US 6577328

I'll verify current status via search, then summarize from the authoritative full text provided.

US Patent 6,577,328 — Verification Summary

Source grounding: Full text and bibliographic data from Google Patents (https://patents.google.com/patent/[US6577328](/patent/US6577328)/en, fetched 2026‑09‑24), cross‑checked against FreePatentsOnline (https://www.freepatentsonline.com/6577328.html) and Justia (https://patents.justia.com/patent/6577328).

Bibliographic data

Abstract (as published)

"To remotely control a virtual reality creature. A shared server provides a shared virtual reality space to client PCs. An AO server controls a growth parameter of the virtual life object existing in this shared virtual reality space to control autonomous behavior of the virtual life object. A communication server sends a message to a user of each of the client PCs who is the keeper of the virtual life object according to a status transition thereof through telephone or facsimile for example."

Plain-language overview of the independent claims

The patent has three independent claims (claims 1, 10, 11), covering the same subject matter in three statutory formats:

• Claim 1 — Program providing medium (software/computer-readable medium). A medium carrying a program for a "shared virtual space providing apparatus" that serves a shared virtual space to multiple networked clients and controls a virtual life object's autonomous behavior. The program (a) manages a communication control table registering the client user who is the "keeper," a notification method for messaging that keeper, and the keeper's contact address; and (b) sends a message to that contact address in response to a status transition of the virtual life object, using the registered notification method. In the claim text located on FreePatentsOnline/Justia, claim 1 further recites controlling a growth parameter control table classified into virtual life data and keeper data, and that the virtual life object "undergo[es] continuous autonomous transformation based on modifiable growth parameters comprising physical parameters and mental parameters," updated by a predetermined growth‑parameter equation on a timer event after a keeper‑initialized birth date.
• Claim 10 — Shared virtual space providing apparatus. The apparatus‑form counterpart: control means for a communication control table (keeper identity, notification method, contact address) plus sending means that dispatches the message to the keeper's registered contact address on a status transition of the virtual life object via the registered method.
• Claim 11 — Shared virtual space providing method. The method‑form counterpart: the steps of controlling such a communication control table and sending the message to the keeper's registered contact address per the virtual life object's status transition using the registered notification method.

Dependent claims elaborate the notification channels, e.g. electronic mail (claim 5), facsimile number with outgoing call (claim 7), access‑history‑triggered messages (claim 2), and message selection from among multiple message statements (claims 3–4). The specification describes notification methods encoded as: 0 = e‑mail, 1 = text‑to‑voice over analog telephone, 2 = PHS e‑mail via PIAFS, 3 = facsimile, 4 = pager (pager terminal 24). It also describes the reverse path (claim 8): interpreting an operation command returned with a caller ID through a simple communication apparatus (telephone/PHS, e.g. DTMF tones) and reflecting it onto the virtual life object's status transition.

Litigation / CAFC 2026 docket check

• I found no evidence of any CAFC docket, PTAB proceeding, or district‑court action involving 6,577,328 in my searches. Searches for litigation/docket activity returned unrelated matters (e.g., Medtronic v. NuVasive documents, PTAB PGR2021‑00041 regarding U.S. 10,625,149), not this patent. One search hit referenced "the '228 patent" in an ex parte reexamination document (ptacts.uspto.gov), but "'228" does not match the last three digits of 6577328 ('328'), so I do not attribute that document to this patent.
• Treat "no litigation/CAFC activity found" as a negative search result, not a positive confirmation of no litigation.

Uncertainties to flag (I will not fabricate)

1. Claim‑set discrepancy. The claim text on FreePatentsOnline and Justia shows claim 1 with additional "continuous autonomous transformation / growth parameter control table" limitations and claims 12–20 that do not appear in the abbreviated claim discussion in the Google Patents full text I was given. This pattern is consistent with a post‑grant ex parte reexamination certificate having amended claim 1 and added claims 12–20, but I could not confirm from the sources retrieved that a reexamination certificate (e.g., a "C1" document) exists for 6,577,328. The number of claims is shown as 20 in the FPO/Justia listings; I could not independently verify the as‑granted claim count. Do not rely on the amended text without pulling the official reexamination certificate from USPTO PatentCenter.
2. Current ownership. Google Patents lists "Z Intermediate Global Corp." as current assignee while recording a 2015 reassignment to LINE CORPORATION; Google disclaims accuracy of its assignee list. The authoritative ownership position should be confirmed via the USPTO Assignment database.
3. No CAFC 2026 docket entries were located; my searches did not surface a docket for this patent at all.

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

The initial searches surfaced no litigation. Let me run additional targeted queries to be thorough.

Litigation Search Report — U.S. Patent No. 6,577,328

Bottom line: I found no litigation involving U.S. Patent No. 6,577,328 ("6577328"). This is a negative search result, not a positive confirmation that no litigation exists. I could not access the Unified Patents litigation portal directly (the searches returned only paginated excerpts of other matters), so I cannot exclude the possibility of a case that is not indexed in the general web sources I reached.

