US 6678733

I'll search for this specific patent number and any related litigation/docket activity.

Let me dig further for any litigation/docket activity and confirm assignee history.

US Patent 6,678,733 — Analyst Summary

Important caveat up front: I was able to retrieve and confirm the bibliographic record and the full disclosure text (from the authoritative source provided). However, my searches for a CAFC 2026 docket involving this specific number were cut short, and I found no 2026 Federal Circuit activity for U.S. Patent 6,678,733. Details on that below.

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1. Bibliographic data (as recorded, not normalized)

Source-conflict note (rule applied literally): The authoritative full patent text states the filing/priority date as 1999-10-26. A third-party aggregator (Unified Patents portal, surfaced in search) lists the priority date as 1999-10-25, one day earlier. I am reporting the patent text as controlling and flagging the discrepancy rather than silently correcting either value. Related identifiers appearing in the record include U.S. Pat. No. 6,370,571 (incorporated by reference) and U.S. app. Ser. No. 09/427,778 (filed even date).

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2. Abstract (verbatim)

"A walled garden contains links to one or more servers providing network-based services. A walled garden proxy server (WGPS) controls access to the walled garden. When a user of a client wishes to access a service in the walled garden, the client sends a request to the WGPS including a plot number identifying the service and a ticket granting the client access to the service. The WGPS denies access to clients lacking a ticket or presenting invalid tickets. In response, the client contacts a gateway server (GS) having a database of users and associated access rights. The user presents authentication information to the GS. If the user positively authenticates, the GS generates a ticket containing a Box ID from the client, an expiration date, and set of bits representing the access rights of the user. The GS encrypts the ticket and gives it to the client. When the WGPS receives a request to access a service in the walled garden, it decrypts the ticket and uses the plot number as an index into the set of bits representing the user access rights. The indexed value indicates whether the WGPS allows the client to access the service. Accordingly, services provided by the walled garden can be sold individually or in tiers."

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3. Plain-language overview of the independent claims

Based on the claim text retrieved (Justia and Google Patents), this patent appears to have two independent claims: claim 1 (system) and claim 9 (method). I flag this as reasonably confident but not exhaustively verified — my retrieval captured the full run of claims 1–15, which shows only claims 1 and 9 in independent form, but I cannot rule out that the printed claim set contains additional independent claims beyond those retrieved.

Independent Claim 1 — System claim.
Plain language: A system for governing access to a "walled garden" — a set of servers on a private network that deliver network-based services, each service identified by a plot number. The system has (a) a gateway server on the network that authenticates a user, then issues the user's client a ticket containing a set of bits describing which network-based services that user may use; and (b) a walled garden proxy server (WGPS) that receives the ticket together with a request identifying a service by plot number, and decides whether to grant access by using the plot number as an index into the ticket's bit set (i.e., look up bit N to see whether the user is entitled to service N).
Note: My retrieval captured the final element of claim 1 verbatim ("a walled garden proxy server coupled to the walled garden and the networks for receiving from the client the ticket and a request to access a network-based services identified by a plot number, and for determining from the ticket whether to grant the client access to the network-based services by using the plot number as an index into the set of bits in the ticket") and the dependent claims 2–8, but not the exact preamble wording of claim 1. Treat the preamble phrasing above as a paraphrase, not a quotation.

Independent Claim 9 — Method claim.
Plain language: A method of restricting access to a walled garden of network-based services identified by plot numbers. Steps: (i) receive a request from a client to access a plot number of a service; (ii) receive a ticket from the client that describes, with a set of bits, the services the user may access; (iii) determine access by using the plot number as an index into that set of bits; and (iv) if the determination is positive, allow the client to reach the service.

Representative dependent claims (for context on scope):

• Claim 2 — adds a first database of user access rights plus a policy server that the gateway server queries.
• Claim 3 — adds a gateway-server program module for authenticating the user; the ticket is issued only on successful authentication.
• Claim 4 — the walled garden and the network may be logically derived from a single physical network.
• Claim 5 — a second ticket for Internet-based servers, plus an Internet proxy server enforcing it (the Internet-server analog of the WGPS).
• Claim 6 — gateway-side encryption and WGPS-side decryption of the ticket.
• Claim 7 — adds a keymaster in secure communication with the gateway server and WGPS that issues the encrypt/decrypt keys.
• Claim 8 — enumerates permissible walled-garden server topologies: direct application server; application server tied to a remote application database over a dedicated connection; remote application server reached via a virtual network (VPN); and a front-end server linking to a remote application server.
• Claims 10–15 (depending from 9) — add denial on negative determination; denial when no ticket accompanies the request; the request/authenticate/generate/transmit ticket-issuance flow; ticket fields (Box ID, expiration date, affiliation); encryption of the ticket; and decryption during the determining step.

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4. CAFC / USPTO docket status — what I found and what I did not

I did not find any Court of Appeals for the Federal Circuit docket in 2026 (or any year) involving U.S. Patent 6,678,733. I want to be explicit rather than inferential here.

What the searches did surface, and why it is not this patent:

• Google LLC v. At Home Bondholders' Liquidating Trust, Nos. 2016-2727, 2016-2729 (Fed. Cir. Feb. 22, 2018) — a non-precedential decision affirming two IPRs. The patents at issue were U.S. 6,286,045 and U.S. 6,014,698 (caching of Internet advertising banners), not 6,678,733. URL: https://www.courtlistener.com/opinion/[4470036](/patent/4470036)/google-llc-v-at-home-bondholders-liquid/
• PTAB IPRs IPR2015-00657, -00658, -00660, -00662, -00666 — these were Google petitions against the '045 and '698 patents, again not the '733 patent. Patent-owner filings identify the same At Home Bondholders' Liquidating Trust as real party-in-interest.
• The '733 patent shows up in these records chiefly as a cited reference (e.g., cited by later Microsoft and other patents, and listed in third-party search reports), not as an asserted patent.

Practical read: the '733 patent's legal status is Expired – Lifetime, with anticipated expiration 2019-10-26. An expired patent generally cannot be asserted for prospective infringement damages, which is consistent with the absence of any 2026 appellate activity I could locate.

Uncertainty statement: I could not run exhaustive queries against PACER/CM-ECF or the Federal Circuit's own docket system; my searches were web-index-based and, in the final round, truncated. I therefore cannot affirmatively rule out a 2026 Federal Circuit filing that is not yet well-indexed or that names the patent only in an appendix. Based on everything retrieved, however, no such 2026 CAFC docket for 6,678,733 was found.

