US 5334821

I'll search for the specific patent number and any related litigation.

US 5,334,821 — Summary

Important caveat on identifiers: A search for "5334821" also surfaces JP 5334821 B2 (a 2013 Japanese patent to TOWA Corporation for a resin-sealing apparatus) and a Japanese reference "5334821" cited in US 6,324,032. These are unrelated to the U.S. patent you asked about. Per your instruction, I have not conflated them. Likewise, all statements below relate strictly to US 5,334,821, not to any similar number.

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Bibliographic data

Source: https://patents.google.com/patent/US5334821/en

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Abstract (verbatim)

"A point of sale terminal is disclosed that provides all of the usual point of sale terminal functions, but that is entirely field portable. Data pertinent to each purchase can be input to the terminal via a keyboard assembly, a touch-screen display or a signature-capture screen assembly, or via an antenna and radio link from an associated bar code scanner. Data may be communicated at any time to a remote host computer, also via a separate antenna and radio link. The communication links with the host computer and the bar code scanner operate independently and simultaneously, using mutually compatible modulation schemes such as a spread spectrum scheme for the host computer link and a narrowband or spread spectrum scheme for the bar code scanner link. The terminal thereby functions as a portable repeater or node in a data communications network."

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The claims (10 total)

Only Claim 1 is independent. Claims 2–4, 5–6, 7–8, 9, and 10 all depend, directly or indirectly, from Claim 1. Plain-language overview of the independent claim and its dependents:

Claim 1 (independent) — the core combination. A portable point-of-sale terminal made of five elements:

1. a hand-carryable housing with a front face;
2. a keyboard and a display mounted on that front face;
3. a power source inside the housing;
4. a first electromagnetic transceiver inside the housing for two-way over-the-air data to/from a host computer; and
5. a second electromagnetic transceiver inside the housing for two-way over-the-air data to/from a remote input/output device (e.g., a bar code scanner).

In plain terms: a luggable POS terminal with two built-in radios — one talking to the store host, one talking to a peripheral — rather than a conventional tethered, counter-mounted register.

Dependent claims (in plain language):

• Claim 2 (→1): Specifies the modulation scheme — the first link uses spread spectrum on a first carrier; the second uses a narrowband carrier placed at a null in the power spectrum of the spread-spectrum signal, so the two links coexist without interference (illustrated in FIG. 8).
• Claim 3 (→1): The two transceivers must operate simultaneously on non-interfering frequencies.
• Claim 4 (→3): One or both links may use spread spectrum.
• Claim 5 (→1): The front-face housing has a recess, and the terminal includes multiple interchangeable keyboards, each sized to be removably seated in that recess.
• Claim 6 (→5): The power source is one or more removable batteries, and a keyboard can be installed/removed only when the batteries are removed (a safety interlock preventing live keyboard swaps — described in the spec as minimizing electrical-hazard exposure).
• Claim 7 (→1): Adds an internal printer that prints on a paper strip and discharges it from the housing, plus a signature-capture screen on the front face that senses handwritten information and generates corresponding data.
• Claim 8 (→7): The printer is positioned adjacent to the screen so that the discharged paper overlays the screen — the customer signs the receipt directly on top of the capture screen (which also spreads pen pressure and protects the screen).
• Claim 9 (→1): The display is a touch-sensitive type that senses an operator's manual selection of information.
• Claim 10 (→1): Adds a credit-card slot in the front face and magnetic-stripe reader circuitry inside the housing for reading a card swiped along that slot.

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Litigation history found

• Symbol Technologies, Inc. v. Janam Technologies LLC, U.S. District Court for the District of Delaware, No. 1:08-cv-00340-JJF (filed June 9, 2008; patent report filed June 10, 2008). The suit asserted the '821 patent together with US 5,835,366 and US 6,714,969.
• Memorandum Opinion of March 31, 2009, reported at 605 F. Supp. 2d 618 (D. Del. 2009), adopted-in-part a magistrate judge's Report and Recommendation and tentatively construed disputed terms for purposes of a preliminary-injunction motion. Relevant constructions for the '821 patent:
  • "a portable point of sale terminal" (Claim 9) = "a portable computer terminal that is capable of handling a sales transaction"
  • "data" (Claim 9) = "information associated with a sales transaction"
  • "remote input-output device" (Claim 9) = "a remote device through which information associated with a sales transaction is input or output"
  • "host computer" (Claim 9) = "a remotely located computer which provides information associated with a sales transaction to the portable point of sale terminal and possesses information associated with a sales transaction from the portable point of sale terminal"
  • (The court overruled the recommendation as to "power" in Claim 7 of the separate '366 patent, construing it as "the rate at which energy is transferred, calculated by multiplying electric current times voltage.")
  • Source: http://g.casetext.com/case/symbol-technologies-5
• A Google Patents "litigation" link points to the same Delaware case docket: https://portal.unifiedpatents.com/litigation/Delaware%20District%20Court/case/1%3A08-cv-00340

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CAFC 2026 docket search — result

I found no CAFC (Federal Circuit) 2026 docket activity involving US 5,334,821. My searches for the patent number in connection with 2026 Federal Circuit filings returned only (a) the unrelated Japanese patent JP 5334821 B2 and (b) an unrelated Federal Circuit Rule 40(c) petition in a treadmill case (Woodway/LifeCORE Fitness).

This is expected: the '821 patent's term expired July 16, 2012, and its recorded assertion activity was the 2008–2009 Delaware action against Janam. I cannot rule out a low-profile 2026 filing (e.g., an appeal in a long-running dispute or a petition), but no such docket appeared in my searches, and I have no authoritative USPTO PatentCenter or CAFC docket confirmation beyond the sources above.

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Points of uncertainty (stated explicitly rather than guessed)

• I did not retrieve a live USPTO PatentCenter/Patent Assignment record directly; the bibliographic and assignment data above come from Google Patents and the Delaware filing reports. Inventor names, dates, and the Telxon→Symbol chain are consistent across sources, but the "current assignee" field is expressly noted by Google as an assumption, not a legal conclusion.
• The status of the 2008 Janam litigation (final outcome, settlement, or appeal) is not established by the sources available to me.
• No CAFC 2026 docket for this patent was located; treat any claim of 2026 appellate activity as unverified.

I'll research litigation involving US 5,334,821 specifically, being careful to exclude unrelated patents with similar numbers.

Let me dig deeper into the Janam case and look for any other assertions of this patent.

Let me check for any other cases asserting this patent, and verify the current litigation database entries.

Litigation involving US 5,334,821

Identifier discipline: The following relates only to U.S. Patent No. 5,334,821 ("the '821 patent"), Portable point of sale terminal, Telxon Corp., filed July 16, 1992, issued August 2, 1994. It is not the unrelated Japanese patent JP 5334821 B2 (TOWA Corporation, resin-sealing apparatus, issued 2013), nor the unrelated Florida FEI number "47-5334821" (Keys Dragon Marathon, LLC), both of which surface in keyword searches for "5334821."

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Known litigation: one case

Symbol Technologies, Inc. v. Janam Technologies LLC

Sources: https://portal.unifiedpatents.com/litigation/Delaware%20District%20Court/case/1%253A08-cv-00340 ; http://www.advfn.com/stock-market/NYSE/MOT/stock-news/45565718/motorola-solutions-and-janam-technologies-resolve ; https://www.ded.uscourts.gov/opinion/symbol-technologies-inc-v-janam-technologies-llc-0

Substantive rulings in that case (relevant to the '821 patent)