Searches performed and what they returned

False-positive matches — explicitly excluded (do not attribute these to the '328 patent)

Per the instruction to interpret identifiers literally and return nothing for similar numbers, these hits are not U.S. 6,577,328:

1. JP 6577328 B2 — "Sealed structure of liquid injection part for lithium ion battery," assigned to Furukawa Battery Co. (古河電池株式会社), publication date 2019‑09‑18. A Japanese patent that merely shares the digits 6577328. (https://patents.google.com/patent/JP6577328B2/en ; https://ipforce.jp/patent-jp-B9-6577328)
2. Indian Army gazette entries — "Hav. Jamnel Singh (No. 6577328 now JC‑57057)," 1969. Personnel/service numbers, not patents.
3. Estonian land-survey coordinates ("X = 6577328.87") — geodetic data.
4. PTAB exhibits referencing "6577328" — e.g., PGR2021‑00041 (U.S. 10,625,149) and IPR2022‑00055 / IPR2020‑01708 (U.S. 7,756,507) disclose long lists of patent numbers and litigations; 6577328 appears only as incidental text, not as a patent-in-suit.

Note also the two "Sony Corporation" litigation threads that surfaced are for other Sony patents, and one (Sony v. ARRIS/Pace, D. Del. 1:15‑cv‑00288) has Sony as plaintiff asserting patents 6,084,643 / 6,097,676 / 6,467,093 / 7,733,295 / 8,032,919 — again not 6,577,328.

Case-by-case table

There are no cases to list. No plaintiff, defendant, jurisdiction, case number, filing date, or outcome can be reported for U.S. 6,577,328 because no litigation was located.

Why this is plausible (context, not proof)

• Google Patents records the patent as "Expired – Lifetime," adjusted expiration 2018‑07‑20, and the underlying application was filed 1998‑05‑26 with earliest priority 1997‑05‑28. Any U.S. patent with a 1997 priority date would have expired by the mid‑2010s, sharply limiting the window for assertion.
• The recorded assignment chain (Sony (1998) → LINE CORPORATION (recorded 2015‑08‑27); Google listing "Z Intermediate Global Corp." as a possibly-inaccurate current assignee) shows the asset was moved late in life but, based on my searches, never became the subject of a filed infringement action.
• Neither original assignee Sony Corporation nor 2015 transferee LINE Corporation appears in my results as having asserted this patent.

Caveats / limitations (stated explicitly, not fabricated)

1. Coverage gap. I could not load the Unified Patents litigation portal, PACER, or Docket Alarm case lists for this specific patent (search tool limits were reached). A PACER/Docket Alarm/Unified "patent litigation" query and the USPTO Patent Assignment record should be run to confirm the ownership and litigation status.
2. Claim-set discrepancy (carried over from the prior section). The earlier summary flagged that FreePatentsOnline/Justia show claim 1 with additional growth‑parameter limitations and claims 12–20 not present in the Google Patents full text — consistent with a possible post‑grant ex parte reexamination certificate, which I could not confirm. If such a certificate exists, it should be pulled from USPTO PatentCenter; it does not, however, change the litigation finding.
3. Date note. Your prompt states the current date is April 26, 2026; the working system date is 2026‑09‑30. My searches covered results available up to the latter. Any case filed after the index date of the sources I could reach would not be captured.
4. "No litigation found" ≠ "no litigation exists." Treat this as an unverified negative.

Recommendation to confirm: run a direct query on (a) USPTO Patent Assignment / PatentCenter for application 09/084,183, (b) PACER docket search for "6,577,328," and (c) Unified Patents and Docket Alarm patent‑specific litigation pages, using the exact string "6,577,328" and excluding JP 6577328 B2.

I'll verify the structured PTAB list against public sources before writing.

PTAB / AIA Trial Analysis — US 6,577,328 B2

Sources consulted: the structured "PTAB proceedings on file" block supplied with this prompt (USPTO Open Data Portal ingest — canonical), plus live web searches run 2026-09-30 targeting PTAB E2E/docket, Docket Alarm, FreePatentsOnline and general web for "6577328" + IPR/PGR/CBM, and for the recorded assignee "Z Intermediate Global Corp." No search returned a proceeding number, petition, institution decision, or FWD naming this patent.

Proceedings overview

Zero AIA trial proceedings are on file for US 6,577,328 — the USPTO ODP block returns no IPRs, no PGRs, and no CBMs, so the breakdown is 0 active / 0 claims invalidated / 0 claims sustained / 0 settled / 0 institution-denied, and I found no secondary source describing any proceeding either; the bottom-line defensive posture is not "hardened by surviving IPRs" (there is no hardening, because there was no attack) but something better for a defendant: the patent's recorded term expired on 2018-07-20, so a demand letter citing 6,577,328 today has no live infringement theory and, per § 286's six-year lookback, no recoverable past damages either — treat any assertion as a paper threat, not a litigation threat, and verify expiration from PatentCenter before you say so in writing.

No proceedings on file

There is no proceeding number to populate the per-proceeding template with, and I will not generate one. For completeness, the template fields would all be "n/a" for the same reason: no petitioner, no filing date, no panel, no grounds, no institution decision, no FWD, no settlement, no appeal.

This is a negative search result, not a positive confirmation. What I actually established:

1. The structured ODP block in this prompt states the API "returns no AIA trial proceedings for this patent as of the most recent ingest." That is the canonical list and I adopt it.
2. Live searches for the patent number paired with "IPR," "PGR," "CBM," "PTAB," and "petition" returned only unrelated matters — e.g., PGR2021-00041 (U.S. 10,625,149), CBM2014-00018 (U.S. 8,037,158, SAP America v. Pi-Net), and an NPE/Unified Patents appeal involving U.S. 7,373,655. None of those cite 6,577,328.
3. A search aimed at the recorded assignee "Z Intermediate Global Corp." returned no results at all — consistent with a shell/placeholder assignment entry rather than an entity that has asserted this patent.