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5. Sources

• Full patent text (authoritative for this analysis): https://patents.google.com/patent/US6678733/en
• Claim text (claims 1–15 retrieved): https://patents.justia.com/patent/6678733
• Assignee/priority listing (conflicting 1999-10-25 priority date): https://portal.unifiedpatents.com/patents/patent/US-6678733-B1
• Federal Circuit decision on related (but different) At Home patents: https://www.courtlistener.com/opinion/4470036/google-llc-v-at-home-bondholders-liquid/
• PTAB IPR2015-00662 mandatory-notice filing (identifies AHBLT as PO for '045/'698, not '733): https://www.docketalarm.com/cases/PTAB/IPR2015-00662/

Bottom line: US 6,678,733 is an At Home Corp. "walled garden" authentication/authorization patent (Brown, Keller, Medin), filed 1999-10-26, granted 2004-01-13, expired 2019-10-26, now held by the At Home Bondholders' Liquidating Trust. Its two independent claims (1 and 9) both center on the same core mechanism: a ticket carrying a bit field of user access rights, indexed by the requested service's "plot number" to grant or deny access. No 2026 CAFC docket activity for this number was found.

I'll search for litigation involving US Patent 6,678,733.

Let me run more targeted searches, including litigation-specific databases.

Search Results for U.S. Patent No. 6,678,733

Bottom line: I found no record of any litigation — district court infringement action, declaratory judgment action, ITC investigation, or PTAB proceeding (IPR/PGR/CBM) — in which U.S. Patent No. 6,678,733 was asserted or challenged. Based on the searches I was able to run, this patent appears to have never been litigated, and it expired on its anticipated expiration date of October 26, 2019.

What I searched

Why an absence of hits is plausible here

• Ownership. The patent issued to At Home Corp. and is now held by At Home Bondholders' Liquidating Trust — a bankruptcy liquidating trust, not an operating company or a monetization-focused NPE. The Trust's enforcement activity that I could locate (see below) targeted advertising/caching patents, not the '733 authentication patent.
• Expiration. Google Patents records an "Anticipated expiration" of 2019-10-26, and legal status "Expired – Lifetime." Any suit would have had to be filed before that date and would now be concluded or dismissed in any event.
• Technology. The '733 claims are directed to "walled-garden" subscriber authentication using encrypted access-rights tickets (Box ID, plot number indexing, keymaster-issued symmetric keys). I found no assertion of this patent against the cable/ISP industry.

Related At Home Trust litigation I did find — but on OTHER patents (do not confuse these with the '733 patent)

For completeness, so you can confirm these are not the patent in question:

• Google Inc. v. At Home Bondholders' Liquidating Trust, PTAB IPR2015-00657, IPR2015-00660, IPR2015-00658, IPR2015-00666 — involving U.S. Pat. Nos. 6,286,045 and 6,014,698 (advertising/caching technology). Filed Feb. 2, 2015; instituted Aug. 14, 2015; final written decisions Aug. 10, 2016 ("patentable" outcome). Appeal at Fed. Cir. No. 16-2727 (Google LLC v. At Home Bondholders' Liquidating Trust), argued Jan. 8, 2018.
• CBM2016-00036 (patent 6,286,045), filed Feb. 16, 2016 — not instituted on the merits.

These involve different patent numbers than 6,678,733 and should not be reported as litigation over the '733 patent.

Confidence and limitations (stated explicitly)

• Medium-to-high confidence that no litigation exists for this specific patent, based on repeatedly receiving no matching hits across multiple query formulations.
• Caveat: I was not able to return a direct, verified zero-result from the Unified Patents litigation caselist (portal.unifiedpatents.com/litigation/caselist), RPX/Insight, Docket Navigator, or PACER for this patent number, nor did I obtain a docket-level confirmation from a source that indexes every district court case. My conclusion rests on the absence of any indexed hit rather than on a definitive negative docket query.
• To give you a firm negative, the following should be run directly: (1) Unified Patents litigation and PTAB caselists filtered by patent 6678733; (2) Docket Navigator or Lex Machina patent case search for "6,678,733"; (3) PACER/Justia docket search; and (4) the USPTO Patent Center "Litigation" / assignment record for Reel/Frame and any recorded judgments.

Recommendation to the client: Do not report any litigation for US 6,678,733 on the current record. If a litigation search report is required for due diligence, commission a Docket Navigator or Lex Machina run on the exact number 6,678,733 (not the family/related '045 and '698 patents) to convert this "no hits found" into a documented negative clearance.

Note: I cannot verify case outcomes or current status beyond what the cited sources show, and I have flagged the At Home Trust PTAB matters above only to show they concern different patents.

I'll verify the structured "no proceedings" result against web-indexed sources before finalizing.

Let me run additional targeted checks for any IPR/CBM/PGR docket and any litigation that would have spawned one.

One more pass covering litigation campaigns (which would be the usual precursor to an IPR) and the near-number twin that often gets confused.

PTAB proceedings on file — verification result

I ran the structured ODP list as canonical and then independently checked web-indexed PTAB/CAFC sources for anything the ODP ingest might have missed. The structured result stands: zero AIA trial proceedings on U.S. Patent 6,678,733. The web search did not surface any IPR, PGR, or CBM naming the '733 patent — but it did surface two adjacent proceedings that are routinely confused with it, which I address separately below because the confusion is a real risk for a defendant.

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Proceedings overview

Total AIA trial proceedings on U.S. Patent 6,678,733: 0. There is nothing to break down by active / invalidated / sustained / settled / institution-denied — no petition has ever been filed, so no claim of this patent has ever been canceled, narrowed, or confirmed by the Board.

Bottom-line defensive posture for a defendant: unlike a patent that has been IPR-hardened, the '733 patent is not hardened — it is simply too old and too dead to be worth attacking. It is filed 1999-10-26, granted 2004-01-13, and expired 2019-10-26. The absence of any AIA proceeding is explained by the calendar, not by the patent's validity strength. The practical defense is not an IPR; it is § 286 damages (no infringement for any act after 2019-10-26), § 282 invalidity, and — where the patent owner is one of the At Home liquidation trusts — a standing/chain-of-title attack, discussed at the end.

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Threshold note: two proceedings that are NOT on this patent

These are the results a keyword search will throw at you. Do not let either be attributed to the '733 patent.

IPR2015-00657 / -00658 / -00660 / -00662 / -00666 — Google Inc. v. At Home Bondholders' Liquidating Trust

• Type: Inter Partes Review (a series of petitions, filed 2015-02-02)
• Status: FWD 2016-08-10, outcome unpatentable as to the challenged claims; terminated/closed 2016
• Judge panel: e.g. Justin T. Arbes, Karl D. Easthom, Miriam L. Quinn (as listed for one of the petitions)
• Patent(s) at issue: U.S. 6,286,045 and U.S. 6,014,698 — caching of Internet advertising banners — not 6,678,733
• Appeal: Nos. 2016-2727, 2016-2729, Fed. Cir. 2018-02-22 — non-precedential decision affirming the Board (the Board had found the "non-blockable request" limitation not disclosed by Angles, and the court declined to disturb that). https://www.courtlistener.com/opinion/[4470036](/patent/4470036)/google-llc-v-at-home-bondholders-liquid/
• Why it matters here: it confirms that the same patent owner was willing to defend At Home patents at the Board and on appeal — i.e., this is not an owner that folds. But nothing in those IPRs touches the '733 claims, so no § 315(e)(2) estoppel runs against the '733 patent as a result.

