US 6837436

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

US Patent 6,837,436 — Summary

Searches run (2026): Google Patents full text, the USPTO grant PDF (patentimages), uspto.report grant record, FreePatentsOnline, Justia, plus targeted queries for CAFC/Federal Circuit 2026 activity on this number. Note that Google Patents renders the number as US6837436B2 / US 6,837,436 B2; all identifiers below are reproduced literally from the sources.

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1. Bibliographic data

Priority chain (as listed): CIP of App. 09/487,923 ("Portable shopping fulfillment system," filed Jan. 19, 2000) → division of 08/866,690 (filed May 30, 1997, abandoned) → CIP of 08/780,023 (Dec. 20, 1996, now US 6,084,528, "Intranet scanning terminal system") → CIP of 08/706,579 (Sep. 5, 1996, now US 5,825,002, "Device and method for secure data updates in a self-checkout system"). Continuation family includes US 7,065,263 and US 7,195,157 (from App. 11/424,370), and US 2007/0210155 A1.

2. Abstract (verbatim, from the printed grant)

"The present invention relates generally to a consumer interactive shopping and marketing system. The system includes a portable data terminal for communicating information over a communication network. The present system has aspects that may be used within a shopping establishment or at a user's home."

3. Litigation / docket check — important caveat

• CAFC 2026 dockets: I found no Federal Circuit proceeding in 2026 involving patent 6,837,436. My searches surfaced only unrelated 2026 CAFC opinions and Rule 36 judgments (e.g., Spero v. Mercedes-Benz USA, Nos. 2025-1470/1472; Contour IP Holding v. GoPro, No. 2026-2012; US Patent No. 7,679,637 LLC v. Google). None reference 6,837,436. This is consistent with the patent having expired/adjusted expiration in 2017. Treat this as a negative search result, not proof of absence — I did not have direct PACER/CM-ECF docket access, and 2026 CAFC docket text is not fully indexed by the sources I could reach.
• District court: Google Patents' litigation panel lists a case filed in Texas Eastern District Court, case 4:21-cv-00559 (data attributed to Unified Patents). That is a district-court matter, not an appeal, and I could not verify its current posture.
• A Korean government technology-report listing (6837436) Consumer interactive shopping system also appears, confirming third-party indexing of this number.

4. Plain-language overview of the independent claims

There are 15 independent claims: 1, 10, 22, 33, 36, 44, 52, 57, 62, 65, 70, 75, 80, 85, 99. (Claim text below is from the uspto.report grant transcript; wording is reproduced without correction, including its grammatical quirks.)

1. Claim 1 — Core in-store/at-home marketing system. A wireless shopping device with a scanner and a product-list memory that works in either "store mode" or "out of store mode"; a comprehensive product database; and a central host reachable through an intermediate consumer presentation device, with a messaging agent that picks which messages to show the customer. The intermediate device correlates the customer's product list with the database and displays an "enhanced presentation."
2. Claim 10 — Behavior-driven in-store messaging. Wireless network + wireless shopping device (reader + display) + a customer database of shopping-behavior characteristics that is updated in real time as the customer scans + a store host whose messaging agent selects and sends a message correlated to that behavior characteristic.
3. Claim 22 — Two-device (scanner + cart-mounted display) correlated-product messaging. A first shopping device (reader/transmitter) and a second device latched to a shopping cart with receiver, radio and display; a product profile database with correlation data linking each product ID to related products; and a host that messages the customer about correlated products when an ID is registered.
4. Claim 33 — In-store vs. out-of-store delivery prompting. Same wireless device/host/messaging structure, distinguished by the requirement that in "out of store" mode the device asks the customer to select a delivery method for the products, while in "in store" mode it does not.
5. Claim 36 — Kiosk-linked, customer-profile messaging. A shopping device with reader, communications port, stored customer ID and display; a kiosk that links to the device; a host with a customer database that selects messages correlated to that customer's information; plus a triggering agent that decides when a message is displayed (claims 41–43 tie triggers to scanning, customer location, or time of day).
6. Claim 44 — Kiosk-linked, product-correlation messaging. Same kiosk architecture, but the selected message contains information about a product correlated to the product ID just registered, sourced from a product database with correlation data.
7. Claim 52 — Cradle-linked, behavior-based messaging. Replaces the kiosk of claim 36 with a cradle (claim 53 lets the cradle be built into a kiosk; claim 54 puts that kiosk on a store end cap).
8. Claim 57 — Cradle-linked, product-correlation messaging. Cradle analogue of claim 44.
9. Claim 62 — Home/remote virtual-store system. A wide-area-network remote terminal with a GUI showing products arranged as "virtual aisles and virtual shelves" with promotional messages on those aisles, plus a product selector; and a merchant host that receives a customer ID and selects promotions correlated to that customer's stored information (claims 63–64 add 3-D representations and a mouse-based selector).
10. Claim 65 — Manufacturer/distributor surplus-inventory discounting. A method where a manufacturer/distributor with indirect sales to consumers on wireless shopping devices computes an inventory surplus, calculates a discount as a function of that surplus, and transmits it to the devices for customer notification.
11. Claim 70 — Store-side version of the same. Identical method steps, performed by a store with a host computer.
12. Claim 75 — Behavior-category targeting loop. A method of classifying customers into a behavior category based on scanned selections, associating messages with the category, transmitting them to devices in that category, monitoring selections in real time, and modifying the database accordingly (claims 77 and 97 specify the two-piece handheld + cart-mounted-display configuration).
13. Claim 80 — Message-frequency "control value" method. Computes a message control value, compares it to a threshold, displays the message only if the value is below threshold, monitors the customer's response, and adjusts the value based on that response (claims 83–84 tie the threshold to the customer's chosen message volume and to a discount for accepting messages).
14. Claim 85 — Shopping-list vs. store-inventory method. Stores an electronic shopping list on the device, gives the host access to an inventory list, generates a product availability list of items common to both, and provides it to the customer (claims 90–93 add store-layout ordering, locational help, display and kiosk printing).
15. Claim 99 — Weight-based self-checkout security method. In a self-scanning checkout where items go into multiple bags: a clerk rescans selected items, the system computes each bag's net weight excluding those items, compares it to the recorded weight of the unrescanned self-scanned items, and disallows the transaction if the net weight could not have been attained from that list (claims 103–105 add a probability determination and a shopper-security-record factor).

Dependent claims worth noting as they carry specific commercial embodiments: claim 3 (display at least 6″ × 6″), claims 4/11/23 (location tracking agent), claim 12 (location inferred from the scanned product's location in a product-location database), claims 13–14/25 (stored payment method; automatic charge to credit account on completion of selection), claims 17/27 (home docking station), claims 18/28 (manufacturer/distributor remote computer), claims 19–21/29–32 (kiosk upload/download), claim 34 (message selection via an inference engine), claim 35 (message selection based at least partly on chance), and claim 39/47 (kiosk uploads recipes).

5. Technical disclosure, in brief

The specification describes a handheld wireless terminal with an integrated machine-code reader (laser scanner, CCD/CMOS imager, or RFID reader), a graphics/touch display, microphones/speaker for telephony, an EAS tag deactivate/reactivate circuit, location-tracking circuitry (GPS, RFID, or access-point triangulation), and a radio (e.g., Symbol's SPECTRUM24® PCMCIA Type II card over an IEEE 802.11 frequency-hopping LAN, with CDPD WAN and Bluetooth short-range options). Terminals may be store-owned (dispatched from a dispenser with locking slots, flashing lights and a self-diagnostic bar-code scan) or customer-owned (PDA, cell phone, key fob such as CS-1504/CS-2000). The system includes kiosks, cradles/batch mode, product-profile and customer-profile databases (FIGS. 16–21, with replenishment frequency, price sensitivity, product links, time/location stamps, discounts offered vs. applied), a messaging agent with rules-based/inference-engine selection, virtual 3-D store layouts for home ordering, order collection and delivery tracking, self-bagging with bag bar codes, and the statistical weight-based audit described in claim 99. The background cites Dutch Patent Application 9002296 and U.S. 5,468,942 (Oosterveen) as prior self-scanning systems, and incorporates U.S. 5,877,485 and 6,092,725 (security methodologies) by reference.

6. Explicit uncertainties

• CAFC 2026: no evidence found of any 2026 Federal Circuit appeal involving 6,837,436. I cannot certify a negative from the sources available.
• Litigation status: the Google Patents panel cites T.E.D. Tex. 4:21-cv-00559 via Unified Patents third-party data; I did not confirm it from a primary court record and it is unrelated to the 2026 CAFC queries.
• Certificate of Correction: one exists, but I did not read its substantive corrections (only the header pages surfaced); the corrected claim text may differ in detail from the transcript above.
• Assignee history: security interests were recorded to JPMorgan Chase (2005) and Morgan Stanley Senior Funding (2014), with releases in 2014 and 2015, and a 2015 name change to Symbol Technologies, LLC. Current ownership should be confirmed from the USPTO Assignment database rather than inferred.

Sources: https://patents.google.com/patent/US6837436/en · https://patentimages.storage.googleapis.com/bc/9e/52/17091e88b5dd64/US6837436.pdf · https://uspto.report/patent/grant/6837436 · https://FreePatentsOnline.com/6837436.html · https://patents.justia.com/patent/20070210155 · https://www.cafc.uscourts.gov/opinions-orders/

I'll research litigation involving US patent 6837436 using multiple sources.

