive negative. PACER is not fully full-text searchable by patent number for older closed cases, and NPE suits from the 1998–2015 window could theoretically exist in paper-era dockets never indexed online.
2. Federal Circuit dockets are indexed by appeal number, not by patent number, so a pre-2015 appeal involving US 5,742,592 would not necessarily surface in a patent-number search. I found no such appeal.
3. I did not identify any litigation-related document, and I am not aware — with any confidence — of any case asserting this patent. I will not state that none ever existed; only that none is discoverable in the searched sources.
4. Flag on the prior section: the earlier summary noted a date discrepancy (user-supplied "current date" of April 26, 2026 vs. source fetch date 2026-09-29). The litigation conclusion is unaffected. Also, the earlier section flagged an assignee discrepancy (Motorola Solutions Inc. vs. Google Technology Holdings LLC); Unified Patents likewise surfaces both names, while the recorded assignment chain (→ Motorola Mobility → Google Technology Holdings LLC, 2015-04-02) supports Google Technology Holdings LLC as current owner.

Recommendation if you need a definitive negative: order a PACER docket search across all district courts and an ITC EDIS search, and check Lex Machina / Docket Navigator (which index by patent number back to the 1990s) for "5,742,592." Those paywalled databases are the standard tools for a conclusive litigation history, and I cannot query them directly.

I'll verify the structured "no proceedings" default against public sources before reporting.

Let me run additional targeted checks for any AIA trial, reexam, or appeal activity tied to this patent.

Two more verification passes — checking PTAB docket aggregators and the possible "'592 patent" name collision.

PTAB / AIA Trial Proceedings — US 5,742,592

Source-of-truth note: The structured "PTAB proceedings on file" block supplied in this prompt — the canonical list from the USPTO Open Data Portal — returns zero AIA trial proceedings for US 5,742,592. I treated that as the default and ran independent web verification against PTAB docket aggregators, USPTO PTAB document repositories, and law-firm PTAB trackers. Nothing in those searches contradicts the ODP result.

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Proceedings overview

Total AIA trial proceedings on US 5,742,592: zero (0) — no IPR, no PGR, no CBM, in any status (no active trials, no FWDs invalidating or sustaining claims, no settlements, no institution denials). The defensive posture this gives a defendant is not "the patent is hardened by surviving IPRs," and not "the claims are already dead" — it is the third, less common posture: the patent has never been challenged at the PTAB at all, and on its face it is expired as of 2015-09-01. Any demand letter citing this patent is asserting a patent whose enforceable life ended roughly a decade ago; the PTAB question is close to moot, and the real fight (if any) is about the § 286 six-year damages lookback, not about claim survival.

Individual proceedings

None to report. Per the operating constraints, I will not invent proceeding numbers to fill this section. For completeness, here is what I checked and what I found:

⚠️ One name-collision I could not fully resolve — do not misattribute it

A search hit from a Banner Witcoff-hosted institution decision for IPR2025-00050 contains the sentence:

"Petitioner asserts that claims 1-3 and 5 of the '592 patent would have been obvious over Walker."

This is almost certainly a different '592 patent, not US 5,742,592. The same decision defines the person of ordinary skill as having experience with "television and digital display systems, distributed multimedia communications, and networked computer systems," and the sole ground runs on a reference called Walker. US 5,742,592 is a GPRS/TDMA wireless packet-data patent whose field of art is cellular radio resource allocation — there is no coherent way a TV/display-systems obviousness ground against a Walker reference maps onto it. I was unable to retrieve the actual patent number for IPR2025-00050 (search budget exhausted), so I am not asserting it is a proceeding on this patent, and I am not asserting it is not — I am flagging it as an unresolved identifier collision. Verify the patent number in IPR2025-00050 before relying on it in any brief. If it turns out to be 5,742,592, that would be the single most important development in this patent's post-grant history and everything below would need revision.

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Strategic summary

Claim status: all 12 claims are UNTESTED at the PTAB. No claim of US 5,742,592 has ever been canceled, confirmed, or even instituted upon in an AIA trial. Claims 1, 7, 10, and 11 (the independents) and dependent claims 2–6, 8, 9, 12 stand exactly as they issued on 1998-04-21, with no Certificate of Correction or reexamination certificate identified that would alter their scope. The practical consequence is that there is no PTAB record to point a court to for either side. A defendant cannot say "claim 1 is already dead"; the patent owner cannot say "this patent survived three IPRs." The claim-construction ambiguities already flagged in the summary section — notably claim 1's internal inconsistency between "at least one designated subchannel" and the later recitation of "the first designated subchannel" and "the second designated subchannel" — remain completely unlitigated at the Board, which is a genuine defensive asset for an accused infringer: there is no adverse PTAB construction on the record.

Estoppel landscape: there is no § 315(e)(2) estoppel, because there is no petitioner. Estoppel only attaches to a party that was a petitioner (or real party in interest / privy) in an instituted IPR that reached a final written decision. With zero petitions filed, no IPR-based estoppel exists against anyone on this patent, and conversely there is no settled set of prior-art grounds that a petitioner is stuck with. Every ground that the eight examiner-cited references — US 4,745,599 (Raychaudhuri); US 5,161,194 (Ujiie); US 5,260,989 (Jennes); US 5,440,545 (Buchholz); US 5,555,266 (Buchholz); US 5,583,869 (Grube); US 5,606,561 (Scheibel); US 5,648,967 (Schulz) — could support, plus everything the examiner never saw, is fully available to a defendant under §§ 102/103, whether asserted in district court, in an IPR, or in an ex parte reexam. Nothing has been spent, burned, or foreclosed.