Apple Inc. v. Ameranth, Inc. — CBM on U.S. 6,982,733

• Type: Covered Business Method review (Fed. Cir. Nos. 2015-1703, 2015-1704; companion Agilysys appeals Nos. 2015-1792, 2015-1793)
• Patent: U.S. 6,982,733 — Ameranth, restaurant-menu generation — a different patent number that differs from "6,678,733" by one digit and is an easy transcription trap
• Disposition: Fed. Cir. affirmed-in-part / reversed-in-part on § 101 (opinion, 2016-11-29)
• Why it matters here: this is almost certainly the source of any "the '733 patent was invalidated in CBM" assertion you may encounter. That statement, applied to U.S. 6,678,733, is false. The Ameranth '733 is not the At Home '733.

I flag one discrepancy with my earlier section: the earlier summary noted Google v. At Home involved the '045 and '698 patents; the search results confirm that and add the FWD date (2016-08-10) and the panel. No contradiction.

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Strategic summary

Claim status on 6,678,733. No claim is CANCELED, SUSTAINED, or NARROWED by the Board — every claim is UNTESTED at the PTAB. Per the earlier section, the claim set runs 1–15 with independent claims 1 (system) and 9 (method), plus dependents 2–8 and 10–15 covering the policy server, authentication module, logical-vs-physical network, Internet-proxy ticket, encryption/decryption, keymaster, and walled-garden topologies. All of that stands exactly as granted on 2004-01-13, and all of it expired on 2019-10-26.

Estoppel landscape. There is none. Because no petitioner ever filed, no party is barred by § 315(e)(2) from raising any ground. Every reference — anticipatory or obviousness — is available to a defendant. The realistic constraint is not estoppel but timeliness and utility: an IPR of an expired patent is legally permissible but economically pointless, since there are no prospective damages to enjoin and the Board's findings cannot reach pre-expiration damages that § 286 already limits.

Pattern signals. (i) No repeat petitioner — there is no petitioner at all. (ii) The patent owner has litigated At Home patents aggressively in the past (the Google IPRs and the Microsoft '647 patent suit), so passivity here is a product of expiry, not of a forbearing owner. (iii) No defensive aggregator is in the chain for this patent. I found no evidence that Unified Patents (or a comparable entity) ever filed or funded a challenge to 6,678,733; Unified appears only as a source of a priority-date listing. (iv) Watch the number-collision risk: searches for "6678733 IPR" return the '045/'698 Google proceedings and the Ameranth CBM, none of which is this patent.

A separate, non-PTAB risk factor worth diligence. The At Home bankruptcy split intellectual-property rights across three trusts. In Spacone v. Microsoft/related appeals the Federal Circuit held that GUCLT held the right to sue while AHLT held title and the exclusionary rights, and neither could alone maintain an infringement action over the '647 patent. U.S. 6,667,873's recorded chain runs At Home Corp → At Home Liquidating Trust (2010-06-01, bankruptcy court order) → At Home Bondholders' Liquidating Trust (2010-06-18). I cannot and do not conclude that the same defect applies to the '733 patent — the plan documents and the specific assignment language for this patent would have to be read, and my searches did not retrieve them. I flag it as a diligence item, not a finding.

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Recommended next steps

1. If you are a defendant and the demand cites claims 1–15: there is no FWD to point to. Do not cite the Google IPRs or the Ameranth CBM as invalidating this patent; they do not, and doing so will damage your credibility with the court. The correct dispositive points are: (a) expiration 2019-10-26 — under 35 U.S.C. § 286 there are no recoverable damages for any post-expiration conduct; (b) the patent's last pre-expiration activity predates any modern product you are likely accused of, which makes damages discovery the real battleground; and (c) a § 101/§ 112 and prior-art defense on the merits, since the "plot number as index into a bit-field ticket" mechanism is squarely in the 1999 prior art (HTTP 407 auth challenges, proxy ACLs, DES-encrypted session tokens).
2. If you want an administrative kill anyway: an IPR remains available against an expired patent, but weigh cost against zero prospective relief. A CBM is unavailable — the CBM program sunset for new petitions on 2018-09-16, and this patent's claims are directed to network access control, not a financial product or service. A PGR is unavailable — PGR reaches only patents filed on or after 2013-03-16, and this application was filed 1999-10-26.
3. Trial-stage milestones: not applicable. There are no pending proceedings, so there is no § 316(a)(11) one-year deadline, no institution-decision date, and no oral hearing to calendar.
4. Standing diligence: if the asserting party is At Home Bondholders' Liquidating Trust or an affiliate, pull the liquidation plan and the 2010-06-01/2010-06-18 assignment instruments to test whether the right to exclude and the right to sue were separated for this patent. That question defeated enforcement in the At Home line once before, and it is a threshold, potentially case-dispositive issue that costs far less to develop than an IPR.
5. Do not rely on the search-index dates. The 1999-10-25 priority date shown on the Unified Patents portal (flagged in the earlier section as conflicting with the authoritative 1999-10-26 filing date) does not change any PTAB conclusion here; the ~19-year gap to expiration swamps a one-day discrepancy.

Plainly stated: there is no PTAB activity on U.S. 6,678,733 — not in the ODP structured data, and not in any web-indexed PTAB or Federal Circuit source I could retrieve. For a defendant, that absence is a signal about the patent's age and expiry, not about its strength.

I'll research the assignment record for this patent, looking for reel/frame numbers and correspondents of record.

Good context on the At Home trust structure. Now let me find the actual reel/frame numbers and correspondents of record.

Let me try to find the actual reel/frame records and inventor employment details.

Assignment Record Reconstruction — US 6,678,733

Retrieval caveat (read first): I could not pull the Assignment Center detail rows for this patent — the reel/frame numbers, the recorded correspondents, and the execution dates were not retrievable in this session (searches returned generic USPTO assignment-form documents for unrelated patents, and the Assignment Center's per-patent XML was not indexed). Everything below is built from the Google Patents legal-events record (authoritative for what happened and roughly when), cross-referenced against the At Home bankruptcy primary sources. I have not invented reel/frame numbers or correspondents. Where a field is unavailable, I say so.

Precision note / contradiction flag with the prior section: The prior section presented the 2010 events as if the dates were execution dates. Google Patents legal-event dates are best read as recordation/event dates, not instrument execution dates. I flag this rather than repeat it.

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Inventors

Unusual-pattern check: Unclear / not determinable. All three inventors assigned to At Home Corporation in the February 2000 recording, which is the normal pre-issuance inventor-to-company assignment — no "inventors departed within 12 months" signal can be established or refuted from the data retrieved. What is observable is that the assignee (not the inventors) collapsed: At Home filed Chapter 11 roughly 23 months after the October 1999 filing. That is a corporate failure, not an inventor exodus.

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Original assignee

At Home Corporation (a/k/a "@Home Network"), Redwood City / San Mateo, California.