Flagged contradiction/question carried over from the prior section

The previously generated Patent summary flagged that FreePatentsOnline/Justia show claims 12–20 and an amended-looking claim 1 that do not match the abbreviated claim discussion in the Google Patents full text — a pattern consistent with a post-grant ex parte reexamination certificate. That flag stands and is directly relevant here: an ex parte reexamination is conducted by the Central Reexamination Unit, not the PTAB, so it would not appear in the ODP "AIA trial proceedings" list. In other words, "0 PTAB proceedings" and "possibly a reexam certificate exists" are not in conflict — they are two different systems. I could not confirm or rule out a reexam certificate from the sources available, so the claim-set question must be resolved from USPTO PatentCenter/the official certificate, not from PTAB sources. (Note also the prior section's caution about a "'228 patent" document — that does not match 6577328's last three digits and should not be attributed to this patent.)

Strategic summary

Which claims are CANCELED vs. SUSTAINED vs. UNTESTED. Because no AIA trial ever issued a Final Written Decision, no claim of 6,577,328 has been canceled or held unpatentable through the PTAB. Every claim is UNTESTED at the PTAB — as-granted claims 1–11 (or the FPO/Justia-superseding set including claims 12–20, if a reexam certificate exists) carry no PTAB estoppel history, no PTAB claim-construction record, and no PTAB-verified validity. The prior section's uncertainty about the operative claim set therefore matters more than usual: there is no FWD to tell you which text governs, so the only reliable source is the official patent document/reexam certificate.

Estoppel landscape. § 315(e)(2) estoppel is a non-issue — there is no petitioner and no proceeding, so no person is estopped from raising any ground. Conversely, there is also no § 315(b) one-year bar clock running (that clock starts when a petitioner is served with a complaint), which means that if a defendant were served tomorrow, the full IPR toolbox (§ 102/§ 103 on patents and printed publications, plus § 112 arguments if a PGR-style posture were available) would theoretically be open. Practically, though, the § 1-year window is irrelevant if the patent is expired: an expired patent can still be the subject of an IPR, but the Board applies the Phillips claim-construction standard rather than the broadest reasonable interpretation (effective for petitions filed on or after 2018-11-13, per the Office's rule change) — and, more decisively, post-expiration challenges now face heavy discretionary-denial headwinds under the Office's 2025 interim processes, which expressly weigh "settled expectations, such as the length of time the claims have been in force." That factor is drawn directly from the Director-level decision in IPR2025-00408 (Patent 9,771,169 B2), In re AXA Power ApS v. Dabico Airport Solutions Inc., issued 2025-06-18 by Acting Director Coke Morgan Stewart, which denied institution based in part on the patent having been "in force almost eight years." (I saw this decision quoted in a Federal Circuit filing attachment rather than at PTAB E2E — treat the citation as reliable in substance but pull the paper directly before relying on it in a brief.) A patent in force for ~20 years and expired for ~8 would be an extreme candidate for that treatment, which is likely one reason it attracted no challengers in the first place: when a patent expires, the economic motive to invalidate it evaporates.

Pattern signals. No petitioner has ever filed even one IPR on this patent, let alone a repeat petitioner. No defensive aggregator (Unified Patents, RPX, etc.) appears anywhere in the chain — the assignment history recorded in the authoritative text runs Sony Corporation (recorded 1998-10-02) → LINE CORPORATION (recorded 2015-08-27), with Google's "current assignee" field showing "Z Intermediate Global Corp." (which Google itself disclaims as potentially inaccurate). There is no evidence of aggressive PTAB appeal practice by the patent owner, because there is no PTAB practice at all. The timing is worth noting for the record: the AIA trial regime opened 2012-09-16 and the patent expired 2018-07-20, so there was a ~5.8-year window in which an IPR against this patent was cheap, fast, and fully available — and it produced filing volume of exactly zero, which strongly suggests the patent was never asserted against a well-funded operating company in that window.

Recommended next steps

If you are a defendant or have received a demand letter citing 6,577,328:

• Lead with expiration, not with PTAB history. Google Patents records the status as "Expired – Lifetime" with an adjusted expiration of 2018-07-20 (filing 1998-05-26, priority 1997-05-28, issue 2003-06-10). Confirm by pulling the maintenance-fee and term-adjustment record from USPTO PatentCenter (https://patentcenter.uspto.gov/) and the fee history from the USPTO Patent Maintenance Fees storefront. If, as recorded, the term ended 2018-07-20, then (a) there is no ongoing infringement, and (b) § 286's six-year damages lookback from a 2026 filing reaches back only to 2020, which is after expiration — leaving no damages period at all. Say so in your response letter, but attribute the date to the record you actually verified.
• There is no FWD to link to or quote. I will not characterize one, because none exists. Do not let opposing counsel imply that earlier PTAB litigation narrowed this patent — it did not.
• Resolve the claim-set question before responding on the merits. Because the surviving-text issue flagged in the prior section (possible ex parte reexamination certificate producing amended claim 1 and added claims 12–20) is unresolved, and a reexam document would live in PatentCenter / the USPTO reexamination records (CRU) rather than in PTAB ODP, order the full file history plus any reexam certificate. This is a ~$30–$100 records request that eliminates the ambiguity.
• If you nonetheless want a validity belt-and-suspenders position, an IPR under 35 U.S.C. §§ 311–319 remains legally available against an expired patent, but expect a fight at the institution stage: cite the Phillips standard (petitions filed on/after 2018-11-13) and anticipate a discretionary-denial argument under the Office's 2025 interim processes weighing "settled expectations." Budget accordingly, and note that no estoppel currently binds anyone — § 315(e)(2) is dormant — so a later-filed challenge by a different party is not barred by anything that has happened to date.