Pattern signals. There is no petitioner and therefore no repeat-filer pattern, no Unified Patents–style defensive-aggregator proceeding, and no patent-owner PTAB appeal history for this patent. The absence is explained by timing and economics rather than by the patent's strength: US 5,742,592 issued in 1998, expired 2015-09-01 (20 years from its 1995-09-01 filing, with no term extension in the record), and its AIA-era exposure window (IPRs available from 2012-09-16) overlapped only the last three years of its term. The patent owner's known Motorola-family litigation and ITC activity (e.g., the Motorola Mobility campaigns of 2010–2012) involved different patents — the record shows the '697, '317, '223, and '826 patents in that particular ITC/Apple dispute, not this one. An expired patent with no ongoing assertion campaign simply does not attract IPRs, because the cost/benefit rarely closes. The absence of PTAB activity here is therefore weak evidence about validity and strong evidence about enforceability timing — nobody found it worth attacking because nobody found it worth asserting.

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Recommended next steps

Framing for a defendant. This is not an IPR-strategy case; it is an enforceability-and-damages case. Sequence your work as follows:

1. Lead with the terminal date, not the prior art. Confirm on the face of the patent and via USPTO PatentCenter that the term ended 2015-09-01 with no disclaimer-free extension of the type found elsewhere in the family, and that no maintenance-fee lapse/other event altered the term. If your accused conduct post-dates 2015-09-01, the patent is expired and § 271(a) direct infringement of the expired claims is not available for post-expiration conduct — the analysis shifts entirely to whether the patent owner preserved an administratively stayable pre-expiration claim.
2. Map § 286's six-year lookback. Damages are recoverable only for infringement occurring within six years before the filing of the complaint, subject to the patent owner's ability to prove no unreasonable delay under § 287. Combined with a 2015-09-01 expiration, the actionable window is narrow and, for most defendants facing a 2026 demand, already closed by more than half a decade. Get the patent owner to state its damages period in writing early.
3. Resolve the IPR2025-00050 "'592 patent" collision before anything else. Pull the petition and the patent number from USPTO Patent Trial and Appeal Board E2E (https://www.uspto.gov/patents/ptab — PTAB E2E document retrieval) or the Banner Witcoff mirror of the institution decision. If the number is not 5,742,592, close the item. If it is, escalate immediately, because a 2025-vintage proceeding on an expired 1998 patent would be highly unusual and would tell you a great deal about who is currently asserting it.
4. If any pre-expiration exposure remains, an ex parte reexamination is the cleaner channel than an IPR. Per Federal Circuit guidance issued 2025-11-06 in In re Motorola Solutions, discretionary denial under Fintiv and the USPTO's evolving guidance is now firmly entrenched and largely unreviewable under § 314(d) (https://natlawreview.com/node/[366826](/patent/366826)/printable/pdf). For an expired patent, an IPR has limited upside anyway (no claim amendment by the patent owner, but also no claim scope to negotiate down). Ex parte reexamination — which is not subject to discretionary denial — lets you put the eight cited references plus any newly located art in front of an examiner at low cost. Note the practical catch: there is no § 315(e)(1) estoppel flowing from an ex parte reexam, and the Board/Federal Circuit have held IPR estoppel does not reach a parallel ex parte reexam, so this is a supplement, not a substitute.
5. Preserve your invalidity case in the district court, not the PTAB. With no PTAB proceeding and no estoppel, the full printed-publications/patent prior-art universe is on the table in litigation. The examiner-cited art is a good starting shelf: US 4,745,599 (random access with contention scheduling of subpacketized data and scheduled retransmission of unsuccessful subpackets) directly implicates claim 1's fragment-and-transmit-in-units concept, and US 5,606,561 (packet fragmentation for fair, efficient transmission with low packet delay) is a Motorola-internal fragmentation reference — both are worth a fresh obviousness combination in view of US 5,583,869 (dynamic allocation of wireless resources).
6. Since there is no PTAB activity, say so plainly — and explain it. The absence is a signal, and the correct reading is not "this patent is undefeated." It is "this patent was never worth attacking on the PTAB timeline." Use that to shrink the case: the patent owner cannot invoke any IPR history to bolster validity, cannot claim the claims survived scrutiny, and cannot claim estoppel against your grounds. Any argument it makes about the patent's presumed strength must rest on the 1998 examination alone.

Caveats on completeness. I did not have direct API access to PTAB E2E or Docket Alarm full-text during this pass; the negative result rests on the ODP structured block plus web verification. Two residual gaps a defendant should close directly: (i) pre-AIA inter partes reexamination (available only for patents filed before 2012-09-16 and now largely historical) and ex parte reexamination do not appear in the ODP AIA-trial block and I found no evidence of either, but they are not excluded by it; and (ii) District court and ITC assertion history for this specific patent number — my searches surfaced Motorola/Motorola Mobility campaigns on other patents and nothing tying a case number to 5,742,592. Both should be confirmed via PatentCenter's "Transactions" and "Litigation" tabs before you finalize any opinion letter.

I'll research the assignment record for US 5,742,592 through multiple sources.

Let me try to access the USPTO assignment records directly and search for the specific assignment reels.

Let me dig for the specific reel/frame records and the Pierre Dupont inventor discrepancy.

Assignment & Ownership Reconstruction — US 5,742,592

Sourcing note (read first): The Google Patents record for US5742592A (the authoritative full text provided to me) includes a Legal Events / reassignment list that I treat as the backbone of this reconstruction. Those entries give me dates, conveyance types, and assignor/assignee names. What I could not retrieve in this session are the reel/frame numbers and recorded correspondents for the two Motorola-era records and the two post-2011 records on this specific patent — the live USPTO Patent Assignment Center (https://assignmentcenter.uspto.gov/ and https://assignment.uspto.gov/patent/index.html) is not directly queryable through the search tools available here. I will not invent reel/frame numbers. Where I have a reel/frame from a batch recording that likely covers this patent, I flag it explicitly as unverified for the '592 patent. If you need the exact reels, run the Assignment Center patent-number query directly (search "5742592" → all records); that is the definitive source and takes under a minute.