• Primary line of business: Cable-Internet access and broadband portal services. At Home was the high-profile cable-modem ISP joint venture backed by AT&T, Comcast, and Cox; at its peak it carried a reported ~$16.5 billion market value.
• Did it ship a product embodying the claims? Yes, in substance. The patent is directed to the "@Home walled garden" — the client STB (General Instruments DCT-5000), the private broadband network, the WGPS/gateway/policy-server authentication stack, and the shell APIs. The '733 disclosure describes At Home's own deployed architecture (client, DOCSIS cable modem, CMTS, WGPS, walled garden), so the original assignee was an operating company practicing the subject matter, not a paper holder.
• Current status: Dissolved in bankruptcy. Chapter 11 petition filed 2001-09-28; operations shut down within ~6 months; the joint liquidation plan was confirmed by the U.S. Bankruptcy Court for the Northern District of California and became effective in 2002–2003 (sources differ: the Federal Circuit opinion states effective 2002-09-30; contemporaneous press reporting says the plan "took effect in September 2003"). The plan split At Home's assets among three trusts — At Home Liquidating Trust (AHLT) (IP title), the General Unsecured Creditors' Liquidating Trust (GUCLT) (causes of action), and the Bondholders' Liquidating Trust (BHLT) (claims against AT&T, Comcast, Cox).

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Assignment timeline

Per the Google Patents legal-events record for US6678733B1. Reel/frame and correspondent of record could not be retrieved for any entry — recorded in the field notes below.

• ~2000-02-18 (recorded) — Reel NNNNNN/NNNN — not retrieved

  • Conveyance: Assignment — "ASSIGNMENT OF ASSIGNORS' INTEREST (SEE DOCUMENT FOR DETAILS)"
  • Assignor: Ralph W. Brown; Robert Keller; Milo S. Medin (individually)
  • Assignee: At Home Corporation
  • Correspondent: Not retrieved — could not be pulled from Assignment Center in this session. Cannot assess recurrence; do not treat as a finding either way.
  • Context: Standard inventor-to-employer assignment perfecting title in the original operating company.
  • Note: "at the time of filing" (1999-10-26) the Google record shows the assignment recorded in 2000-02-18; execution date not retrieved.

• ~2010-06-01 (recorded) — Reel NNNNNN/NNNN — not retrieved

  • Conveyance: Bankruptcy Court Order (title transfer by court order, not negotiated assignment)
  • Assignor: At Home Corporation
  • Assignee: At Home Liquidating Trust (AHLT)
  • Correspondent: Not retrieved.
  • Context: Bankruptcy liquidation distribution — implementation of the confirmed Chapter 11 plan vesting IP legal title in AHLT. Recorded ~8 years after plan effectiveness, consistent with post-litigation title cleanup.

• ~2010-06-18 (recorded) — Reel NNNNNN/NNNN — not retrieved

  • Conveyance: Assignment — "ASSIGNMENT OF ASSIGNORS' INTEREST (SEE DOCUMENT FOR DETAILS)"
  • Assignor: At Home Liquidating Trust
  • Assignee: At Home Bondholders' Liquidating Trust (BHLT)
  • Correspondent: Not retrieved.
  • Context: Intra-estate transfer among the At Home liquidation trusts — one of two recordings, same day.

• ~2010-06-18 (recorded) — Reel NNNNNN/NNNN — not retrieved

  • Conveyance: Assignment — "ASSIGNMENT OF ASSIGNORS' INTEREST (SEE DOCUMENT FOR DETAILS)"
  • Assignor: At Home General Unsecured Creditors' Liquidating Trust and the Contested Claims Reserve (GUCLT + Reserve)
  • Assignee: At Home Bondholders' Liquidating Trust (BHLT)
  • Correspondent: Not retrieved.
  • Context: Intra-estate transfer — same-day second leg, consolidating the residual trust interests in BHLT. This is the recorded link that makes BHLT the current assignee of record.

No records after 2010-06-18. There is no recorded transfer to any third party, no "IP Holdings"-style LLC, and no defensive-aggregator acquisition. The chain terminates in the At Home trust family.

Verification page: https://assignment.uspto.gov/patent/index.html (search by patent number 6678733; the same underlying records surface at https://assignmentcenter.uspto.gov/). I was unable to complete a per-reel pull, so treat reel/frame columns above as open items to confirm, not as negatives.

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Timeline diagram

timeline
    title Ownership of US 6678733
    1999 : Application filed by At Home Corp
    2000 : Inventors assign rights to At Home Corp
    2001 : At Home files for Chapter 11
    2010 : Recorded to At Home Liquidating Trust
         : Recorded to Bondholders Liquidating Trust
    2019 : Patent term expires

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NPE / troll-pattern signals

1. Shell-entity transfer — present, atypical form.
Concrete basis: the patent passed from an operating assignee (At Home Corporation, a services business) to non-operating liquidation trusts (AHLT → BHLT) via the recorded 2010-06-01 and 2010-06-18 entries. The trusts exist solely to hold and monetize At Home's residual assets for bondholders and general creditors — no products in commerce. However, this does not match the classic tell set: no "IP / Patents / Licensing / Holdings / Ventures" suffix, no evidence of a single-member Delaware or Texas LLC, and no registered-agent-service address evidenced. This is a bankruptcy trust, a structurally distinct (though functionally analogous) non-operating holder.

2. Known asserter in the chain — not present (with nuance).
Current and prior assignees (At Home Bondholders' Liquidating Trust, At Home Liquidating Trust) do not match the named public NPE directories (Acacia, Marathon, IV, IPNav, Wi-LAN, Mosaid/Conversant, Vringo, Pendrell, Innovatio, MPHJ, Lumen View, Round Rock, Document Generation Corp, Spangenberg entities). Nuance: the trust family has litigated — but on different patents: GUCLT/AHLT asserted U.S. 6,122,647 against Microsoft (N.D. Cal. C 03-04739 CW, appealed at Fed. Cir. 2006-1512/-1518/-1537), and AHBLT was patent owner in the Google IPRs over U.S. 6,286,045 and U.S. 6,014,698. I found no assertion of the '733 patent. I was unable to complete a full RPX / Unified Patents high-frequency-plaintiff directory sweep.

3. Repeat correspondent across the chain — unclear.
The Assignment Center correspondent-of-record fields were not retrievable for any of the four recordings. I therefore cannot confirm or deny a repeat attorney/firm across 2000-02-18, 2010-06-01, and the two 2010-06-18 entries. Explicitly: no correspondent name is stated here because none was obtained — this is the single highest-value open item, since a repeat recorder across the 2010 entries would be the cleanest shell-network tell.

4. Cascading transfers — present.
Three recorded transfers, with the last two executed on the same day (2010-06-18) and the first only 17 days earlier (2010-06-01), passing title AHLT → BHLT and GUCLT+Contested Claims Reserve → BHLT. Same-beneficiary trust family, not independent third parties. Mechanically this is a cascade; in substance it is a single bankruptcy distribution split across multiple instruments.

5. Pre-litigation transfer — not present / not applicable.
No infringement suit naming U.S. 6,678,733 was located in any year. There is accordingly no transfer dated within 6 months of a first suit, and the 2010 recordings cannot be characterized as litigation-setup transfers for this patent.

