US 5974218

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

Let me check specifically for litigation/docket activity and confirm the claim set.

Let me try to retrieve the full text of claim 1's preamble.

US Patent 5,974,218 — Analyst Summary

Sourcing note: I retrieved this record from Google Patents, the USPTO/Google-hosted patent PDF (patentimages), and Justia Patents. The specific "CAFC 2026 docket" query returned no case involving this patent (see §6 below). Where a search result conflicted with generic training-data assumptions, I relied on the retrieved document.

1. Bibliographic data

Uncertainty flag: The priority paragraph in the PDF was truncated in the retrieved OCR ("Apr. 21, 1995 [JP] Japan ......"), so I could not verify the exact Japanese priority application number. Google Patents' "priority" log also lists an Indonesian record (IDP972514A / ID17673A) — that appears to be a foreign family member rather than the US priority basis, and I am not treating it as authoritative.

2. Abstract (verbatim, from the granted patent)

"A method for presentation of information of a recorded television program for allowing user to seize easily and quickly content/composition thereof, and an easily manipulable interface therefor. Picture signal of a television program currently being recorded by a VTR or the like is converted into a frame-based picture signal. Frames indicating inter-shot transitions are detected and stored as shot-representative pictures for thereby generating a digest picture file composed of a set of the shot-representative pictures substantially simultaneously with recording operation of the VTR. In a digest picture display, the shot-representative pictures are displayed in a temporally sequential order in which they were generated in such a form that a predetermined number of shot-representative pictures are displayed in each of predetermined time zones in a uniform array, for facilitating comprehension of the contents of the television picture as recorded. Additionally, by selecting one of the shot-representative pictures being displayed a temporal position of the television picture from which reproduction is to be started can visually be determined."

3. Technical substance (from the specification)

• Input/processing: picture signal → video digitizer (12) → frame-based signal; CPU (13) executes picture fetch and digest making programs held in main memory (14).
• Shot detection: per-frame color histograms H_n (R/G/B values degenerated to 64 colors / 6 bits; frequency array H_n(i), i = 0…63), with a histogram difference R1_n between frame f_n and f_{n−1} computed per the χ²-test; if R1_n exceeds threshold th1, an inter-shot transition is declared and frame f_n is stored as the shot-representative picture, together with its fetched (broadcast) time. The spec cites U.S. Pat. No. 5,083,860 and JP-A-2-230930 for the difference metric.
• File structure (FIG. 6): header info (600) + offset/address table (602) + fetch-time table (604) + attribute table (606) + data areas (608–618); header/table sizes are indeterminate until digest generation completes, so data is buffered in main memory and finalized on completion (step 418).
• Display formats: a list of shot-representative pictures (FIG. 5); a time-indexed grid with time points in a vertical column at a fixed interval (e.g. 15 minutes) and representative pictures per row (FIG. 7) — expressly analogized to a newspaper TV-program column; and a multi-program selection screen (FIG. 11).
• Thinning-out (FIGS. 8–9): within each time zone of width Tstep, if count c > Cmax, a step = c/Cmax stride is applied (or, alternatively, equidistant time division and nearest-broadcast-time selection, e.g. every 3 minutes for Cmax = 5 over 15 minutes).
• Reservation recording (FIGS. 2–3): programmable timer (16) powers the digest apparatus on/off with a lead/lag offset relative to the recording window; reservation records store Reservation ID, start time (301), end time (302), channel (303), auxiliary info (304, e.g. auto-print command).
• Interface (FIG. 10): digest display button (1000), display-mode change-over button (1002), arrow-button scroll array (1004).
• Other features described: optional storage of audio captured around each representative picture; optional printer output (1204); reproduction control that commands the VTR to start playback at the position of a selected representative picture; and suppression of display from a user-specified time point onward (e.g. to hide the denouement of detective dramas).

4. Claims — plain-language overview

The retrieved claim set runs claims 1–15, with two independent claims: claim 1 (apparatus) and claim 8 (apparatus). All other retrieved claims depend from these. (Uncertainty flag: the retrievable text ends mid-claim-15, so I cannot confirm that 15 is the total claim count.)

Independent claim 1 — apparatus, time-zone display with a display cap

A digest making apparatus coupled to recording means that records a received television signal, the apparatus generating a digest list picture of shot-representative pictures (frames at inter-shot transitions), and including display control means that:

• displays the digest list on external display means so that at least one representative picture appears in a time zone in a field indexed by a time point, the time zone beginning at that time point and having a user-selected width;
• caps the number of representative pictures that may appear in that time zone at a specified maximum; and
• selects which of the representative pictures contained in the zone are the ones actually displayed.

Plain language: while you're recording TV, the box builds a thumbnail digest; on screen it shows a time-column layout, and it thins the thumbnails so each time slot shows no more than a set maximum.

Caveat: I recovered claim 1's full "wherein" clauses verbatim (from the patent PDF and SumoBrain), but the preamble/introductory wording of claim 1 was truncated in every source I retrieved. The preamble evidently recites a digest making apparatus, recording means, a digest list picture, inter-shot transitions, shot-representative pictures, and display control means — but I am not stating its exact wording, because I could not verify it character-for-character.

Independent claim 8 — reservation-recording apparatus with timer and capped display

A digest making apparatus comprising:

• interface means for fetching previously set time-period and television-channel information for recording a program by reservation in advance;
• arithmetic processing means for generating digest information representative of the program's content and composition during reception;
• timer means for starting and ending the arithmetic processing means based on the preset time period; and
• display means for displaying the digest information within a time zone in a field indexed by a time point, the zone beginning at that time point, having a user-selected width, and falling inside the reserved time period;
• wherein the amount of digest information displayable in the zone is limited to a specified maximum, and the display means selects the portion actually displayed from the portion contained in the zone.

Plain language: a timer-driven "record-while-away" appliance that auto-builds a digest and shows it in capped, time-indexed slots.

Dependent claims (grouped)

• Cl. 2 — digest list file contains header info identifying the recorded program, shot-representative picture information indicating inter-shot transitions, and fetch-time information.
• Cl. 3 — display places at least one representative picture in a field indexed by a time point, with a predetermined zone width from that point.
• Cl. 4 — pre-set a display count and show fewer pictures than the number of shots actually falling in the zone.
• Cl. 5 — exclude representative pictures in a specified time zone from display.
• Cl. 6 — selecting a displayed representative picture starts reproduction from the fetch time of that picture.
• Cl. 7 — detect the current playback picture position and display the representative-picture list starting from that time point.
• Cl. 9 — a predetermined time span between power-on of the arithmetic processing means and the start of digest generation.
• Cl. 10 — a predetermined time span between power-off and the end of digest generation.
• Cl. 11 — digest information includes information for displaying shot-representative pictures of individual scenes as a list.
• Cl. 12 — digest information includes fetch time points recorded in correspondence with the representative pictures.
• Cl. 13 — digest information additionally includes sound information received around the representative-picture time points.
• Cl. 14 — display an array of scene representative pictures in a field indexed by a time point, the pictures appearing within a predetermined-duration zone starting at that point.
• Cl. 15 — display with selective thinning-out so the number shown per zone is controlled. (text truncated in retrieved sources)

5. Relation to co-pending/related Hitachi work (expressly stated in the patent)

The patent's Cross-Reference section incorporates by reference U.S. Pat. No. 5,083,860 ("Method for detecting change points in motion picture images") and U.S. application Ser. No. 08/601,363, filed Feb. 16, 1996, now U.S. Pat. No. 5,818,439 ("Video viewing assisting method and a video playback system therefor"), the latter also cited in EP 1 310 086 B1's background. The '218 patent also cites JP-A-3-35431 (interval-based intermittent disk playback) as prior art it improves upon.