Let me dig into the specific litigation reference found and search additional sources.

Let me search the specific case number and additional litigation databases.

Litigation Involving U.S. Patent No. 6,837,436

Important framing note: I applied your strict rule — I treated "6837436" literally and excluded results for other patents that share a similar trailing sequence. In particular, I discarded search hits referencing a "'743 patent" (e.g., the Bardy Diagnostics patent in Vital Connect v. Bardy Diagnostics, IPR2023-00381, and the InfoGation patent in InfoGation Corp. v. ZTE/HTC/Huawei, S.D. Cal. Case No. 16-cv-01901), and the Instacart/Consumeron PTAB matters (IPR2023-00865). None of those involve U.S. 6,837,436 and none should be attributed to it.

Confirmed litigation

One case is documented on the authoritative Google Patents record for US6837436B2, which carries a litigation entry sourced from Unified Patents' Litigation Data:

Source / citation: Google Patents, US6837436B2, "litigation" field, published with the entry "US case filed in Texas Eastern District Court … https://portal.unifiedpatents.com/litigation/Texas%20Eastern%20District%20Court/case/4%3A21-cv-00559", attributed to "Unified Patents Litigation Data," licensed CC-BY 4.0. (https://patents.google.com/patent/[US6837436](/patent/US6837436)/en)

What I could not confirm — stated explicitly rather than guessed

• The parties. The search results I retrieved did not expose the plaintiff or defendant names for 4:21-cv-00559. I attempted to pull the Unified Patents case page and to run a targeted docket search on the case number, but those tool calls did not complete (step limit reached). I do not know the party identities with confidence, and I will not guess them.
• Filing date beyond the year. Only the 2021 case-year can be read from the number.
• Outcome/status. No disposition information was returned for this case.
• Any CAFC appeal. No Federal Circuit appeal tied to this patent or this case number surfaced in my searches. I cannot rule one out, but I found none.

Other litigation — none found

Beyond the single E.D. Tex. entry above, I found no other district-court, ITC, PTAB, or foreign litigation specifically identifying U.S. 6,837,436. Searches for the patent number combined with "litigation," "lawsuit," "infringement," "complaint," and "docket" returned only patent-family, prior-art, and scholarly references — no additional case captions.

Relevant context that bears on any enforcement

• Legal status: "Expired – Lifetime," with an adjusted expiration of 2017-03-21 (Google Patents, US6837436B2). The 2021 E.D. Tex. suit therefore post-dates expiration, which (if the record is accurate) would confine any claim to past/back damages within the 35 U.S.C. § 286 six-year lookback rather than prospective injunctive relief.
• Priority family: Priority date 1996-09-05, with claimed priority from US 08/706,579 (US 5,825,002) and US 08/780,023 (US 6,084,528), and the application (US 09/990,597) filed 2001-11-21; granted 2005-01-04. Related continuations include US 7,040,541, US 7,063,263, and US 7,195,157.
• Assignee chain: Original assignee Symbol Technologies, Inc.; current assignee listed as Symbol Technologies LLC (after name changes and security-interest reassignments per the Google Patents reassignment record).

Bottom line

Known litigation = one case: Eastern District of Texas Case No. 4:21-cv-00559, reported via Unified Patents' litigation data and surfaced on the Google Patents page for US6837436B2. I could not verify the plaintiff, defendant, precise filing date, or outcome from the sources I was able to retrieve, so I am flagging those as unconfirmed rather than supplying approximate answers. If you need the parties and disposition confirmed, the next step is to pull the Unified Patents case page directly (portal.unifiedpatents.com/litigation/Texas Eastern District Court/case/4:21-cv-00559) and the PACER docket for E.D. Tex. 4:21-cv-00559.

I'll verify against the structured source and then hunt for any legacy proceedings.

Let me dig for the parallel litigation and any PTAB challenges by name.

PTAB / AIA Trial Proceedings — US 6,837,436 ("Consumer interactive shopping system")

Bottom line up front: I found no AIA trial proceedings on this patent. The structured ODP block states the default — no AIA trials on file — and independent web searching surfaced nothing contradicting it. I'm reporting that as the finding rather than manufacturing proceeding numbers.

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Proceedings overview

Total proceedings: 0. No inter partes reviews, post-grant reviews, or covered business method reviews on file for US 6,837,436 — none active, none with claims invalidated, none settled, none with institution denied. The defensive posture this creates is neither "hardened patent" nor "troll with no case" — it is "untested patent that is also expired," which is a materially better posture for a defendant than either slogan suggests: there is no IPR record to bind anyone, no § 315(e) estoppel running against any party, and the patent's term has already run out, so exposure is limited to retrospective damages within the § 286 six-year lookback.

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Why the zero-count is the correct answer here (verification trail)

• Canonical source: the ODP "PTAB proceedings on file" block returns nothing — no IPR/PGR/CBM docket entries.
• Independent search: queries targeting IPR/PGR/CBM dockets by patent number ("6,837,436" in combination with IPR2013–IPR2026, CBM20xx, PTAB, petition) returned no PTAB petition, institution decision, Final Written Decision, or termination for this patent. Results were either unrelated patents, unrelated PTAB petitions citing the '436 as background art, or patent-family documents.
• Limit on my certainty: search coverage of pre-2013 and low-visibility dockets is imperfect, and I did not query PTAB E2E docket-by-docket or the full CourtListener CAP docket. If a proceeding exists that is not indexed, the canonical ODP block you control is more authoritative than my searches. I flag that explicitly rather than asserting a negative I cannot fully prove.

Procedural door that was open and went unused: the '436 is a pre-AIA patent (priority 1996-09-05) classified in G06Q30/00, G06Q20/32, G06Q20/343, G07G1/0036 — the archetypal covered-business-method profile (financial/retail POS system, claimed technical features ancillary to a business method). CBM review was available against it from 2012-09-16 until the program sunset on 2020-09-16. Over that eight-year window, no known CBM petition was filed. That absence is a data point, not proof, but it suggests the patent was not a high-value assertion target during the CBM era.

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Related context that matters more than the PTAB record

1. The patent has expired. Google Patents' legal-status field records status "Expired - Lifetime" with adjusted expiration 2017-03-21 (the page cautions this is an assumption, not a legal conclusion; the "197 days" § 154(b) adjustment appears in the printed patent). Practical consequence: no injunctive relief, no ongoing royalty for post-2017 conduct, and damages limited to infringing acts within six years before the complaint is filed (35 U.S.C. § 286). For a demand letter received today (2026-09-27), the theoretically live damages window is roughly 2020-09-27 forward — but the patent's term ended 2017-03-21, so the actionable window is effectively zero. Verify the expiration with USPTO PatentCenter's maintenance-fee history before relying on this; maintenance-fee lapse versus term expiry lead to different conclusions about pre-2017 damages.

2. There is a district court litigation flag. The Google Patents page records a case in the U.S. District Court for the Eastern District of Texas, case 4:21-cv-00559, sourced from Unified Patents' litigation dataset (link below). That is a litigation entry, not a PTAB proceeding, and my searches did not confirm the party names or the asserted claims. Filed in 2021 — after the 2017 expiration date — which is consistent with a retrospective-damages posture. Note also that no IPR was filed in that case, which is itself unusual: defendants facing a 105-claim patent in E.D. Tex. typically file something. Treat the absence as a signal that either the case resolved early, the patent was not the primary asserted asset, or it was a low-stakes claim. I cannot confirm which.

3. Family context. The '436 is a continuation-in-part of application 09/487,923 (→ US 7,040,541), which flows from 08/780,023 (→ US 6,084,528) and 08/706,579 (→ US 5,825,002), with siblings US 7,063,263 and US 7,195,157. If your demand letter cites multiple members of this family, the PTAB picture is a family-level question, and the ODP block only speaks to the '436. No PTAB activity was surfaced for the '436 itself; I did not verify the siblings, and I will not assert a negative about them.

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Strategic summary

Claim status: 105 claims issued; none canceled, none sustained by any tribunal, all effectively untested — and all expired. Because no IPR, PGR, or CBM ever reached a Final Written Decision, there is no adjudicated claim-level scorecard. Every claim — the independent apparatus claims, the method claims, and claim 99's statistical-sampling security-check method that the Korean technology-roadmap document singled out — stands as issued, with validity presumed under § 282, and equally with zero PTAB validation. "Surviving" here is an administrative artifact of never having been challenged, not a merits outcome. The far more consequential fact about claim scope is temporal: the term ended 2017-03-21, which caps any theory at pre-expiration conduct.

Estoppel landscape: completely open. 35 U.S.C. § 315(e)(2) estoppel only attaches to a petitioner who obtained an institution decision, and estoppel under § 325(e)(2) only to a CBM/PGR petitioner who obtained institution. With zero institutions, no party is estopped from anything. A defendant today faces no estoppel map at all: every § 102 and § 103 ground drawn from patents and printed publications, plus every § 112 and § 101 ground available in district court (and in a SAS-era PTAB proceeding for a still-live claim), remains unfettered. There is likewise no PTAB claim construction (no Phillips-versus-intrinsic record) and no FWD reasoning that a court or a future petitioner is bound by — though note that a prior IPR would have helped a defendant by locking in a construction, so the absence cuts both ways.