1. Dec. 1, 2008 — Magistrate Judge Stark's Markman/claim-construction recommendation and Report and Recommendation (D.I. 133). Symbol asserted Claim 9 of the '821 patent, which depends from Claim 1. The parties agreed the Claim 1 preamble ("A portable point of sale terminal comprising") is a limitation.
2. Mar. 31, 2009 — Memorandum Opinion and Order, 605 F. Supp. 2d 618 (D. Del. 2009) (Judge Farnan). Adopted-in-part / overruled-in-part the R&R, tentatively construing the '821 terms for purposes of the preliminary-injunction motion only:
   • "a portable point of sale terminal" (Claim 9) = "a portable computer terminal that is capable of handling a sales transaction" (rejecting Janam's construction that it must include a printer);
   • "electromagnetic transceiver" = "electromagnetic transceiver" (no construction; neither party objected);
   • "data" = "information associated with a sales transaction";
   • "remote input-output device" = "a remote device through which information associated with a sales transaction is input or output";
   • "host computer" = "a remotely located computer which provides information associated with a sales transaction to the portable point of sale terminal and possesses information associated with a sales transaction from the portable point of sale terminal."
   • The court overruled the R&R on "power" in Claim 7 of the separate '366 patent, construing it as "the rate at which energy is transferred, calculated by multiplying electric current times voltage."
3. Preliminary injunction — DENIED. The court found Symbol showed a likelihood of success on literal infringement of the '821 patent (the XM-60 was reasonably likely to contain both required electromagnetic transceivers), but could not show a likelihood of success as to the '366 patent because Janam raised substantial invalidity questions (Sandstedt reference, alone or combined with Kurland or Gombrich). No presumption of irreparable harm post-eBay, price-erosion harm quantifiable in damages, and the balance of hardships favored Janam (a small startup whose survival was at stake). Public interest alone did not tip the balance.
4. Jul. 2010 — 729 F. Supp. 2d 646 (D. Del. 2010), 2010 WL 2898292 — denied Janam's motion to preclude Symbol from relying on Symbol's profits/lost-profits evidence and to strike portions of the Strickland Declaration and Symbol's reply brief.
5. Dec. 8, 2010 — settlement; dismissal.

Sources: http://g.casetext.com/case/symbol-technologies-5 ; https://ipmall.law.unh.edu/sites/default/files/hosted_resources/Markman/pdfFiles/2009.03.31_SYMBOL_TECHNOLOGIES_INC_v._JANAM_TECHNOLOGIES.pdf ; https://www.courtlistener.com/opinion/[2468152](/patent/2468152)/symbol-technologies-inc-v-janam-technologies-llc/

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No other litigation found; no appellate activity found

• The only litigation identified as asserting US 5,334,821 is the Delaware action above. Google Patents' litigation links for this patent both point to that same docket (Unified Patents case list entry 1:08-cv-00340).
• No CAFC/Federal Circuit appeal involving the '821 patent was found. This is consistent with the case terminating by settlement with dismissal (no appealable judgment on the '821 patent), and with the patent's term expiring July 16, 2012.
• No PTAB (IPR/PGR/CBM) proceeding directed at the '821 patent was found.
• No other plaintiff (e.g., a later Symbol Technologies LLC or Motorola Solutions assertion) was found asserting the '821 patent against any other defendant.

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Explicit uncertainties and caveats

1. Date inconsistency in the prompt. The task states "Current Date: April 26, 2026," while the session metadata gives today's date as 2026-10-01. I flag this rather than silently reconcile it; it does not affect the historical findings below.
2. Step limit reached. I was cut off mid-research (further queries to PACER/RECAP, Unified Patents' case list, and USPTO PatentCenter for later-recorded litigation could not be completed). My "no other litigation" conclusion rests on the searches actually run — it is a negative finding from available sources, not a certified docket check.
3. Docket vs. reporting. The Delaware docket detail above is drawn from the Unified Patents docket mirror, the D. Del. court website opinions, CourtListener/RECAP, Casetext, and the court's own published opinions. I did not independently retrieve the full PACER docket, so procedural details (exact dismissal date, D.I. numbers after the 2010 opinion) are not fully verified.
4. Source-label discrepancy (flagged, not corrected). One secondary summary (Studicata) labels Symbol v. Janam as "United States Court of Appeals, Third Circuit (2010)." That appears to be a mislabeling — the decisions are District of Delaware (Judge Farnan) and the 2010 decision is a district-court opinion reported at 729 F. Supp. 2d 646 (D. Del. 2010). I report the discrepancy rather than silently "fix" the source.
5. Confidential terms. The settlement amount and royalty rate are undisclosed; the December 2010 press release is the only public description of the outcome.
6. Consistency with the prior section. This is consistent with the earlier "Patent summary" section, which also identified the 2008–2009 Delaware action and the March 31, 2009 construction order at 605 F. Supp. 2d 618. The one thing it adds is the case's resolution: the December 8, 2010 settlement/license that ended the litigation — previously listed as an open item ("final outcome ... not established").

I'll verify the "no PTAB activity" baseline from the ODP block against live sources before writing the section.

Let me run targeted checks on the litigation parties, the family patents, and docket aggregators.

Let me do a final confirmation search targeting the PTAB E2E docket and any CBM filings (the patent carries a G06Q20 classification).

One verification search on a timing point that matters for the analysis.

PTAB Proceedings — US 5,334,821 ("Portable point of sale terminal")

Proceedings overview

Total AIA trial proceedings on file: 0. Zero inter partes reviews, zero post-grant reviews, zero covered business method reviews, zero derivations — no institution decisions to report, no final written decisions, no settlements, no Federal Circuit appeals from the Board. The USPTO Open Data Portal structured block in this prompt returns an empty set, and my independent web searches (patent number, patent number + "IPR," patent number + "CBM," litigation-party-targeted searches on Janam and Telxon/Symbol, and searches against the two divisional family members US 5,408,077 and US 5,408,078) surfaced no petition, no proceeding number, and no PTAB decision paper.

The bottom-line defensive posture is therefore unusual and needs to be stated carefully: the '821 patent has never been tested at the Board — not because it is "hardened," but because it expired before it could be. The patent's term ran out on 2012-07-16, and AIA trial practice did not exist to be used against it: IPR, PGR, and CBM petitions were only available for filings on or after 2012-09-16. The realistic IPR/CBM window on this patent was a matter of months, and no one used it. A defendant today is not facing a hardened patent that survived PTAB attack; it is facing an expired patent whose validity was litigated only once, in a 2008–2009 preliminary-injunction posture in the District of Delaware, and never reduced to a final merits judgment that I can verify.

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Per-proceeding entries

There are no proceedings to report, so there are no ### {PROCEEDING_NUMBER} entries. Rather than pad the record, here is what the null result actually rests on.

Negative findings and how they were reached

• ODP structured data (canonical source): no AIA trial proceedings for US 5,334,821 as of the most recent ingest.
• Independent web verification: searches combining the patent number with "inter partes review," "PTAB," "CBM," and "covered business method" returned only unrelated matter — the similarly numbered and wholly unrelated JP 5334821 B2 (TOWA, resin sealing) and an unrelated accounting figure. No petition, institution decision, FWD, or Board paper for US 5,334,821 appeared.
• Party-targeted verification: the only assertion activity on record is Symbol Technologies, Inc. v. Janam Technologies LLC, D. Del. No. 1:08-cv-00340-JJF, filed 2008-06-09. A search built around Janam, Symbol, and the '821 patent returned district court Markman and preliminary-injunction papers — no PTAB filings by Janam (or anyone else) against the '821 patent.
• Family check: I also searched the two divisional continuations, US 5,408,077 and US 5,408,078, for PTAB activity. Nothing surfaced.

Why the window was so narrow. Janam was served in mid-2008, four years before any AIA trial was available. By the time IPR and CBM became available on 2012-09-16, the patent had already expired (2012-07-16). Three practical consequences follow:

1. No § 315(b) trap for Janam. Board practice in the AIA's early months (reflected in Macauto U.S.A. v. BOS GmbH & KG, IPR2012-00004) treated a complaint served before the 2012-09-16 effective date as not triggering the one-year bar, because no IPR existed for the accused infringer to file. So Janam was not time-barred from filing after 2012-09-16 — it simply did not, or the dispute had already ended. I cannot verify which from the sources available to me.
2. CBM was theoretically available but would have been a poor fit. The '821 patent carries G06Q 20/34 and G06Q 20/343 classifications (payment architectures using cards), which invites a "financial product or service" theory under AIA § 18(d)(1). But the claims are directed to a portable terminal with two radios, a swappable keyboard, and a signature-capture screen — hardware-centric subject matter that a petitioner would have to argue is not a "technological invention" under 37 C.F.R. § 42.301(b). And CBM required the petitioner to have been sued for or charged with infringement; post-expiry, that standing hook was gone. The CBM program sunset on 2020-09-16 regardless.
3. Post-expiry economics killed the incentive. A validity challenge to an expired patent does not stop ongoing infringement — it only limits past damages. Once the 2012-07-16 expiry passed, the rational move for an accused party was to argue non-infringement and damages scope in district court, not to spend IPR fees attacking claims that could not support future royalties.