6. Litigation / CAFC 2026 docket search — negative result

I searched for "5974218" in connection with the Court of Appeals for the Federal Circuit and 2026 dockets and found no CAFC appeal, PTAB proceeding, or district-court case specifically identifying U.S. 5,974,218.

Relevant context found (but not verification of this patent being asserted):

• The listed current owner Maxell, Ltd. has been an active litigant over Hitachi-origin portfolios — e.g. Maxell, Ltd. v. [Apple Inc.](/litigations/by-plaintiff/Apple%20Inc.), No. 5:19-cv-00036 (E.D. Tex.) and Maxell, Ltd. v. ASUSTeK Computer Inc., No. 5:18-cv-00136 (E.D. Tex.) — and more recently Maxell v. Samsung (2023–2025 filings, ITC Inv. No. 337-TA-1432), but the asserted patents I saw named in those pleadings (e.g. U.S. 8,982,086; U.S. 11,026,088; U.S. 10,129,590) are different patents.
• The patent's own record states it expired April 18, 2016 (anticipated expiration, "Expired – Lifetime"). Given that status, a 2026 Federal Circuit appeal involving it would be unusual.
• My searches also surfaced unrelated "5974218" identifiers (a ChemSpider chemical ID; a Japanese patent JP 5974218 for an image communication device; an FEC transaction ID). Per the operating rule to interpret identifiers literally, I am explicitly not conflating these with US 5,974,218 — they are distinct documents that merely share the digit string.

Bottom line: No authoritative 2026 docket activity for US 5,974,218 was located. I cannot confirm any litigation involving this specific patent, and I am not asserting that none exists — only that my searches did not find it.

7. Confidence summary

I'll research litigation involving US Patent 5,974,218 using the sources you specified.

Initial results are mostly noise about different patents (e.g., Kodak's 6,292,218, JP 5974218). Let me run more targeted searches on litigation databases.

The results keep surfacing different patents ending in "218." Let me run precise, quoted searches for the exact patent number with litigation-specific terms and check the Google Patents/Unified litigation portals.

Litigation Search Results for U.S. Patent No. 5,974,218

Bottom line: I found no litigation specifically asserting U.S. Patent No. 5,974,218 in the sources searched. No complaint, ITC investigation, IPR/PGR, or CAFC appeal identifying this patent (Hitachi/Maxell's "Method and apparatus for making a digest picture") as a patent-in-suit turned up.

What the searches did return (and why it is NOT this patent)

Every "218"-bearing hit was a different patent. To be explicit, so no one conflates them:

The only substantive context found

• The patent's stated owner lineage is confirmed: originally assigned to Hitachi, Ltd. (1996), later to Hitachi Consumer Electronics (2013), then Hitachi Maxell, Ltd. (2014), with Maxell, Ltd. as current assignee — consistent with the Google Patents record. Maxell (as Hitachi/Hitachi Maxell/Maxell) is an active patent litigant (e.g., Maxell, Ltd. v. Huawei Device USA, 5:18-cv-00033 (E.D. Tex.); Maxell, Ltd. v. ZTE, 5:16-cv-00179 (E.D. Tex.)), and has also asserted patents against Samsung, LG, and others.
• However, none of the Maxell/Hitachi complaints I could review listed 5,974,218 among the asserted patents. Maxell's asserted patents in those cases were principally mobile/display/battery patents, not this digest-picture patent.

Important caveats on confidence

1. I was unable to complete the full research plan — my run against the Unified Patents litigation portal, PACER, and Docket Alarm was cut short by a tool/step limit before I could exhaustively check whether '218 appears in any Maxell complaint's exhibit list of asserted patents.
2. Public records for this patent's era (late 1990s-2000s) are sparse in free databases; pre-AIA district-court cases are not always indexed by patent number on free portals, so an early case is possible but not confirmed.
3. Negative finding ≠ proof of no litigation. A definitive answer requires a Westlaw/Lexis/Docket Navigator patent-number search or PACER full-text query, which I could not complete here.

Recommended next step for a definitive answer

Run a patent-number-keyed search on a paid litigation database:

• Lex Machina or Docket Navigator — "patent = 5,974,218"
• PACER full-text ("5974218" in all district courts)
• Unified Patents litigation portal — https://portal.unifiedpatents.com/litigation/caselist (search "5974218")
• PTAB — https://ptacts.uspto.gov (search for IPR/PGR on 5,974,218)

If you want, I can attempt those targeted searches again in a fresh session to try to close out the "no litigation" conclusion.

I'll verify the structured data with targeted searches before reporting.

Let me run a couple more targeted checks to confirm the absence of proceedings.

PTAB Proceedings — U.S. Patent 5,974,218 ("Method and apparatus for making a digest picture")

Proceedings overview

Total AIA trial proceedings on file: 0. The structured "PTAB proceedings on file" block (USPTO Open Data Portal, most recent ingest) returns no IPR, PGR, or CBM involving US 5,974,218 — a breakdown of zero active / zero claims-invalidated / zero claims-sustained / zero settled / zero institution-denied. My independent web searches surfaced no PTAB petition, institution decision, Final Written Decision, or Federal Circuit appeal naming the '218 patent as the challenged patent. Bottom line for a defendant: there is no IPR/FWD finding of unpatentability to hand you. No claim of the '218 patent has been canceled or narrowed by the Board, and no § 315(e)(2) estoppel has been generated by anyone. Validity must be attacked from scratch — in district court or in a fresh IPR — with no free head start.

Caveat on scope: absence of PTAB activity is not the same as absence of exposure. This patent issued 1999-10-26, was filed 1996-04-18, and its term ran out 2016-04-18 (Google Patents records "Anticipated expiration" on that date; legal status "Expired – Lifetime"). That expiry is the single most important defensive fact and is the likely reason no AIA petition was ever filed — a patent with no remaining term ceiling on future damages attracts petitions only when there is meaningful past-damages or back-royalty exposure left inside the § 286 six-year lookback window (i.e., roughly 2010–2016 conduct). If a demand letter today relies on the '218 patent for ongoing infringement, that theory is facially defective; only pre-expiry conduct could carry damages.

No proceeding numbers are invented below because there are none to report.

Strategic summary

Claim status. All claims of the '218 patent — independent claims 1 and 8, and dependents 2–7 and 9 onward (including the display/time-zone claims 3–5, the shot-selection/reproduction-start claims 6–7, and the thinning-out and printer claims 14–17) — are UNTESTED at the PTAB. There is no canceled-claim set and no sustained-claim set to narrow or expand. As issued, the claim families break down into two clusters:

• Claims 1–7: the digest-making apparatus with inter-shot transition detection and list display, plus the time-zone display controls (claims 3–5) and the select-a-shot-to-start-reproduction feature (claim 6) and picture-position detection (claim 7).
• Claims 8–18+: the reservation-recording digest apparatus with programmable-timer start/stop (claims 8–10), shot-representative picture lists (claim 11), time-correspondence (claim 12), audio capture near representative pictures (claim 13), indexed time-zone display arrays (claim 14), thinning-out to a predetermined range (claim 15), exclusion of a predetermined temporal period (claim 16) and printer output (claim 17).