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Inventors

• Both inventors are Canadian-resident (BC), and both assigned to Motorola, Inc. (Schaumburg, IL) — the U.S. parent — which is consistent with employment at a Motorola Canadian subsidiary and assignment upstream to the U.S. entity. I have not independently verified the employment relationship; this is an inference from residence + assignment, and I flag it as such.
• Anomaly to flag (contradiction with the issued face): The Google Patents reassignment log shows two Motorola-inbound records — one dated 1995-12-21 naming assignors Gerhards + Scholefield, and a second dated 1996-12-11 naming assignors Dupont, Pierre B. + Gerhards + Scholefield. But the issued patent names only two inventors (Scholefield, Gerhards). A third purported assignor, Pierre B. Dupont, appears in the assignment data yet is not a named inventor on the '592 patent. That is a genuine discrepancy, not a transcription error I introduced. Plausible explanations (all unverified): Dupont was an inventor removed by a pre-issue preliminary amendment/inventor correction; or the 1996-12-11 record is a family-level recording covering the related case (the '592's CIP sibling, US 08/560,258, issued as US 5,729,542). Do not treat Dupont as an inventor of '592 without pulling the reel. (This is consistent with the earlier section's note that the related CIP is US 5,729,542.)
• "All inventors departed within 12 months" pattern: I have no evidence either way. I found no employment-departure records, and I will not infer a fire-sale pattern from silence. The 1995 filing predates any such traceable record in the sources searched.

Family note: Both BC inventors also appear on the sibling case US 5,729,542 (application 08/560,258), the CIP listed in the '592 family. Where '592 and '542 share an inventor pair, an assignment recorded against one may appear on both records — a likely explanation for the duplicate/three-assignor entries above.

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Original assignee

• Entity on the issued patent: Motorola, Inc., Corporate Offices, 1303 East Algonquin Road, Schaumburg, Illinois 60196.
• Primary line of business: Mobile/land-mobile communications and telecommunications infrastructure — GSM base station subsystems (BTS/BSC), switching, and cellular handsets. The '592 claims (priority-based subchannel access and multi-slot packet fragmentation for GPRS) sit squarely in Motorola's GPRS/GSM infrastructure and handset product line.
• Did they ship a product embodying the claims? Very likely yes. Motorola was one of the largest GSM/GPRS infrastructure and handset suppliers of the late 1990s and shipped GPRS-capable base stations and terminals. I did not verify a specific product SKU reading on the claims; treat this as a high-confidence business inference, not a claim-chart conclusion.
• Current status of the original assignee: Motorola, Inc. no longer exists as such. In January 2011 it separated into two public companies: Motorola Mobility Holdings, Inc. (mobile devices/home) and Motorola Solutions, Inc. (public safety/enterprise). The patent record shows the split via the 2010-12-13 Motorola, Inc. → Motorola Mobility, Inc. assignment. This was a corporate spin-off/reorganization, not a fire-sale or bankruptcy.
• Assignee-field discrepancy (cross-referencing the earlier sections): Unified Patents surfaces "Motorola Solutions Inc" on this record. That is almost certainly a data artifact flowing from the 2011 Motorola Inc. split — Motorola Solutions is the other successor and did not receive this patent. The assignment chain (below) and the EP/GB register entries both point to the Mobility lineage ending at Google. I flag this because the earlier summary already noted the discrepancy; my reconstruction resolves it in favor of the Mobility → Google chain.

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Assignment timeline

Chronological, from the Google Patents reassignment log for US5,742,592. Reel/frame and recorded correspondent could not be verified for these entries in this session — flagged per line. Conveyance types are as described in the record.

• 1995-12-21 (recorded) — Reel/frame: NOT VERIFIED

  • Conveyance: Assignment of assignors' interest
  • Assignor: Ronald H. Gerhards; Christopher Scholefield
  • Assignee: Motorola, Inc. (Schaumburg, IL)
  • Correspondent: not retrieved. (Prosecution attorney/agent of record on the patent is J. Ray Wood; whether he was the recording correspondent is unconfirmed.)
  • Context: Initial inventor-to-employer assignment (routine corporate ownership capture).

• 1996-12-11 (recorded) — Reel/frame: NOT VERIFIED

  • Conveyance: Assignment of assignors' interest
  • Assignor: Pierre B. Dupont; Ronald H. Gerhards; Christopher Scholefield
  • Assignee: Motorola, Inc.
  • Correspondent: not retrieved.
  • Context: Supplementary/inventory-correcting assignment to Motorola — source of the Dupont naming anomaly discussed above; likely a family-level or inventor-correction recording, unverified.

• 2010-12-13 (recorded) — Reel/frame: NOT VERIFIED

  • Conveyance: Assignment of assignor's interest
  • Assignor: Motorola, Inc.
  • Assignee: Motorola Mobility, Inc.
  • Correspondent: not retrieved. (EP register corroborates the underlying deed backing the 2011 Motorola Inc. split.)
  • Context: Internal corporate reorganization / spin-off — Motorola, Inc.'s 2011 separation into Motorola Mobility and Motorola Solutions.

• 2012-10-02 (recorded) — Reel/frame: NOT VERIFIED

  • Conveyance: Change of name (no change in beneficial ownership)
  • Assignor: Motorola Mobility, Inc.
  • Assignee: Motorola Mobility LLC
  • Correspondent: not retrieved.
  • Context: Change of name only — the June 2012 conversion of Motorola Mobility, Inc. into a Delaware LLC (as recited in Motorola Mobility's own Federal Circuit certificate of interest, CAFC No. 13-1150). Not a transfer to a new party.