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Strategic summary

Claim status: all ten claims are UNTESTED at the Board. Nothing is canceled, nothing is sustained. There is no estoppel-producing FWD, which cuts both ways: the patent owner cannot point to a PTAB win to bolster the claims, and a defendant cannot point to a PTAB loss to kill them. For a defendant, this means the entire § 102/§ 103 playbook is unburdened by § 315(e)(2) estoppel — there is no prior petition, no privy, no real party in interest whose earlier IPR would bar a ground. The estoppel landscape section of a normal PTAB report is simply empty here.

The validity record that does exist is district court, and it is thin and non-final. In Symbol Technologies, Inc. v. Janam Technologies LLC, 605 F. Supp. 2d 618 (D. Del. 2009) (opinion dated 2009-03-31, D.I. 207/208), the court tentatively construed the '821 claim terms solely "for purposes of deciding Plaintiff's Motion for Preliminary Injunction" — expressly provisional, not a final Markman. Those constructions are nonetheless the most useful thing a defendant has, because they are narrow:

• "a portable point of sale terminal" (claim 9) = "a portable computer terminal that is capable of handling a sales transaction"
• "data" = "information associated with a sales transaction"
• "remote input-output device" = "a remote device through which information associated with a sales transaction is input or output"
• "host computer" = "a remotely located computer which provides information associated with a sales transaction to the portable point of sale terminal and possesses information associated with a sales transaction from the portable point of sale terminal"
• "electromagnetic transceiver" was given its plain meaning (no construction adopted; not objected to)

Source: https://www.courtlistener.com/opinion/[2468152](/patent/2468152)/symbol-technologies-inc-v-janam-technologies-llc/ and https://www.ded.uscourts.gov/sites/ded/files/opinions/08-340_1.pdf

The closest prior art ever actually litigated against the '821 claims is on the record and reusable. Janam's invalidity case, as recited in the PI briefing, was that US 4,569,421 to Sandstedt anticipates claim 9, or alternatively that Sandstedt in view of US 4,547,851 to Kurland or Sandstedt in view of US 4,916,441 to Gombrich renders claim 9 obvious (the touch-screen limitation of claim 9 being the point supplied by Kurland or Gombrich). That is a complete, expert-supported § 102/§ 103 theory for the claim that matters most — claim 9 depends from independent claim 1, so attacking claim 9 pulls in the full claim-1 combination. I have not verified how the district court resolved that invalidity prong, and I will not assert an outcome I did not find. Treat it as a starting brief, not a result.

Pattern signals: none of the usual ones are present. No serial petitioner (single district court defendant, no PTAB filings). No defensive aggregator — Unified Patents is not in the chain; the Unified link in the Google Patents record is a litigation-data link to the docket, not an IPR filing. The patent owner (Telxon → Symbol Technologies, recorded 2002-04-08) never had occasion to defend a PTAB appeal and never filed one. The 2008 action against Janam is the only assertion I found.

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Recommended next steps

If you are a defendant being asserted today against US 5,334,821:

1. Check the limitations date first; it is likely dispositive of everything except past damages. The patent expired 2012-07-16 (Google Patents "anticipated expiration," legal status "Expired – Lifetime"). Any § 271 infringement theory is necessarily backward-looking, bounded by the 35 U.S.C. § 286 six-year damages lookback — which, as of today (2026-10-01), reaches back only to 2020-10-01. The entire post-expiry period from 2012-07-16 to 2020-09-30 is outside the recoverable window. If the demand letter cites claim 1 as an ongoing royalty trigger, the last six years of the patent's life generate no damages at all. That is the strongest single fact in your favor and it is not a PTAB fact — it is a calendar fact.
2. There is no FWD to link to, because there is no PTAB proceeding. I want to be explicit so you do not go looking: I found no institution decision, no final written decision, no termination, and no Federal Circuit appeal touching this patent at the Board. If anyone hands you an IPR number for the '821 patent, it is fabricated — the only similarly numbered artifact in circulation is the unrelated JP 5334821 B2, and conflating the two is an error.
3. Do not file an IPR now; the vehicle is unavailable. The patent is expired, so the practical purpose of an IPR (stopping ongoing infringement) is gone, and you would be challenging claims that can support only historic damages. Attack validity in the district court or in a § 282 posture, using the Sandstedt / Kurland / Gombrich art Janam already put in front of Judge Farnan, plus US 4,947,028 (Arbor International) and US 5,189,287 (Parienti), the two references cited on the face of the patent, and the family references listed in the "Family Cites Families" record — notably US 5,107,100 (Symbol, "Portable scanner with on-board keyboard, display, transceiver and printer") and US 5,110,226 (Norand, battery-operated data entry terminal with printer attachment), both of which sit very close to the claim-1/claim-7 combination and were not before the Delaware court as far as I can tell.
4. Fight claim construction, not validity, on the "portable point of sale terminal" limitation. The Delaware court's tentative construction requires the terminal be "capable of handling a sales transaction." Janam lost on that point at the PI stage in part because its expert relied on the wrong construction, and because Janam's own NRF 2008 brochures promoted the accused XM-60 alongside point-of-sale software. If your accused product has no transaction-handling capability, build the non-infringement record on that now, before marketing materials are used against you.
5. Set expectations about this report's limits. The absence of PTAB activity is a verified null result from the canonical ODP source plus independent searching; it is not proof that no low-profile petition was ever filed and terminated at the preliminary-response stage decades ago and fell out of every index. I found nothing, and I have said so plainly rather than manufacturing a proceeding. If you need a belt-and-suspenders confirmation, pull the patent's complete file history and transaction history directly from USPTO PatentCenter / PTAB E2E (https://ptacts.uspto.gov/) and the Assignment record, rather than relying on aggregators.

I'll research the assignment record for US 5,334,821 before drafting. Let me run several searches.

Let me look for the recorded assignment details, including reel/frame and correspondents.

Ownership Reconstruction — US 5,334,821 ("Portable point of sale terminal")

Source limitation — read first. I attempted to pull live records from the USPTO Assignment Center (https://assignmentcenter.uspto.gov/) and its legacy mirror (https://assignment.uspto.gov/patent/index.html). Those endpoints did not return data to my search tooling, so I could not retrieve reel/frame numbers or the "correspondent of record" fields that this task specifically asks for. Everything below is reconstructed from the USPTO-derived legal-events record surfaced on Google Patents (https://patents.google.com/patent/US5334821/en#legalEvents), cross-checked against SEC/press coverage of the Telxon–Symbol transaction and the Delaware litigation docket. I have left reel/frame and correspondent cells marked "not retrieved" rather than inventing them. A follow-up with direct Assignment Center access is needed to close those gaps (see "Open data gaps" at the end).

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Inventors

Pattern note: All five inventors assigned to the same original assignee (Telxon) by the same instrument executed on the filing date — the ordinary employee-invention assignment, not a red flag. I found no evidence of the "all inventors depart within 12 months" pattern, but I also could not independently verify any inventor's departure date; treat that sub-question as unclear. There is no inventor continuity into the divisional filings (US 5,408,077 / US 5,408,078) that is inconsistent with ordinary practice.

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Original assignee

Telxon Corporation — named on the issued patent, a Cincinnati/Ohio-rooted maker of handheld computers, bar-code scanners, and wireless (RF) data-collection terminals. Telxon was a direct competitor to Symbol Technologies in the handheld/mobile-computing and wireless-LAN market and shipped commercial product in this space (the patent's own enablement of a radio-linked handheld terminal aligns with Telxon's product line; Telxon's Aironet division designed and manufactured the radios). Note the market-defining fact reported in the Symbol/Telxon history: Telxon championed direct-sequence spread spectrum at 2.4 GHz while Symbol chose frequency hopping — the '821 patent's spread-spectrum host link and narrowband peripheral link (Claim 2, FIG. 8) reflect that technology direction.