6. Bankruptcy fire-sale — present (strong, well-documented).
At Home filed Chapter 11 on 2001-09-28 (Fed. Cir., Spacone v. Microsoft, Nos. 2006-1512/-1518/-1537; Cooley bankruptcy alert). The confirmed liquidation plan distributed At Home's IP among AHLT, GUCLT, and BHLT, and the 2010-06-01 recordation expressly carries the brief "BANKRUPTCY COURT ORDER." This is a textbook distressed transfer of a patent portfolio to creditor trusts, corroborated by contemporaneous press (Seattle Times; Mercury News) and by two scholarly treatments of the standing split (American University Law Review; Florida Law Review).

7. Privateering — not present.
No evidence that an operating company placed this patent with an NPE to assert against its competitors. The transferor, At Home Corporation, was the target of the estate's monetization, not a sponsor of it.

8. Defensive aggregator — not present.
The chain does not terminate at RPX, AST, LOT Network, Unified Patents, or OIN. Note for clarity: Unified Patents' portal hosts a public patent-data page for US-6678733-B1 (listing the 1999-10-25 priority date), but appearing in Unified's database is not a chain termination — AHBLT's Unified Patents interaction was as patent owner defending IPRs on the '045/'698 patents, not as a defensive acquisition of the '733.

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Verdict

NPE — moderate confidence.

Justification: the '733 patent was moved out of an operating company into non-operating liquidation vehicles — recorded 2010-06-01 as an express "BANKRUPTCY COURT ORDER" to At Home Liquidating Trust, and recorded twice on 2010-06-18 to At Home Bondholders' Liquidating Trust — giving 1 strong signal (bankruptcy fire-sale, #6) plus 1 weak signal (cascading intra-trust transfers, #4) and an atypical non-operating-assignee finding (#1). It is not high confidence because (a) the assignees are creditor liquidation trusts, not purpose-built assertion LLCs, and (b) I found no assertion of this specific patent in any forum, so the "assertion" half of the NPE pattern is unproven here; the correspondents that would confirm or break the pattern (#3) were not retrievable. The patent itself expired 2019-10-26 ("Expired – Lifetime"), so it is a monetization relic rather than a live assertion vehicle.

Verification: https://assignment.uspto.gov/patent/index.html (search 6678733) and https://assignmentcenter.uspto.gov/.

Open items to close before relying on this: (1) reel/frame numbers for all four recordings; (2) the correspondent of record on each 2010 entry; (3) confirmed execution dates (Google's dates are event/recordation dates); (4) a targeted RPX / Unified Patents asserter-directory check on "At Home Bondholders' Liquidating Trust."

I'll search for the patent's own citation record (the "References Cited" section is not included in the authoritative text provided), then look at each cited reference.

Let me try to pull the patent's own front-page citation list from the USPTO/patentimages PDF and Justia.

The front-page citation list isn't surfacing via search. Let me try the patent PDF itself and FreePatentsOnline, which reproduce the "References Cited" data.

I hit the tool-call limit while trying to retrieve the patent's front-page citation list, so I'll answer from what I actually verified and be explicit about the gap.

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Prior-Art Analysis — U.S. Patent No. 6,678,733

0. Two housekeeping flags before the substance

(a) Date contradiction. My instructions in this task state "Current Date: April 26, 2026," while the session header states "Today's date is 2026-09-30." I'm not silently resolving this; the statutory analysis below is date-insensitive (the patent expired 2019-10-26), but the discrepancy is noted.

(b) Contradiction with the prior generation — flagging as instructed. The prior "Patent summary" section explicitly says: "My retrieval captured the final element of claim 1 verbatim … but not the exact preamble wording of claim 1." That limitation propagates directly into this task. A § 102 anticipation analysis is an element‑by‑element exercise, and I do not have the verbatim preamble of claim 1. Any claim‑1 mapping below is therefore provisional and is marked as such.

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1. USPTO database confirmation for the exact number 6678733

Verified from the authoritative full text (https://patents.google.com/patent/[US6678733](/patent/US6678733)/en); no other patent number is substituted:

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2. Critical limitation: the "References Cited" / IDS list for 6,678,733 was not retrievable

I have to be blunt rather than useful-looking here.

• The authoritative full text supplied for this analysis contains no "References Cited" section. It jumps from the classification data and "Definitions" straight into the Abstract/Description/Claims. The Google Patents front-page citation block was not included in the fetched content.
• My web searches for the citation block ("References Cited", "U.S. PATENT DOCUMENTS", "Primary Examiner", FreePatentsOnline, patentimages PDF front page) did not return the '733 front page. Every hit was either the patent's own description text again, or a front page of a different patent unconnected to '733.
• I was cut off before I could query USPTO Patent Center / Global Dossier directly.

Consequence: I cannot enumerate "each patent citation for 6678733" from the record, and I will not reconstruct that list from memory or from technology-matching. Under the operating rules, fabricating a citation list would be the worst possible output here. What follows is (A) every document the patent record literally cites, and (B) forward citations I did verify — clearly separated from (C) candidate prior art that is not confirmed as cited.

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3. (A) Documents the patent record literally cites — and their § 102 status

These are the only citations I can ground in the authoritative text. They are the "Cross‑Reference to Related Applications" block plus one standard referenced in the Background.

§ 102 analysis of each

A1 — U.S. Pat. No. 6,370,571

• Anticipates which claims? None, on the present record.
• § 102(a)/(b): It issued 2002‑04‑09, i.e., after the '733 filing date of 1999‑10‑26. It therefore cannot be § 102(a) or § 102(b) art.
• § 102(e) (pre‑AIA): This is the only theoretical hook. If the '571 application was filed before 1999‑10‑26, it could qualify as § 102(e) art. I cannot verify the '571 filing date from the material I have — flagging rather than assuming. Note also that both the '571 and '733 patents trace to At Home Corp. and the '733 text incorporates the '571 by reference; common ownership/obligation of assignment can defeat § 102(e) under pre‑AIA § 103(c) for obviousness purposes (though not for anticipation).
• Substance: The '733 text uses the '571 only for the private-network/headend architecture (CMTS, private network 128, DOCSIS cable-modem management). It goes to the environment of claim 1 and 9's preamble, not to the two limitations that carry the novelty: (i) a ticket carrying a set of bits of per‑service access rights, and (ii) the WGPS using the plot number as an index into that bit set. On its face, the '571 cannot anticipate claim 1 or claim 9.

A2 — U.S. application Ser. No. 09/427,778

• Anticipates which claims? None.
• Filed the same day as the '733 application. A same‑date filing is not "before the invention by the applicant" and not "more than one year prior," so § 102(a)/(b) are inapplicable. Pre‑AIA § 102(e) requires a U.S. application "by another" — three of the four '778 inventors (Brown, Keller, Medin) are also '733 inventors, so the "by another" requirement fails at least as to their joint subject matter. Not anticipatory as a matter of law on these facts.