• 2014-10-28 (executed) / 2015-04-02 (recorded on this patent) — Reel/frame: NOT VERIFIED for '592; batch reels seen elsewhere include 034472/0001, 034371/0612, 034627/0001 (unconfirmed for this patent)

  • Conveyance: Assignment of assignor's interest
  • Assignor: Motorola Mobility LLC
  • Assignee: Google Technology Holdings LLC, 1600 Amphitheatre Parkway, Mountain View, CA 94043
  • Correspondent: not retrieved. (For the sibling Motorola Mobility → Google Technology Holdings batch recorded 2014-11-26, the correspondent of record is Kristin J. Achterhof, Katten Muchin Rosenman LLP, 525 West Monroe St, Chicago, IL 60661 — same firm that appears as Motorola trademark correspondent in TTAB filings. I flag this as a candidate correspondent for the '592 record but cannot confirm the reel.)
  • Context: Portfolio-consolidation transfer inside the Google corporate family — Google acquired Motorola Mobility in 2012; the Motorola Mobility patent portfolio was swept into Google's dedicated IP-holding entity. Executed 2014-10-28; EP/GB registers record the same deed date (28.10.2014) across the whole Motorola Mobility portfolio.

• 2015-09-01 — Anticipated expiration (no further assignment; no post-Google transfer recorded). The chain terminates at Google Technology Holdings LLC.

If the Assignment Center shows no records for a given link: it does not — records exist for every link above. The only gap is my inability to read the reel/frame + correspondent fields through the tools available. That is a data-access limitation, not the absence of a record.

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Timeline diagram

timeline
    title Ownership of US 5742592
    1995 : Application filed Sep 1
         : Inventors assign to Motorola Inc Dec 21
    1996 : Second Motorola assignment Dec 11
    1998 : Patent issues Apr 21
    2010 : Motorola Inc to Motorola Mobility Inc
    2011 : Motorola Inc splits into two companies
    2012 : Google acquires Motorola Mobility
         : Name change to Motorola Mobility LLC
    2014 : Google sells handset unit to Lenovo
         : Google retains patent portfolio
    2015 : Transfer to Google Technology Holdings
         : Patent expires Sep 1

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NPE / troll-pattern signals

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Verdict

Defensive / non-asserting.

The ownership chain runs inventors → Motorola, Inc. (1995/1996) → Motorola Mobility, Inc. (2010-12-13) → Motorola Mobility LLC, change of name only (2012-10-02) → Google Technology Holdings LLC (executed 2014-10-28, recorded 2015-04-02), and it terminates in an operating company's IP-holding entity, with no transfer to a licensing-only shell, no asserter on any NPE list, no bankruptcy sale, and no suit naming the patent before its 2015-09-01 expiration. That said, I must be candid about one definitional friction: Google Technology Holdings LLC is a corporate holding subsidiary, not a formal defensive aggregator like RPX/AST/LOT/Unified/OIN — so this verdict is the least-wrong fit rather than a textbook match, and the alternative if you require strict category adherence would be "Insufficient data" (which is not warranted, since records exist). The two strongest drivers of "no NPE" are the 2012-10-02 change-of-name entry (pure reorg, no new party) and the 2014-10-28/2015-04-02 move to a Google subsidiary executed as part of Google's public, product-oriented retention of the Motorola portfolio.

Two things I could not deliver and will not fake: (1) the reel/frame numbers for each link, and (2) the recorded correspondents for the Motorola-era and Google-era records. Verify both at the USPTO Patent Assignment Center (https://assignmentcenter.uspto.gov/ — query patent number 5742592; legacy portal mirrors it at https://assignment.uspto.gov/patent/index.html). Those fields would either confirm or dissolve the "repeat correspondent" signal, which is the one signal I left unclear rather than calling.

Cross-reference flags for the earlier sections: (a) the Dupont assignor is a real anomaly and is not reconciled by the issued inventor list; (b) the earlier "Motorola Solutions Inc" assignee display is a split-era artifact and is superseded by the Mobility → Google chain; (c) the earlier date discrepancy (user-supplied vs. fetch date) does not affect any assignment event date above.

I'll research each prior-art reference cited on the face of US 5,742,592. Let me run targeted searches on the key references.

Let me research the remaining cited references to ground their descriptions.

Prior-Art Analysis — US 5,742,592 ("Method for communicating data in a wireless communication system")

Scope, method, and caveats (read first)

• Source of truth: The authoritative full text you supplied (Google Patents mirror of the USPTO record, https://patents.google.com/patent/[US5742592A](/patent/US5742592A)/en). The patent's own "Patent Citations (8)" table is the examiner-cited art list I work from below. I did not auto-correct any number.
• This session's limits: I reached the tool-call limit after retrieving full/partial text for five of the eight references. For US 5,161,194 (Ujiie), US 5,440,545 (Buchholz), and US 5,648,967 (Schulz) I could not pull full claim/description text; their entries are based on the '592 citation table (title, assignee, dates) plus general knowledge, and are explicitly flagged as provisional. I did not retrieve a direct USPTO PatentCenter/PTAB full-text query in this session; the citation table in the supplied record serves as the USPTO citation list.
• Anticipation standard: § 102 anticipation requires a single reference disclosing every element of a claim, arranged as claimed. Where a reference discloses only some elements, it is § 103 (obviousness) material, not § 102 art. That distinction drives the conclusions below.
• Consistency with earlier sections: No contradiction with the prior "summary/litigation" sections. (Earlier flag retained: the supplied current date, April 26 2026, differs from the 2026-09-29 fetch stamp on the source — immaterial to the art analysis.)

The eight examiner-cited references at a glance

All eight bear the examiner-citation asterisk in the '592 record, i.e. the examiner considered them during prosecution.

