US RE48088

I'll search for authoritative information on RE48088 before summarizing.

US RE48,088 E1 — Analyst Summary

Source of record: Google Patents full text (fetched 2026-09-29), plus USPTO/PTAB filings, Stanford NPE Litigation Database, Unified Patents (Patroll/Portal), and PACER-derived docket aggregators. The claim text of RE48,088 was not in the truncated full-text I was given (the document ends mid-Description), so the claim overview below is grounded in the patent's abstract, specification, and the closely related sibling reissue RE46,637 — see the uncertainty note at the end.

Bibliographic data

Abstract (verbatim, as published)

"Anonymous voice communication between a first station and a second station is facilitated by providing an interface that allows input of a transaction specification from at least one of the first and second stations. A reference code associated with the transaction is generated, there being a defined relationship between the reference code and the address of the second station for voice communication. The reference code is supplied to the first station, and a voice communication request and the reference code are received from the first station. The reference code is used to recover said address and a channel for voice communication is opened between said first and second stations. Voice communication can thereby be established between the first and second stations without providing the address of the second station to the first station. Client (e.g., a device, a station, or an application) for accessing an Internet-based service that data mines user information is herein disclosed and enabled. …"

Note the abstract is a two-part abstract: the first half is inherited from the original anonymous-voice-communication invention (RE43,181 / RE46,637 lineage); the second half (beginning "Client … for accessing an Internet-based service that data mines user information") was added in the reissue and corresponds to the newly added client/data-mining claims.

Plain-language overview of the independent claims

The independent claim set addresses two sides of the same system, plus apparatus/software counterparts. Based on the abstract, the specification, and the parallel claim set of sibling RE46,637 (where independent claim 38 was asserted in Flexiworld v. Indeed and dependent claims 39–42 and 52–55 were also asserted), the independent claims fall into these groups:

1. Controller / service-side method claim — A method in which a controller obtains one or more transaction specifications over the Internet associated with a second party (e.g., an employer or expert); the controller data mines information on the second party based at least partly on data collected from a history of transactions; the controller creates a proposed transaction specification for the first party that uses that mined data; the controller generates a reference code having a defined relationship to the second party; supplies the reference code to the first party; receives a connection/communication request from the first party that employs the reference code; and then makes a connection between the first and second parties without requiring the first party to have provided the transaction specification (anonymity/relief-from-specification element carried over from the original invention).

2. Client / user-side claim (device, station, or application) — A client (implemented as a device, station, or downloadable/executing application) for accessing an Internet-based service that data mines user information; the client opts in (or out) of having the service match the user against other users; the client receives, for presentation to the user, a proposed transaction between the user and another party that is based at least in part on data mining the user's transaction history; the client receives or displays a reference code related to the proposed transaction (the reference code may be text, image(s), video(s), audio, and/or a communication link, and the proposed transaction may be an advertisement); and the client sends a communication request to the service employing that reference code.

3. Apparatus / system and (likely) article-of-manufacture or application claims — Hardware/software counterparts reciting the controller with means for negotiating a transaction specification, generating the reference code, receiving the request and reference code, recovering the second party's address from the reference code, and opening the communication channel without disclosing that address to the first party; and client-side equivalents.

The through-line of the reissue: take the original 2000-era "anonymous scheduled voice connection via a transaction-specific reference code" disclosure and apply it to a modern data-mining / recommendation / advertisement matching service (the industry application the patentee later pursued). The reference-code mechanism is what preserves the first party's anonymity while the service brokers the connection.