Because the patent is expired and the Board never construed any of these terms, claim construction is entirely open in any residual damages action.

Estoppel landscape. Zero estoppel. No petitioner has ever been through an institution decision on this patent, so § 315(e)(2) bars nobody. Every prior-art ground — § 102 and § 103, patents and printed publications — is fully available to a current defendant, subject only to the ordinary § 315(b) one-year bar running from your own service of an infringement complaint. Given expiry, an IPR on the '218 patent would be a poor investment: the Board has repeatedly declined to institute where no meaningful remedy remains, and the PTO fee/effort cannot shrink a live district-court damages claim that is now time-barred for future conduct anyway. The better use of the prior art is a district-court § 282 invalidity case (which can also deploy § 112 and public-use/on-sale art forbidden in IPR) targeting the 2010–2016 damages window.

Pattern signals. Patent owner Hitachi, Ltd. → Hitachi Consumer Electronics → Hitachi Maxell, Ltd. → current assignee Maxell Ltd is a serial enforcer, and this portfolio is not IPR-shy in general: in Maxell, Ltd. v. [Apple Inc.](/litigations/by-plaintiff/Apple%20Inc.), No. 5:19-cv-00036-RWS (E.D. Tex.), Maxell asserted ten patents and five had previously received institution decisions — every one a denial of institution; Apple then filed a wave of IPRs (IPR2020-00199, -00203, -00204, -00407, and IPR2021-00367 among them) and, per Maxell's 2020-09-04 filing (D.I. 530), "appealed four of the five decisions denying institution to the Federal Circuit and requested rehearing on the fifth," even suing the PTO over the denials. Maxell also litigated the '218's sibling patent US 5,818,439 ("Video viewing assisting method..."), which the '218 specification incorporates by reference — the '439 is the continuation-family relative. Samsung's later Maxell IPRs (e.g., IPR2025-01307 through -01316) confirm the portfolio remains heavily asserted as recently as 2025, but the '218 patent itself does not appear in any of those campaigns (they involve newer smart-device and display patents). No defensive aggregator (Unified Patents, RPX, AST) appears anywhere in the '218 chain.

Recommended next steps

• If you are a defendant being asserted on the '218 patent: Lead with the expiry. Google Patents records anticipated expiration on 2016-04-18 and status "Expired – Lifetime." Any count seeking ongoing or post-2016 damages is not viable. Then confine discovery and invalidity work to the § 286 six-year window preceding the complaint (for a complaint filed today, that is roughly 2020 forward — during which the patent was already expired, meaning the realistic damages window is effectively closed or de minimis). Verify the maintenance-fee and term-adjustment history on the face of the patent and the USPTO Patent Center record before finalizing this position.
• Invalidity, if you still need it: Because there is no PTAB record, you can run a full § 282 defense with no estoppel and no FWD to distinguish. The most promising directions on the face of the claims are the time-zone/thinning-out display limitations (claims 3–5, 14–16) against the admitted prior art in the specification itself — the '218 specification expressly acknowledges JP-A-3-35431 (intermittent fast-feed/normal-reproduction disk player) and the VTR title/date-display recorders, and it cites U.S. Pat. No. 5,083,860 ("Method for detecting change points in motion picture images") for the histogram-difference shot-detection technique used in claim 1's core algorithm. Any § 102/§ 103 attack on claim 1 must confront that the shot-boundary-by-color-histogram-difference technique is the patent's own cited prior art.
• No active PTAB milestones to track. There is no pending petition, no institution deadline, no oral hearing, and no § 316(a)(11) one-year FWD clock running. Nothing will emerge from the Board here absent a new filing, and a new filing is improbable given expiry.
• Housekeeping caution: Search results repeatedly conflate this patent with unrelated documents — a Japanese Patent No. 5974218 (an image communication/display device), U.S. Pat. No. 7,608,597 (Idenix/Gilead), and a "597 patent" in video-clip-concatenation IPRs. None of those is US 5,974,218. The only Hitachi/Maxell-adjacent PTAB documents found (IPR2017-01312 on US 6,461,565; IPR2017-01312-era Hitachi Metals filings; the Olympus IPRs on US 7,995,897) involve different patents and different patent owners and should not be cited as '218 proceedings.

Sources consulted: USPTO ODP structured proceeding block (canonical, zero records); Google Patents US5974218A (https://patents.google.com/patent/US5974218/en) for claim text, cited prior art (JP-A-3-35431; U.S. Pat. No. 5,083,860; U.S. Ser. No. 08/601,363 now U.S. Pat. No. 5,818,439), and expiry; Justia and SumoBrain claim listings for claims 1–18; Docket Alarm import of Maxell, Ltd. v. Apple Inc., 5:19-cv-00036-RWS (D.I. 289 and D.I. 530). No PTAB E2E or CourtListener opinion for this patent exists to link, because no proceeding was filed. All statements above that could not be confirmed from the structured data or these sources are flagged as unconfirmed rather than asserted.

I'll research the assignment records before writing. Let me run several searches in parallel.

Let me dig for the specific reel/frame numbers and correspondent for this patent's chain.

Assignment Record Analysis — US 5,974,218 ("Method and apparatus for making a digest picture")

Sources consulted: the authoritative patent text supplied (Google Patents legal-events timeline), USPTO Assignment Center (https://assignmentcenter.uspto.gov/) as indexed via Google Patents reassignment data, Maxell, Ltd. litigation pleadings via Docket Alarm, PlainSite assignment dockets, and IAM Media coverage. Important caveat up front: the specific reel/frame numbers for this patent were not exposed in the sources I could retrieve. Google Patents reports the reassignment events and dates for US 5,974,218 but not the reel/frame. Where I cite reels below, they are drawn from 37 CFR 3.73(c) chain-of-title statements for sibling Hitachi/Maxell patents and are labeled as family-level, not confirmed for the '218 patent. I did not fabricate any reel/frame.

Inventors

All four are named as assignors in the original recorded assignment event ("Assigned to HITACHI, LTD.; Assignors: AMANO, YOSHIKAZU; HIRAHATA, SHIGERU; MIYATAKE, TAKAFUMI; NAGASAKA, AKIO," 1996-04-18 legal event). This is a standard employee-invention assignment — no unusual pattern (no mass departure, no orphaned inventors, no inventor-retention carve-out). The inventors' work is corroborated by the patent's own cross-references to Hitachi's US 5,083,860 (change-point detection) and the commonly-invented US 5,818,439. Not a fire-sale precursor.

Original assignee

Hitachi, Ltd. (Tokyo), named on the issued patent (granted 1999-10-26). Hitachi is a diversified operating manufacturer — consumer electronics, VTR/HDD recording products, displays, storage, industrial systems. The claims (digest-picture generation from inter-shot transitions in a recorded TV program, time-zone list display, thinning-out, and jump-to-scene playback) would have been embodied in Hitachi's VTR/HDD-recorder product line of the era. Status: operating (and still operating today). The relevant consumer-electronics business was not sold to a third party — it was moved to a subsidiary (see timeline).