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Reference-by-reference

1. US 4,745,599 — Raychaudhuri (General Electric), granted 1988-05-17; filed/priority 1987-01-05

Title: "Random access communication system with contention scheduling of subpacketized data transmissions and scheduled retransmission of unsuccessful subpackets." (https://patents.google.com/patent/US4745599)

Description (confirmed from full text): A satellite/Tx-Rx network in which a message is subpacketized into a sequence of subpackets that contend on an asynchronous random-access basis; subpackets that collide are retransmitted at random times, while successful subpackets are scheduled for collision-free data-packet transmission. Explicitly discusses ALOHA/slotted-ALOHA and "stacking" of scheduled transmissions.

Relevance to '592: Discloses the generic notions of (i) breaking a message into plural subpackets/sub-data-units and (ii) scheduled, re-scheduled transmission of those units. It does not disclose: requesting plural subchannels of a wireless communications resource; receiving a first and subsequent allocations of a designated subchannel; encoding each PDU into encoded PDUs (E-PDUs); TDMA/CDMA subchannel multiplexing; or priority-based deferral.

Potential § 102 anticipation: None in full. At most, it is circumstantial support for the "fragment into plural data units" element of claim 1 and the asynchronous/scheduled-retransmission backdrop relevant to claim 9's "asynchronously" concept. As a standalone reference it does not anticipate claims 1–12.

2. US 5,161,194 — Ujiie (NEC), granted 1992-11-03; filed/priority 1989-07-31

Title: "Satellite communications system operating in asynchronous mode for central-to-terminal station transmission."

Description (provisional — full text not retrieved this session): A satellite system in which a central station transmits to terminal stations in an asynchronous mode.

Relevance to '592: Historically relevant to the concept of asynchronous central-to-terminal transmission, which maps loosely to the asynchrony language of claim 9 and the general network topology, but it does not address packet fragmentation, subchannel request/allocation, encoding, or priority.

Potential § 102 anticipation: None. No claim of the '592 appears anticipated. Treat this conclusion as provisional pending full-text review.

3. US 5,260,989 — Jennes et al. (IBM), granted 1993-11-09; filed/priority 1992-05-21

Title: "Method and system for enhanced data transmission in a cellular telephone system." (https://patents.google.com/patent/US5260989)

Description (confirmed from full text): "A data stream is divided into relatively short data packets which are sequentially transmitted via alternate adjacent buffer voice channels in a predetermined and repetitive order," using a spread-spectrum transceiver across multiple adjacent buffer channels, with synchronization packets to reassemble at the receiver.

Relevance to '592: Notably close to the distribution concept — dividing a data stream into plural short data packets and spreading them across plural channels. It therefore touches the "fragment a data packet into plural data units" step of claim 1 and the plural-channel/multi-subchannel transmission idea. However it concerns frequency-division buffer voice channels, and discloses no request-for-subchannel, no first/subsequent allocation periods, no E-PDU encoding, and no priority deferral. It also arguably supports the cellular/"CDPD radio channel" context of claim 4.

Potential § 102 anticipation: No full anticipation. It does not disclose the allocation/re-allocation/priority architecture that distinguishes the '592 claims. Best viewed as § 103 material for the fragmentation-and-distribute element.

4. US 5,440,545 — Buchholz et al. (Motorola), granted 1995-08-08; filed/priority 1993-08-02

Title: "Packet delivery system."

Description (provisional — full text not retrieved this session): A Motorola packet-delivery method in which packet data is delivered over communication resources (fragmentation/scheduling of packet delivery). Not to be confused with US 5,555,266 below; it is a distinct Buchholz-family reference.

Relevance to '592 / § 102: Because it was granted only three weeks before the '592 filing, it cannot be § 102(b) art; it is available, if at all, as § 102(a)/(e) art. Based on title/context it is relevant to packet fragmentation and delivery over allocated resources, but I cannot confirm it discloses any specific '592 claim element. No § 102 anticipation identified; provisional pending full-text review.

Common-ownership note (applies to refs. 4–7): These are Motorola references, as is the '592 (Motorola, Inc.). Under pre-AIA § 103(c), § 102(e)-only art that was commonly owned at the time of invention is disqualified for obviousness but not for anticipation. This materially weakens any § 103 combination built solely on refs. 4–7, and is worth flagging for any validity analysis.

5. US 5,555,266 — Buchholz et al. (Motorola), granted 1996-09-10; filed/priority 1993-10-04

Title: "Method for reducing transmission delays in a packet transmission system." (https://patents.google.com/patent/US5555266)

Description (confirmed from full text): A TDMA packet system in which remote units queue access requests and the controller issues resource grants; the remote unit applies a grant to its oldest request and, where the granted resources are insufficient, "transmit[s] a number of data packet fragments as specified in the grant." The controller, on receiving data, identifies missing data, determines whether resources are available, and grants resources for retransmission (claim 11 of that patent). Data packets may be "separat[ed] … into a plurality of data packet fragments" (its claim 3).

Relevance to '592: This is the closest reference to the request→grant→(partial grant)→fragment-and-transmit architecture and to the network-side re-grant flow of '592 claim 11. Specifically:

• Requests for resources, grants of resources, and fragmentation into fragments map onto claim 1's requesting/allocating and fragmentation steps and claim 11's receive-request/transmit-allocation-1/receive-portion flow.
• The partial grant ("a number of data packet fragments as specified in the grant," where the grant is smaller than the request) is conceptually analogous to '592 claim 7's "receive an allocation of n … where n is a number between one and the m subchannels requested."

Potential § 102 anticipation:

• Claim 7 — arguable partial match but not full anticipation. '266 does not disclose requesting "m plural subchannels of a communications resource," nor encoding each of the n PDUs into n E-PDUs, nor per-subchannel E-PDU transmission. So no complete anticipation.
• Claim 11 — not anticipated. '266's controller "monitors" for missing data, not (as claim 11 requires) for higher-priority requests for subchannel allocations from further units. The priority-monitoring/re-allocation limitation is absent.
• Best characterized as strong § 103 material (with the § 103(c) common-ownership caveat above).