Litigation and docket status

• Flexiworld Technologies, Inc. v. Indeed, Inc., No. 1:24-cv-01254 (W.D. Tex., filed 2024). RE48,088 was among the asserted patents, alongside related Flexiworld patents (RE46,637 and RE48,066 appear in the complaint analysis). Unified Patents described the asserted technology as "a device that, by executing software, can opt into suggestions for connecting with another party … a controller unit matching the first party's data with the second party's specifications." An amended complaint was filed 2025-01-17; Indeed moved to dismiss on 2025-02-14. Per the public bio of Indeed's counsel (Gibson Dunn), Judge Albright granted dismissal with prejudice, holding all four asserted patents patent-ineligible under 35 U.S.C. § 101 prior to claim construction and discovery. (This is a first-of-its-kind § 101 ruling by Judge Albright as characterized by counsel.) I did not retrieve the docket entry text of the order itself, so treat the precise disposition wording as second-hand.
• Unified Patents – Patroll prior-art contest: a $2,000 prize contest opened 2024-12-04 and closed 2025-01-04 targeting at least claim 52 of US-RE48088-E1 (claim chart required; AI-assisted charting via Pearl).
• PTAB: an IPR petition (PTAB petition 1553926, Lexmark-related family activity) lists challenges to independent claims 1, 18, 27, 37, 42, 47, and 50 and numerous dependents including 52, 57, and 61, using Keeney alone and Keeney + Vatland. Caution: I could not confirm from the retrieved excerpt whether that particular claim listing is for RE48,088 or for a sibling reissue in the same family, so do not rely on it as an authoritative claim listing for RE48,088.
• Flexiworld Technologies, Inc. v. TCL Electronics Holdings Ltd. et al, No. 2:2026-cv-00229 (E.D. Tex., filed 2026-03-20, Judge Rodney Gilstrap). This is an active 2026 Flexiworld filing. I could not confirm from the retrieved docket that RE48,088 is among the patents asserted in that case — the docket summary did not list patents-in-suit.

CAFC 2026 dockets

I found no Federal Circuit appeal or 2026 CAFC docket activity specifically identifying RE48,088. Given the with-prejudice § 101 dismissal in Flexiworld v. Indeed, an appeal would be plausible, but I have no authoritative record of one. I will not speculate on a docket number.

Explicit uncertainties

1. Claim text: The authoritative full text supplied to me was truncated before the claims, so I could not read the literal independent claim language of RE48,088. The overview above is reconstructed from the abstract/specification and the sibling RE46,637 claim structure (which shared the same specification). Independent claim numbers for RE48,088 itself were not confirmed.
2. Priority date discrepancy: Google Patents shows 2000-09-05; Unified Patents' portal shows 2000-09-04.
3. Indeed disposition: the § 101 dismissal-with-prejudice characterization comes from defense counsel's public bio, not from the order text.
4. TCL 2026 case: RE48,088's inclusion among the asserted patents is unverified.
5. PTAB claim listing: verified as a family-level petition excerpt but not confirmed as directed to RE48,088.

If you need the literal claim language and confirmed independent-claim numbering, the definitive source is the issued reissue patent's claim section (USPTO Patent Center / PatentCenter for RE48,088, application 15/839,718) or the Google Patents claim tab at https://patents.google.com/patent/USRE48088E1/en — I'd recommend pulling that before using the claim overview in any chart or opinion.

I'll research litigation involving US patent RE48088. Let me search multiple sources.

Found a lead. Let me verify the specific case and check additional sources.

Let me check the current status of the Indeed case and any related proceedings.

Litigation Involving U.S. Patent No. RE48088

Bottom line

My searches of patent-litigation databases (Stanford NPE Litigation Database, Justia Dockets, RPX Empower, Docket Alarm, AI Lab / ExParte litigation trackers, Unified Patents' litigation and Patroll portals) located exactly one court litigation in which U.S. Patent No. RE48088 ("RE48088") is identified as an asserted patent. I found no ITC § 337 investigation and no CAFC appeal docketed specifically for RE48088. I did not include results for the many other Flexiworld patents/reissues that surface in searches (e.g., RE42,725, RE41,532, RE46,637, RE48,066, RE41,882, RE41,689, RE42,828, RE41,416, RE41,487, and various utility patents), since those are different patent numbers.

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Case 1 — Flexiworld Technologies, Inc. v. Indeed, Inc.

Key docket activity

• Oct. 18, 2024 – Complaint filed; jury demand by Flexiworld; Civil Cover Sheet and AO 120 (Patent) form filed.
• Oct. 23, 2024 – Indeed served; original answer deadline Nov. 13, 2024.
• Nov. 1–4, 2024 – Indeed's unopposed motion to extend answer deadline; granted by Judge Pitman, resetting response date to Dec. 13, 2024.
• Dec. 13, 2024 – Indeed filed a Motion to Dismiss under Fed. R. Civ. P. 12(b)(6); Rule 7.1 corporate disclosure statement filed; pro hac vice motion for Wendy W. Cai (counsel for Indeed, with Brian M. Buroker).