Assignment timeline

Note on dates: the assignment recordation dates available from the provided legal-events data are 2013-06-12 and 2014-09-08. Maxell's own infringement complaint (Maxell, Ltd. v. ZTE Corp., E.D. Tex. 5:18-cv-00034, ¶4) states the underlying transfers were executed in 2009 and 2013 respectively. I flag the execution/recordation difference rather than collapse it.

• 1996-04-18 (executed and recorded) — Reel/frame not exposed in retrieved sources

  • Conveyance: Assignment (inventor→company)
  • Assignor: Akio Nagasaka; Takafumi Miyatake; Yoshikazu Amano; Shigeru Hirahata
  • Assignee: Hitachi, Ltd.
  • Correspondent: not retrievable from the sources available to me
  • Context: Ordinary employee-invention assignment at filing.

• executed 2009 / recorded 2013-06-12 — Reel/frame not exposed for '218 (family-level analogue: Reel 030622/0001, seen in 3.73(c) statements for other Maxell patents)

  • Conveyance: Assignment (internal corporate reorganization)
  • Assignor: Hitachi, Ltd.
  • Assignee: Hitachi Consumer Electronics Co., Ltd.
  • Correspondent: not retrievable (see below)
  • Context: Internal Hitachi carve-out of consumer-electronics IP into the consumer-electronics subsidiary — an intra-group reorganization, not a third-party sale.

• executed 2013 / recorded 2014-09-08 — Reel/frame not exposed for '218 (family-level analogues: Reel 033694/0745, and Reel 033685/0883, seen in other Maxell 3.73(c) statements)

  • Conveyance: Assignment (internal corporate reorganization)
  • Assignor: Hitachi Consumer Electronics Co., Ltd.
  • Assignee: Hitachi Maxell, Ltd.
  • Correspondent: not retrievable
  • Context: Second intra-group transfer moving the consumer-electronics IP into Hitachi Maxell — again an internal reorg, not a transfer to an asserter.

• 2017 (corporate event; not confirmed as a separately recorded assignment for this patent) — Reel/frame not confirmed for '218 (family-level analogue: Reel 045142/0208 for "Hitachi Maxell, Ltd. → Maxell, Ltd.")

  • Conveyance: Change of Name / re-organization (Hitachi Maxell, Ltd. → Maxell, Ltd., via Maxell Holdings, Ltd.; family-level reels 058255/0579 and 058666/0407 appear in later 3.73(c) statements)
  • Assignor: Hitachi Maxell, Ltd. / Maxell Holdings, Ltd.
  • Assignee: Maxell, Ltd. (current assignee)
  • Correspondent: a "John R. ___" signature appears on a January 31, 2022 3.73(c) statement for a sibling Maxell patent — not confirmed as the recording correspondent and name incomplete; treat as an unverified lead only.
  • Context: Name change and holding-company collapse; assignee identity changes, not ownership economics.

• 2016-04-18 — anticipated expiration (no assignment; term ended).

  • Context: The patent expired roughly 20 years after its 1996-04-18 US filing, i.e., before the 2018–2019 Maxell assertion campaigns against ZTE/Apple.

If the Assignment Center shows no further records beyond the above for US 5,974,218, that is itself meaningful: there is no post-Maxell transfer of this patent to a third party.

Timeline diagram

timeline
    title Ownership of US 5974218
    1995 : Japanese priority filing
    1996 : US application filed by Hitachi Ltd
    1999 : Patent issued to Hitachi Ltd
    2009 : Hitachi transfers IP to Hitachi Consumer Electronics
    2013 : Recorded transfer to Hitachi Consumer Electronics
    2014 : Assigned to Hitachi Maxell Ltd
    2016 : Patent term expires
    2017 : Hitachi Maxell renamed Maxell Ltd

(The 2009/2013 pair reflects execution vs. recordation; the diagram places them in their respective years. The 2013 entry is the recorded event dated 2013-06-12 in the Google Patents legal events.)

NPE / troll-pattern signals

1. Shell-entity transfer — not present. Both post-issuance transfers move the patent between named Japanese operating corporations (Hitachi, Ltd. → Hitachi Consumer Electronics Co., Ltd. → Hitachi Maxell, Ltd.), all with real product businesses and Tokyo-area addresses. No "IP/Holdings/Ventures" LLC, no registered-agent service address, no Delaware/Texas single-purpose entity appears. (Events: 2013-06-12 and 2014-09-08.)

2. Known asserter in the chain — not present (but adjacent behavior noted). Neither current nor prior assignee matches the named public NPE lists (Acacia, Marathon, IV, IPNav, Wi-LAN/Conversant, Vringo, Pendrell, etc.). Maxell, Ltd. is an operating manufacturer that licenses and litigates aggressively (Maxell v. Apple 5:19-cv-00036; Maxell v. ZTE 5:18-cv-00034), and IAM (14 Nov 2017) reported Maxell striking "deals with Fujifilm and an NPE," suggesting a patent-monetization posture. That makes Maxell PAE-adjacent in style, but it is not on a recognized NPE registry, and no record shows this specific patent was asserted (it expired 2016-04-18).

3. Repeat correspondent across the chain — unclear. I could not retrieve the correspondent of record for any of the three assignment events on this patent from the accessible sources. The only attorney-adjacent artifact found is an incomplete "John R. ___" signature on a 2022 3.73(c) statement for a sibling Maxell patent. One appearance is not a finding, and this is not even confirmed to be a recording correspondent — so I decline to call it recurrence.

4. Cascading transfers — not present. Two transfers (2009/2013 and 2013/2014) span roughly five years, not <24 months, and both are intra-group Hitachi reorganizations rather than a chain of unrelated LLCs sharing principals or a correspondent address. No common-principal shell chain.

5. Pre-litigation transfer — not present. The nearest Maxell assertions post-date this patent's 2016-04-18 expiration; the 2013/2014 transfers precede the first relevant suits by 3–5 years. Nothing is dated within 6 months of an infringement filing naming this patent (and I found no filing naming it at all).

6. Bankruptcy fire-sale — not present. No Hitachi or Maxell bankruptcy; both are solvent operating groups. Compare the Kodak/Nortel/Polaroid pattern — absent here.

7. Privateering — not present. No evidence Hitachi (or Maxell) transferred this patent to a third-party NPE to assert against competitors. The chain stays inside the Hitachi/Maxell corporate family throughout. (The IAM-reported "NPE deal" concerns Maxell's outbound licensing activity on other patents, not a transfer of '218 to an asserter.)

8. Defensive aggregator — not present. The chain does not terminate at RPX, AST, LOT, Unified Patents, or OIN. It terminates at Maxell, Ltd., an operating manufacturer.

Verdict

Operating-company assertion.

The chain runs straight through named operating manufacturers — Hitachi, Ltd. → Hitachi Consumer Electronics Co., Ltd. (executed 2009 / recorded 2013-06-12) → Hitachi Maxell, Ltd. (executed 2013 / recorded 2014-09-08) → Maxell, Ltd. (2017 name change) — with no shell LLC, no NPE in the chain, no bankruptcy sale, and no defensive-aggregator terminus. Maxell, Ltd., the current assignee, is a real manufacturer that ships products and sues actual competitors (Apple, ZTE), which is the operating-company-assertion profile. Qualification: this particular patent expired on 2016-04-18, before Maxell's assertion campaigns, and I found no pleading asserting it — so the NPE signals are all negative, and the practical character of this chain is internal corporate reorganization, not monetization. The main data gap is the missing reel/frame and correspondent of record, which should be pulled directly from the Assignment Center to complete the record.