If you are the patent owner:

• There is no IPR/PTAB precedent to point to as proof of validity, and no PTAB activity to distinguish. Your only realistic enforcement story would have to rest on pre-2018-07-20 conduct, which is time-barred for a suit filed now. Assume any assertion will draw an immediate expiration/time-bar response.

If you are monitoring for defensive purposes:

• Set a watch on PTAB E2E (https://ptab.uspto.gov/) and Docket Alarm's PTAB and district-court feeds for this patent number. Given expiry, the expected future value of that watch is low — but the watch will also catch any new ex parte reexamination or certificate activity, which is the one live uncertainty carried over from the prior section. The absence of any AIA trial is itself the signal: a patent that was never worth attacking was, in all likelihood, never worth asserting.

I'll search for the recorded assignment records for this patent before assembling the chain.

Let me run more targeted queries on the assignment chain and the entities.

I was unable to reach the USPTO Assignment Center record detail (reel/frame, correspondent, execution dates) with the tools available — searches surfaced no indexed Assignment Center or TSDR page for US 6,577,328. The search calls budget is now exhausted. Below I reconstruct what the record supports and mark precisely where the primary record could not be retrieved, rather than filling gaps with plausible-looking reel/frame numbers.

Inventors

Basis: Google Patents legal events for this patent record the 1998‑10‑02 assignment entry with "Assignors: HANAYA, HIROYUKI, MATSUDA, KOICHI" and assignee SONY CORPORATION — i.e., both inventors executed an assignment to Sony close to filing (application filed 1998‑05‑26; recordation 1998‑10‑02, ≈4 months later). Koichi Matsuda's name also appears in the specification itself as the translator of the cited VRML text ("Getting to Know VRML") and as co‑author of the cited bit magazine VRML articles, which is consistent with his being on Sony's VRML/"Community Place" development team at the time. I could not verify specific job titles, Sony business units, or whether either inventor left Sony within 12 months of filing — no employee‑movement data is in the assignment record, and I did not locate corroborating sources.

Unusual-pattern note (negative): There is no evidence of the pre‑fire‑sale signature here (all inventors departing the original assignee within 12 months). The inventors' rights were conveyed to the company at filing as a routine employment assignment, and the company held the patent for another ~17 years. This pattern is the opposite of a rapid inventor walk‑out.

Original assignee

Sony Corporation (Tokyo, JP) — named at issue (2003‑06‑10) and original assignee of record.

• Product embodying the claims: Yes — on the face of the specification. The patent's own text describes Sony's commercialized Community Place Browser / Community Place Bureau (registered trademark), a VRML 2.0 browser plus shared server, with a downloadable beta at http://vs.sony.co.jp. The claims (1, 10, 11) are directed to serving a shared virtual space to client apparatuses and controlling a virtual life object; Community Place Browser/Bureau is the commercial system the specification ties to that teaching. This is strong evidence of an operating‑company implementation at the relevant time.
• Primary line of business: Consumer electronics, media, and computer entertainment; pc.sony.co.jp/vs.sony.co.jp were Sony's PC and virtual‑society web properties referenced in the spec.
• Current status: Operating. Sony Corporation remains a going concern; it is no longer the owner of this patent (see timeline).

Assignment timeline

Important provenance limitation, stated up front: The only assignment evidence I was able to retrieve is Google Patents' "Legal Events" table (https://patents.google.com/patent/US6577328/en), plus the related cross‑references in the previously generated sections. Google Patents exposes the assignor, assignee, conveyance brief, and recording date, but not the reel/frame, the execution date, or the correspondent of record. The USPTO Assignment Center (https://assignmentcenter.uspto.gov/; legacy index at https://assignment.uspto.gov/patent/index.html) was not reachable/indexed in my searches, so I cannot supply the reel/frame or correspondent fields the task asks for. I am deliberately not guessing them.

Recorded assignments located (2):

• Execution date not stated in retrieved source / recorded 1998‑10‑02 — Reel not retrieved

  • Conveyance: ASSIGNMENT OF ASSIGNORS' INTEREST (SEE DOCUMENT FOR DETAILS) — i.e., ordinary assignment of the entire right, title and interest
  • Assignors: Hiroyuki Hanaya; Koichi Matsuda (joint inventors)
  • Assignee: Sony Corporation
  • Correspondent: not retrieved — verification required
  • Context: founding/employment assignment — inventors convey the application to their employer immediately post‑filing. Routine; no aggregation, securitization, or asserter involvement.

• Execution date not stated in retrieved source / recorded 2015‑08‑27 — Reel not retrieved

  • Conveyance: ASSIGNMENT OF ASSIGNORS' INTEREST (SEE DOCUMENT FOR DETAILS)
  • Assignor: Sony Corporation
  • Assignee: LINE CORPORATION
  • Correspondent: not retrieved — verification required
  • Context: third‑party acquisition — a portfolio‑style transfer from a large consumer‑electronics operating company to a large internet/messaging operating company. The transaction's scope (single patent vs. bulk portfolio) is not determinable from the record retrieved; note as context only that LINE's Tokyo/NY IPO followed in July 2016, which is consistent with pre‑IPO IP build‑up, but I have no document tying this transfer to that.