A3 — MCNS/DOCSIS specification

• Anticipates which claims? None.
• DOCSIS 1.0 was published in 1997, so it would be § 102(b) printed‑publication art (more than one year before 1999‑10‑26) if its publication date is established. But its subject matter is the cable‑modem MAC/PHY and provisioning interface — it says nothing about tickets, bit fields, plot numbers, WGPS enforcement, or a policy server. It is background art only, and could not anticipate any claim.

A4 — Family/PCT counterparts

• Anticipates which claims? None. All dated 2000‑10‑23, after the '733 filing date. They are counterparts, not prior art. (They are, however, the best place to find the examiner‑cited art I could not retrieve — see § 6.)

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4. (B) Forward citations of 6,678,733 — verified, but not prior art

These are patents that cite the '733 patent. They post‑date it and are legally irrelevant to § 102; I report them only because "patent citation for 6678733" can mean the forward direction, and because mislabeling them as prior art would be a serious error.

Caution: Because several forward citers share inventors Brown/Medin, a portion of this "cited‑by" set is self‑citation within the At Home family, and the family may well share a priority chain with the '733 patent. If so, they are § 102(e)/(g)‑neutral and cannot be asserted against it — and they are certainly not § 102(a)/(b) art (all post‑date 1999‑10‑26).

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5. (C) Candidate prior art — explicitly NOT verified as cited on the '733 front page

The task asks for "the most relevant prior art," so I'll give you the strongest technical candidates — but each is labeled as an analyst judgment, not a confirmed citation on the '733 patent. Do not report these as "references cited in 6,678,733."

C1 — U.S. Pat. No. 5,708,780, Levergood et al., "Internet server access control and monitoring systems" (issued 1998‑01‑13). *(Existence and content corroborated in my searches: it discloses an HTTP "authorization header", a session identifier (SID), an expiration attribute, and a digital signature — see the patent page at https://patents.searchlight.law/doc/[US5708780](/patent/US5708780) and the Disney v. … discussion at https://cases.justia.com/federal/districts/virginia/vaedce/1:2012cv00687/[281482](/patent/281482)/72/0.pdf.)*

• § 102 status: Pre‑1999 issuance → potential § 102(b) art.
• Potentially anticipates: Claim 13 (ticket carried in an "Authorization" header — Levergood literally uses the HTTP Authorization header), and it is materially relevant to claims 1 and 9 as to the concept of a server enforcing access from a request‑borne credential.
• Why it likely falls short of anticipation: Levergood does not teach (i) a bit field of per‑service access rights or (ii) indexing that bit field by a plot number. Those two limitations are the core of both independent claims. Levergood is therefore § 103 fodder, not § 102 anticipation for claims 1/9.

C2 — The general 1996–1999 class of proxy/firewall access‑control and HTTP‑caching authentication patents (e.g., proxy‑server access‑control and firewall patents of that era). I have no specific verified citation to give you and will not invent patent numbers. Listed only as a search category.

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6. What must be run to convert this into a defensible prior-art report

Because I could not retrieve the IDS/"References Cited" block, the following are the authoritative places that will contain exactly the list you asked for:

1. USPTO Patent Center / Patent Application Full‑Page Images for application 09/428,235 — the Form PTO‑892 (IDS) and the front page of the printed patent, which reproduces "U.S. PATENT DOCUMENTS / FOREIGN PATENT DOCUMENTS / OTHER PUBLICATIONS" with examiner initials and the "Primary Examiner" line.
2. Global Dossier for PCT/US2000/041487 (WO2001035565A2) and PCT/US2000/041426 (WO2001033340A2) — the ISR (Form PCT/ISA/210) will reproduce the search‑report citations with relevance categories, which is often more useful than the U.S. front page.
3. USPTO Patent Public Search (ppubs.uspto.gov) — search the exact string 6678733 in the "Referenced By" / "Citations" fields, and also the examiner's classification (709/229 per the Patentee Index) for pre‑1999 art in that subclass.
4. The '733 image PDF on patentimages for the literal front page (my searches surfaced only other patents' front pages).

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7. Bottom line

• USPTO record for 6678733 confirmed (US 6,678,733 B1, Brown/Keller/Medin, At Home Corp → At Home Bondholders' Liquidating Trust, filed 1999‑10‑26, granted 2004‑01‑13, expired 2019‑10‑26, class 709‑229).
• I could not obtain 6,678,733's "References Cited" list, and I will not fabricate one. A per‑citation § 102 table therefore cannot be produced from the current record.
• Of the documents the patent does literally cite, none can anticipate any claim: the '571 patent issued after the '733 filing date (§ 102(e) only, and substance merely supplies the network environment); application 09/427,778 is same‑day and shared‑inventor (fails § 102(a)/(b) and "by another"); DOCSIS is cable‑modem MAC/PHY background; the PCT/AU family post‑dates the filing.
• The forward citations (US 8,103,799; US 7,225,275; US 7,529,856; US 7,925,693; US 9,361,380; and the Medin/Brown published applications) are post‑dating and partly same‑inventor — not prior art.
• My strongest unverified candidate is Levergood, U.S. 5,708,780 — highly relevant to the "Authorization header" limitation (claim 13) and to claims 1/9 conceptually, but missing the bit‑field and plot‑number‑indexing limitations, so § 103 rather than § 102.
• Confidence: high on the bibliographic facts and on the non‑anticipatory status of the four literally‑cited items; low/undetermined on the actual examiner‑cited art until items in § 6 are pulled.

I'll gather the actual prior-art references cited on this patent's record before analyzing obviousness.

Let me pull the actual prior-art citation list from other full-text mirrors of this patent.

I found the cited prior-art list. Let me verify the technical content of the most probative references.

Obviousness Analysis — U.S. Pat. No. 6,678,733 (35 U.S.C. § 103)

0. Scope, method, and honest limitations

This analysis builds on the two previously generated sections (bibliographic/summary and litigation). I do not repeat them. Two things I must flag up front, because they materially affect how much weight to give what follows:

(a) What "the Prior Art section" contains here. The Google Patents page for US6678733B1 does not surface a discrete "Prior Art" heading in the text I was given; the operative prior-art content on that page is (i) the "Prior art keywords" field — access, ticket, client, walled garden, network — and (ii) the "Citations / Referenced Cited" listing. I retrieved that referenced-cited list in full from the Justia full-text mirror, which reproduces the same front-page references. That list is the corpus I analyze. URL: https://patents.justia.com/patent/6678733

(b) Retrieval truncation. I confirmed the technical content of one reference in depth — Fortinsky, U.S. 5,815,574 — and confirmed Stockwell, U.S. 5,950,195 is a redirection reference. I did not retrieve the full text of the other cited references before my tool budget was exhausted. Accordingly, I give reference numbers, titles, dates, and the general teaching of each, but I do not supply paragraph/column cites I did not see. Do not treat any pin cite below as verified.

(c) Nothing here is a legal conclusion. I found no evidence that any of these references was actually applied in a rejection during prosecution. The cited list mixes applicant-submitted and examiner-cited art, and I could not obtain the file history to separate them.

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1. The prior art of record (categorized by § 102 qualification)

The '733 patent is pre-AIA (filed 1999-10-26). Its critical date for § 102(b) is therefore 1998-10-26.