Outcome / current status

Unresolved / uncertain. The Justia docket (last retrieved Dec. 13, 2024) ends at the filing of Indeed's Rule 12(b)(6) motion, so the disposition of that motion is not reflected in the sources I could retrieve. One litigation-tracking aggregator shows the case with a status of "Closed" and a sector tag of "Reexam/Aband.", but I could not corroborate a termination date — the Stanford NPE Litigation Database entry for this case lists no termination date. Accordingly, I cannot state with high confidence whether the case was voluntarily dismissed, dismissed on Indeed's motion, stayed pending reexamination, or remains pending. This should be verified against PACER for case 1:24-cv-01254.

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Related proceedings that are not court litigation (for context, not responsive to the litigation question)

• USPTO ex parte reexamination of RE48,066 (not RE48088): On May 23, 2025, Unified Patents filed an ex parte reexamination against U.S. Patent RE48,066 — a different reissue patent — which Unified states "has been asserted against Indeed." Because this targets RE48,066 and not RE48088, it is not a RE48088 proceeding.
• Unified Patents "Patroll" prior-art contest on RE48088: A crowdsourced prior-art bounty seeking art on at least claim 52 of US-RE48088-E1 ran Dec. 4, 2024 – Jan. 4, 2025 ($2,000 prize; winner announced; per Unified, the patent "has been asserted against Indeed"). This is a prior-art search contest, not litigation, but it corroborates that RE48088's only known assertion is against Indeed.

Caveats on completeness

• The Stanford NPE Litigation Database entry for RE48088 lists only the single Indeed case, matching my other searches.
• I did not obtain a full PACER docket or a CAFC docket specifically for RE48088; if RE48088 was appealed or transferred, that would not appear in the sources retrieved. PACER and the Unified Patents litigation portal (portal.unifiedpatents.com/litigation) should be checked directly to confirm the current status of 1:24-cv-01254 and to rule out any post-December 2024 developments.
• If no other case exists, the answer to your question is: one known litigation (Flexiworld v. Indeed, 1:24-cv-01254, W.D. Tex.), with all other Flexiworld suits I encountered involving different patent numbers.

I'll verify the canonical "no PTAB proceedings" result against live sources before writing.

No PTAB hits for RE48088 itself. Let me run targeted confirmation searches, including on the parent reissue and any Indeed-challenger activity.

Let me check for any 2025 follow-on petition from Unified after its RE48088 prior-art contest.

Proceedings overview

Zero AIA trial proceedings on file for U.S. Pat. No. RE48088. The canonical structured source in this prompt (USPTO Open Data Portal ingest) returns no IPR, PGR, or CBM naming this patent, and my independent web searches (Unified Patents portal/litigation tracker, Docket Alarm PTAB, Stanford NPE database, PTAB E2E-adjacent document searches, and general queries on "RE48088" IPR/PGR/PTAB) surfaced no petition, no institution decision, no Final Written Decision, and no Federal Circuit appeal keyed to RE48088.

Breakdown by status: active 0 / claims invalidated 0 / claims sustained 0 / settled 0 / institution denied 0.

Bottom line for a defendant: RE48088 is not "hardened" and not "killed" — it is untested at the Board. There is no FWD to cite, no canceled claim to hold up as a sword, and no PTAB claim-construction or priority ruling you can borrow. But there is also no petitioner estoppel blocking you, no Fintiv/§ 314(a)-style refusal on this patent, and no adverse panel history. The invalidity fight is greenfield: whoever files first gets to pick the art and frame the priority dispute. The only real signal from the PTAB ecosystem is that a defensive aggregator (Unified Patents) has already crowdsourced prior art on claim 52 — the implication being the industry views RE48088 as challengable but simply hasn't filed yet. That cuts both ways: art generation is done or in progress, and a first-filer IPR on claim 52 (and claims 38–42) is plausible and should be monitored.

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No proceeding to report

There is no {PROCEEDING_NUMBER} to list. Per the operating rules, I will not invent one. The absence is corroborated across sources (see links below).

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Adjacent activity that is NOT a RE48088 proceeding (do not confuse these — Flexiworld's portfolio generates a large volume of near-miss hits)

These are frequently returned alongside RE48088 in searches and are worth separating clearly:

Adjacent prior-art generation on RE48088 specifically (not a Board proceeding): Unified Patents' Patroll contest "Flexiworld Technologies: US-RE48088-E1 (Facilitating Connections Between Parties Through the Internet)" ran 2024-12-04 → 2025-01-04, offering $2,000 for prior art on at least claim 52 of RE48088, with claim charts required and previously-cited prosecution art excluded. Status on the contest page: "Finished / Winner Announced." Unified subsequently published the winning art (insights post dated 2025-03-29, "$1,500 Awarded for Flexiworld Technologies Communication Patents Prior Art"). Source: https://patroll.unifiedpatents.com/contests/5M4duRZBqwxMYnFDP and https://www.unifiedpatents.com/insights/2025/3/29/1500-awarded-for-flexiworld-technologies-communication-patents-prior-art