Not a recorded assignment (flagged so it is not double‑counted):

• 2023‑10‑01 — "LINE Corporation → Z Intermediate Global Corporation." Per Wikipedia (JA/ZH) coverage of the LY Corporation reorganization, LINE Corporation changed its corporate name to Z Intermediate Global Corporation effective 2023‑10‑01, with certain overseas shares, assets, rights and business moved to LY Corporation by absorption‑type company split (吸収分割). A pure change of name is not a transfer of title, but if recorded with USPTO it would appear as a Change of Name conveyance. I could not confirm whether any such recordation exists for this patent. This is the most likely explanation for Google Patents showing "Z Intermediate Global Corp." as current assignee while recording the 2015 assignee as "LINE CORPORATION."

Open discrepancy (carried forward and refined): The prior section flagged Google's "Z Intermediate Global Corp." current‑assignee field as potentially inaccurate. The Wikipedia material suggests the LINE corporate family split in 2021 into (a) a first‑generation LINE株式会社 → A Holdings and (b) a successor entity → LINE株式会社 (2nd gen) → Z Intermediate Global. Which legal entity actually holds this patent today therefore depends on whether title passed through the 2021 absorption‑type split. I could not resolve this and will not assert it. Verify in USPTO Patent Assignment / PatentCenter.

No further records found. There is no indication of any security agreement, license, release, correction, or third‑party transfer after 2015.

Timeline diagram

timeline
    title Ownership of US 6577328
    1997 : Priority filing in Japan
    1998 : US application filed by Sony
         : Inventors assign to Sony Corp
    2003 : Patent issued to Sony
    2015 : Assigned to LINE Corporation
    2018 : Patent reached expiry
    2023 : LINE renamed Z Intermediate Global

(The 2023 entry is a corporate renaming — not a recorded assignment; shown for chain continuity.)

NPE / troll-pattern signals

1. Shell-entity transfer — NOT PRESENT. The 2015 link runs Sony Corporation → LINE Corporation, both large, publicly visible operating companies with products in commerce (Sony: Community Place Browser/Bureau per the spec; LINE: the LINE messaging app). There is no "IP/Patents/Licensing/Holdings/Ventures" suffix on the 2015 assignee, no single‑purpose LLC, and no registered‑agent address in the record I retrieved. Caveat: the 2023 "Z Intermediate Global Corporation" name is an intermediate holding company designation, but it is a renaming of an operating group's entity, and I found no evidence it is a licensing‑only vehicle for this patent. Naming alone is not a finding.
2. Known asserter in the chain — NOT PRESENT. Neither Sony Corporation, LINE Corporation, nor Z Intermediate Global Corporation appears on the NPE rosters specified (Acacia, Marathon, Intellectual Ventures, IPNav, Wi‑LAN, Mosaid/Conversant, Vringo, Pendrell, Innovatio, MPHJ, Lumen View, Round Rock, Document Generation Corp, Spangenberg entities). Z Intermediate Global is an LY Corporation (Naver/SoftBank JV) intermediate holding company — an operating‑group affiliate. Caveat: I could not load RPX or Unified Patents asserter directories (tool limits), so this is a negative search result, not a verified absence.
3. Repeat correspondent across the chain — UNCLEAR (not assessable). The correspondent of record is not exposed in the sources I could reach for either entry (1998‑10‑02 or 2015‑08‑27). No determination can be made, and I will not name a firm. This is the single highest‑value field to pull next — with only two links set 17 years apart, recurrence is inherently unlikely, so low expected yield.
4. Cascading transfers — NOT PRESENT. Two recorded transfers spaced ~17 years (1998 → 2015), with the underlying filing 1998‑05‑26 and priority 1997‑05‑28. No chained LLC hops, no <24‑month clustering.
5. Pre‑litigation transfer — NOT PRESENT. No infringement suit naming this patent was located (per the prior litigation section), so no transfer sits within 6 months of a first suit. The 2015 transfer predates the patent's 2018‑07‑20 adjusted expiry by ~3 years.
6. Bankruptcy fire‑sale — NOT PRESENT. Neither Sony Corporation (1998 assignee/seller) nor LINE Corporation (2015 purchaser) was in Chapter 7/11 proceedings tied to this asset. No court‑ordered or estate sale record surfaced.
7. Privateering — NOT PRESENT / UNCLEAR. No SEC disclosure, Patent Progress, or EFF coverage was found indicating Sony transferred this patent to an NPE to assert against competitors on Sony's behalf. The transferee is a large operating group in a different market (messaging/games vs. consumer electronics), not an assertion vehicle.
8. Defensive aggregator — NOT PRESENT. The chain does not terminate at RPX, Allied Security Trust, LOT Network, Unified Patents, or Open Invention Network. It terminates inside an operating business group.

Verdict

Defensive / non-asserting — with an explicit rubric caveat.

On the operative criterion — assertion — the record is clean: the patent passed from one large operating company (Sony, 1998‑10‑02) to another (LINE Corporation, 2015‑08‑27), no infringement action naming US 6,577,328 was located, no NPE category from the checklist is supported by affirmative evidence, and the patent reached its 2018‑07‑20 adjusted expiration unasserted, i.e., it is neutralized. Caveat: this verdict option is defined in the rubric by termination at a defensive aggregator, which is not what happened here — so the more precise description is "large‑operating‑company‑held, never asserted, now expired," a category the five‑option rubric lacks. I did not select "Operating‑company assertion" because that requires an actual assertion against competitors, which is absent, and I did not select any NPE tier because the shell‑entity, known‑asserter, cascading‑transfer, and pre‑litigation‑transfer signals are all not present.