Pattern signals: none of the usual tell-tales are present. There is no repeat petitioner (there are no petitioners), no patent-owner appeal history to the Federal Circuit arising from this patent (no FWD to appeal), no Director Review or rehearing activity, and no evidence of a defensive aggregator like Unified Patents filing on the '436 — Unified's appearance in the record here is only as the data source for the district court litigation citation, not as a petitioner. The overall pattern is of a patent that was commercialized in the 1990s–2000s (Symbol's wireless in-store shopping pilots with Albertsons and Food Lion), collected in the 2006–2011 assignee-juggling that followed Zebra's acquisition of Symbol (JPMorgan Chase collateral agent 2005, released 2014; Morgan Stanley Senior Funding collateral agent 2014, released 2015; Symbol Technologies, LLC name change 2015), and expired before the modern IPR era could reach it.

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Recommended next steps

1. Accept the zero-count, but spend 20 minutes confirming it at the source of truth. Run a party-name and patent-number search in PTAB E2E and cross-check the USPTO PatentCenter "Transactions" tab for the '436 (patent number search), which will list any PTAB proceeding in which the patent is the subject. This is cheap insurance against an unindexed petition. → https://ptacts.uspto.gov/ and https://patentcenter.uspto.gov/
2. Verify expiration and maintenance fees before anything else. The 2017-03-21 adjusted-expiration entry is the single most valuable defensive fact on this patent. Pull the fee-history in PatentCenter. If the term ended 2017-03-21, then any demand letter asserting the '436 against current conduct is facially deficient, and any damages theory is capped by § 286 at conduct in the six years before filing — which, given the expired term, yields no compensable post-issuance window after 2017-03-21.
3. Since there are no invalidating FWDs to quote, don't pretend otherwise. If opposing counsel or your client asserts that claims of the '436 "have been invalidated," correct it immediately — that is false as of 2026-09-27, and it would be sanction-bait to say so. The correct framing is: no PTAB proceeding was ever instituted against this patent; the patent expired in 2017; the claims are untested and unadjudicated.
4. Resolve the E.D. Tex. 4:21-cv-00559 entry. Get the parties, the asserted claims, and the disposition (see Unified Patents' litigation record: https://portal.unifiedpatents.com/litigation/Texas%20Eastern%20District%20Court/case/4%3A21-cv-00559). If that case was dismissed or settled in 2021–2022, it may bear on privity, license, or release defenses that no PTAB search would reveal — and those could be worth more to you than any IPR.
5. If you nonetheless want a PTAB-style invalidity record (e.g., for a co-pending case where the patent owner sues on pre-2017 conduct and you want a validity determination on the record), note that IPR of an expired patent is permitted, but the patent owner cannot amend claims and the practical benefit to a defendant is limited to a preclusive unpatentability finding — which is rarely worth the fee load when the § 286 window is already empty.

Citations and links used:

• Patent text and legal status: https://patents.google.com/patent/US6837436/en
• Litigation flag (E.D. Tex. 4:21-cv-00559, via Unified Patents): https://portal.unifiedpatents.com/litigation/Texas%20Eastern%20District%20Court/case/4%3A21-cv-00559
• PTAB document/decision portal: https://ptacts.uspto.gov/
• CAFC opinions (no '436 appeal found): https://www.courtlistener.com/?q=%226837436%22&type=o
• Claim 99 (statistical-sampling security method) text: https://uspto.report/patent/grant/6837436

Confidence statement: High confidence that no IPR/PGR/CBM is on file, based on the canonical ODP block plus negative search results. Medium confidence in the 2017-03-21 expiration date and its consequences, pending maintenance-fee verification in PatentCenter. Low confidence on anything concerning the 4:21-cv-00559 litigation, which I flagged but could not corroborate.

I'll verify the ownership record against live sources before drafting.

US 6837436 — Ownership & Assignment Reconstruction

Patent: US 6,837,436 B2, "Consumer interactive shopping system"
Appl. No. 09/990,597 · filed 2001-11-21 · granted 2005-01-04 · priority 1996-09-05 (CIP chain from US 5,825,002)
Claims: 105 · Attorney/agent of record on the face of the patent: Amin & Turocy, LLP
Google Patents legal status: Expired – Lifetime; adjusted expiration 2017-03-21

Evidence limitation, stated up front. I could not reach a live USPTO Assignment Center result set for this patent number through the tools available (assignmentcenter.uspto.gov / assignment.uspto.gov are not directly queryable here, and the indexed mirrors I could reach do not expose the reel/frame or correspondent fields for these particular events). No reel/frame numbers, execution dates, or correspondent names are asserted below unless they come from a source I actually saw. The events are taken from the Google Patents legal-events feed, which is generated from the same USPTO assignment records and is corroborated by the Zebra/Symbol corporate record. Where a field is missing I say so rather than fill it in.

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Inventors

Per the face of US 6,837,436 B2 (and the Certificate of Correction copy hosted at patents.google.com):

All five are named as assignors on the 2002 assignment to Symbol Technologies, Inc. (Google Patents event, recorded 2002-04-01), which is the ordinary-course confirmation that all five were Symbol personnel. Petrovich is also a named inventor on US 6,101,483 ("Personal shopping system portable terminal"), which US 6,837,436 itself cites as prior art — same corporate family, same program.

Unusual-pattern check — no signal. There is no evidence of inventors departing within 12 months of filing, no assignment of individual inventor rights to a third party, and no gap between filing (2001-11-21) and the inventor→company assignment (recorded 2002-04-01, i.e. ~4 months). This is the normal pattern for a well-run corporate patent program, not a precursor to a portfolio fire-sale.

Data-hygiene note (not a finding): the Certificate of Correction OCR shows variant spellings in the record — "Jorome Swartz" and "Mauro Premiuto" versus the correct "Jerome Swartz" and "Mauro Premutico." Any automated ownership-chain matching on this family must normalize these.

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Original assignee

Symbol Technologies, Inc., Holtsville, NY (Delaware corporation).

• Line of business: manufacture of bar code scanners, scan engines, handheld/mobile computers, RFID and wireless LAN infrastructure. The patent specification is written around Symbol's own commercial stack — the SPECTRUM24® frequency-hopping WLAN, the LS 4800 scanner, PDF417, and the SPECTRUM24®/IEEE 802.11 radio in a PCMCIA Type II card (col. references in the specification).
• Did it ship a product embodying the claims? Yes — Symbol was a shipping hardware manufacturer in the exact product category the claims address (portable self-scanning terminals, cradle/dispenser download, in-store RF LAN), and it was a serial enforcer of its own patents against competitors in that category. Its products are also listed on the face of the patent's prior-art field of search.
• Current status: Not operating under its own name — acquired twice, then converted.
  1. Symbol Technologies, Inc. was acquired by Motorola, Inc. (announced Sept 2006; closed Jan 2007) and folded into Motorola's Enterprise Mobility business.
  2. Motorola Solutions sold its Enterprise business to Zebra Technologies Corporation in 2014 (~$3.45B; closed late Oct 2014). This is directly corroborated in the assignment record: the 2014-10-31 security agreement lists Zebra-group obligors — Laser Band, LLC; Symbol Technologies, Inc.; Zebra Enterprise Solutions Corp.; ZIH Corp. — to Morgan Stanley Senior Funding as collateral agent, i.e. the Zebra acquisition financing.
  3. Symbol Technologies, Inc. → Symbol Technologies, LLC by change of name, recorded 2015-07-08. Today it is a wholly owned Zebra subsidiary at 1 Zebra Plaza, Holtsville, NY — this is pleaded as an admitted corporate fact in Honeywell Int'l Inc. v. Zebra Techs. Corp., W.D. Tex. No. 6:22-cv-517 (2022), ¶ 6. Zebra product documentation carries "© Symbol Technologies LLC, a subsidiary of Zebra Technologies Corporation."
• Bankruptcy: No Chapter 7/11 proceeding appears anywhere in the record; both changes of control were solvent acquisitions, not distress sales.

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Assignment timeline

All six recorded events below come from the Google Patents legal-events feed for US 6,837,436 B2. Reel/frame and Correspondent fields: NOT RETRIEVED for any entry — I will not invent them. Conveyance types are quoted as recorded.

1. Executed on or before 2002-04-01 / recorded 2002-04-01 — Reel not retrieved

   • Conveyance: ASSIGNMENT OF ASSIGNORS INTEREST (see document for details)
   • Assignor: Swartz, Jerome; Premutico, Mauro; Roslak, Thomas K.; Barkan, Edward; Petrovich, Adam
   • Assignee: Symbol Technologies, Inc., Holtsville, NY
   • Correspondent: not retrieved. The patent's printed attorney/agent-of-record is Amin & Turocy, LLP; that is a prosecution designation, not proof of who filed this recording, so I flag it as a lead only, not a finding.
   • Context: ordinary-course inventor-to-employer assignment; no third party involved.

2. Executed date not retrieved / recorded 2005-02-17 — Reel not retrieved

   • Conveyance: SECURITY INTEREST
   • Assignor: Symbol Technologies, Inc.
   • Assignee: JPMORGAN CHASE BANK, N.A., AS COLLATERAL AGENT
   • Correspondent: not retrieved.
   • Context: securitization — the patent pledged as collateral under a Symbol credit facility. Title did not move.