Current status: Telxon no longer exists as an independent entity. It fought a hostile Symbol takeover bid (rejected June 1998 at $668M), suffered a revenue-restatement and SEC accounting investigation plus securities class actions (filed 1998), and was ultimately acquired by Symbol Technologies via a stock swap completed November/December 2000 ($465M including debt, at roughly half the original offer price). Portions of Telxon were consolidated and its Houston plants closed. So: acquired and dissolved into Symbol — not operating independently.

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Assignment timeline

Chronological, per the Google Patents legal-events table (which mirrors USPTO assignment records). Format caveat: this source does not expose reel/frame or correspondent, so those are marked accordingly.

• 1992-07-16 (executed) / recorded 1992-07-16 — Reel/frame not retrieved

  • Conveyance: Assignment (assignment of inventors' interest)
  • Assignor: ANDERSON, FRED J.; CAMPO, JAMES A.; EMBREE, DONALD M.; HOFSTETTER, CHARLES J.; SLOAN, DONALD I.
  • Assignee: TELXON CORPORATION
  • Correspondent: not retrieved
  • Context: Original employee-invention assignment; the founding ownership record.

• 1994-05-20 — Reel/frame not retrieved

  • Conveyance: Security Agreement / Security Interest ("SEE DOCUMENT FOR DETAILS")
  • Assignor: TELXON CORPORATION
  • Assignee: THE BANK OF NEW YORK COMMERCIAL CORPORATION, AS AGENT
  • Correspondent: not retrieved
  • Context: Securitization — collateral lien, not an ownership transfer.

• 1996-05-07 — Reel/frame not retrieved

  • Conveyance: Release by Secured Party
  • Assignor: THE BANK OF NEW YORK COMMERCIAL CORPORATION, AS AGENT (by Daniel J. Murray, VP)
  • Assignee: TELXON CORPORATION
  • Correspondent: not retrieved
  • Context: Release of the above lien; ownership stays with Telxon.

• 1999-03-30 — Reel/frame not retrieved

  • Conveyance: Security Interest
  • Assignor: TELXON CORPORATION
  • Assignee: THE BANK OF NEW YORK
  • Correspondent: not retrieved
  • Context: Refinanced securitization lien; coincides with Telxon's 1999 financial distress.

• 1999-04-13 — Reel/frame not retrieved

  • Conveyance: Google labels this "Assignment of Assignors Interest"; given the 1999-09-09 release by Bank One, this is almost certainly a security interest / collateral assignment, not a true sale. Flag as ambiguous.
  • Assignor: TELXON CORPORATION (a Delaware corporation)
  • Assignee: BANK ONE, NA
  • Correspondent: not retrieved
  • Context: Securitization. ⚠️ This is the record that causes Google to list "Bank One Corp" as a current assignee — a known artifact. It is a released lien, not residual ownership; do not treat Bank One as a present owner.

• 1999-09-09 — Reel/frame not retrieved

  • Conveyance: Release of Security Interest
  • Assignor: BANK ONE, NA
  • Assignee: TELXON CORPORATION
  • Correspondent: not retrieved
  • Context: Release of the Bank One lien.

• 1999-09-09 — Reel/frame not retrieved

  • Conveyance: Security Interest
  • Assignor: TELXON CORPORATION
  • Assignee: FOOTHILL CAPITAL CORPORATION, AS AGENT
  • Correspondent: not retrieved
  • Context: Securitization (asset-based lender); lien runs ~6 years until the 2005 release below.

• 2002-04-08 — Reel/frame not retrieved

  • Conveyance: Assignment of Assignors Interest
  • Assignor: TELXON CORPORATION
  • Assignee: SYMBOL TECHNOLOGIES, INC.
  • Correspondent: not retrieved
  • Context: True ownership transfer — the post-acquisition cleanup assignment vesting Telxon's patent estate (including the '821 patent) in Symbol. This is a merger-integration transfer, not a shell-entity flip.

• 2005-01-05 — Reel/frame not retrieved

  • Conveyance: Security Interest
  • Assignor: SYMBOL TECHNOLOGIES, INC.
  • Assignee: JPMORGAN CHASE BANK, N.A.
  • Correspondent: not retrieved
  • Context: Securitization (Symbol credit facility).

• 2005-10-05 — Reel/frame not retrieved

  • Conveyance: Release of Security Agreement
  • Assignor: WELLS FARGO FOOTHILL, INC. (formerly FOOTHILL CAPITAL CORPORATION)
  • Assignee: TELXON CORPORATION
  • Correspondent: not retrieved
  • Context: Release of the 1999 Foothill lien.

• 2008-08-13 — Reel/frame not retrieved

  • Conveyance: Security Agreement Release
  • Assignor: JPMORGAN CHASE BANK, N.A.
  • Assignee: SYMBOL TECHNOLOGIES, INC.
  • Correspondent: not retrieved
  • Context: Release of the 2005 JPMorgan lien.

• 2012-07-16 — no assignment; anticipated expiration (term end).

Post-issuance ownership summary: exactly one genuine ownership transfer exists — 2002-04-08 Telxon → Symbol Technologies, Inc. Everything else in the record is lender security-interest paper and its releases. No assignment appears after 2008-08-13.

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Timeline diagram

timeline
    title Ownership of US 5334821
    1992 : Filed and assigned to Telxon
    1994 : Patent issues 2 August
         : Security interest to Bank of New York
    1996 : Security interest released
    1999 : Bank One and Foothill liens recorded
         : Bank One lien released
    2000 : Symbol Technologies acquires Telxon
    2002 : Ownership assigned to Symbol Technologies
    2005 : JPMorgan security interest recorded
         : Foothill release to Telxon
    2008 : JPMorgan lien released
         : Symbol sues Janam in Delaware
    2010 : Janam action settled with license
    2012 : Patent term expires

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NPE / troll-pattern signals

1. Shell-entity transfer — not present. The only ownership transfer is reel-not-retrieved 2002-04-08 Telxon → Symbol Technologies, Inc., an operating competitor. No entity with an "IP / Patents / Licensing / Holdings / Ventures" suffix appears in the chain; no registered-agent-service address appears; no single-purpose Delaware/Texas LLC takes title. Ownership ends at an operating company.

2. Known asserter in the chain — not present. Neither original assignee Telxon nor successor Symbol Technologies, Inc. (later the enterprise business of Motorola Solutions) matches the public NPE lists named in the task (Acacia, Marathon, IV, IPNav, Wi-LAN, Conversant/Mosaid, Vringo, Pendrell, Innovatio, MPHJ, Lumen View, Round Rock, Document Generation, Spangenberg entities). Symbol is a product company that ships the competitor products accused in the suit (MC50, MC70, MC3000, MC9000, PPT8800).

3. Repeat correspondent across the chain — insufficient data (not assessable). I could not retrieve any correspondent-of-record field from Assignment Center. This is the single most important gap: because the chain contains only one ownership transfer, a repeat-correspondent signal would at most show one recording firm, which would not meet the "recurrence" threshold anyway. Mark unclear / no evidence.

4. Cascading transfers — not present. The recorded events span 1992→2008 with years between entries, and all intermediate events are lender liens/releases, not chained LLC conveyances. Nothing resembling multiple back-to-back LLC assignments in <24 months.

5. Pre-litigation transfer — not present. The last ownership change is 2002-04-08; the first infringement suit naming the '821 patent was filed 2008-06-09 (Symbol v. Janam, D. Del. No. 1:08-cv-00340) — >6 years later. Far outside any 6-month set-up window. The pre-suit posture was clean for the opposite reason: Symbol had held title since the 2000 acquisition integration.

6. Bankruptcy fire-sale — not present (with a caveat). Telxon was severely distressed (1998 revenue restatement, SEC probe, securities class actions, steep sales decline, ~$107M debt assumed), but the exit was a stock-swap acquisition by Symbol completed Nov/Dec 2000, not a Chapter 7/11 sale of the patent estate. I found no evidence of a Telxon bankruptcy filing in the sources retrieved; I cannot fully exclude one and mark the sub-point unverified, but on the record available this is not a bankruptcy fire-sale. (Distinguish the separate 1999 divestiture of Telxon's Aironet radio division to Cisco — a strategic asset sale, not this patent.)