Reel/frame and correspondent are unretrieved in this analysis, so the two fields the task treats as the strongest tells (repeat correspondent; conveyance detail) remain open. Verify at:

• USPTO Assignment Center: https://assignmentcenter.uspto.gov/
• Legacy assignment search index: https://assignment.uspto.gov/patent/index.html
• Google Patents legal events (source used above): https://patents.google.com/patent/US6577328/en
• USPTO Patent Center (application 09/084,183) for the assignment abstract of title and any change‑of‑name record
• Query string to use: 6,577,328 and/or application 09/084,183 — exclude JP 6577328 B2 (Furukawa Battery, sealed structure for a lithium‑ion battery liquid injection part), which shares the digits but is unrelated.

I'll search for the patent's citation records on USPTO/Google Patents to identify the prior-art references cited against 6,577,328.

Let me pull the citation tables from the patent database pages directly.

I have the citation list from Justia and FPO. Let me pull the remaining full reference list and details on the key references.

I hit the tool-use limit before I could retrieve per-reference filing dates and titles for every entry, so the following is built strictly from what I did retrieve (Google Patents, Justia, FreePatentsOnline citation lists) plus clearly-labeled analyst inference. Where I could not verify a title/filing date, I say so rather than guess.

Prior-Art Analysis — U.S. Patent No. 6,577,328

1. Scope, sources, and exclusions

Patent under review (interpreted literally as "6577328"): US 6,577,328 B2, "Program providing medium and shared virtual space providing apparatus and method," Sony Corporation, appl. 09/084,183, filed 1998‑05‑26, JP priority 1997‑05‑28, granted 2003‑06‑10.

Sources used for the citation lists:

• Justia — https://patents.justia.com/patent/6577328 ("Referenced Cited")
• FreePatentsOnline — https://www.freepatentsonline.com/6577328.html
• Google Patents — https://patents.google.com/patent/US6577328/en (full text provided)

Literal-ID exclusions (per the strict rule, do NOT attribute these to 6,577,328): JP 6577328 B2 (Furukawa Battery, "Sealed structure of liquid injection part for lithium ion battery," 2019‑09‑18); Indian Army service number 6577328; Estonian survey coordinate 6577328.87.

2. Two critical methodological caveats before the tables

(a) "Cited" ≠ "anticipating." These are references the examiner considered. Being listed under "References Cited" means the examiner weighed them; it does not mean any reference meets the strict "single reference discloses every limitation" test of 35 U.S.C. § 102.

(b) Date floor of § 102. With a 1997‑05‑28 priority date (US filing 1998‑05‑26), the § 102(b) statutory-bar date is ~1997‑05‑26, and the § 102(a)/(e) critical date is ~1997‑05‑28. Consequently:

• Only references published on/before 1997‑05‑26 are § 102(a)/(b) art on their face (US 5,109,407; 5,393,070; 5,572,646; 5,586,257).
• Every reference granted 1997‑08‑19 or later can only be § 102(e) art, and only if its own US filing date predates 1997‑05‑28. I was not able to retrieve the underlying filing dates for each reference within the tool budget — those are flagged "verify."

Claim set of reference: independent claims 1 (program medium), 10 (apparatus), 11 (method); dependents 2–9 and (per the previously flagged claim-set discrepancy) likely 12–20. All three independents require the same core: a communication control table registering (i) the keeper, (ii) a notification method, (iii) the keeper's contact address, plus sending a message to that address on a status transition of the virtual life object using the registered method.

3. Cited U.S. Patent Documents (26 of the 27 shown on the face; the 27th is US 5,754,740 listed at the end)

4. Cited Foreign Patent Documents

5. Cited Non‑Patent Literature

(Note: the Justia listing shows the Damer item truncated as "Peopled Online Virtual Worlds: A New Home for…"; I could not confirm the full title within the tool budget.)

6. Findings — most relevant prior art and claim‑by‑claim § 102 assessment

6.1 Bottom line

No cited reference discloses every limitation of independent claims 1, 10, or 11. Each independent claim requires the combination of (i) a communication control table registering the keeper, a notification method, and the keeper's contact address, and (ii) sending a message to that address on a status transition of the virtual life object using the registered method. None of the 27 US patents, the 2 JP publications, or the 5 NPL items discloses that combination. The cited art is best characterized as background/§ 103 art and, for a few references, potentially anticipating narrow dependent‑claim concepts, not the independents.

6.2 Ranked most‑relevant references

1. US 5,966,526 (Yokoi, 1999‑10‑12) — virtual‑creature fostering simulation; closest to "virtual life object with a growth/status state." No shared server, keeper table, or messaging. → § 102(e) candidate (verify filing date).
2. US 5,572,646 (Kawai, 1996‑11‑05) / JP Hei 7‑160853 (Jun. 1995) — virtual‑creature growth‑state display. → true § 102(a)/(b) art, but for the growth‑display concept only.
3. US 5,956,038 (Rekimoto) + US 5,956,028 (Matsui) + US 5,926,179 (Matsuda) — shared 3D virtual‑space client/server systems. → § 102(e) art for the "shared virtual space" preamble.
4. US 5,802,296 (Morse, 1998‑09‑01) — network delivery of supervisory/notification control to users' displays. → § 102(e) art for the notification limb, but no virtual‑life trigger.
5. US 6,175,857 (Hachiya, 2001‑01‑16) — attached e‑mail processing. → § 102(e) art for the e‑mail notification dependent claim.
6. US 6,009,460 (Ohno, 1999‑12‑28) — self‑modifying avatars by category; US 6,141,019 (Roseborough, 2000‑10‑31) — creature animation/simulation. → § 102(e) art for appearance‑change dependent claims.
7. NPL — Chen et al. (Feb. 1997) and Damer et al. (1997) for populated VRML virtual worlds; Pesce (1995) and the Nikkei articles for background.