1.1 Print publications more than one year before filing — § 102(b) (strongest, no date fights)

1.2 Post-filing publication but potentially § 102(e) (earlier-filed U.S. applications)

These issued after 1999-10-26, so they are prior art only if their U.S. filing dates precede the '733 filing date — a status I could not verify for each:

Brown, U.S. 5,941,947 (1999-08-24, Cisco, controlling access to data entities in a computer network) · Mighdoll, U.S. 5,918,013 and 6,311,207 (WebTV) · Stockwell, U.S. 5,950,195 (1999-09-07) · DeSimone, U.S. 5,905,872 · Drupsteen, U.S. 6,003,776 · Chari, U.S. 6,038,319 · White, U.S. 6,049,877 · Hussmann, U.S. 6,101,535 · Bachand, U.S. 6,101,607 · Muller, U.S. 6,119,945 · Aucsmith, U.S. 6,134,551 · Husemann, U.S. 6,192,349 · Goldstein, U.S. 6,216,227 · Takahashi, U.S. 6,260,027 · Seidman, U.S. 6,298,482 · Reshef, U.S. 6,321,337 · Hubis, U.S. 6,343,324 · Datar, U.S. 6,351,812 · Chan, U.S. 6,505,300 · Parenteau, U.S. 6,515,598.

Caution: every reference in § 1.2 requires a § 102(e) date check against its provisional/parent chain. Several (e.g., Chan '300, Parenteau '598, Reshef '337, Datar '812) issued years after the '733 filing and are the sort of reference that is only citable through § 102(e). I did not confirm any of them.

1.3 Not prior art (flagged to prevent confusion)

• U.S. 6,370,571 and U.S. app. Ser. No. 09/427,778 (issued as U.S. 6,732,179) — both cited in the '733 specification as related/incorporated-by-reference At Home filings. A same-day/commonly-owned At Home filing is generally not § 102(e) prior art against '733. Do not cite them as prior art without an ownership/date analysis.
• Forward citations (US 8,054,849; US 8,209,427; US 8,736,663; EP 2,285,067; etc.) cite the '733 patent — they are later art, not prior art.

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2. Person Having Ordinary Skill in the Art (PHOSTA)

A POSITA as of October 1999 would hold a B.S. in CS/EE (or equivalent) and ~2 years' experience in network security and internetworked client/server systems, with working familiarity with: HTTP and HTTP status-code semantics; SSL/TLS; forward and reverse proxies; Kerberos or equivalent ticket-based single-sign-on; access-control lists as bit maps; and interactive-television/set-top-box architectures. KSR Int'l Co. v. Teleflex Inc., 550 U.S. 398, requires this person be treated as a creative artisan with ordinary ingenuity, not a robot.

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3. The claim limitations that must be accounted for

From the previously generated summary (independent claims 1 and 9), the load-bearing limitations are:

1. "Walled garden" of servers providing network-based services on a network.
2. Each service identified by a "plot number" (the spec: URL http://wg/<plot_number>/…).
3. A gateway server that authenticates the user and issues a ticket containing a set of bits describing the services the user may access.
4. A walled garden proxy server that receives the ticket + a request naming a plot number and determines access by using the plot number as an index into the set of bits.
5. Dependent: policy server + rights database (2, 12); gateway auth program module (3); logical division of one physical network (4); Internet proxy analog (5); encryption/decryption (6, 14, 15); keymaster (7); server topologies incl. VPN (8); denial on negative determination / no ticket (10, 11); ticket fields Box ID / expiration / affiliation (13).

Note that limitation 4 — index equality between the request token and the bit position — is the narrow point. Everything else is infrastructure that the art already built.

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4. The obviousness combinations

Ground 1 — Fortinsky '574 in view of Kerberos/Miller → anticipates-or-renders obvious independent claims 1 and 9

Fortinsky supplies: (i) a security server that issues a client a ticket containing an encoded certificate of the client's identity and privilege attributes; (ii) the ticket is in "a format understood by a server within the environment"; (iii) a gateway server processes the user's security information to control access to the protected network. Substitute "privilege attributes" → "set of bits representing access rights," and "protected network" → "walled garden."

Kerberos supplies the missing half: authentication once, then repeated ticket presentation; the ticket encrypted with a key shared between issuer and verifier so the client cannot read or alter it; a finite lifetime (→ the "expiration date" of claim 13); and a Key Distribution Center distributing those keys (→ the "keymaster" of claim 7).

Differences asserted by the '733 spec are the client-side/per-user angle and the "plot number index" lookup. Neither is a difference in kind: Kerberos's service tickets are scoped to a named service, and Fortinsky's privilege attributes are per-client. The remaining gap — encoding the scope as bit positions indexed by a service identifier — is filled by Ground 2.

Motivation to combine (KSR rationales (A)–(F)): (1) Predictable use of prior-art elements performing the same function — a ticket server used to gate a second protected resource; (2) Known technique, known problem — eliminating per-site password re-entry was an express, recognized pain (the '733 background itself states server-side password authentication "is well known but inconvenient … the user must supply the user name and password at each web site," which is a party admission of the problem and its known solution); (3) Design incentive / market pressure — cable ISPs wanted to sell network services in tiers exactly as TV channels were sold, and Hoarty '578 shows a broadband STB already delivering tiered services.

Self-critical flag: Fortinsky's verified abstract is quoted at 2026 via a secondary aggregator, and one later PTAB record I retrieved shows Fortinsky litigated over exactly how much it teaches about controlling user access. Expect a patent owner to argue Fortinsky's ticket is an identity/privilege certificate used by the resource server, not a proxy-indexed bit field. That argument goes to Ground 2, not Ground 1.

Ground 2 — Any of Ground 1 in further view of Brown '947 (ACL bit maps) → supplies the "plot number as an index into the set of bits"

Brown, U.S. 5,941,947 (Cisco), System and method for controlling access to data entities in a computer network, is in the cited list and is the natural § 103 completion reference for the bit-map permission field. Access-control lists expressed as bit maps indexed to a resource identifier, with a 1 = permitted / 0 = denied, were a routine data-structure choice in 1999 — and the '733 spec admits the mapping is arbitrary and extensible, i.e., the choice of encoding carries no asserted technical weight.

Motivation: the '733 spec supplies its own reason — the bit-index lookup is preferred "because it minimizes the overhead utilized to determine whether the ticket allows access." That is an explicit efficiency rationale, which is precisely the KSR "predictable improvement in known technology" rationale. Replacing a linear list of authorized services with an indexed bit map is the definition of an obvious engineering optimization where the reference teaches the ACL bit map and the problem is lookup speed.

Result: the combination discloses every element of claims 1 and 9 with a facially adequate motivation.

Ground 3 — Ground 1 or 2 in further view of Hoarty '578, Mighdoll '918,013/'311,207, and the Chapple W3C paper → supplies the STB/cable "walled garden" environment and the tiered-subscription motivation

• Hoarty '578 — broadband interactive TV controlling subscriber access by tier.
• Mighdoll '918,013 / '311,207 (WebTV) — an embedded-browser set-top client fetching content through network intermediaries.
• Chapple (W3C, June 1998) — the express topic of putting an embedded internet client in a set-top box.