7. Privateering — not present. Symbol did not hand the patent to a third-party NPE to assert on its behalf; Symbol itself sued a direct competitor (Janam, founded by former Symbol executives) in its own name, and the 2010 settlement granted Janam a royalty-bearing license to Symbol's own patents (announced by Motorola Solutions/Symbol). That is classic operating-company enforcement, the inverse of privateering.

8. Defensive aggregator — not present. No RPX, AST, LOT Network, Unified Patents, or OIN entity appears anywhere in the chain. The patent was not neutralized via defensive aggregation; it simply expired on 2012-07-16.

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Verdict

Operating-company assertion.

Justification: the record contains a single genuine ownership transfer — 2002-04-08, Telxon → Symbol Technologies, Inc. — vesting title in a product company that shipped handheld mobile computers, and the patent was then asserted by that operating company in its own name against a direct competitor, Janam Technologies LLC, in Symbol Technologies, Inc. v. Janam Technologies LLC, D. Del. No. 1:08-cv-00340 (filed 2008-06-09), settled via a royalty-bearing license in December 2010. Every other recorded event is lender security-interest paper (1994, 1999, 2005) and its releases (1996, 1999, 2005, 2008) — no shell LLC, no known NPE, no defensive aggregator, and no rapid cascading transfers. The Google-listed "Bank One Corp" current-assignee entry is an artifact of a released 1999 security interest, not ownership, and should not be read as an NPE signal.

Verification links:

• USPTO Assignment Center search: https://assignmentcenter.uspto.gov/
• Google Patents legal-events view (reel/frame cross-check): https://patents.google.com/patent/US5334821/en#legalEvents
• Litigation docket: https://portal.unifiedpatents.com/litigation/Delaware%20District%20Court/case/1%3A08-cv-00340

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Open data gaps (must be closed before this is treated as final)

1. Reel/frame numbers for all eleven recorded events above — not obtained. They are the identifiers required for citation-grade assignment work.
2. Correspondent of record for each event — not obtained. Needed to run the repeat-correspondent test (Signal 3) properly. Note that with only one true ownership transfer, the maximum achievable here would be a single recording firm on the 2002 Symbol assignment; that cannot by itself support an NPE finding.
3. Execution vs. recording dates. The dates above are recording/event dates from Google's index. Execution dates for the 1999 and 2002 instruments may differ and should be confirmed.
4. Nature of the 1999-04-13 Bank One record (true assignment vs. collateral security interest) should be confirmed by inspecting the underlying instrument; the surrounding release strongly suggests a lien.

No fabricated data: any reel/frame, correspondent, or execution date not shown above was not obtained and is deliberately left blank rather than estimated.

I'll verify the citation record against live sources before building the prior-art analysis.

Let me verify the remaining references cited for this patent and its family.

Prior Art Analysis — US 5,334,821 "Portable point of sale terminal"

0. Scope, sources, and identifier discipline

Which document this is about. Everything below concerns exactly U.S. Patent No. 5,334,821 (the "’821 patent"), Portable point of sale terminal, Telxon Corporation, filed 1992-07-16, issued 1994-08-02 (Appl. No. 07/915,470). It is not JP 5334821 B2 (TOWA, resin sealing), nor the "47-5334821" Florida FEI number. Those unrelated "5334821" strings surface in keyword searches and have been excluded.

Sources actually used (be aware of the method). I did not issue a live call to a USPTO JSON API; the record below is reconstructed from the USPTO full-text image (patentimages.storage.googleapis.com PDF, the grant itself), the Google Patents record (https://patents.google.com/patent/US5334821/en), uspto.report, and the EPO/Espacenet record of the family counterpart EP 0 650 618 B1. I flag this so the citation list is not mistaken for a PatentCenter pull. Where I could not verify a detail, I say so rather than fill it in.

Date note (carried forward, not silently reconciled). The task header says "Current Date: April 26, 2026"; session metadata says 2026-10-01. This does not affect anything below; flagged for consistency with the earlier sections.

Two important definitions for reading the § 102 analysis. The ’821 patent's 10 claims are all tied to independent claim 1. Claim 1 has five elements, which I label throughout:

• E1 — hand-carryable housing with a front face
• E2 — a keyboard and a display mounted on the front face
• E3 — a power source located within the housing
• E4 — a first electromagnetic transceiver in the housing (over-the-air to/from a host computer)
• E5 — a second electromagnetic transceiver in the housing (over-the-air to/from a remote input/output device)

Under G.E. v. Nintendo / Net MoneyIN, § 102 requires every element, arranged as in the claim. Because claims 2–10 all depend from claim 1, a reference that cannot meet claim 1 cannot anticipate any dependent claim — it can at most be combined for § 103. This single point drives most of the conclusions below.

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1. The four citation sets (kept separate, because they have different legal weight)

Only Set A is "the patent citation list for 5334821" in the narrow sense. Sets B–D are added because they are the references that actually bear on validity, and a serious prior-art analysis that stopped at Set A would miss the closest art.

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2. Set A — References of record on the face of US 5,334,821

The grant lists three entries, but only two distinct references (the third is a reexamination certificate of the first):

A-1. US 4,947,028 (and US 4,947,028 B1) — Arbor International, Inc.

• Full citation: U.S. Patent No. 4,947,028, "Automated order and payment system," Appl. No. 07/221,536, filed 1988-07-19, granted 1990-08-07; assignee Arbor International, Inc. Certificate US 4,947,028 B1 issued 1993-06-08 (a reexamination certificate — same patent, not separate art).
• Description: A widely-distributed order computer terminal ("OCT") and central computer system ("CCS"). The OCT has an optical code reader (bar codes in catalogs/magazines), an alphanumeric keypad, voice recognition/synthesis, display, and reads magnetic-stripe, chip, and optical credit cards. It stores orders and transmits them to the CCS over telephone line, radio, satellite, or other links. The CCS performs inventory checks and credit authorization. (Sources: https://patents.google.com/patent/[US4947028A](/patent/US4947028A) ; https://uspto.report/patent/grant/4947028.)
• § 102 mapping: No anticipation of claim 1. E2 (keypad + display) is met; E4 is arguably met (OCT↔CCS radio/telephone transceiver); but the OCT does not disclose a second electromagnetic transceiver to a remote input/output device (E5) — its optical reader and card reader are integral to the OCT, not remote radio-linked peripherals; and the OCT is not described as a hand-carryable, front-face-keyboard POS housing (E1). Because claim 1 fails, the reference cannot anticipate claim 10 (magnetic card reader) or claim 9 (touch display) either, even though Arbor reads magnetic stripes. Best role: background + § 103 secondary reference.

A-2. US 5,189,287 — Parienti (Raoul Parienti)

• Full citation: U.S. Patent No. 5,189,287, "System for inputting, processing and transmitting information and data," Appl. No. 07/656,057, § 371(c) date 1991-03-06; PCT filed 1990-06-22 (PCT/FR90/00460); PCT publication WO 91/00574, published 1991-01-10; FR priority 1989-06-23 (FR 89 08653); granted 1993-02-23. Inventor: Raoul Parienti. (Sources: https://patents.google.com/patent/US5189287 ; https://uspto.report/patent/grant/5189287.)
• Description: A plurality of portable casings, each with a keyboard, screen, infrared transmitter/receiver, optical scanner, and an acoustic assembly (speaker + microphone), plus a card slot for dual-chip memory cards (and bank/credit cards). The casings talk to a computer center over a telephone network (acoustically) and to specialized terminals by infrared, and to each other. (Notably, its own cited art includes WO 87/07106 — a "hand-held terminal with optical bar-code reader and electromagnetic transmitting-receiving means for wireless communication with a base station" — showing the general concept was known.)
• § 102 mapping: This is the closest face-of-patent reference to the dual-communication architecture, but it does not cleanly anticipate. Mapping to claim 1:
• E1 — "portable casing," hand-carryable ✓ (subject to the Delaware construction, below)
• E2 — keyboard 4 + screen 5 ✓
• E3 — power source: not expressly described (the casing holds a memory card; no battery recitation located) ✗/unclear
• E4 — infrared transceiver to a specialized terminal/computer center ✓ (IR is electromagnetic radiation, though a court might read "electromagnetic transceiver" as RF/radio)
• E5 — the second link is acoustic (speaker/microphone over a telephone handset), which is not electromagnetic → fails under a literal reading. Parienti discloses one EM transceiver (IR) plus one acoustic transducer pair, not two EM transceivers.
• Consequence: no § 102 anticipation of claim 1, and therefore none of claim 2 (no spread spectrum, no narrowband-in-null anywhere), none of claim 3 (claim 3 requires the two links to operate on non-interfering electromagnetic frequencies — Parienti's are IR + acoustic), none of claims 5/6 (no interchangeable keyboards/battery interlock), none of claim 7/8 (no printer, no signature screen), none of claim 9 (no touch display), none of claim 10 (a credit card is insertable, but into a memory-card slot for chip-based payment — not a magnetic-stripe reader per claim 10).
• Best role: § 103 primary reference (portable terminal + keyboard + display + multiple communication paths), not a § 102 reference.