6. US 5,583,869 — Grube et al. (Motorola), granted 1996-12-10; filed/priority 1994-09-30

Title: "Method for dynamically allocating wireless communication resources." (https://patents.google.com/patent/US5583869)

Description (confirmed from full text): In a TDM system, a communication unit requests a first number of wireless communication resources; a central controller determines a system grade of service for the message and allocates a second number of resources, matching resources to need and availability; the unit can determine the first number based on message type (e.g., a medical image needs 2+ time slots), and the controller "can allocate the second number … in response to a request from the communication unit."

Relevance to '592: This is the strongest reference for the "request m, receive n" concept of claim 7 and for the desired-throughput/grade-of-service concepts of claim 2 and the priority framework generally. The first-number-requested → second-number-allocated structure is directly on point for claim 7's "requesting an allocation of m … receiving an allocation of n."

Potential § 102 anticipation:

• Claim 7 — close, but not a complete anticipation. '869 is missing the encoding into E-PDUs, the fragment-into-n-units sized to the granted n, and the explicit "n between one and m" subchannel-of-a-communications-resource framing. Under a strict element-by-element test it does not anticipate; it is the leading § 103 combination reference against claim 7 and claim 2.
• Claim 2 — relevant. '869's "determine the first number … based on the message type" is close to "determining the desired throughput rate," but claim 2 depends from claim 1, which '869 does not otherwise meet.
• Common-ownership § 103(c) caveat applies.

7. US 5,606,561 — Scheibel et al. (Motorola), granted 1997-02-25; filed/priority 1995-07-28

Title: "Method, device/microprocessor, and computer software for providing packet fragmentation for fair, efficient downlink transmission with low packet delay." (https://patents.google.com/patent/US5606561)

Description (confirmed from full text): A base site fragments a data packet into a number of fragments based on the number of available time slots and the hardware capability of the target subscriber unit, assigns each fragment to an available time slot, further divides fragments into segments sized to a TDMA time slot, and transmits the segments on the assigned time slots — with the number/location of available slots varying over time.

Relevance to '592: This is the closest single reference on the packet-fragmentation-into-multiple-TDMA-time-slots (subchannels) element. It maps onto:

• Claim 1 — "fragmenting a data packet into plural data units (PDUs)" and "communicating each of the E-PDUs via one of the … designated subchannels."
• Claim 2 — fragmentation based on available resources/hardware capability (relevant to the "determining the desired throughput rate and fragmenting accordingly" concept).
• Claim 6 — TDMA-multiplexed subchannels.

Potential § 102 anticipation: No full anticipation. Critical gaps: '561 is a downlink, base-site-centric scheme with no subscriber request for plural subchannels, no first/subsequent limited allocation periods, no E-PDU encoding step, and no priority-based deferral. It is, however, the strongest § 103 reference for the fragmentation/multi-slot element, and the § 103(c) common-ownership caveat applies.

8. US 5,648,967 — Schulz (Siemens), granted 1997-07-15; filed/priority 1994-03-07

Title: "Method and arrangement for transmitting information in a digital radio system."

Description (provisional — full text not retrieved this session): A Siemens method/arrangement for transmitting information in a digital radio system (time-slot/packet-oriented digital radio context inferred from title and prosecution context).

Relevance to '592 / § 102: General digital-radio information-transmission context art; available only as § 102(e) art (filed 1994-03-07, granted 1997-07-15). I cannot confirm any specific '592 claim element is disclosed. No § 102 anticipation identified; provisional pending full-text review.

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Overall assessment

No single one of the eight examiner-cited references appears to anticipate any of the four independent claims (1, 7, 10, 11) or their dependents under § 102, based on the disclosures available. The claimed invention's core is a combination — (a) fragment + encode into E-PDUs, (b) request plural subchannels, (c) receive a first allocation plus subsequent re-allocations of limited duration, and (d) priority-based deferral/re-allocation — and the cited art distributes these elements across several references rather than concentrating them in one.

Most relevant prior art (ranked), and what each is best used for:

1. US 5,606,561 (Scheibel) — fragmentation of a packet across multiple TDMA time slots/subchannels (claim 1 fragmentation/dispatch; claim 2; claim 6).
2. US 5,583,869 (Grube) — request first number of resources / receive second number; grade-of-service (claim 7 "request m / receive n"; claim 2; priority framework).
3. US 5,555,266 (Buchholz) — resource grants, partial grants, fragmentation, and controller-side grant/re-grant (claim 1 requesting/allocating; claim 7 partial-grant analogy; claim 11 network-side flow, but missing the "monitor for higher-priority requests" limitation).
4. US 5,260,989 (Jennes) — divide a data stream into short packets transmitted across plural channels (claim 1 fragmentation/distribution; claim 4 context).
5. US 4,745,599 (Raychaudhuri) — subpacketization + scheduled/retransmitted transmission (background on fragmentation/scheduling).
6. US 5,440,545 (Buchholz) — packet delivery over resources (provisional; background).
7. US 5,161,194 (Ujiie) — asynchronous central-to-terminal satellite transmission (claim 9 asynchrony context only; provisional).
8. US 5,648,967 (Schulz) — digital-radio information transmission (general context; provisional).

Statutory categories: refs. 1–3 are § 102(b) art (granted >1 year before the 1995-09-01 filing); refs. 4–8 are, at most, § 102(a)/(e) art, with ref. 4 (US 5,440,545) not qualifying under § 102(b). For refs. 4–7 (all Motorola, the '592's assignee), pre-AIA § 103(c) common ownership would disqualify § 102(e)-only art from § 103 obviousness (though not from § 102 anticipation) — a point that materially affects any obviousness theory built on the Motorola references alone.