3. Executed date not retrieved / recorded 2014-08-28 — Reel not retrieved

   • Conveyance: RELEASE OF SECURITY INTEREST
   • Assignor: JPMorgan Chase Bank, N.A.
   • Assignee: Symbol Technologies, Inc.
   • Correspondent: not retrieved.
   • Context: release of the 2005 collateral lien (facility repaid/terminated). No title change.

4. Executed date not retrieved / recorded 2014-10-31 — Reel not retrieved

   • Conveyance: SECURITY AGREEMENT
   • Assignor: Laser Band, LLC; Symbol Technologies, Inc.; Zebra Enterprise Solutions Corp.; ZIH Corp.
   • Assignee: Morgan Stanley Senior Funding, Inc., as the Collateral Agent
   • Correspondent: not retrieved.
   • Context: securitization — the Zebra group's acquisition/credit financing, taken contemporaneously with Zebra's purchase of Motorola's Enterprise business (which is where Symbol sat). Bundle collateral, not a patent transfer.

5. Executed date not retrieved / recorded 2015-07-08 — Reel not retrieved

   • Conveyance: CHANGE OF NAME (see document for details)
   • Assignor: Symbol Technologies, Inc.
   • Assignee: Symbol Technologies, LLC
   • Correspondent: not retrieved.
   • Context: internal reorganization — corporate conversion of Symbol Technologies, Inc. into a Zebra LLC subsidiary. No change in ultimate ownership.

6. Executed date not retrieved / recorded 2015-08-17 — Reel not retrieved

   • Conveyance: RELEASE BY SECURED PARTY (see document for details)
   • Assignor: Morgan Stanley Senior Funding, Inc.
   • Assignee: Symbol Technologies, Inc. (sic — the feed shows the pre-conversion name here, an indexing/naming inconsistency worth noting)
   • Correspondent: not retrieved.
   • Context: release of the 2014 security agreement upon refinancing. No title change.

Current owner of record (Google Patents): Symbol Technologies, LLC (Zebra Technologies).
No assignment to any third-party patent-holding entity is recorded, ever.

Neighboring-record context (different patents, offered only as a corroborating observation — not a finding for '436): in the same corporate family, Symbol/Zebra's recording practice has used Zebra Technologies Corporation as correspondent — e.g. USPTO Patent Assignment 013878/0564 (Symbol Technologies, Inc., recorded 2003-03-14) and 35637/55 (to Symbol Technologies, LLC, recorded 2015-05-14, correspondent Zebra Technologies Corporation, 3 Overlook Point, Lincolnshire, IL). That is consistent with a single in-house corporate IP department running all recordings for the family; it does not establish a repeat correspondent on the '436 chain, which I could not retrieve.

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Timeline diagram

timeline
    title Ownership of US 6837436
    2001 : Application filed Nov 21
    2002 : Inventors assign to Symbol Technologies Inc
    2005 : Patent issues Jan 4
         : Security interest to JPMorgan Chase
    2007 : Symbol acquired by Motorola
    2014 : JPMorgan security interest released
         : Zebra group security agreement with Morgan Stanley
         : Motorola Enterprise unit sold to Zebra
    2015 : Name change to Symbol Technologies LLC
         : Morgan Stanley security interest released
    2017 : Adjusted patent term expires
    2021 : Texas docket linked to patent unverified

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NPE / troll-pattern signals

1. Shell-entity transfer — NOT PRESENT.
There is no transfer to any licensing-only vehicle anywhere in the chain. Every assignee is either (a) Symbol Technologies, Inc./LLC, a shipping manufacturer and now a wholly owned Zebra operating subsidiary at 1 Zebra Plaza, Holtsville, NY, pleaded as such in Honeywell v. Zebra, 6:22-cv-517 ¶ 6, or (b) a bank acting as collateral agent (JPMorgan Chase 2005-02-17; Morgan Stanley Senior Funding 2014-10-31), which by definition takes a security interest, not title. The 2015-07-08 conveyance is expressly a change of name, not an asset transfer. No "IP / Patents / Licensing / Holdings / Ventures" entity appears at any point.

2. Known asserter in the chain — NOT PRESENT.
No Acacia, Marathon Patent Group, Intellectual Ventures, IPNav, Wi-LAN, Mosaid/Conversant, Vringo, Pendrell, Innovatio, MPHJ, Lumen View, Round Rock, Document Generation Corp, or any Spangenberg-linked entity appears as assignor or assignee in any of the six recorded events. The two institutional assignees that do appear — JPMorgan Chase Bank, N.A. and Morgan Stanley Senior Funding, Inc., each "as Collateral Agent" (2005-02-17 and 2014-10-31) — are secured lenders, not assertion vehicles, and neither ever took title.

3. Repeat correspondent across the chain — UNCLEAR (unverified, not a finding).
The correspondent of record is the one field I specifically could not retrieve for any of the six events, so I cannot test for recurrence and I will not infer a name. The only attorney identity I can document on this patent is Amin & Turocy, LLP as attorney/agent of record printed on the face of the patent — a prosecution designation. The only recording correspondent I could document in the family is Zebra Technologies Corporation, 3 Overlook Point, Lincolnshire, IL (reel 35637/55, recorded 2015-05-14) — an in-house corporate IP department, the opposite of the anonymous repeat-player law firm this signal is designed to catch. To close this out, pull reel/frame + correspondent for the 2002, 2005, 2014 (×2) and 2015 (×2) recordings directly from assignmentcenter.uspto.gov.

4. Cascading transfers — NOT PRESENT.
Zero title transfers to third parties. The only events clustered within 24 months of each other are the 2014-10-31 security agreement, the 2015-07-08 change of name, and the 2015-08-17 release — all three are the mechanical paperwork of one corporate event (Zebra's October 2014 purchase of Motorola's Enterprise business and the resulting entity conversion and financing). No chained LLCs, no shared registered-agent address, no common principals among assignees.

5. Pre-litigation transfer — NOT PRESENT / NOT APPLICABLE.
No title transfer precedes any litigation involving this owner. The verifiable assertions by this owner are Symbol Technologies, Inc. v. Metrologic / ITC Inv. No. 337-TA-551 (2006-2007, mechanical scan-engine patents — not '436) and Symbol Technologies, Inc. v. Janam Technologies (D. Del., 2008). The nearest assignment-adjacent event to litigation is the 2014 collateral security agreement, which is ~7 years before the 2021 docket Google links to this patent — far outside the 6-month window, and in any event a lien rather than a conveyance.
Unverified flag: Google Patents surfaces a 2021 E.D. Tex. case 4:21-cv-00559 against this patent via Unified Patents litigation data. I could not confirm the parties, the cause of action, or whether the '436 was actually asserted rather than merely listed. Note the patent expired 2017-03-21, so any 2021 action could only reach pre-expiration conduct. Treat this docket as unconfirmed.

6. Bankruptcy fire-sale — NOT PRESENT.
No Chapter 7 or Chapter 11 proceeding appears in the ownership record for Symbol Technologies or any assignee. Both changes of control — Motorola (2007) and Zebra (2014) — were solvent, publicly announced acquisitions. Contrast the canonical fire-sale pattern (Kodak, Nortel, Polaroid), none of which is present here.

7. Privateering — NOT PRESENT.
There is no transfer, exclusive license, or shell-entity hand-off to an assertion vehicle acting for Symbol/Zebra against competitors. The patent has never left the original corporate family; it went inventors → Symbol → (same entity under Motorola, then Zebra, then a name change to LLC).

8. Defensive aggregator — NOT PRESENT.
The chain terminates at Symbol Technologies, LLC (Zebra Technologies), a shipping operating company — not RPX, AST, LOT Network, Unified Patents, or OIN. This is the inverse of neutralization: the patent simply ran its full adjusted term inside the company that has always owned it.

Additional neutral observation: the whole '436 family stayed inside the family — continuations US 7,063,263 (from 10/957,819), US 7,195,157 (11/424,370) and US 2007/0210155 (11/686,787) were all filed and prosecuted by Symbol/Zebra with no assignment out. A patent headed to a fire-sale or an NPE roll-up almost always leaves siblings behind; here every sibling stayed.

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Verdict

Operating-company assertion.

The ownership chain never leaves the original corporate family: inventors → Symbol Technologies, Inc. (recorded 2002-04-01) → the same entity under Motorola after the 2007 acquisition → the same entity under Zebra after the October 2014 acquisition, confirmed by the 2014-10-31 Zebra-group security agreement listing Symbol alongside ZIH Corp, Zebra Enterprise Solutions Corp and Laser Band LLC → change of name to Symbol Technologies, LLC (recorded 2015-07-08). The only non-Symbol assignees in the entire record are JPMorgan Chase (security interest, 2005-02-17) and Morgan Stanley Senior Funding (security agreement, 2014-10-31), both expressly as collateral agent — lenders taking liens, never title. Zero shell entities, zero known asserters, zero cascading LLC transfers, zero bankruptcy, and a current owner that is a wholly owned Zebra operating subsidiary which has itself sued competitors (ITC 337-TA-551, 2006; D. Del. v. Janam, 2008). The single open item is the correspondent field, which I could not retrieve for any recording; that is a records-access gap, not evidence of a troll pattern.

Verify at: https://assignmentcenter.uspto.gov/ (search patent number 6837436) and https://patents.google.com/patent/[US6837436B2](/patent/US6837436B2)/en (Legal Events). To close the correspondent question, request the reel/frame for the 2002-04-01, 2005-02-17, 2014-08-28, 2014-10-31, 2015-07-08 and 2015-08-17 recordings.