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3. Set B — References cited across the ’821 family (Google "Family Cites Families")

These come from prosecution of the divisional continuations and foreign counterparts. None is a clean § 102 reference against claim 1, but several are the real closest art.

B-6 in detail — US 5,107,100 (Symbol, Shepard et al.), the most structurally similar reference

• Full citation: U.S. Patent No. 5,107,100, filed 1988-11-17, granted 1992-04-21, Symbol Technologies, Inc. (Source: https://patents.google.com/patent/US5107100 ; US5107100 PDF at patentimages.)
• Description: A hand-held laser scanning head carrying, on-board: a keyboard, a display, a printer (thermal printhead, label roll, tear-off edge), and a radio transceiver "preferably using spread spectrum technology" to reach a remote site. In one embodiment the head (antenna 120) talks to a terminal 122 — expressly a cash register POS installation with display, keyboard, cash drawer, paper-tape receipt, recharger, decode module, and host database 136 — via antenna 140.
• § 102 mapping (this matters):
• E1 ✓ hand-held head housing
• E2 ✓ keyboard and display on-board the same housing
• E3 ✓ battery mounted within the base or the head, with recharger 132
• E4 ✓ on-board radio transceiver to a remote terminal/host
• E5 ✗ — only one transceiver is disclosed. The cash-register terminal is a stationary POS station, not a remote input/output device that the head separately radio-links to. There is no second transceiver in the head.
• Claim 2 ✗ — spread spectrum appears for the one link, but there is no second, narrowband carrier placed in a null of the spread-spectrum power spectrum.
• Claim 7 — printer ✓, signature-capture screen ✗ → no anticipation of claim 7.
• Claim 9 — no touch-sensitive display ✗. Claim 10 — no magnetic-stripe reader **✗.
• Conclusion: No claim of the ’821 patent is anticipated by US 5,107,100. It is, however, the strongest § 103 reference on the claim-1 sub-combination (housing + keyboard + display + battery + radio + printer), and it is notable that it is a Symbol Technologies patent — i.e., the art is owned by the entity that later acquired the ’821 patent.

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4. Set C — References cited by the EPO in EP 0 650 618 B1 (the ’821 family's European search report)

The EPO's search report on the EP counterpart identified the closest art explicitly. From the EP 0 650 618 B1 description:

• US 3,826,900 (NCR) — "hand-held optical scanner ... has a radio transmitter for transmitting data derived from reading such labels to a receiver located in a sales register." (§ 102 relevance: single wireless scanner→register link only; see B-1.)
• US 5,107,100 (Symbol) — described by the EPO as a hand-held scanning head with housing, keyboard, display, power source, laser scanning, and a radio transceiver ... for communication with a host computer, "which may be incorporated in a portable terminal or in a stationary terminal such as a cash register." (Same analysis as B-6 → no anticipation of claim 1; the EPO used it to define the closest prior art on the single-radio architecture.)
• US 4,879,650 — a point-of-sale register system: an electronic cash register connected to a central inventory control unit, plus an electronic weighing machine with an optical scanner, transferring weight and bar-code data to the register. Fixed POS equipment, no portability, no two radios → no claim anticipated; background only.
• The EPO's own characterization confirms the inventive core: the second electromagnetic transceiver to a remote input/output device, in a point-of-sale terminal, is the distinguishing feature (EP 0 650 618 B1, ¶¶ [0007]–[0011], published at https://patentimages.storage.googleapis.com/1f/f8/94/c575268393156d/EP0650618B1.pdf).

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5. Set D — Litigation art (Symbol v. Janam, D. Del. 1:08-cv-00340)

Per the earlier litigation section, Janam's invalidity theory against claim 9 was: US 4,569,421 (Sandstedt) anticipates, or Sandstedt in view of US 4,547,851 (Kurland) or Sandstedt in view of US 4,916,441 (Gombrich) renders obvious (Kurland/Gombrich supplying the touch-screen limitation). These are not on the face of the ’821 patent and were not in the EPO search report.

D-1. US 4,569,421 — Sandstedt, "Restaurant or retail vending facility" — the serious § 102 candidate

• Full citation: U.S. Patent No. 4,569,421, filed (priority) 1980-11-17, granted 1986-02-11, Gary O. Sandstedt. (Sources: https://patents.google.com/patent/[US4569421A](/patent/US4569421A)/en ; https://portal.unifiedpatents.com/patents/patent/US-4569421-A.)
• Description: A hand-held portable order-entry terminal 12 (waiter's terminal) with a keyboard 54, an optical pickup device 58 (bar code/OCR), memory, an alphanumeric printout (printer), and bi-directional communications using selected energy types — optical, RF, audio, inductive. The terminal pages and is paged by customer-station transceivers 14₁…14ₙ and also docks with pollable input/output stations 16₁…16ₙ feeding a local processor 22 and a central data processor 28.
• § 102 mapping: This is the only reference in the entire record that plausibly discloses two separate wireless communication links on one hand-held terminal — which is precisely why it was Janam's lead reference. Mapping:
• E1 ✓ hand-held portable terminal
• E2 — keyboard ✓; display on the terminal itself is not clearly disclosed (it has "operator instructional means" and a printer; the CRT 20 is external, in the kitchen). This is the fragile element — if the terminal lacks an on-front-face display, claim 1 is not anticipated.
• E3 — portable unit implies a battery; not expressly recited in the materials I retrieved.
• E4/E5 — two bi-directional links (host/local processor via the pollable interface; customer-station paging transceivers) → arguably ✓
• Claim 3 (two simultaneous, non-interfering EM links) — Sandstedt's links use selectable energy types; whether they are "electromagnetic" and "non-interfering" is contestable.
• Claim 2 ✗ — no spread spectrum / narrowband-in-null anywhere.
• Claim 9 ✗ on its own — Sandstedt does not disclose a touch-sensitive display, which is exactly why Janam had to combine it with Kurland or Gombrich. So under my reading, Sandstedt alone does not anticipate claim 9 despite Janam's contention; it is a § 102 candidate for claim 1 (and possibly claim 3) and a § 103 anchor for claim 9.
• Caveat: I have not obtained the full Sandstedt specification, so the display and power-source elements are stated with the uncertainty flagged. Anyone relying on this should pull the full text of US 4,569,421.

D-2. US 4,547,851 — Kurland and D-3. US 4,916,441 — Gombrich

• Cited by Janam only to supply the touch-screen display limitation of claim 9. I did not independently verify the bibliographic details of either reference within my search budget (the verification calls returned at the step limit). They are recorded here as reported in the earlier litigation section, not as confirmed citations. Potential § 103 role: combined with Sandstedt, supply a touch-sensitive display → relevant to claim 9 only through obviousness, not standalone § 102.

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6. Synthesis — reference-by-claim § 102 map

Strength key: ● = plausible § 102 anticipation · ◐ = contestable § 102, more likely § 103 · ○ = § 103 only · — = no relevance · (d) = dependent claim, so claim 1 must also be met.

The three findings that matter

1. No reference of record on the face of US 5,334,821 anticipates independent claim 1. US 4,947,028 (Arbor) and US 5,189,287 (Parienti) are the examiner-cited references, and both fail on element E5 (a second electromagnetic transceiver to a remote input/output device) — Arbor because its card/optical readers are integral, Parienti because its second link is acoustic, not electromagnetic. Since claims 2–10 all depend from claim 1, none of the examiner-cited references anticipates any of the 10 claims.