6.3 Claim‑level § 102 mapping (as far as the retrieved record supports)

7. Limitations and items to verify (stated explicitly)

1. Filing dates not retrieved. I could not retrieve the underlying US filing dates for the post‑1997 references, so their eligibility as § 102(e) art is flagged "verify" throughout. A proper § 102(e) analysis requires each reference's pre‑1997‑05‑28 US filing date from USPTO PatentCenter/Google Patents.
2. Titles unverified for 5,109,407 (Fujita), 5,393,070 (Best), 5,659,691 (Durward), 5,727,950 (Cook). I declined to guess.
3. Claim‑set discrepancy (carried forward). The earlier sections flagged that FreePatentsOnline/Justia show claim 1 with additional growth‑parameter limitations and claims 12–20, consistent with a possible post‑grant ex parte reexamination certificate (e.g., a "C1" document). If such a certificate exists, the § 102 mapping above must be re‑run against the amended claim 1 and any new claims; I could not confirm the certificate within the tool budget.
4. "Cited" ≠ "anticipating." These references were before the examiner; the Federal Circuit requires a single reference to disclose all limitations, arranged as in the claim, for § 102 novelty. On the retrieved record, none meets that bar for claims 1/10/11.
5. USPTO direct query not completed. My article‑level access was Google Patents, Justia, and FPO. A formal USPTO PatentCenter / "Patent Public Search" run on application 09/084,183 (and the reexamination record, if any) should be performed to confirm the as‑issued reference list and claim set.

Recommended confirmation steps: (a) USPTO Patent Public Search for appl. 09/084,183 to pull the official "References Cited" with each reference's US filing date; (b) confirm whether a reexamination certificate exists for 6,577,328; (c) verify the four unconfirmed titles and the truncated Damer citation.

I'll ground this analysis in the prior art of record. Note first: the material I received from the earlier steps contains a "Patent summary" and a "Litigation summary", but no section labeled "Prior Art" — so I cannot literally "use the results from the Prior Art section." I'll flag that gap and reconstruct the prior-art base from (a) the references cited in the authoritative specification text you provided and (b) live searches to verify dates/identifiers.

Good grounding. Let me verify the notification-side and networked-virtual-pet prior art for the combination analysis.

Obviousness Analysis — U.S. Patent No. 6,577,328 under 35 U.S.C. § 103

0. Scope caveat (must read first)

You instructed me to "use the results from the Prior Art section of this page." The materials I received contain only a "Patent summary" and a "Litigation summary" — there is no "Prior Art" section among the prior-generated sections. I will not pretend otherwise. Instead I reconstruct the prior-art base from two verifiable sources:

1. The references cited in the authoritative specification text you supplied (the patent's own "Description of Related Art"). Under MPEP 2129, an applicant's characterization of the background art is generally usable as admitted prior art, and several of these references are independently §102(a)/(b) art.
2. Live-verified references I searched and confirmed below (URLs given).

I flag the date discrepancy previously noted (prompt says 2026‑04‑26; system date 2026‑09‑30). It does not affect the §103 timeline, since all references and the patent's expiry (2018‑07‑20 per Google Patents) predate both dates.

1. Governing framework

• Graham v. John Deere factors: scope/content of prior art, differences, PHOSITA level, secondary considerations.
• KSR Int'l v. Teleflex (2007): a combination of familiar elements according to known methods is obvious when it does no more than yield predictable results; the "finite number of identified, predictable solutions" test; design incentives and market forces count as motivations; "[t]he combination of familiar elements according to known methods is likely to be obvious…"
• MPEP 2143/2144 articulated rationales I rely on: (A) combining prior art elements according to known methods; (C) obvious to try from a finite set; (D) known technique to improve similar devices; (F) design incentives/market forces; (G) teaching away absent.

Level of ordinary skill (proposed): a software engineer with ~2 years' experience in network application/server programming (WWW/HTTP, e‑mail, and telephony/data gateways) and interactive 3‑D/VRML graphics, plus familiarity with consumer simulation games. This is the level reflected by the '328 specification itself (VRML 2.0, Java, Community Place Browser/Bureau, CGI/e‑mail).

2. The prior-art references and their §102 status

Explicitly excluded as §103 art: WO 98/25235 (Shetty) — its publication date (1998‑06‑11) postdates the '328 filing (1998‑05‑26); I therefore do not rely on Shetty despite its close subject-matter fit, and instead use Pershan 5,260,986 and EP 0 798 899 A1, whose dates clearly qualify. Also flagged: JP 6577328 B2 (Furukawa Battery) is an unrelated identifier-match and is not this patent.

3. Claim chart — independent claims 1 / 10 / 11

I treat the three independent claims as one set (they recite the same invention in medium / apparatus / method form, per the summary's plain-language holdings).

On this record, every element of claims 1/10/11 is disclosed, and all three references are combinable, giving a strong prima facie §103 case.

4. The four combinations, with articulated motivations

Combination A (core claims 1, 10, 11): R1 (Habitat/VRML‑2.0 shared world) + R2 (Tamagotchi / US 5,572,646 / US 6,227,966) + R3 (Pershan 5,260,986 / EP 0 798 899).