Verify at: USPTO Assignment Center search for patent 5974218 — https://assignmentcenter.uspto.gov/ (legacy interface: https://assignment.uspto.gov/patent/index.html) — searching by patent number will return the reel/frame, correspondent, and execution/recordation dates that the Google Patents-derived events above do not expose.

I'll research the patent citations for US 5,974,218, focusing on prior-art references cited during prosecution.

I have the front-page "References Cited" list. Now let me gather details on each cited reference.

Prior Art Analysis — U.S. Patent No. 5,974,218

Patent: U.S. 5,974,218 — "Method and apparatus for making a digest picture"
Inventors: Akio Nagasaka; Takafumi Miyatake; Yoshikazu Amano; Shigeru Hirahata
Assignee: Hitachi, Ltd. (now Maxell, Ltd.)
Filed: Apr. 18, 1996 · Priority: Apr. 21, 1995 · Granted: Oct. 26, 1999
Source: https://patents.google.com/patent/[US5974218A](/patent/US5974218A)/en · PDF front page: https://patentimages.storage.googleapis.com/bc/59/b1/415d19c5f5b554/US5974218.pdf

Scope and method note

"Each patent citation" for this patent means the references listed on the face of the patent under [56] References Cited (the documents the examiner/attorney cited against this application). I retrieved that list directly from the granted front page and the Justia mirror (https://patents.justia.com/patent/5974218). The list consists of nine U.S. patents and one Japanese laid-open publication:

Important verification caveat: I confirmed titles/contents directly for references 1, 2, 3, 9, and 10 (and I recognize 2 and 9 from the patent's own specification). For references 4, 5, 6, 7, and 8 I have only the front-page listing (number, patentee surname, date, and where shown, class) and could not independently re-verify each full title before my search budget was exhausted. I flag each such item below rather than assert a title I cannot ground. Where I give a probable identification, I label it as such.

The claim set (for the §102 mapping): independent claim 1 (digest-making apparatus: interface → frame converter → shot-transition detector → storage → display-control) and independent claim 8 (reservation-recording digest apparatus: reservation interface means → arithmetic processing means → timer means → time-zone display means with a display cap). Dependent claims of interest: 2–7 (claim 3 = time-zone display; 4–5 = display cap/thinning; 6–7 = pick-a-thumbnail-to-start-playback) and 9–15 (11 = shot-representative list; 12 = fetch-time recording; 13 = accompanying sound; 14–15 = time-indexed array/ thinning).

Reference-by-reference analysis

1. US 4,873,584 — Hashimoto — issued Oct. 10, 1989

Title: "Computer control for VCR including display of record playback listing and playback order selection" (verified — https://patents.google.com/patent/US4873584).
Description: A personal-computer-controlled VCR. It stores a one-week TV program schedule, automatically controls the VCR to record programs by channel/time, tracks tape-counter start/end positions per program, and presents a display of the recorded-program listing from which the user selects a playback order.
Relevance / §102: Directed to the reservation-record and listing/selection problem (this patent's stated background and claim 8's "interface means for fetching information of a time period and a television channel set previously"). It does not disclose converting a program's frames, detecting inter-shot transitions, or generating a digest of shot-representative pictures. Accordingly it is at most §102 background art to the interface/timer concept of claim 8, and only if one read claim 8 without the arithmetic-processing/digest-generation limitations — it cannot anticipate claim 8 as a whole. No effective §§102(a)/(b) date problem: issued 1989, well before the Apr. 1995 priority.

2. US 5,083,860 — Miyatake, Yoshizawa, Ueda — issued Jan. 28, 1992 (filed Mar. 11, 1991, Ser. No. 07/667,647)

Title: "Method for detecting change points in motion picture images" (verified — https://patents.google.com/patent/US5083860).
Description: The color-histogram cut-detection method: input frames in time series, compute a per-frame feature quantity including a color histogram, compute a correlation coefficient vs. the immediately preceding frame, compute a change rate of that correlation coefficient, and declare a cut/change point when the change rate exceeds an allowable value. It outputs the time code of the change point and a compressed image of the change point as index information.
Relevance / §102: This is the substantive core of the digest maker's shot-detection step (the patent's own FIG. 4/step 404–408, and its "CROSS REFERENCE" paragraph expressly cites this patent and JP-A-2-230930). It maps closely onto claim 1's "detecting unit for fetching the frame-based picture signal and for detecting… those frames which correspond to the inter-shot transitions," and onto claims 1, 2 (frame-based detection + time-of-fetch relation). It is by a common inventor (Miyatake) and same assignee. It does not disclose generating in parallel with recording, the time-zone display, or the reproduce-from-selected-thumbnail control. This is, in my assessment, the single most relevant cited reference for the shot-detection limitation.

3. US 5,157,511 — Kawai et al. — issued Oct. 20, 1992

Title: "Image control apparatus for providing an index number to a video reproducer to cause the reproducer to search for and to reproduce a preselected still image" (verified — https://patents.google.com/patent/US5157511).
Description: A controller for a laser-disc player that selects a number of still frames from a motion picture, stores each selected still frame together with its index number, displays the selected still images as secondary pictures alongside the primary picture, lets the user choose one (e.g., by cursor/pointing device), and copies that index number to the reproducer so the reproducer searches for and reproduces the chosen still image.
Relevance / §102: Directly relevant to the list-of-representative-pictures → user selects one → playback starts from that position aspect, i.e., claims 1, 6, and 7. Notably, claim 6's "means for starting reproduction… from a position indicated by a time point at which said given shot-representative picture… was fetched" is very close to Kawai's index-number hand-back. Kawai nevertheless does not detect inter-shot transitions automatically (still images are selected), does not record in parallel, and does not use time zones. So it is strong §102/§103 art against the selection/playback dependent claims, but does not anticipate independent claim 1 in full.

4. US 5,450,210 — Yoo — issued Sep. 12, 1995

(Unverified title.) The printed front page lists only "5,450,210 9/1995 Yoo" with no title or class in the record I retrieved. Given its placement in this citation list, it is almost certainly a video-recording/playback or on-screen-index reference, but I will not assert a title I could not confirm. §102: Can only be assessed against claims 1/8 on its face; treat as a §103 secondary reference unless its full text is pulled. I recommend retrieving the document directly before relying on it.

5. US 5,459,830 — Ohba et al. — issued Oct. 17, 1995 (class 345/473)

(Unverified title; class 345/473 = computer graphics/animation display generation.) The class suggests an image-compositing/display-generation reference — plausibly relevant to the display-control means of claim 1 or the display means of claim 8, but not to shot detection or parallel recording. §102: At most a §103 secondary/background reference. Flag: title and content not verified.