2. The strongest § 102 candidate for claim 1 is not on the face of the patent at all — it is US 4,569,421 (Sandstedt), raised only in the Janam litigation, and its anticipation theory hinges on two elements I could not confirm from the materials retrieved (an on-terminal display and an express power source). Whether Sandstedt anticipates claim 1 is genuinely contestable; it does not anticipate claim 9 on its own (no touch screen).

3. Claim 2 (spread spectrum host link + narrowband carrier in a null of the spread-spectrum power spectrum) is the true novelty and is essentially unaddressed by the entire cited corpus. No reference in Sets A–D discloses the "narrowband-in-the-null" relationship shown in the ’821 FIG. 8. The nearest disclosure of spread spectrum is US 5,107,100 (Symbol), but for a single link — it says nothing about a second narrowband carrier nulled into the first link's spectrum. If a defendant wants a § 102 attack on claim 2, it must find art outside this record.

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7. Verification status and open items (stated, not papered over)

• Verified (retrieved and read in this session): US 4,947,028 / B1; US 5,189,287; US 3,826,900 (snippet); US 5,107,100; US 4,569,421; EP 0 650 618 B1 search-report text; the ’821 grant and its claim set.
• Not independently verified: bibliographic details of US 4,547,851 (Kurland) and US 4,916,441 (Gombrich) — reported from the earlier litigation section; JP S62-108391 A, JP H01-319882 A, FR 2 494 466 A1, DK 0667019 T3, US 4,879,650 — titles/dates come from the citation lists, descriptions are provisional; the full specifications of US 4,569,421 (to confirm display and power-source disclosure) and US 5,110,226 / US 5,220,501.
• Corrections to watch: the earlier "Patent summary" section flagged that "5334821" also matches the unrelated JP 5334821 B2; that cross-contamination risk is real and those results are excluded here. The earlier litigation section noted a Studicata mislabel of Symbol v. Janam as a "Third Circuit (2010)" case; that does not affect the art analysis.
• Timing caveat to preserve: US 5,220,501 published 1993-06-15, after the ’821 priority date, so it is citable only under § 102(e) (its 1989-12-08 filing). DK 0667019 T3 published 2004, so any § 102 reliance must run through the underlying 1989 priority document, not the Danish translation.
• Recommendation for a final, citable version: pull the full texts of US 4,569,421, US 4,547,851, and US 4,916,441, and confirm the Sandstedt display/power disclosures before asserting or rebutting § 102 on claim 1.

Bottom line: the ’821 record's own citation list is thin and does not anticipate its claims; the novel core (two EM transceivers, with the narrowband-in-the-null second link) is essentially untouched by every reference the examiner, the EPO, and the litigants identified — with the single, contestable exception of Sandstedt against independent claim 1, which turns on two details I could not confirm and which I have flagged rather than assumed.

I'll ground the prior-art references before drafting the obviousness analysis. Where the earlier sections disagreed with a live source I'll flag it.

Obviousness Analysis — US 5,334,821 under 35 U.S.C. § 103

Scope note / identifier discipline. Everything below concerns U.S. Patent No. 5,334,821 A, Portable point of sale terminal (Telxon Corp., filed 1992‑07‑16, issued 1994‑08‑02). It is not the unrelated JP 5334821 B2 (TOWA, resin sealing) that surfaces in "5334821" keyword searches. Prior-art reference numbers below are reproduced exactly as they appear in the prior-art blocks of the patent page and in the live searches I ran; none have been auto-corrected.

Date caveat (flagged, not reconciled). The task text says "Current Date: April 26, 2026," while session metadata says 2026‑10‑01. This is the same discrepancy flagged in the earlier sections. It changes nothing here; the analysis is keyed to the 1992‑07‑16 critical date, not to today.

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1. Legal framework and the critical date

Because the application was filed before 2013‑03‑16, pre‑AIA § 103 governs. The governing test is Graham v. John Deere Co., 383 U.S. 1 (1966) 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 → objective indicia. Under KSR, a combination of known elements is obvious where (a) the elements were known, (b) the combination was "a predictable variation" using known methods to yield predictable results, or (c) there is an articulated reason — design incentive, market pressure, or a teaching/suggestion/motivation in the art — to make the combination.

Critical date: 1992‑07‑16. Prior art therefore includes anything "patented or described in a printed publication" more than one year earlier (§ 102(b)), and U.S. patents/applications with earlier effective filing dates (§ 102(a)/(e); pre‑AIA § 102(e) art is available for § 103 as of its filing date).

Level of ordinary skill (proposed). A POSITA here would be a person with a bachelor's degree in electrical engineering or computer science plus 2–4 years' experience in portable data‑collection terminals, hand‑held bar‑code systems, RF data links, or retail POS equipment — a field that by 1992 was mature and highly commercial.

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2. The prior-art universe actually on this page

The patent page exposes four distinct prior-art blocks, and they are not equivalent in date quality. This matters for § 103.

Key structural observation for the whole analysis: the examiner applied only US 4,947,028 and US 5,189,287. The far more on‑point references — US 5,107,100 (portable unit with on‑board keyboard, display, printer and transceiver) and US 5,110,226 (battery‑operated terminal with keyboard, display, power source and attached printer) — appear only in the family/divisional citation record. That is the single most important fact about the strength of this patent's § 103 position: the closest art was identified in the family but was not applied against the '821 claims.

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3. Claim‑1 mapping (the only independent claim)

Claim 1 requires: (a) hand‑carryable housing with a front face; (b) keyboard and display on that front face; (c) power source inside the housing; (d) a first electromagnetic transceiver inside the housing linking over the air to a host computer; and (e) a second electromagnetic transceiver inside the housing linking over the air to a remote input‑output device. The preamble — "A portable point of sale terminal" — was held to be a limitation by the Delaware court in the 2009 PI opinion (construed as "a portable computer terminal that is capable of handling a sales transaction").

Preliminary conclusion on claim 1. Every element is disclosed, and the only genuinely "combination‑defining" element is the presence of two separate over‑the‑air links in one hand‑carryable POS terminal (host link + peripheral link). No single reference on this record appears to disclose both links in one POS terminal, so claim 1 is a combination claim. The § 103 question is therefore whether the art supplies a reason to put two radios in one portable POS terminal. It plainly does — see § 5.

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4. Dependent-claim mapping

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5. The combinations, and why a POSITA would have made them

Combination A — Sandstedt '421 + Shepard '100 (primary § 103 attack on claim 1; also claims 3, 4, 7, 10)

Sandstedt (US 4,569,421) supplies the POS-capable, hand‑held frame: order/price/billing capability, keyboard, bar‑code/OCR input, printer output (FIG. 9), and — critically — a bi‑directional link "selectively utilizing… optical, RF, audio and inductive energy" to both a local processor and a remote processor, plus customer‑station paging transceivers (a second, independent over‑the‑air path to a remote device). Shepard (US 5,107,100) supplies the integrated portable assembly — on‑board keyboard, display, printer and radio transceiver, "preferably using spread spectrum technology" — proving that by 1992 it was conventional to build a single hand‑held unit with the terminal's I/O, printing and radio all on board.

Motivation (KSR‑sufficient):

1. Same field, same problem. Both address freestanding, cable‑free portable data‑entry in retail/order‑taking. Sandstedt expressly frames the goal as eliminating the fixed station; Shepard's stated object is "on‑board transmission and reception of electrical signals."
2. Predictable combination with a known benefit. Adding a second radio (to reach the peripheral scanner) to a unit that already contains a radio (to reach the host) is the mechanical union of two known elements, each performing its known function — no change in their respective principles of operation. KSR, 550 U.S. at 416–17.
3. The art itself supplies the two‑link teaching. Sandstedt's express enumeration of multiple, coexisting energy types (optical/RF/audio/inductive) and its paging channel are a direct suggestion to provide more than one wireless path from the terminal.
4. Industry pull. Wireless bar‑code data collection was the commercially dominant direction in 1991–92 — corroborated here by the family's citation of NCR US 3,826,900 (cordless scanning probe, 1974), Octec FR 2 494 466 (remote data‑capture units to a central unit), and the Norand spread‑spectrum/mobile‑radio family. A POSITA facing the '821 problem had an explicit design incentive to go wireless on both links.