Interpretation: art exists, was vetted, and was publicized — but no follow-on IPR against RE48088 appears in any source I could retrieve as of 2026-09-29. That gap (contest closed early 2025, no petition ~20 months later) is itself notable and may reflect (a) a discretionary-denial calculus against the live W.D. Tex. case, (b) settlement/licensing movement in Flexiworld v. Indeed (1:24-cv-01254), or (c) art that looked good in a chart but not good enough for an institution-ready § 103 theory. I cannot determine which — say so rather than assume.

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Strategic summary

Claim status. With zero PTAB proceedings, no claim of RE48088 is canceled, and no claim has been adjudicated sustained. Every claim — the asserted independent claim 38, dependents 39–42, and claims 52–55 identified in the prior litigation section — remains in the same legal posture it had on the reissue grant date of 2020-07-07: presumptively valid, never construed by the Board, never subjected to an institution decision. There is no "surviving claims" carve-out to report, because there is no PTAB narrowing.

Estoppel landscape. Because no IPR/PGR was ever instituted on RE48088, 35 U.S.C. § 315(e)(2) estoppel does not attach to this patent — not against Indeed, not against Unified, not against anyone. That is materially different from the sibling-patent picture: a petitioner that did institute (e.g., Unified in IPR2022-00775 on the '257 patent) is estopped as to that patent only; estoppel is patent-by-patent and does not "spill" onto RE48088. Practically, that means all prior-art grounds against RE48088 remain available to any party, including art in the same technical space that might have been raised or "reasonably could have been raised" in a hypothetical earlier challenge — there was no earlier challenge. The only soft constraints are (i) § 325(d) Advanced Bionics discretion if you recycle art the examiner already considered during reissue prosecution, and (ii) § 315(b) if you have been served with a complaint asserting RE48088 more than one year ago.

Pattern signals. (1) Same-petitioner pattern: there is no petitioner that has filed multiple IPRs on this patent — because there are none at all. (2) Aggregator presence: Unified Patents is in the chain, but so far only as (a) a crowdsourced prior-art sponsor on RE48088 claim 52 and (b) an ex parte reexam requester against the different RE48,066 reissue. Unified is clearly tracking the Flexiworld portfolio and has previously instituted against it on other patents (IPR2022-00775). (3) Patent owner behavior: Flexiworld has defended at the Board before, including by pressing RPI/standing and § 314(a) discretionary-denial theories against Unified, and by using expert declarations to shore up written description, priority, and § 101 against Roku. Expect the same playbook — and expect Flexiworld to elect to amend rather than simply defend if an IPR is filed, given the reissue history. (4) CBM window: RE48088 granted 2020-07-07, i.e., just before the 2020-09-16 CBM sunset. A ~2-month window existed in which a CBM petition could theoretically have been filed; none appears. (Whether RE48088 would even qualify as a "covered business method" patent is uncertain — it is a pre-AIA patent, so PGR was never available; only IPR and, briefly, CBM.) Flag this as an inference, not a verified fact.

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Recommended next steps

1. Do not represent to a court or client that RE48088 has been invalidated. It has not. If an adverse demand letter cites claims 38–42 or 52–55, there is no FWD to point to and no cancellation certificate to attach. The prior-art contest win is not a merits ruling by the Board and creates no estoppel.

2. Verify on the primary sources before relying on this. I could not pull a live PTAB E2E / Patent Trial & Appeal Board docket for RE48088 directly in this session. Confirm at:

   • PTAB E2E / PTAB Decisions: https://developer.uspto.gov/ptab-api/ and https://www.uspto.gov/patents/ptab/decisions
   • Unified Patents litigation/patent portal: https://portal.unifiedpatents.com/patents/patent/RE48088
   • Stanford NPE Litigation Database (independent corroboration that the only assertion is Flexiworld v. Indeed, 1:24-cv-01254, W.D. Tex.): https://npe.law.stanford.edu/patent/re48088
   • Google Patents "litigation"/family page: https://patents.google.com/patent/USRE48088E1/en

3. Pull the Patroll winning art now. It is public and was specifically charted against claim 52 by the contest winner. Link above (Unified insights, 2025-03-29). If you are a defendant, this is your starting § 103 theory; if claim 52 is asserted against you, that art is the most-developed invalidity position in the public domain for this patent. Note the contest rules excluded art previously cited during prosecution, so anything obtained through Patroll is presumptively "new" for § 325(d]/§ 311(b) purposes — a meaningful advantage.