6. US 5,479,265 — Kim et al. — issued Dec. 26, 1995 (class 386/124)

(Probable, not confirmed: a scene-change / cut-detection method for digital video using frame-histogram differences — the class and patentee are consistent with that family, but I could not verify the title.) If confirmed, it is a second shot-transition-detection reference competing with US 5,083,860 for claim 1's detection limitation. §102: Potentially cumulative art on the detection step; would need its full text to state an anticipation position.

7. US 5,546,191 — Hibi et al. — issued Aug. 13, 1996

(Unverified title.) Issued after this application's Apr. 18, 1996 filing but with a filing date that would place it in the pre-AIA §102(e) window depending on its actual filing date; because the front page does not give a filing date for it in the record I retrieved, I cannot fix its §102 date. Flag for follow-up.

8. US 5,576,950 — Tonomura et al. — issued Nov. 19, 1996 (class 386/121)

(Probable, not confirmed: a video indexing/summary or video-handling method — Tonomura is a known author in video browsing/structuring; class 386/121 is video indexing.) If confirmed, it is another candidate reference against claim 1's digest-generation concept. Flag: title/content not verified.

9. US 5,818,439 — Nagasaka et al. — issued Oct. 6, 1998 (class 345/327)

Title: "Video viewing assisting method and a video playback system therefor" (verified; identified in the '218 specification's CROSS REFERENCE paragraph as Ser. No. 08/601,363, filed Feb. 16, 1996, based on JP 7-30418, and stated to be commonly assigned and to share inventors — https://patents.google.com/patent/US5974218A/en).
Description: A video terminal storing an interrupted playback position and generating representative/digest images (icon or digest list) of the program so the user can resume.
Relevance / §102: Since its Feb. 16, 1996 filing precedes this application's Apr. 18, 1996 filing and naming overlaps (Nagasaka), it is a candidate pre-AIA §102(e) reference for the digest-list and resume-from-position concepts (claims 1, 6, 7, 11). Note the applicant flagged it as commonly owned, so §103(c)-type common-ownership/terminal-disclaimer considerations could apply — a point worth raising. (Corroborated in EP 1310086 B1 background text: "US-A-5 818 439 discloses a video terminal device… video digest making program… list display based on reduced icons or a digest image.")

10. JP 3-35431 — published Feb. 1991

Description (verified from the '218 specification): A disk player that, prior to normal playback, alternately repeats a fast-feed/scan and a normal reproduction at a predetermined time interval regardless of recorded content, starting from the record-start position, thereby outputting picture signals intermittently.
Relevance / §102: This is the closest conceptual prior art to automatic "show me a preview" behavior and is expressly discussed in the Background. The patent distinguishes it on two grounds: (i) the intermittent reproductions are tied to a fixed time interval, so the scene of interest is not necessarily displayed; (ii) each retrieved picture is shown full-screen rather than as a condensed list, so the whole content cannot be seized at once. Because claim 1 requires shot-transition-based representative pictures arranged as a digest list, JP 3-35431 does not disclose the "inter-shot transition" detecting means or the list display, and so does not anticipate claim 1 — but it is the naturally strongest §103 starting reference for the "make a compact preview of a recorded program" motivation.

Overall anticipation (§102) assessment

• No single cited reference appears to disclose every element of independent claim 1 or claim 8. The novelty of the '218 claims resides in the combination: (a) generating the digest in parallel with recording by (b) detecting inter-shot transitions from frame data and storing shot-representative pictures with fetch times, and (c) displaying them grouped into time zones with a display cap — plus (d) using a selected thumbnail to control reproduction. The cited art splits these across different references:
  • shot-transition detection → US 5,083,860 (and possibly US 5,479,265);
  • listed representative stills + index-number-driven playback → US 5,157,511;
  • digest list + resume position → US 5,818,439;
  • intermittent preview of a recorded program → JP 3-35431;
  • reservation interface/timer → US 4,873,584.
• Strongest §102 candidates (claim-specific, not the whole patent):
  • US 5,083,860 → claims 1, 2 (detection/time-of-fetch aspects).
  • US 5,157,511 → claims 1, 6, 7 (list → select → reproduce-from-position).
  • US 5,818,439 → claims 1, 6, 7, 11 (subject to its §102(e) status and common-ownership/§103(c) considerations).
• Likely §103 combination, if these were re-litigated: US 5,083,860 + JP 3-35431, with US 5,157,511 or US 5,818,439 added for the selection/playback and time-zone features. That is a plausible obviousness theory, not §102 anticipation.
• Claims 3–5 and 14–15 (time-zone grouping / thinning) and claim 13 (accompanying sound) do not appear to be met by any single cited reference; these are the claims with the weakest prior-art exposure among those cited.
• References 4, 5, 6, 7, 8 need full-text retrieval before any §102 assertion can be made; I am not asserting titles or holdings for those beyond the face-of-patent data.

Caveats and recommended follow-up

1. Verified vs. unverified: Items 1, 2, 3, 9, 10 are grounded in retrieved text/URLs. Items 4, 5, 6, 7, 8 are given only as listed on the front page; their titles/holdings are not verified here. Do not quote a title for those five without pulling the documents.
2. §102 dates: For the post-1996-issued references (US 5,546,191; US 5,576,950; US 5,818,439) the controlling date is the filing date, not the grant date, under pre-AIA §102(e). I have only US 5,818,439's filing date (Feb. 16, 1996) confirmed; confirm the others.
3. This list is the cites on the patent, i.e., what the examiner/applicant placed of record. It is not necessarily the best prior art — e.g., the same-assignee/related work and Japanese applications from Hitachi's video-indexing program may include closer art not on this face list. Any invalidity/FTO study should run a separate prior-art search, not just read [56].
4. No connection to the litigation discussion: none of the references above ties to the Maxell/Huawei/ZTE campaigns raised in the earlier litigation section; that stays a negative finding.

If you want, I can re-run the targeted lookups for references 4–8 (US 5,450,210; US 5,459,830; US 5,479,265; US 5,546,191; US 5,576,950) to firm up their titles, filing dates, and §102 dates, which are the only gaps in the mapping above.

I'll analyze obviousness for US 5,974,218. First, let me ground the prior-art references cited on the patent page and identify the relevant art.

Let me pull the cited references list and the European counterpart (which describes shot-representative lists as book indices) to ground the § 103 combinations.

Obviousness Analysis — U.S. Patent No. 5,974,218 under 35 U.S.C. § 103

Scope note and grounding. This analysis builds on the two prior sections (bibliographic/technical summary and litigation summary) and does not repeat them. Per the instruction to use the prior-art material on the patent's page, I treat the citation set appearing in the patent's own "Cross Reference" and background sections — U.S. 5,083,860 / JP-A-2-230930 (JP 4-111181 / JP 2863818 B2), U.S. Ser. No. 08/601,363 (now U.S. 5,818,439), and JP-A-3-35431 — as the prior-art record, supplemented by the admitted "analogous art" (newspaper TV-program columns) and the admitted state of VTR timer-recording. My four follow-up searches were cut off by a tool/step limit, so this is a documentary analysis, not a substitute for the prosecution file history or a formal novelty/obviousness search.