Practical bottom line: Any § 102/§ 103 challenge to the '592 independent claims would most plausibly rest on a § 103 combination led by Scheibel ('561) and/or Grube ('869) plus Buchholz ('266) and/or Jennes ('989) — not on any single reference. The strongest single-reference element matches are: Scheibel for fragmentation-over-multiple-time-slots; Grube for "request m / receive n"; and Buchholz '266 for the network-side grant/re-grant flow (subject to the priority-monitoring gap in claim 11).

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Explicit uncertainties / limits

• Three references (US 5,161,194, US 5,440,545, US 5,648,967) were not fully retrieved in this session (tool-call limit reached). Their "potential anticipation" conclusions are provisional and should be re-verified against full text. I have not fabricated their disclosure content.
• My anticipation conclusions are analytical opinions on the reference disclosures as retrieved, not legal conclusions; a formal § 102/§ 103 validity opinion requires element-by-element claim charts against the complete reference texts and the applicable pre-AIA statutory framework (the '592 is a pre-AIA patent; the AIA §§ 102/103 do not govern it).
• I did not query a paywalled full-text patent database (e.g., PatentCenter/PTAB full-text, LexisNexis) in this session; the citation list above is drawn from the authoritative '592 record you supplied. If you want, I can next produce element-by-element claim charts mapping claim 1 and claim 7 against Scheibel '561, Grube '869, and Buchholz '266.

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

Good material. Let me pull the remaining cited references relevant to the priority/deferral and access-request limitations.

Obviousness Analysis — US 5,742,592 under 35 U.S.C. § 103

Building on the prior sections' claim mapping and prior-art list; not repeating the bibliographic or litigation findings.

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1. Analytical framework and a threshold point

Under Graham v. John Deere and KSR Int'l v. Teleflex, the § 103 inquiry is: (a) scope/content of the prior art, (b) differences between the art and the claims, (c) PHOSITA level, (d) objective indicia. Where the claim is "the predictable use of prior art elements according to their established functions," it is obvious.

Threshold drafting point that drives the whole § 103 analysis. Claim 1 recites "an allocation of at least one designated subchannel" but then requires "communicating during the first period of time a first E-PDU … via the first designated subchannel and a second E-PDU … via the second designated subchannel." This internal inconsistency (already flagged in the summary section) is outcome-determinative here:

• Broad construction (one subchannel, sequential transmission): Claim 1 collapses toward Grube/Raychaudhuri alone.
• Narrow construction (two-or-more subchannels transmitting simultaneously): Claim 1 requires the Scheibel-style parallel multi-slot fragment transmission.

A defendant should plead both: the broad reading is obvious over fewer references; the narrow reading is obvious over the Scheibel + Grube + Raychaudhuri combination below.

PHOSITA (c. Sept. 1995): a BS/MS-level engineer with 2–3 years' experience in TDMA/cellular packet-data radio resource management, familiar with GSM/GPRS, ALOHA-family MAC protocols, FEC coding, and multi-slot data.

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2. What the cited art actually teaches

Also of record and usable: the Raychaudhuri Selective Reject ALOHA article, IEEE Trans. Comm., Feb. 1984, pp. 148–154 (cited inside the '599). And the '592's own background section is an admission: "one proposal has been to allow for the use of multiple subchannels (e.g., 2 or more time slots per frame)" — i.e., multi-subchannel operation is conceded prior art.

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3. Claim-by-claim § 103 combinations

Claim 1 — primary combination: Scheibel + Grube + Raychaudhuri (optionally + Jennes)

• Fragment packet into PDUs → Scheibel ("fragmenting a data packet … into a number of fragments"); Raychaudhuri (subpacketization); '266 ("a packet may require fragmentation").
• Encode each PDU into E-PDUs → not squarely claimed by any one reference, but FEC/codeword encoding of a burst is a textbook known technique (and the '592's own spec equates the E-PDU with "an error correction encoded packet data unit"). This is the classic KSR "known technique" prong.
• Request plural subchannels → Grube (request a first number of resources; "a medical image may require two or more time slots").
• Receive allocation of ≥1 subchannel for a first period; subsequent allocations for subsequent periods → Grube (dynamic allocation/reallocation "as necessitated by changing service requirements") + Raychaudhuri (short scheduled grants, multiple reservation cycles, "stacking" of successive scheduled transmissions).
• Communicate each E-PDU on a designated subchannel — first E-PDU on the first subchannel and second E-PDU on the second during the first period → Scheibel, almost verbatim: fragments "in transit on m different time slots at a particular point in time."

Motivation. Scheibel and Grube are both Motorola, both filed within ~10 months of each other, both directed to the same problem (getting high-throughput packet data onto TDMA time slots), and both expressly contemplate giving one unit multiple slots. Raychaudhuri is analogous packet-data MAC art supplying scheduled, time-limited grants and the deferral mechanism. Jennes supplies the reason to spread a packet's units across channels: minimizing the interference/fading that the '592 background itself identifies as the drawback of naive multi-slot transmission ("a fade may corrupt 2 or more time-slot periods of data in a row"). The '592's asserted benefit — "the effect of the fragmenting and transmission on different subchannels is similar to that of interleaving" — is the predictable consequence of Jennes' known channel-hopping/interleaving principle applied to Scheibel's fragment-to-slot assignment. That is the definition of a predictable use of known elements.

Claims 2–6 (dependents)

Claim 7 — most vulnerable claim: Grube + Scheibel (and a serious § 102(e) question over Grube alone)

Claim 7 is "request m, receive n (1 ≤ n ≤ m), fragment into n units, send each on one of the n subchannels."

• Grube discloses the request-m / allocate-n relationship nearly as claimed: the unit requests a first number, and the controller "allocate[s] a second number" matched "to the needs of the communication unit with the resource availability," after which the unit "transmit[s] portions of [the] message … via resources."
• Scheibel supplies "fragment … into n units based on the number of available time slots" — i.e., fragmenting to the granted count rather than the requested count.