Motivation, in the order the PTAB/CAFC expects:

1. The '328's own admitted problem supplies the motivation. The specification states that the prior standalone pets "suppose application to a standalone apparatus… the existing space or breeding environment of the virtual creature is concluded in that apparatus," and that "the owner or other users cannot remotely acquire the information associated with the growth process… and remotely breed the same." Under MPEP 2129 / In re Nomiya, this is the applicant's own identification of the problem — evidence that the solution was desired, not inventive.
2. R2's design creates the incentive. R2b (Tamagotchi) makes the pet request food/sleep/attention on a calendar timer and die or regress if ignored — the exact market/design pressure that logically drives a remote notification channel (KSR "design incentives; market forces").
3. R3 supplies a known technique applied to a known device. Pershan (1993) teaches the precise "control table + registered notification method + registered address → send message on event" architecture for any monitored condition; substituting a virtual creature's status transition for Pershan's notification trigger is a known technique to improve a similar device, yielding predictable results (MPEP 2143(A), (D); KSR).
4. Reasonable expectation of success / structural congruence. The '328 itself implements R3 with an ordinary e‑mail server 15 and a communication server 16 — i.e., standard network infrastructure already present in R1d (WWW/Community Place) systems. No new hardware or unpredictable engineering was required.
5. Finite, identified, predictable solutions. Once the problem is posed, the field offered only a few choices for notifying an absent user: e‑mail, pager, fax, telephone/text-to-voice (all named in the '328). Choice among these is a selection of a known number/extent of a single known parameter (MPEP 2144.04), not inventiveness.

Combination B (dependent claims 2–4 — access-history-triggered messages; selection among plural message statements): R3a + R3c + R2.
Pershan's notification-list management and Lawson's event-registry logic teach triggering on monitored conditions and configuring what/who is notified. Selecting among pre-written message statements based on the elapsed time since last access (the "I miss you" / "Thank you for playing" examples) is the routine application of conditional message templates — a predictable programming choice. Motivation: heighten the retention effect already stated in the '328's own text ("evoke a motivation of a kind that the user must soon access the virtual pet… the service provider can ensure regular access").

Combination C (dependent claims 5 & 7 — e‑mail (5); facsimile with automatic outgoing call (7)): R3a/R3b + R1d.
Pershan expressly teaches notification by pager/telephone; EP 0 798 899 teaches delivering server-held messages to a subscriber terminal (and by fax-capable/telephone activation). Adding e‑mail or automatic‑dial fax is use of familiar channels with predictable results. E‑mail was the default messaging service of R1a/R1d systems.

Combination D (dependent claim 8 — reverse path: interpret an operation command returned with a caller ID through a simple communication apparatus, e.g. DTMF, and reflect it onto the virtual life object's status transition): R3a + R2 + conventional DTMF remote-control art.
Pershan expressly discloses changing a notification list "from any DTMF telephone" and pre‑established user numbers — i.e., inbound DTMF commands mapped to a user account. Caller ID was standard telephony (the '328 admits using "caller ID"). Feeding a DTMF/caller-ID command into the pet's growth-parameter update is the same known technique applied to the R1/R2 object — MPEP 2143(A)/(D). Motivation: "the keeper can later check requests of the virtual pet and make communication with it" (spec's stated aim).

Combination E (for the FPO/Justia-amended claim 1, if the reexamination-certificate theory is correct): the added limitations — a growth parameter control table classified into virtual life data and keeper data, "continuous autonomous transformation based on modifiable growth parameters comprising physical and mental parameters," updated by a predetermined growth-parameter equation on a timer event after a keeper-initialized birth date — are taught by R2a (US 5,572,646: register-based growth degree computed on timers) for the growth side and R3a (per-user profile/record) for the keeper-data side. Their union in a single table is the ordinary unification of two known database schemas — no synergy, no unexpected result (MPEP 2143(A); KSR "mere aggregation").

5. Anticipated patent-owner rebuttals and why they likely fail

6. Conclusion

On the reconstructed record, claims 1, 10 and 11 of U.S. 6,577,328 would have been prima facie obvious under §103 as the predictable combination of (R1) a networked/VRML shared virtual world (Habitat, VRML 2.0 Behavior, Community Place; admitted prior art and §102(b)), (R2) a timer-driven virtual-creature breeding simulation with growth parameters (US 5,572,646 §102(b); Tamagotchi; admitted prior art), and (R3) a profile-driven event-notification system that registers a notification method and a contact address and sends a message upon a monitored condition (US 5,260,986 §102(b); EP 0 798 899 A1 §102(b)). The applicant's own admitted statement of the problem and the Tamagotchi design's demand for attentiveness supply an express motivation. Most dependents (access-history messages, message selection, e‑mail, fax-with-autodial, caller‑ID/DTMF reverse control) fall to the same references plus routine engineering.

Confidence: moderate‑to‑high for the core claim set; lower for the amended claim 1 / claims 12–20, because (i) I was not given the official claim text or any reexamination certificate (a discrepancy carried over from your earlier sections), and (ii) I was not given the actual "Prior Art" section you referenced. To convert this into a defensible invalidity position, pull (a) the as‑granted and any post‑grant-reissue/reexam claim text from USPTO PatentCenter, (b) the examiner's cited‑art list on the '328 file wrapper, and (c) the Shetty WO 98/25235 §102(e) date analysis (which I deliberately excluded here) before finalizing. Also note the prior sections' unresolved points: the FPO/Justia claim-set discrepancy (possible C1 certificate) and the ambiguous current ownership (LINE CORPORATION 2015 reassignment vs. Google's "Z Intermediate Global Corp." listing).