Two corrections/updates to the earlier sections (flagged per operating rules):

1. The earlier "Patent summary" listed the claim set as claims 1–15 and flagged the count as uncertain because retrievable text was truncated mid-claim-15. The SumoBrain full-text page now retrieved (https://SumoBrain.com/patents/us/Method-apparatus-making-digest-picture/5974218.html) shows a claim 16 ("A digest making apparatus according to claim 11, wherein upon displaying of the digest information, the shot-representative pictures belonging to a predetermined temporal period of said television program are excluded from the objects for display"). The claim set is therefore claims 1–16, with independent claims 1 and 8.
2. Claim 1's preamble — which the earlier section could not recover verbatim — is constrained by claim 2's reference: "information of said digest list picture includes header information for identifying discriminatively a relevant program recorded by said recording means, shot-representative picture information indicating said inter-shot transitions, and information of time points at which said shot-representative picture information is fetched." So claim 1 recites a digest making apparatus, recording means recording a received TV signal, a digest list picture of shot-representative pictures at inter-shot transitions, and display control means. (I still cannot quote claim 1's preamble character-for-character; I am not asserting exact wording.)

1. The Graham framework

Obviousness asks whether the claimed subject matter as a whole would have been obvious to a person having ordinary skill in the art (PHOSITA) at the time the invention was made, in view of (i) the scope and content of the prior art, (ii) differences between the prior art and the claims, (iii) the PHOSITA's level of ordinary skill, and (iv) secondary considerations. Graham v. John Deere Co., 383 U.S. 1 (1966); KSR Int'l Co. v. Teleflex Inc., 550 U.S. 398 (2007).

Effective filing / critical date. Application 08/634,354 filed April 18, 1996; earliest priority April 21, 1995 (JP). Under pre-AIA § 102(b), any printed publication or patent dated more than one year before the U.S. filing (i.e., before April 18, 1995) is a statutory bar — with the practical caveat that the April 21, 1995 JP priority may be relied on for § 102(a)/(e) purposes. The primary references below comfortably antedate both dates.

PHOSITA level (proposed). A worker with a bachelor's degree in electrical engineering or computer science and roughly 2–4 years' experience in digital video/image processing, or an equivalent combination, familiar with (a) frame-based video signal handling and analog-to-digital video capture, (b) shot/cut-change detection via histogram or block feature differences, (c) video indexing/browsing using representative frames, and (d) consumer VCR timer ("programmed") recording and on-screen display menus. This is a routine-to-moderately-sophisticated software/CE engineering skill set, not a research-level one.

Secondary considerations. I found no evidence of nexus-qualifying secondary considerations (no licensing/settlement record tied to these claims, no litigation identified in the prior section, no documented commercial-success or long-felt-need evidence). The '218 patent's listed status is Expired – Lifetime (April 18, 2016), and the prior litigation section found no case asserting US 5,974,218. I therefore analyze the prima facie case on references alone, and note this evidentiary gap explicitly rather than assuming secondary considerations.

Terminology caveat. The strict operating rule requires literal interpretation of identifiers. JP-A-2-230930, JP 4-111181, JP 2863818 B2, EP 0 472 806 A2, and U.S. 5,083,860 are the same Hitachi/Miyatake family as confirmed by the sources retrieved (JP 2863818 B2 "動画像の変化点検出方法"; EP0472806A2; US 5,083,860; the Baidu excerpt listing 発明人 宮武孝文/吉沢聡/上田博唯, 出願番号 JP特願平2-230930, 公開号 JP第2863818号B2). I treat them as one reference family, not as distinct prior art.

2. The prior art and what it discloses

Reference A — U.S. 5,083,860 (Hitachi; issued Jan. 28, 1992) and its JP/EP family JP-A-2-230930 / JP 4-111181 / JP 2863818 B2 / EP 0 472 806 A2

The '860 patent explicitly discloses the entire shot-detection and representative-frame-storage core of the '218 patent's digest-making program (FIGS. 4/6 flow):

• Inputting motion pictures frame-by-frame in time series; computing a feature quantity including a color histogram per frame (the same "R-, G-, B-color values … degenerated to 64 colors / frequency array H_n(i), i = 0…63" approach recited in the '218 specification).
• Computing a correlation coefficient between a frame's feature quantity and the immediately preceding frame's, and a change rate relative to a past frame; declaring a change point between cuts when the change rate exceeds an allowable value. US 5,083,860 abstract and description.
• Storing the change-point image as compressed "index information" of the cut — including outputting "a time code identifying the determined frame and a picture image of a determined change point between cuts … as index information of that motion picture image cut" (EP0472806A2). The '860 patent stores "up to 100 compressed images … as index images" in main memory and overflows to disk. This maps onto the '218 claim-6/claim-12 limitations (representative picture + its fetch time) and claim-2 (header + representative picture info + fetch-time info).
• Expressly states its purpose is browsing: the index images and time codes "can be effectively used as browsing information for automatically searching heads."

Critically, the EP 0 729 117 B1 background confirms that the same JP 4-111181 family discloses the "list of images each representing a shot … used like indices of a book" and that this "allows one to grasp the contents of a video at a glance using the list and to locate a desired scene." That is, Reference A already teaches the "digest list picture" concept, the "shot-representative pictures of individual scenes in the form of a list" (claims 11/14), and the purpose of locating a desired scene (claims 6/7).

What A does not squarely show: a grid spatially indexed by a clock time (as opposed to a mere ordered list), the cap-and-select thinning of representative pictures within a time slot, and integration with a reservation timer. Those are addressed by the secondary references below.

Reference B — JP-A-3-35431 (disk player; intermittent fast-feed/normal reproduction)

Cited in the '218 background. Discloses outputting a picture signal intermittently by alternating fast-feed scanning and normal reproduction at a predetermined time interval, generating representative pictures tied to time intervals rather than content. The '218 specification criticizes B for "locations … specified in terms of the predetermined time interval" — i.e., B is time-interval-indexed, which is precisely the spatial organizing principle of the '218 time-zone display (claim 1's "time zone … indexed by a time point"; claim 3's "predetermined width"; claim 14's "field indexed with a time point").

Reference C — Admitted analogous art: newspaper/print TV-program columns

The '218 specification itself concedes that displaying time points in a vertical column "conforms with a layout of a television program column in newspaper, magazines or the like … known universally at present" and provides the advantage that "the content of the digest list picture can easily be understood because the format thereof bears similarity … to those in newspapers." This is a binding admission that the time-indexed column layout (FIGS. 7, 11) was known and conventional.

Reference D — Admitted state of the art: VCR programmed/timer recording

The '218 background and claim-8/9/10 discussion concede that "many" VTRs are "equipped with a function for recording a television program by programming the recording start and end times in advance" (the "programmed recording function"), and that timer-controlled power-on/power-off with lead/lag offsets is routine. Claim 8's "interface means for fetching … time period and … channel set previously for reservation," "timer means," and claims 9/10's power-on/power-off time spans are thus directed to admitted, well-known subject matter.

Reference E — U.S. 5,818,439 / Ser. No. 08/601,363 (Hitachi) — with a timing caveat

Expressly incorporated by reference by the '218 patent and cited in EP 1 310 086 B1's background. The related Hitachi "image retrieving" family (US 2002/0012521) describes a "window … for displaying a list of typical frame images", clicking a typical frame to select a scene, and "the frame number at the top of a scene is sent to the video reproducing apparatus and the playback is started from the scene," suspending at the scene's end. That maps onto the '218 reproduction-control limitations (claims 6/7) and onto the "select a shot-representative picture → start reproduction from its position" interface.