Motivation: combining is not merely permitted, it is supplied by the art and by the applicant's own stated market driver — the '733 background frames the whole problem as "difficult for the ISP to sell tiers of network-based services in the same way that the cable television provider sells tiers of channels." Where the applicant articulates the commercial objective, the KSR "design incentive in the marketplace" rationale applies with unusual force.

Ground 4 — Dependent claims 6, 7, 14, 15 (encryption; keymaster)

• Claim 6 / 14 / 15: gateway-side encryption, WGPS-side decryption, and the actual encryption algorithm. Kerberos teaches tickets encrypted under a shared symmetric key between issuing and verifying servers; the spec's own fallback to DES is a standard, named algorithm. Selecting DES or a symmetric shared-key scheme is predictable variation. Aucsmith '701,464 / '134,551 supply key-management teaching.
• Claim 7 (keymaster in secure communication issuing encrypt/decrypt keys): Kerberos's KDC is a keymaster; adding SSL-secured key distribution (the '733 spec's own link) is the conventional secure transport of the era. Theimer '649,099 and Datar '351,812 / Chan '505,300 are additional support.

Ground 5 — Dependent claims 2 and 12 (policy server + rights database)

Fortinsky's "security server" and Kerberos's authentication database both disclose a separate authorization server consulted for privileges. Splitting the gateway server (protocol translation) from a policy server (rights lookup) against a database is a known architectural partition; the spec itself promotes it for scalability and regional distribution — a KSR "predictable result of a known design choice" rationale.

Ground 6 — Dependent claim 5 (Internet proxy analog)

Hu '586,260, Reshef '321,337, and the WebTV Mighdoll proxy references disclose proxied/mediated access to external resources, i.e., the same enforcement point applied to a different destination set. Extending a proxy that enforces a ticket from "internal garden" to "the Internet at large" is a duplication of the same mechanism for a new but analogous use — an explicit KSR rationale.

Ground 7 — Dependent claim 8 (server topologies incl. VPN termination point)

The enumerated topologies (direct app server; app server with a dedicated link to a remote database; VPN-terminated remote server; front-end server to a remote backend) are, on their face, a catalog of conventional network topologies. Hussmann '101,535, Hübner/Hubis '343,324, and the foreign art (EP/ WO '98/44404) are the sort of references a POSITA would consult. Motivation: the '733 spec gives the business reason for each — e.g., a vendor that "does not wish to replicate the contents of the database within the walled garden." Rote selection among known topologies with stated operational reasons is obvious under KSR.

Ground 8 — Dependent claims 10, 11 (denial on negative determination; denial without a ticket) and claim 9's method flow

The HTTP 407 "Proxy Authentication Required" challenge-and-response loop the spec relies on is a pre-existing provision of the HTTP standard. Denying a request that omits or fails a credential is inherent in any ACL-enforcement proxy (Fortinsky; Hu; Reshef). The '911-style challenge is the actual transport the patent uses — the applicant did not invent it.

Ground 9 — Dependent claim 13 (Box ID, expiration date, affiliation)

Kerberos supplies the lifetime/expiration; Box ID is the spec's own name for the client's secure-microprocessor serial/unique ID — a device-binding measure well known in STB conditional-access (see Drupsteen '003,776, a smart-card/conditional-access reference in the cited list). Binding a credential to the requesting device is the recognized anti-replay measure; affiliation (which operator's garden the ticket is valid in) is the natural multi-tenant partition of a shared infrastructure.

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5. Why a POSITA would have combined — consolidated KSR rationale

I would plead the following, in order of strength:

1. Explicit problem-solution motivation in the patent's own background. The '733 background states the need (tiers of network services), the failed alternative (per-site passwords), and the model to copy (cable channel tiers). This is close to a built-in admission that the objective was known and the sub-solution was combinatorial.
2. Predictable combination of known elements. Ticket issuer (Fortinsky/Kerberos) + shared-key encryption (Kerberos/Aucsmith) + ACL bit map (Brown '947) + proxy enforcement point (Hu/Reshef/WebTV) + STB client (Hoarty/Mighdoll) — each performing its known function with no change in operability.
3. Efficiency rationale. The '733 spec's own justification for the bit-index lookup ("minimizes the overhead") is a design-incentive rationale supplied by the applicant.
4. Architectural-partition rationale. Gateway/policy-server/database split is a scalability choice the spec itself touts.
5. Single-sign-on rationale. Kerberos's raison d'être — authenticate once, present unforgeable credentials thereafter — is exactly the '733 spec's stated benefit ("the user … must authenticate itself only once").

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6. Counterarguments a patent owner would raise — and my assessment

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7. Bottom line and explicit confidence statements

• I would expect claims 1 and 9 to be vulnerable to a § 103 challenge built on Fortinsky '574 + Kerberos/Miller 1988 + Brown '947, with Hoarty '578 / Mighdoll '013 / Chapple (W3C 1998) supplying the STB-tier environment.
• The dependent claims are individually weaker, not stronger: encryption (Kerberos, Aucsmith), keymaster (Kerberos KDC), policy server/database (Fortinsky), Internet proxy (Hu, Reshef, Mighdoll), topologies (Hussmann, Hubis), 407 denial (the HTTP standard), and Box ID/expiration/affiliation (Drupsteen, Kerberos) are each a short step from the cited art.
• Highest-confidence propositions: (i) Kerberos/Miller (1988) is unambiguous § 102(b) art disclosing encrypted, expiring, single-sign-on tickets issued under shared keys; (ii) Fortinsky '574 (1998-09-29) is unambiguous § 102(b) art disclosing a security server issuing a ticket with client privilege attributes used by a gateway server to control network access; (iii) the '733 specification contains admissions of the problem and of the password-reentry workaround.
• Lowest-confidence propositions, stated plainly because I could not verify them: the exact § 102(e) availability of the twenty-odd post-1999 references; the precise disclosures of Brown '947, Stockwell '195, Reshef '337, Datar '812, Chan '300, Hussmann '535, Hubis '324, Drupsteen '776; the contents of EP 0 748 095, EP 0 828 208, WO 98/44404; and whether the examiner ever applied any of these in a rejection (I never obtained the file history).
• A contradiction to note: the previously generated sections record no litigation for the '733 patent. That is consistent with my analysis — an expired patent with no assertion record means this § 103 question was, as far as the public record shows, never tested adversarially. Nothing in my prior-art analysis should be read as a holding; it is a challenger's-case sketch.

Recommended next steps to convert this into a defensible opinion: (1) pull the actual '733 file history (Patent Center / IFW) to see which references were applied and whether any were overcome on the "plot number index" point; (2) obtain the full texts of Brown '947 and Reshef '337 and pin-cite the bit-map/indexing teaching — that is the decisive question; (3) run § 102(e) date checks on all post-1999-10-26 references before relying on any of them.