I'll research this patent number and its prior art citations. Let me run several targeted searches.

I have the front-page reference list. Let me verify details on the most technically relevant references.

Prior Art Analysis — U.S. Patent No. 6,837,436

Search scope note: I retrieved the bibliographic/front-page record for U.S. Pat. No. 6,837,436 (Application 09/990,597) from the patent's own front matter (via uspto.report and Google Patents). Reference dates and numbers below are transcribed literally from that record; I have not auto-corrected any identifier. Where I could not independently verify a reference's title/abstract within this session, I say so rather than supply one.

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1. The Patent at a Glance

Priority chain (family members — not §102 art to claims they support): 09/487,923 (filed 2000-01-19, issued as US 7,040,541) ← 08/866,690 (1997-05-30, abandoned) ← 08/780,023 (1996-12-20, US 6,084,528) ← 08/706,579 (1996-09-05, US 5,825,002).
Later continuations claiming priority from the '436: US 7,063,263 (from 10/957,819) and US 7,195,157 (from 11/424,370).

Critical caveat on effective dates. Because the '436 is a continuation-in-part, the 1996-09-05 priority date applies only to claims having §112 support in the 1996–2000 parents. Claim families appearing only in the 2000/2001 disclosures — e.g., the messaging agent/behavior-correlation claims (10–21, 75–84), kiosk claims (36–51), virtual-aisle remote-terminal claims (62–64), inventory-surplus discount claims (65–74), shopping-list∩inventory claims (85–98), and bag-weight security claims (99–105) — may have effective dates of 2000-01-19 or 2001-11-21. References dated 1997–2000 therefore flip from "too late" to "§102(a)/(e) prior art" depending on which claim you are attacking.

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2. The Two Reference Sets

(A) Specification-cited prior art (background / incorporated by reference)

These do not appear on the face-page "References Cited" list I retrieved, but are expressly discussed in the '436 text:

(B) Face-page "References Cited — U.S. Patent Documents" (60 references)

Listed in §3 below.

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3. Detailed Analysis of the Most Relevant References

(§102 requires every element of a claim in a single reference. My claim mapping identifies "potentially anticipates" where the reference's disclosure is coextensive with a claim; otherwise I say so.)

1. U.S. Pat. No. 4,947,028 — Gorog — issued 1990-08-07
Automated order-and-payment system permitting a customer to place orders from a remote terminal and have goods delivered/picked up. Potentially anticipates: nothing literally; highly material to §103 against claim 62 (remote terminal + merchant host + customer database) and claim 33 (delivery-method selection in out-of-store mode).

2. U.S. Pat. No. 5,227,874 — Von Kohorn — issued 1993-07-13
System for evaluating consumer responses to broadcasts, collecting response data and generating incentives. Potentially anticipates: claim 34 (message selection based on an inference engine) and claim 80 (message control value / monitoring customer response) only if the response-and-incentive loop is read onto the claims — arguable, not clean.

3. U.S. Pat. No. 5,250,789 — Johnsen — issued 1993-10-05
In-store product-information/display apparatus. Potentially anticipates: none alone; §103 against claims 36/41 (message displayed in response to a product registration).

4. U.S. Pat. No. 5,340,970 — Wolfe, Jr. et al. — issued 1994-08-23
Self-checkout security-characteristic database with supervisory override/update of stored measurable characteristics. Potentially anticipates: claim 99's weight/characteristic verification preamble only in part; better used against claims 99–105 in combination with 5,877,485.

5. U.S. Pat. No. 5,420,606 — Begum et al. — issued 1995-05-30 / U.S. Pat. No. 5,478,989 — Shepley — issued 1995-12-26 / U.S. Pat. No. 5,463,209 — Figh et al. — issued 1995-10-31
Shopping-cart-mounted display/electronic advertising and instant-checking systems. Potentially anticipates: claims 2/15/22 (device secured to a shopping cart) — the cart-mounted display element is squarely disclosed; but these references lack the host-side messaging agent that the independent claims require.

6. U.S. Pat. No. 5,640,? / U.S. Pat. No. 5,664,110 — Green et al. — issued 1997-09-02
Remote/electronic ordering system with customer-specific order data. Potentially anticipates: claim 62's remote-terminal ordering preamble and claim 9 ("product list generated by the consumer at home").

7. U.S. Pat. No. 5,761,648 — Golden et al. — issued 1998-06-02
Interactive marketing network using electronic certificates/coupons distributed to identified consumers. Potentially anticipates: claims 6 ("indications of which products … are available at a discounted rate") and the electronic-coupon aspects of claims 7C/7D disclosure; §102 candidate for the electronic-coupon dependent claims if such claims existed — the '436 does not claim couponing alone, so this is §103 material against claims 6 and 10.

8. U.S. Pat. No. 5,918,211 — Sloane — issued 1999-06-29
In-store electronic advertising delivered to a shopper-carried display, with advertisements selected/triggered in response to products the shopper scans. Potentially anticipates: claims 41 and 42 ("display of said selected message is triggered in response to the customer registering a product" / "in response to the location of the customer") and is the strongest §102/§103 candidate for claim 10 to the extent Sloane's message selection responds to scanning. Note: Sloane does not disclose real-time modification of stored shopping-behavior data, which is claim 10's distinguishing limitation.

9. U.S. Pat. No. 5,950,173 — Perkowski — issued 1999-09-07
Electronic/remote merchandising system (customer terminal, merchant host, product database, promotional presentation). Potentially anticipates: the remote-shopping preamble of claims 62–64; does not disclose the claimed "virtual aisles and virtual shelves" graphical arrangement with correlated promotional messages in the same reference.

10. U.S. Pat. No. 5,970,469 — Scroggie et al. — issued 1999-10-26; U.S. Pat. No. 6,014,634 — Scroggie et al. — issued 2000-01-11; U.S. Pat. No. 6,185,541 — Scroggie et al. — issued 2001-02-06
Purchase-history-based incentive generation and distribution (Catalina-style). Potentially anticipates: claims 10 and 75 — customer database storing shopping-behavior characteristics, message selection correlated to those characteristics. The gap is that Scroggie's behavior data is updated after the transaction, whereas claim 10 requires modification in real time as the customer registers product identification numbers.

11. U.S. Pat. No. 6,055,573 — Gardenswartz et al. — issued 2000-04-25; U.S. Pat. No. 6,298,330 — Gardenswartz et al. — issued 2001-10-02
Networked shopping aids/incentives targeted to identified customers. Potentially anticipates: claims 10, 36 (host with customer database, customer identification code, message selector correlated to customer information) and 52. Same real-time gap as Scroggie.

12. U.S. Pat. No. 6,084,528 — Beach et al. — issued 2000-07-04 (filed 1996-12-20)
"Intranet scanning terminal system": portable terminals with a machine-code reader that reads a product information address (URL) from a machine-coded file, a spread-spectrum radio, and a central controller with a spread-spectrum access point and a central database of product data including price data. This is a parent application in the '436 priority chain — it is therefore not §102 art to claims supported by it, but it is the reason many '436 claims are anticipated on their face by their own parent. Its URL/central-database disclosure maps to claims 1 (comprehensive database, central host) and 7B's bookmarking disclosure.

13. U.S. Pat. No. 6,104,483 — Petrovich et al. — issued 2000-08-08
Symbol Technologies portable-shopping art; Petrovich is a named co-inventor of the '436. Because it is commonly owned and shares an inventor, it is primarily an obviousness/§103(c) or double-patenting consideration rather than clean §102 art. (I did not independently verify its abstract this session.)

14. U.S. Pat. No. 6,123,259 — Ogasawara — issued 2000-09-26
Shopping-support system that directs a customer along a path through the store to the location of each desired product. Potentially anticipates: claims 8 and 40/48/90 ("sorting of the product list according to the layout of the shopping establishment," aisle-sorted lists) and claim 91 (information useful in locating products).

15. U.S. Pat. No. 6,155,486 — Lutz — issued 2000-12-26
Self-checkout terminal with weight-based security verification of scanned items. Potentially anticipates: the preamble and step (e) comparison of claim 99, but not the claimed bag-level net-weight sampling/staging of steps (c)–(f); combine with 5,877,485 for §103.

16. U.S. Pat. No. 6,317,722 — Jacobi et al. — issued 2001-11-13
Recommendation system selecting items based on stored user/behavior profiles. Potentially anticipates: claim 34 (inference-engine-based message selection) and claims 75–76 (behavior-category classification with database modification). Note the issue date (17Nov2001) is before the 2001-11-21 filing, but §102(e) requires its earlier filing date for full effect.

17. U.S. Pat. No. 6,330,543 — Kepecs — issued 2001-12-11
Issued after the '436 filing date (2001-11-21): available only as §102(e) art from its own effective filing date, and only against claims not entitled to the 1996 priority date.

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4. Consolidated Reference Table (Face-Page Citations)

(All 60 face-page entries accounted for; entries 1–4 and the citation numbers above correspond to the retrieved front-page order.)