Timing caveat (important): '439 was filed Feb. 16, 1996 and issued Oct. 6, 1998; its JP priority (JP 7-30418, Feb. 20, 1995) would publish ~18 months later, i.e., after the '218 April 21, 1995 priority. As a U.S. patent it is therefore at best § 102(e) art, and because it is commonly owned by Hitachi with the '218 patent, pre-AIA § 103(c) could disqualify it from the obviousness combination. I therefore do not rely on Reference E as § 103 art; where the reproduction-control features matter I ground them in Reference A (JP 4-111181's express "locate a desired scene" purpose and '860's "searching heads") and in the admitted conventional VCR reproduction control. Reference E is cited only as corroborating context.

3. Claim-by-claim mapping

4. Specific § 103 combinations and the motivation to combine

Combination 1 (core digest: claims 1, 2, 11, 12, 14)

A (U.S. 5,083,860 / JP 4-111181 family) in view of B (JP-A-3-35431) and the admitted TV-column art (C).

A supplies every element of the content-generation side of claim 1 — frame-based digitization, color-histogram shot-change detection, a set of stored representative pictures at the transitions (index images), and their fetch times — and expressly frames the result as a browsable list of shot images ("like indices of a book … grasp the contents … at a glance"). B supplies the time-index interval organizing principle for presenting such pictures. C supplies the time-indexed column layout as an admitted, universally known convention.

Motivation. All three references are in the same field (indexing/browsing recorded video), address the same problem the '218 patent identifies (letting a user comprehend a recorded program quickly without linear playback), and produce predictable, expected results when combined. The '218 applicant plainly regarded these techniques as complementary — the specification itself cites B as the state it improves upon and adopts C's layout "because the format thereof bears similarity … to … newspapers." KSR expressly sanctions combining known elements "according to known methods … to yield predictable results," and the time-indexed presentation is exactly that.

Combination 2 (cap / selection / exclusion: claims 3, 4, 5, 15, 16)

Combination 1 in view of routine display-design considerations and B.

A fixed display area can present only a bounded number of thumbnails. Selecting a subset (thinning) when a time slot is over-populated is an obvious matter of design choice — the '218 specification itself frames the cap as necessary because "an excessively large number … will present an obstacle to quick grasp." B shows time-based deterministic selection of representative frames. Nothing unpredictable results; the scope of the claimed thinning (a stride, or nearest-time selection) is a mere optimization.

Combination 3 (reproduction control: claims 6, 7)

A in view of conventional VCR position control.

A states its index information is used for "automatically searching heads," and the JP 4-111181 family (per EP 1 310 086 / EP 0 729 117 background) already teaches that the list lets a user "locate a desired scene." Once a representative frame is stored with its time code, having a selection command seek the VTR to that time is the natural and anticipated use of the reference's own data structure — not an inventive leap.

Combination 4 (reservation/timer digest: claims 8, 9, 10)

A + D (admitted VTR programmed recording / timer art), optionally with B/C for the display.

Claim 8 is essentially A's digest generator placed inside the admitted VCR timer-recording paradigm: interface means for preset time/channel (D), timer start/end (D), and the time-zone display (B/C). Combining an automatic video-indexing function with an automatic timer-record function is an obvious aggregation of two known automations serving the same user need ("record while I'm away, then let me see what I got"). Claims 9/10's power-on/power-off lead/lag are admitted engineering routine in timer-driven devices.

The '218 patent itself corroborates the motivation: it repeatedly notes that reservation-recorded programs "may often be left … without being enjoyed," which is precisely the problem the digest is meant to solve — a stated, recognized motivation to marry the timer function to the digest function.

Combination 5 (audio around representative pictures: claim 13)

Combination 1 in view of the ubiquity of co-recorded audio. Storing a short audio snippet temporally near a representative frame is an obvious augmentation; the specification concedes the data cost is "much smaller" than motion-picture data, i.e., no technical hurdle existed.

5. Where the patent's non-obviousness case is strongest (candor check)

A rigorous analysis must identify the limitations least clearly met by the art above:

1. The "user-selectable" time-zone width in independent claims 1 and 8. The prior art (B, C) shows fixed/predetermined intervals. Note the internal claim nuance: claim 3 (dependent on claim 1) recites a "predetermined width" while claim 1 recites "width selected by a user" (claim 8 same). This drafting inconsistency is itself worth pressing in litigation/validity: if "user-selected" is read as merely "set beforehand by the user," claim 3 collapses into claim 1 and the independent claims add little over B/C; if read strictly, user-adjustability of a display interval is a thin, arguably obvious GUI choice.
2. The combination of concurrency (digest generated in parallel with recording in real time) with the capped, time-indexed grid. The strongest inventive story is the concurrent, real-time digest built during the recording pass. But the '860 reference already contemplates on-the-fly change-point detection and index-image storage, and the patent concedes no machine had done this specific thing — a "no prior apparatus" argument that is weak under § 103, where the question is what the prior art teaches or suggests, not whether anyone had assembled the exact product before.
3. Reference-E timing problem (noted above) means the reproduction-control claims (6/7) should be attacked via A and admitted VCR control, not the commonly-owned '439 — otherwise § 103(c) may knock out the most on-point secondary reference.

None of these is a convincing teaching-away or unexpected-result argument, and I found no secondary-considerations record.

6. Bottom line

On the available (patent-page) prior-art record, claims 1–16 of US 5,974,218 appear vulnerable under § 103 as a combination of:

• U.S. 5,083,860 / JP-A-2-230930 (JP 4-111181 / JP 2863818 B2 / EP 0 472 806 A2) — frame-based color-histogram shot-change detection, storage of change-point "index images" with time codes, and the express list-of-shot-images-as-book-indices browsing concept; in view of
• JP-A-3-35431 — time-interval-indexed intermittent presentation of representative pictures; and
• the admitted analogous art (newspaper TV-program column layout) and admitted VTR programmed/timer recording, with the cap/selection/thinning limitations supplied by routine display-design expedients.

The recurring motivation is uniform: same field (video indexing/browsing), same problem (comprehend a recorded program quickly), predictable combination of known elements, and the applicant's own admissions and cross-references tying the references together.

Confidence: High on the content and identity of References A/B/C and on the claim mapping; medium-high on the overall § 103 conclusion, because it rests on (i) a prima facie case without a prosecution-history check, (ii) claim 1's preamble that I could not quote verbatim, and (iii) my inability to complete the four follow-up prior-art searches due to the step limit. A definitive opinion requires the file wrapper (to see which references the examiner actually applied and whether § 103(c) removed the '439 family) and a full-text prior-art search for mid-1990s video-storyboard/thumbnail-grid art. This is a technical analyst's assessment, not legal advice.

Primary sources cited: US5974218A (https://patents.google.com/patent/US5974218/en); US5083860 (https://patents.google.com/patent/US5083860); EP0472806A2 (Hitachi '860 EP counterpart); EP0729117B1; JP2863818B2 (https://patents.google.com/patent/JP2863818B2/ja); SumoBrain full claim text (https://SumoBrain.com/patents/us/Method-apparatus-making-digest-picture/5974218.html); EP 1 310 086 B1 background; US 2002/0012521 (Hitachi image-retrieving family).