Combining them is a one-step, same-field, same-problem substitution. Flag: the closeness of Grube alone (which contemplates both a request-count/allocation-count mismatch and transmitting "portions of [a] message" over the allocated resources) raises a genuine anticipation question under § 102(e), which a defendant should plead in the alternative. I did not retrieve Grube's full claim set in this pass, so verify the claim language before asserting anticipation.

Claim 8 — two-stage access request with capability parameter

Raychaudhuri discloses the two-stage structure directly: a short reservation request packet (ID, overhead bits) followed by the scheduled transmission, with the data packet carrying D_i/length. Grube supplies the request carrying message type and message length. Scheibel supplies the hardware capability parameter ("a hardware capability of the … subscriber unit for transmitting/receiving a plurality of time slots") — which is exactly claim 8's "parameter including multiple subchannel transmission capability." Identifiers/authentication/grade-of-service in an access request are standard GSM/GPRS RACH practice.

Claim 9 — asynchronous transmission of the n E-PDUs

Raychaudhuri is expressly an asynchronous system ("contend on an asynchronous random access basis"); US 5,161,194 (Ujiie) is likewise directed to asynchronous operation. Asynchrony is thus taught in the same field.

Claim 10 — apparatus mirror of claim 1

Same combination as claim 1, plus a transceiver and programmed processor. Grube discloses "communication units 101-102" with a controller and radios; Scheibel discloses a base-site "device/microprocessor" with a fragmenter, time-slot assignment unit, and RF circuitry. Structuring known method steps as a programmed transceiver/processor is routine (the '592 spec itself concedes the circuits "may be implemented in a variety of ways, such as … programmed processors, ASICs … DSPs").

Claim 11 — infrastructure side: request → grant → receive first portion → monitor for higher priority → re-grant → receive second portion

This is the closest claim to a single reference — US 5,555,266 ('266):

• Controller receives access requests and issues resource grants ✔
• Receives a partial data packet (in '266's framing, "lost, corrupted or otherwise unintelligible data"), then identifies the missing portion and "grant[s] sufficient resources for retransmission," i.e., receives a first portion, grants again, receives a second portion ✔
• Priority monitoring: '266 claim 13 schedules resources to "service retransmit requests stored in the second memory queue prior to servicing the access requests stored in the first memory queue" — an express priority hierarchy ✔

Add Grube (controller monitors system state and allocates by "system grade of service for a message," reallocating "as necessitated by changing service requirements or system capabilities") for the "monitor for higher-priority requests … if none, transmit a second allocation" step, and Raychaudhuri for the "limited-duration scheduled grant followed by re-grant" architecture.

Claim 12 — defer first unit, serve higher-priority second unit, then re-allocate to first

• Deferral/interruption → Raychaudhuri's "stacking": a scheduled transmission is deliberately delayed so an earlier scheduled transmission can complete without collision. (The '592 inverts the priority direction, but the mechanism — holding a partially-served transmission and resuming it — is the same.)
• Priority-based service to the second unit → '266 claim 13 (priority re-ordering of queued requests) + Grube (grade-of-service-based allocation).
• Re-allocate to the first unit to finish the packet → '266's re-grant-after-partial-receipt mechanism.

The combination is: '266 (host controller + partial-receipt re-grant + priority ordering) + Raychaudhuri (defer-and-resume scheduling) + Grube (grade-of-service allocation). All three are analogous packet-data resource-allocation art.

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4. Motivation-to-combine summary (KSR rationales)

1. Same field / same problem. All of Raychaudhuri, '266, Grube, Scheibel and Jennes address bandwidth-efficient packet-data transmission over shared radio resources. No "field of endeavor" or "reasonably pertinent" gap.
2. Same assignee for the three closest references. Scheibel, Grube and '266 are all Motorola — like the '592. Common development context is a recognized (if non-dispositive) motivation. Caution: verify the pre-AIPA § 103(c) issue (below).
3. Known techniques. FEC/codeword encoding, TDMA/FDMA/CDMA multiplexing, and channel-to-fragment assignment are all established.
4. Predictable result. The '592's core asserted advantage — fading immunity from interleaving fragments across subchannels — is the expected result of applying Jennes' channel-switching/interleaving principle to Scheibel's fragment-to-slot assignment.
5. Design need. The '592 background admits both the multi-subchannel proposal and its fading drawback; that admitted problem supplies the very motivation to interleave across subchannels.

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5. Patent owner's best nonobviousness arguments — and the rebuttal

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6. Caveats and required verification

1. § 103(c) / common ownership. Scheibel, Grube and '266 are § 102(e) art (filed before, published/granted after the '592's 1995-09-01 filing). For a 1995-filed patent, the pre-AIPA version of § 103(c) covered only § 102(f)/(g) art, not § 102(e) — meaning common Motorola ownership would not disqualify them. Verify the statute's temporal application before relying on this in a brief.
2. Three cited references not retrieved in full: US 5,440,545 (Buchholz), US 5,648,967 (Schulz), and US 5,161,194 (Ujiie). I used only their titles. I am not asserting what they disclose; a defendant should pull the full texts, since '545 (Motorola packet delivery) and '967 (Siemens digital radio) could materially strengthen the claim 11/12 and claim 1 attacks.
3. Anticipation vs. obviousness. Claim 7 over Grube alone, and claim 11 over '266, are close enough that § 102 should be pleaded in the alternative. I did not retrieve the full claims of Grube or '266 in this pass; verify.
4. Claim 1 construction. The "at least one" vs. "first/second designated subchannel" inconsistency must be resolved before the § 103 case is finalized — the required reference set differs materially by construction.
5. This analysis rests on the eight examiner-cited references and the family. I found no evidence that any un-cited art was considered, so this is a lower bound on the available § 103 case, not an upper bound.