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5. Conclusions

1. No single face-page reference anticipates independent claim 1. Claim 1 requires, in one system, a store/out-of-store wireless shopping device, a comprehensive database, a central host with a messaging agent in communication with third-party servers, and an intermediate consumer presentation device with a data aggregator. Oosterveen/'296 supply the issued self-scanning terminal; Beach '528 supplies wireless URL-based product-data retrieval; Sloane '211 supplies message triggering. None supplies all four. Claim 1 is a §103 combination case, not §102.

2. Claims 99–105 are the most exposed. U.S. Pat. No. 5,877,485 (Swartz; statistical sampling security for self-scanning checkout, incorporated by reference in the '436) is a genuine §102 candidate for the bag-sampling net-weight comparison of claims 99–104, and U.S. Pat. No. 6,155,486 (Lutz) covers the terminal-side weight-verification step.

3. Claims 10, 41, 42, 75, 80 are the next most exposed, via Sloane 5,918,211 (scan-triggered in-store advertising), Scroggie 5,970,469/6,014,634 and Gardenswartz 6,055,573/6,298,330 (behavior-correlated incentive generation), and Jacobi 6,317,722 (inference-based recommendation). The "modified in real time as the customer registers product identification numbers" limitation of claim 10 is the load-bearing distinction that these references appear to miss — expect that limitation to be the focus of any validity challenge.

4. The 1996 priority date is doing most of the defensive work. References issued 1997–2000 (Beach, Sloane, Perkowski, Scroggie, Gardenswartz, Golden) fall inside the one-year §102(b) window measured from the 2001-11-21 filing but outside it measured from 1996-09-05. To survive, claims 10–21, 36–51, 62–64, 65–74, 75–84, 85–98 and 99–105 need §112 support in 08/706,579, 08/780,023, 08/866,690 or 09/487,923. If they lack it, the effective date collapses to 2000-01-19 or 2001-11-21 and the whole 1997–2001 block becomes §102(a)/(e) art.

5. Two date anomalies recorded, not corrected: (a) the priority date is stated as 1996-09-05 by Google Patents and 1996-09-04 by Unified Patents; (b) the primary examiner is recorded as "St Cyr; Daniel" with attorney Amin & Turocy, LLP.

Not determined in this session: verified titles/abstracts for a minority of the older references (e.g., 5,361,871 Gupta; 5,292,882 Kornides is a typo-risk entry; I have transcribed "5,297,882 Kornides," "5,192,854 Counts," and "5,420,606 Begum" exactly as retrieved without assuming a corrected spelling). If you want, I can pull each of those individually and confirm title, abstract, and independent-claim text for a formal §102 chart.

I'll research the prior art landscape for this patent, focusing on the references cited in the patent itself and the broader field of self-scanning/wireless shopping systems.

Let me research the specific prior-art references cited on the face of the patent and in the family's search reports, since those are the strongest §103 candidates.

Obviousness Analysis — U.S. Patent 6,837,436 B2 under 35 U.S.C. § 103

Analyst's note on scope. This builds on the previously generated Patent summary and Litigation summary rather than repeating them. I use the prior art identified on the face of the patent (the "References Cited" list and the spec's own Background), the ISA/EPO search reports for this family, and references surfaced by search. Per your rule, all identifiers are reproduced literally and I do not auto-correct them — including the OCR artifacts in the certificate-of-correction front pages (e.g., "4,787,467 … Johnnie," "5,630,088 … Goreg," "5,859,414 … Sloane," "5,220,789 … Johnson"), where the printed names/numbers appear garbled. I flag each place where an identifier's reliability affects the analysis rather than silently repairing it.

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1. Legal framework applied

I apply the Graham v. John Deere framework as refined by KSR Int'l Co. v. Teleflex Inc., 550 U.S. 398 (2007): scope and content of the prior art, differences between the prior art and the claims, level of ordinary skill, and any secondary considerations. Under KSR, a combination is obvious where the elements are known, the combination is of the type suggested by the prior art, and there is a "design incentive, market pressure, or other impetus" to combine — including where the combination of familiar elements according to known methods yields predictable results. MPEP § 2143 rationales relied on below: (A) combining prior art elements according to known methods; (B) simple substitution of one known element for another; (C) use of known technique to improve similar devices in the same way; (D) applying a known technique to a known device ready for improvement; (E) "obvious to try"; (F) design incentives/market forces; (G) teaching, suggestion, or motivation in the prior art.

Important structural observation: almost every independent claim here (1, 10, 22, 33, 36, 44, 52, 57, 62, 65, 70, 75, 80, 85, 99) is a system-configuration or business-process claim whose novelty lies in which node performs which conventional function (scanner vs. cart-mounted display vs. kiosk vs. cradle vs. remote terminal vs. manufacturer's server) and which data is stored where (product profile, customer profile, "correlation data," inventory list). That is the classic fact pattern for § 103 rather than § 102, and the analysis below is organized accordingly.

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2. Threshold issue: the effective filing date is claim-specific, and this materially expands the prior art

The application (09/990,597) was filed 2001-11-21 as a CIP of 09/487,923 (filed 2000-01-19), which is a division of 08/866,690 (1997-05-30, abandoned), a CIP of 08/780,023 (1996-12-20 → US 6,084,528, Beach et al.), a CIP of 08/706,579 (1996-09-05 → US 5,825,002, Roslak/Swartz). Google Patents states the priority date as 1996-09-05.

• Claims are entitled to the 1996-09-05 date only for subject matter actually described in the 5,825,002 disclosure (under § 112 ¶1 written-description/possession as of that date).
• Subject matter that first appears in the 2000 or 2001 CIP disclosures — the FIGS. 16–21 product/customer profile databases, the correlation ("complementary / substitute / competitive alternative") tables, the intelligent messaging agent, the virtual-store GUI of claim 62, the inventory-surplus discounting methods of claims 65/70, the message "control value" of claim 80, the availability-list method of claim 85, and the net-weight audit of claim 99 — presumptively carries a 2000-01-19 or 2001-11-21 effective date.

Why this matters: it moves a large body of art into § 102(b)/§ 102(e) position. Specifically, US 6,084,528 (Beach) issued 2000-07-04, US 6,101,483 (Petrovich) issued 2000-08-08, US 5,913,210 (Call) issued 1999-06-15, US 6,029,141 (Bezos) issued 2000-02-22, Doorenbos et al. (Feb. 1997), WO 98/44462, O'Hagan 5,821,513 (1998) and the IBM TDB (June 1992) are all prior art to the CIP-added claims. I could not, from the materials retrieved, verify line-by-line § 112 support in the 1996 parents for each CIP-added limitation; this premise should be confirmed against the file wrapper before relying on it adverse to any specific claim.

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3. Level of ordinary skill (POSITA)

A person having ordinary skill in the art as of 1996–2001 in this field would have: a bachelor's degree in electrical engineering or computer science (or equivalent), plus 2–4 years' experience with retail data-collection/point-of-sale systems, including handheld optical-code readers, RF LAN infrastructure (e.g., Symbol SPECTRUM24®), in-store POS controllers (the spec names the IBM 4680/90), and client-server database programming. This is a mature, highly incremental engineering art dominated by a single assignee (Symbol). That matters under KSR: the "inventor" is not a lone artisan but the incumbent with the largest catalogue of the very components claimed.

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4. The prior art of record (evidence table)

Confirmed from retrieved text (with source):

Also relevant, surfaced in search but not prior art to the 1996/2000/2001 dates and therefore used only as evidence of the art's level: US 6,614,049 (Barkan, Symbol — home barcode scanning → coupon matching → aisle-sorted list; filed 2002-03-29), US 7,444,295 / US 2008/0243626 (Media Cart), US 7,620,475 (terminal dispenser), US 7,856,368 (Royal Ahold/Unipower) and US 2002/0147642 — the last two being a very useful roadmap of what the field already had: a database of "location of each item within the store," "UPC bar code identification number and price of each item," "number of items in stock," "manufacturer's coupons," "each user's personal purchasing habits," and "uploaded user shopping lists," plus location tracking by triangulation/biangulation.

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5. Claim-by-claim obviousness combinations

5.1 Claims 1–21 — wireless in-store marketing with an "intermediate consumer presentation device"

Proposed combination: Oosterveen '942 (or NL '296) + US 5,825,002 + US 5,250,789 (Johnsen) + Malec '952 or O'Hagan '513; optionally + Beach '528.

Element mapping for claim 1:

• wireless shopping device with scanner + product-list memory, usable at home or in-store → Oosterveen's scanner + product list; home use is the Johnsen claims 19–22 list-generation-by-scanning method and the § 102(b) home-scanning lists (US 6,533,173; Jelen '276 at the base-unit-via-WAN level).
• comprehensive database of products available in the establishment → the POS price/PLU file that Oosterveen's reader is downloaded against, and expressly the IBM 4680/90-type controller the '436 spec admits is standard.
• central host in communication with the device via an intermediate consumer presentation device → Oosterveen's dispenser is exactly that: the scanner does not talk to the store computer; it is inserted into the dispenser, which is the intermediary that reads the memory and passes it to the central processor. Adding a display and a data aggregator to that intermediary is the whole of the claim's remaining novelty, and Johnsen already puts a programmable display on the cart that does precisely the aggregation functions named: showing promotions keyed to scanned codes, showing coupons matching the shopper's products, and sorting the shopping list by store location.
• messaging agent selecting messages → Malec '952 and O'Hagan '513 (in-store computer selects promotions and downloads them to the cart display); Beach '528 (central host holds the coupon database).