Combination B — Norand '226 + Shepard '100 (claim 1 elements (a)–(c) and claim 7)

Norand US 5,110,226 is, on its face, the cleanest single reference for the terminal hardware: its claim 15 recites "a data entry terminal unit including a keyboard and a display disposed in an upper face thereof… a self‑contained terminal power source… a printer unit attached," and its stated object is to add printing "without impairing the portability." Add Shepard's on‑board spread‑spectrum radio and Sandstedt's second link, and claim 1 and claim 7 fall. Motivation: adding RF data transfer to a portable printing terminal is the canonical 1990s upgrade; both references are in the portable data‑collection art and were cited in this very patent family.

Combination C — Arbor '028 + Parienti '287 (examiner's own art; gets claims 1, 7, 9, 10)

These are the two references the examiner actually applied, and together they cover nearly everything but the dual‑radio feature:

• Arbor '028 — POS/payment terminal with optical reader, keypad, magnetic‑stripe card reading, printing, and host communication over telephone or radio; the preamble ("capable of handling a sales transaction") is met head‑on.
• Parienti '287 — portable casing with card slot, keyboard, screen, infrared transmitter and receiver, bar‑code scanner, and communication with both a computer center and specialized terminals/other casings; claim 9 covers credit‑card payment by insertion.

Parienti is significant because it discloses two independent communications channels in one portable unit (IR to nearby terminals/casings; acoustic/telephone to the central computer). A POSITA combining Arbor with Parienti to make a portable POS terminal with a host link and a separate peripheral link is doing exactly what KSR describes.

Combination D — anything above + NCR '900 / Octec FR 2 494 466 + Omron '294 / JP S62‑108391 (the "remote input‑output device")

The second transceiver of claim 1 (e) has a dedicated, low‑tech antecedent: the cordless scanning probe of US 3,826,900 and the Octec remote data‑capture units of FR 2 494 466. Either makes the "remote input‑output device" link an old and well‑known expedient, removing any argument that a second over‑the‑air path was inventive.

Combination E — claims 5 and 6 (interchangeable keyboards; battery interlock)

• Claim 5 is well supported: the family cites DK 0667019 T3, "Handheld data collection system with interchangeable modules" (subject to the date caveat in § 6), and Norand's modular‑terminal art describes a housing built from a base module, an intermediate keyboard module, and a display module. Providing a recess in the front face to removably seat one of several keyboards is an obvious mechanical implementation of modularity.
• Claim 6 (keyboard removable only with the batteries out) is not disclosed by anything on this page. It is a classic candidate for a KSR "obvious design choice / safety‑interlock" argument — the specification itself supplies the rationale ("prevents removal of the keyboard assembly while the terminal is powered, whereby inadvertent electrical hazards… are minimized"), and it is a known engineering convention to place service fasteners behind a battery door so a device must be depowered before opening. But that is an attorney argument, not a documentary disclosure; without additional art (hand‑held computer service manuals, Norand/Telxon service documentation, or an interlock patent), claim 6 is the second‑strongest claim after claim 2.

Combination F — claim 9 with Kurland '851 or Gombrich '441

This is precisely the theory Janam advanced in the Delaware action: Sandstedt '421, alone or in view of US 4,547,851 (Kurland) or US 4,916,441 (Gombrich), the touch‑screen references supplying claim 9's "display adapted to sense the manual selection of information." Norand's own art likewise describes a data terminal whose "active area of the display screen is covered by a touch sensitive overlay screen." Motivation: by 1992, replacing menu‑selection keystrokes with an on‑screen touch target in a portable terminal was a routine, well‑understood ergonomic substitution with a predictable result.

Combination G — claim 2 (spread spectrum + narrowband‑in‑the‑null)

Here the record fails. Shepard '100 expressly discloses spread spectrum, so claim 4 is essentially anticipated. But the claim‑2 refinement — placing the narrowband carrier "at the frequency of a null of the power spectrum" of the spread‑spectrum signal — is not disclosed by any reference on this page. The '821 specification itself supplies the rationale (a 100× power differential can be tolerated without excessive interference, FIG. 8), which is the kind of stated advantage that supports non‑obviousness unless a defendant finds art teaching null‑filling/notch placement of narrowband channels within a spread‑spectrum band (a technique that was known in the RF coexistence literature and in later IEEE 802.11 practice, but is absent from this record).

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6. Claim‑by‑claim vulnerability summary

Net assessment. Claims 1, 3, 4, 9 and 10 are exposed to a strong § 103 attack built on references already inside this patent's own family record. Claims 5 and 7 are moderately exposed. Claims 2, 6 and 8 are the residual points of novelty — and of those, claim 2 is the one with real claim‑differentiating value, because it is the only claim reciting a specific, technically non‑trivial coexistence scheme.

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7. Objective indicia and counter‑arguments the patent owner would raise

1. Unexpected results (claim 2 only). The specification asserts the spread‑spectrum link can run at a power level "as much as two orders of magnitude greater" than the narrowband link "without excessive interference." If the owner can tie measured data to the claimed null alignment, that is a classic unexpected‑result argument — but it is confined to claim 2 and requires a nexus showing.
2. Teaching away — weak. None of the cited art teaches away from a dual‑radio portable POS terminal; if anything, Sandstedt and Parienti teach toward multiple wireless channels.
3. Commercial success. Telxon's own handheld/RF product line (and its Aironet direct‑sequence 2.4 GHz radios, per the earlier Assignment section) could support a secondary‑considerations narrative — but no verified sales/nexus evidence is in the record, and the accused‑product fight in Delaware was decided on claim construction, not on objective indicia.
4. The Shepard reference cuts against the owner. US 5,107,100 is a Symbol Technologies patent — the entity that acquired the '821 patent in 2002. A defendant can argue, with force, that the eventual owner's own 1988‑priority patent already described a hand‑held unit with keyboard, display, printer and a spread‑spectrum radio transceiver, making the '821 claims a straightforward extension of the assignee‑family's own work.

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8. What I could not verify (stated rather than assumed)

1. DK 0667019 T3 date integrity. The Family‑Cites entry shows "1989‑06‑07" as priority but "2004‑01‑26" as the publication date, with "Broadcom Corp" as the listed assignee. As a printed publication the T3 is post‑critical‑date and cannot itself be § 102(b) art. Qualifying prior art for claim 5 must be the parent EP/WO publication (a 1990‑era document, not retrieved). Treat the claim‑5 combination as provisional pending retrieval of the parent publication.
2. Full texts of the secondary references. Characterizations of US 4,947,028, US 5,189,287, US 5,107,100, US 5,110,226, US 4,569,421, US 3,826,900 and FR 2 494 466 above rest on the abstracts, claims and specification passages surfaced in search, not on a full element‑by‑element read of every drawing.
3. Norand modular‑terminal patent numbers. The "interchangeable keyboard/display module" and "touch‑sensitive overlay" disclosures come from Norand abstracts and from US 5,539,193; several Norand abstracts appeared without a retrievable patent number. The specific numbers (and their pre‑1992 § 102(e) dates) must be pinned down before any claim‑5/claim‑9 chart is filed.
4. Sandstedt's full disclosure. My confirmation of US 4,569,421's content is from the Google Patents definitions block plus the Janam invalidity theory recorded in the earlier Litigation/PTAB sections. I did not verify how the Delaware court resolved Janam's invalidity prong, and I do not assert an outcome.
5. No new-art search. I have analyzed the references on this page plus the litigation‑supplied art. A complete § 103 analysis would also sweep the 1990–1992 RF‑coexistence literature for claim 2 (null/notch placement of narrowband channels within a spread‑spectrum band) — that is the one gap that could flip claim 2.

Sources: https://patents.google.com/patent/US5334821/en (authoritative text, prior‑art blocks); https://patents.google.com/patent/US5107100 and http://www.everypatent.com/comp/pat5107100.html (Shepard); https://uspto.report/patent/grant/[5,110,226](/patent/5110226) and the US 5,110,226 PDF (Norand, Sherman et al.); https://patents.google.com/patent/[US4947028A](/patent/US4947028A) and https://uspto.report/patent/grant/[4947028](/patent/4947028) (Arbor); https://uspto.report/patent/grant/[5189287](/patent/5189287) (Parienti); https://patents.google.com/patent/[US4569421A](/patent/US4569421A)/en (Sandstedt).