4. Officer-of-the-court / deadline check. If you were served with an RE48088-based complaint more than one year ago, § 315(b) bars your IPR. Compute from the actual service date. If you are inside the window, the absence of any prior petition means you would be the first filer, controlling the ground and getting no adverse-claim-construction heritage.

5. Watch the Indeed case for IPR-triggering events. The prior litigation section flags that Flexiworld v. Indeed showed a Rule 12(b)(6) motion (filed 2024-12-13) with unresolved disposition and at least one aggregator tagging the case "Closed / Reexam-Aband." If the Indeed case settled or was dismissed after the Patroll contest, the incentive for Unified or another aggregator to file on RE48088 may have shifted — and a 200-winner Patroll contest with no follow-on petition would then read as "art obtained, filing shelved," which is a nuance worth confirming on PACER for 1:24-cv-01254 before forming a defensive strategy.

6. Do not conflate proceedings. Multiple AIA trials exist against other Flexiworld patents (RE48,066 reexam; IPR2022-00775; Roku's IPRs; Lexmark's petition). None of them is RE48088, and none of them estops a RE48088 challenge. Any settlement or FWD in those matters should be read as portfolio-level pressure on Flexiworld, not as an adjudication of RE48088.

Confidence statement: I have high confidence that no AIA trial proceeding was on file for RE48088 as of the structured-data ingest, and that web-accessible sources show none as of retrieval. I have lower confidence as to whether a petition was filed very recently (last few months) but not yet indexed, and I could not resolve the current status of the parallel district court case that would most plausibly drive a future petition.

I'll research the assignment and ownership record for US RE48088. Let me search multiple sources.

Let me dig into the assignment records and the original patent's ownership history.

I found references to recorded assignments in Flexiworld's complaints (e.g., Reel/Frame 028733/0064; 042385/0202). Let me pin down the specific assignment for the '304 patent / RE48088 chain.

I've gathered what I can from the available sources. Note that I hit the tool-call limit before I could pull the raw USPTO Assignment Center reel/frame entries for this specific patent, so I flag verification gaps explicitly rather than fill them with guesses.

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Inventors

Both inventors are listed on essentially the entire Flexiworld patent family — the same two names recur across dozens of grants and reissues (e.g., US 10,126,991; US 11,096,056; US 10,846,031; RE41,416; RE41,487; RE41,532; RE41,689; RE41,882; RE42,828; RE42,725; RE43,181; RE46,637; RE48,066; RE48,088).

Unusual-pattern check — "all inventors departing within 12 months": Not present. The founders did not leave; they remained the named inventors on filings spanning 2000–2020 (the RE48088 line itself runs from the 2000 provisional to the 2017 reissue filing). This is the opposite of the pre-fire-sale departure pattern. One timing nuance: the underlying provisional (60/230,021) was filed 2000-09-05, whereas Flexiworld was reportedly founded in 2001, so at the provisional date the inventors may not yet have been employees of the assignee; by the 2001-09-04 nonprovisional (09/947,116) the company existed. I could not independently confirm an executed employment/assignment agreement date for the 2000 provisional.

Original assignee

Flexiworld Technologies, Inc. — the entity named on the issued parent patent and on RE48088 (Google Patents lists current assignee Flexiworld Technologies Inc.; Unified Patents' portal lists the assignee as "Flexiworld Tech Inc").

• Primary line of business: developer of "FlexiCore" pervasive/mobile wireless output technology — mobile printing, wireless device synchronization, and mobile content output. PitchBook: "IT Consulting and Outsourcing / Other Communications and Networking"; Crunchbase industry tag "Software."
• Did it ship a product embodying these claims? It was an early-stage startup (accelerator 2001; Series A 2002 ~$295K; Series A2 2006; ~$1.5M total raised) that obtained industry press attention (a 2002 Columbian article quoting Lexmark). Critically, Flexiworld's own pleadings admit it "has not made, offered for sale, sold, or imported a product that practices any of the Patents-in-Suit." So there is no evidence of a shipped commercial product embodying the anonymous-communication claims of RE48088.
• Current status: Not acquired, not dissolved, not (on any evidence I found) in bankruptcy. PitchBook shows it Private / formerly VC-backed, with a completed "2ndary – Private" transaction (March 2022) and continued activity. Crunchbase lists operating status "Active." It functions today primarily as a patent-holding and licensing/assertion entity — a repositioned failed startup rather than a going concern in the product sense.
• Litigation posture (context for the signals below): Flexiworld is a high-frequency plaintiff against large operating companies (Amazon, Roku, Lexmark, Xerox, Hisense, LG, Indeed, and others), and its complaints recite recorded assignments from Chang and Liu to Flexiworld (see next section). Stanford's NPE Litigation Database tags Flexiworld under the asserter category "Failed startup."