Motivation to combine (MPEP 2143 (A), (C), (F)): Oosterveen's dispenser is a wired batch readout with a printer; the assignee's own SPECTRUM24® LAN was already deployed for the same terminals in the same stores (admitted in the '436 spec at ¶[00042] and in US 5,825,002). Replacing the wired download port with the already-available RF link is a simple substitution of one known element for another with predictable results (no loss of the download function, gain of real-time feedback). Once the peripheral is a display rather than a printer, sellers have an obvious economic incentive (advertising/coupon revenue, admitted in the '436 spec itself) to push messages through it — Malec and O'Hagan show the field doing exactly that years earlier.

Dependent claims 4–8 and 11–21 add: location tracking (Malec/O'Hagan zone triggers; Ogasawara's item-location database; the Ahold FAP's triangulation), discount indications (Johnsen claims 14–17), store-layout sorting and "only products offered by that establishment" (Johnsen's location-organizing program; Beach's store-layout GUI), preferred payment method and automatic charge (EP 0 681 273's paying device; WO 98/44462's automatic card transaction), home docking station (US 6,533,173 / Jelen '276 WAN base unit), remote manufacturer/distributor computer (Beach '528 host-to-third-party links), kiosk upload/download (Beach and DE 196 29 139's code-identified receptacle), inference engine (rule-based selection is a routine programming choice; Von Kohorn's response-modeling already supplies the statistical framework), and "based at least partly on chance" (a lottery mechanic — see the '436 spec's own admission that such an implementation is only constrained by law).

5.2 Claim 10 (+ 11–21) — real-time shopping-behavior database and correlated messaging

Combination: Malec '952 / O'Hagan '513 / Asthana 1994 + Von Kohorn '874 + Humble (US 4,949,256 / 4,833,308) or Vela (US 4,882,724) + Oosterveen '942 + Beach '528.

The only limitation that arguably distinguishes claim 10 over this combination is that the behavior-characteristic data is "modified in real time as the customer registers product identification numbers." That is not a technical advance; it is the inevitable consequence of putting the reader on a wireless link (Beach '528; the assignee's admitted SPECTRUM24 network) instead of Oosterveen's end-of-trip batch download. Von Kohorn and the Humble/Vela POS-history patents supply the customer-behavior database; Malec/O'Hagan supply selection-and-download of the message; Asthana supplies the in-store personalized-assistant framework. Rationale (C)+(D): using the known real-time RF technique to improve the known batch terminal in the same way (immediate targeting rather than next-trip targeting) is precisely "applying a known technique to a known device ready for improvement."

Claim 12 (location inferred from the scanned product's location record) is squarely disclosed by US 6,123,259 (Ogasawara): the central computer "accesses that item's location and assigns that particular location to be the customer's current location."

5.3 Claim 22 (+23–32) — first scanner + second cart-latched display; "correlation data"

Combination: Oosterveen/'296 (handheld scanner) + US 5,250,789 (Johnsen) (cart-mounted programmable display, scanner, promotions on scan, wireless revised promotions) + US 4,973,952 (Malec)/US 5,821,513 (O'Hagan) (networked cart display + host-selected promotions) + market-basket/complementary-item teaching (Johnsen's "complementary items"; US 5,918,211 Sloane-type purchase-incentive generation) + US 6,129,276 (Jelen) (cart-mounted portable data collection device with tethered reader).

Motivation: Johnsen already places both a scanner and a display on the cart; splitting them into a handheld reader and a cart-latched display (Jelen shows the cart mount; the detachable-scanner arrangement is expressly described in the '436 spec) is a configuration choice between two known arrangements, with the predictable benefit that the customer can scan an item at the shelf while the larger display stays with the cart. The "correlation data linking a product ID with related products" is the well-known complementary/substitute/competitive-alternative merchandising relation — the same relation the field used for "hot dogs → buns" prompts and for cross-couponing, and the same relation the '436 spec admits may be derived by mining customers' shopping behavior. No new instrumentality is required: it is a database join, i.e., routine programming on a known host (Beach '528's controller).

5.4 Claim 33 (+34–35) — delivery-method prompt only in "out of store" mode

Combination: Johnsen '789 claim 19–22 (shopping list generated at home by scanning, carried to the store on media) + US 6,533,173 / Jelen '276 (list compiled remotely and transmitted to a retailer base unit over a WAN) + the home-delivery ordering flow of the online-grocery art (Peapod; US 5,664,110 Green-type remote ordering, cited on the '436 face) + Beach '528/Oosterveen for the in-store path.

The distinction the claim draws is a conditional branch on a mode flag: "if out-of-store, ask the customer how the goods should be delivered; if in-store, do not." Given a single device admittedly usable both at home and in the aisle (the '436 spec says so in terms), suppressing a delivery prompt in the store is the kind of non-technical business-rule differentiation that a POSITA would adopt as a matter of ordinary user-interface design, with predictable results. Claim 34's "inference engine" and claim 35's "chance" selection are likewise routine.

5.5 Claims 36–43 and 44–51 (kiosk) / 52–61 (cradle)

Combination: Oosterveen '942 (dispenser with customer identification, readout station) + NL '296 + US 5,825,002 (dispenser slot codes, self-diagnostic, dumb-terminal RF) + Beach '528 (kiosks; "hot sync"; store-layout GUI) + DE 196 29 139 (receptacle identified by a code read by the device's scanner) + Malec '952 / O'Hagan '513 / Johnsen '789 (message selection & triggering) + US 6,123,259 (trigger on scan/location) + Von Kohorn / behavioral databases (claim 36's customer-correlated message).

• The kiosk as a fixed station performing the portable terminal's functions: the '436 spec itself concedes ("Kiosk 19 has many features that are common to terminal 21A"; the reconfiguration key "permits a facility to connect the portable terminal to a fixed station … as part of a kiosk"). A known device (the terminal) placed in a second known environment (a fixed, aisle-side enclosure) with no change in function is MPEP 2143 rationale (B)/(D).
• The cradle of claims 52/57 is literally Oosterveen's holder/dispenser pocket and US 6,409,086's / EP 1 031 936's docking cradle with electrical connector. Claim 53 (cradle in a kiosk) and claim 54 (kiosk on a store end cap) are placement choices.
• The triggering agent (claims 41–43, 49–51, 55–56, 60–61) is fully anticipated in kind by Malec '952 (zone trigger), O'Hagan '513 (in-zone signature → location-based content), Johnsen '789 (scan-triggered promotion), and Ogasawara (scan-inferred location), plus the '436 spec's own "time of day" trigger which is the most conventional of all messaging schedulers.

5.6 Claim 62 (+63–64) — remote terminal with "virtual aisles and virtual shelves"

Combination: Doorenbos et al. 1997 (WWW comparison-shopping agent) + US 5,913,210 (Call) / US 6,029,141 (Bezos) / US 5,897,622 (Cohen) / US 5,664,110 (Green) + the 1993–95 NPL on virtual malls and eShop cited in US 6,026,376's prior-art list + Beach '528's "GUI which simulates a store layout, i.e., aisles with items in them as they are stacked within the store."

Motivation (A)+(F): Beach '528 — a member of this very family, issued 2000-07-04 — already teaches a store-layout-simulating GUI. Extending it from the in-store terminal to a home PC over a WAN is the express purpose of that family's disclosure (and of the '436 spec's ¶[00217]). Correlating promotional messages to a logged-in customer ID is Bezos/Cohen/Doorenbos. Claim 63's 3-D representation is the 1994 "virtual reality mall" NPL; claim 64's mouse selector is a textbook GUI alternative.

5.7 Claims 65–74 — manufacturer/distributor (or store) inventory-surplus discounting transmitted to wireless shopping devices

Combination: Von Kohorn '874 (promotion evaluation/responses) + the coupon/manufacturer-rebate systems cited on the '436 face (Gorog '028/'088; Sloane '414/'211; Scroggie '469/'634; Laor '069) + Malec '952 / O'Hagan '513 / Beach '528 (host pushes revised promotions to in-store terminals) + WO 98/44462 (automatic financial transaction on the terminal).

Claim 65's method is: compute surplus → compute discount as a function of surplus → transmit to the wireless device → notify the consumer. Every step is a conventional commercial-branch-office function; the only technical step is the transmission, which Malec/O'Hagan/Beach already do. Under KSR, "market forces" and "design incentives" make the combination obvious: clearing excess inventory with price promotions is the ordinary, well-understood tool of retail, and the '436 spec's own description ("if a store determines that it is overstocked with eggs, the system may promote the eggs by offering discounts") reads as a routine application of the disclosed messaging channel. Dependent claims 66–68/71–73 (measure responsiveness, report it back, adjust the discount) map onto Von Kohorn's promotion-evaluation loop — the closed-loop marketing measurement was a known technique in 1993.

5.8 Claims 75–79 — behavior-category classification loop with real-time monitoring and database modification

Combination: Von Kohorn '874 + Humble '256/'308 or Vela '724 (POS-derived customer purchase histories) + Malec '952/O'Hagan '513 (selection and delivery of messages to in-store terminals) + Asthana 1994 (wireless personalized shopping assistant) + Oosterveen '942/'296 and Beach '528 (the wireless device and central host).

Step (a) classification into a "behavior category" and (c) associating a message with that category are standard market-segmentation and targeting operations; step (e) real-time monitoring and (f) DB modification are the closed loop Von Kohorn discloses at the broadcast level and O'Hagan's base unit discloses at the in-store level. Claim 77's two-piece handheld + cart-mounted display is the Johnsen/Jelen configuration addressed in § 5.3.

5.9 Claims 80–84 — "message control value" compared to a threshold; adjust in response to monitoring

Combination: Von Kohorn '874 (measure and evaluate consumer response to promotions) + Malec '952/O'Hagan '513 (continuously updated downloads to in-store displays) + the recognized problem of display-message overload in the same art — see the field's own literature characterizing zone-triggered cart systems as displaying promotions "non-discriminat[ingly]" so that "some users may find it bothersome or annoying" (US 2002/0147642, describing Malec and O'Hagan).

Motivation (D)+(G): the problem (consumer annoyance at excessive in-store messaging) was expressly recognized in the prior art; the solution (a counter/threshold that gates display and is adjusted by measured response — i.e., frequency capping) was a well-known control technique in direct-response advertising. Claims 81–82 (increment when the customer does not buy, decrement when he does) and 83 (threshold set by the customer's chosen message volume) are the straightforward parameterizations, and 83's "customer selects Low/Medium/High" is described in the '436 spec as a mere option. Note the claim's particular ordering ("display if the value is below the threshold") is a labeling convention — the same limitation is met by any capped-message counter; that is a § 112/indefiniteness question as much as a § 103 one.

5.10 Claims 85–98 — electronic shopping list vs. store inventory → "product availability list"

Combination: US 5,250,789 (Johnsen) + US 6,123,259 (Ogasawara) + US 6,533,173 / US 6,129,276 (Jelen) + Beach '528 (host-side product data, kiosk, store-layout GUI).

This is the claim group with the weakest non-obviousness position, because Johnsen already teaches the core: a shopping list received by the system, a database supplying the store location for each item on the list, an organizing program, and a display of the list ordered by store location. Ogasawara teaches routing the customer to list items using a merchandise database with location data. US 6,533,173 teaches compiling the list by scanning products/coupons at home and transmitting it to a retailer base unit over the WAN. What remains — intersecting the list with the store's inventory file and showing only what is in stock — is a known database operation ("product availability list comprised of products that are common to both") with a self-evident commercial purpose. Claims 86 and 90–93 (kiosk coupling, store-layout ordering, locational help, printing) are Johnsen + Beach + Ogasawara verbatim in substance; claims 94–98 (reader, indication on reading a listed item, list generated by scanning an advertisement, cart-mounted display) are Johnsen's claims 19–21 + Jelen.

5.11 Claims 99–105 — net-weight audit excluding clerk-rescanned items

Combination: the weight-verification checkout art on the '436 face — US 4,373,133 (Clyne), US 4,779,706 (Mergenthaler), US 4,787,467 (Johnson), US 4,792,018 (Humble) — + Oosterveen '942 / NL '296 (self-scanning with "occasional audits") + WO 98/44462 (cart-weight and lift-weight comparison against the scanned total, alarm/gate) + NL 1004940 C2 (self-scanning checkout with weight-discrepancy check and permitted margins, auto-adding unknown item weights) + US 5,825,002's statistical security framework (incorporating US 5,877,485 and 6,092,725).

Claim 99 recites: sample items rescanned by a clerk; determine weights of the list items not rescanned; determine each bag's net weight (bag weight less the rescanned items); compare; disallow if "the net weight … could not be attained." The first three steps are the classic scale-verification integrity check applied to a self-scanned order; WO 98/44462 supplies the "compare the measured weight to the weight implied by the scanned list, and refuse the transaction if it doesn't correlate" teaching, including the gate/payment consequence; NL 1004940 supplies the margin-of-error and the auto-addition of unknown weights. The subtraction of the sampled items is the only arguably distinctive step, and it is dictated by the sampling method: if you have removed/weighed some items, you must exclude them from the expected total or the comparison is corrupted. That is a mathematical expedient with a predictable result, not an inventive contribution. Claim 103's "determine probability" is a routine statistical computation, and the '436 spec's own worked example (bags a, b, c = 8 / 6.5 / 4.8 lbs.) is presented as arithmetic.

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6. Cross-cutting motivation to combine

Four rationales recur and, taken together, would support a § 103 rejection across essentially every independent claim:

1. The same field, the same problem, the same actors. Oosterveen, NL '296, US 5,825,002, US 6,084,528 and US 6,101,483 are the same subject matter, often the same assignee and same inventors, addressing the same problem (self-scanning shrinkage, customer convenience, and monetizing the terminal). Under KSR, "if a technique has been used to improve one device, and a person of ordinary skill in the art would recognize that it would improve similar devices in the same way, using the technique is obvious."
2. Known network, known peripherals. The '436 spec admits the RF LAN, the handheld reader, the POS controller, the coupon database, the kiosk and the cradle were all commercially available before the claimed filing. Adding functions to them is a predictable use of known technology, warranting little weight for the specific placement of each function (which node holds the database, which node displays).
3. Direct commercial incentive. The patent itself frames the invention's economics — manufacturer/coupon-vendor funding (spec ¶[00017]) — which supplies exactly the "market pressure" KSR requires. The prior art (Malec, O'Hagan, Johnsen, Von Kohorn) was already monetizing in-store promotion delivery.
4. Prosecution reality. US 6,084,528 appears on the '436 face as an Examiner citation and US 6,101,483 as an Applicant citation, i.e., the family's own earlier disclosures were before the examiner. I did not retrieve the file wrapper or the Certificate of Correction's substantive changes, so I cannot say which rejections were made or how they were overcome — that record, not the issued face, determines whether these combinations were already considered and rebutted.

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7. Secondary considerations and the strongest counterarguments

• Commercial success / long-felt need (Symbol Personal Shopping System). The nexus is weak: the commercial embodiment predates the claimed CIP subject matter and practises the 1996 parents. Nokia-tyle arguments that the success derives from the claimed messaging-agent/database features would need proof of nexus.
• Copying / industry praise — none identified.
• Possible genuine non-obviousness candidates (i.e., where I would expect the strongest § 103 defense): (i) claim 99's specific net-weight calculation excluding clerk-rescanned items combined with bag-by-bag (rather than cart-total) comparison; (ii) claim 80's specific control-value/threshold/adjust formulation — but this is likely to fail on § 112 grounds (the claim does not specify how the value is calculated); (iii) claim 33's mode-differentiated delivery prompt, which a patentee could argue is not a technical feature at all (cutting toward § 101 trouble rather than patentability); and (iv) claim 62's "promotional messages [on] the virtual aisles" as a display metaphor.
• Teaching away: I found none. WO 98/44462, Malec, O'Hagan and Johnsen all point toward wireless in-store terminals with messaging; the Ahold FAP literature criticizes Malec/O'Hagan only for lack of personalization, which is an invitation to improve, not a teaching away.
• Practical note from the prior sections: the patent is Expired – Lifetime (adjusted expiration 2017-03-21), and the only litigation of record is E.D. Tex. 4:21-cv-00559, filed 2021 — i.e., post-expiration. Invalidity therefore has value only defensively, against back damages within the § 286 window.

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8. Bottom line

1. On the record assembled, a prima facie § 103 case exists against every independent claim, most strongly against claims 85–98 (Johnsen '789 + Ogasawara '259 + Jelen '276/6,533,173), 62–64 (Doorenbos 1997 + Bezos '141/Call '210 + Beach '528's store-layout GUI), 22–32 (Johnsen '789 + Malec '952/O'Hagan '513 + Jelen '276), and 99–105 (Clyne/Mergenthaler/Johnson/Humble weight verification + WO 98/44462 + NL '296 audit), and somewhat less forcibly against claims 1 (because of the "central host … via an intermediate consumer presentation device" chain) and 80 (because of the "control value" vocabulary).
2. The decisive variable is the effective filing date per claim. If the CIP-added subject matter is limited to its 2000-01-19 / 2001-11-21 dates, the art set expands dramatically (US 6,084,528, US 6,101,483, US 6,123,259, US 6,029,141, WO 98/44462, Asthana 1994, Doorenbos 1997) and the analysis above is essentially complete. If the patentee successfully claims 1996-09-05 for a given claim, US 6,084,528 and US 6,101,483 drop out as § 102(b) art (they remain § 102(e)/family references) and the analysis must be re-run on the 1996 art alone — the Oosterveen/NL '296/Johnsen/Malec/O'Hagan/Von Kohorn core still supports the rejection for the system-configuration claims, but with less margin.
3. Explicit uncertainties: (a) I did not read the Certificate of Correction; the operative claim text may differ from the transcript I analyzed. (b) I did not retrieve the file wrapper for 09/990,597, so I cannot confirm which of these combinations the examiner already considered. (c) Several front-page reference identifiers appear garbled in the scanned text ("Johnnie," "Goreg," "Flipfront," "Strabbe," "Serogate," "Tabbott"); I have not corrected them and they should be verified against the printed grant. (d) I did not verify the content of the IBM TDB (1992), Asthana (1994), Call '210, Cohen '622, Bezos '141, Green '110, Clyne '133, Mergenthaler '706, Johnson '467, or NL 1004940 C2 beyond the citation-level information quoted above; where I have relied on their titles or on third-party characterizations, I have said so rather than asserting disclosure content.

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