Assignment timeline

Honest finding up front: The RE48088 ownership chain shows no post-issuance assignment away from Flexiworld. RE48088 issued (2020-07-07) to Flexiworld Technologies, Inc., and Flexiworld remains the owner/assignee per every current source I checked (Google Patents legal events; Unified Patents portal). The reissue line inherits the original assignment rather than generating a fresh one. I was unable, within the search budget available, to retrieve the precise USPTO Assignment Center reel/frame for the inventors→Flexiworld assignment of the parent application (09/947,116 / US 7,099,304) — that is a verification gap, not a negative finding.

Documented assignment evidence for the family (from Flexiworld's own complaints — sibling patents, not RE48088):

• 028733/0064 — assignment of the '402 patent from inventors Chang and Liu → Flexiworld (cited in Flexiworld v. Hisense, W.D. Tex., Mar. 7, 2023). Context: founding/internal assignment.
• 042385/0202 — assignment of the '072 patent from inventors Chang and Liu → Flexiworld (cited in Flexiworld v. LG, E.D. Tex., 2025). Context: founding/internal assignment.

Because the two inventors are the named assignors on the whole family and Flexiworld is a single continuing assignee, the pattern is a single founding assignment per application line, with no intermediate NPE LLC, no securitization, and no transfer-to-asserter step. If the Assignment Center does show a RE48088-specific entry, it would almost certainly be a 2001–2002-era Chang & Liu → Flexiworld recording on the parent line; please verify the exact reel/frame directly rather than rely on the above.

Correspondent of record: I could not confirm the assignment correspondent for the RE48088 line. The recurring prosecution correspondent across Flexiworld grants is Chernoff Vilhauer LLP (listed as attorney/agent firm on Flexiworld grants such as US 10,846,031), and Nelson Bumgardner Albritton P.C. / Brent N. Bumgardner (Reg. No. 48,476) appears as Flexiworld's PTAB counsel. These are prosecution/litigation correspondents, not confirmed assignment correspondents — flagged so they are not mistaken for a shell-entity tell.

Timeline diagram

timeline
    title Ownership and Assertion of US RE48088
    2000 : Provisional filed by the two founders
    2001 : Flexiworld Technologies founded
    2006 : Parent patent 7099304 issues
    2012 : Reissue RE43181 issues
    2017 : Reissue RE46637 issues
    2020 : RE48088 issues to Flexiworld
    2024 : Sued Indeed in W D Tex
         : Patent term expires

NPE / troll-pattern signals

1. Shell-entity transfer — NOT PRESENT. No assignment from Flexiworld to any "IP / Licensing / Holdings / Ventures"-type LLC. The current owner is the original operating assignee itself. (No reel/frame evidence of a shell transfer exists in anything I retrieved.)

2. Known asserter in the chain — PARTIALLY PRESENT (as the originator, not an acquirer). No entry on the standard NPE lists (Acacia, Marathon, Intellectual Ventures, Wi-LAN/Conversant, Vringo, Pendrell, Round Rock, etc.). However, Flexiworld is itself a serial asserter and is entered in Stanford's NPE Litigation Database (category "Failed startup"); Unified Patents ran a Patroll contest on claim 52 of US-RE48088-E1 (Dec 4, 2024 – Jan 4, 2025) stating the patent "has been asserted against Indeed," and separately on US 7,099,304 (asserted against Skype). So the "known asserter" signal is satisfied by Flexiworld's own litigation program, not by a transferred-in NPE.

3. Repeat correspondent across the chain — UNCLEAR. No multi-link recording chain exists, so there is no recurring assignment correspondent to point to. Recurring prosecution counsel (Chernoff Vilhauer LLP) and PTAB counsel (Bumgardner/Nelson Bumgardner Albritton) span the family, but I could not tie either to the assignment recordings. Marked unclear rather than claimed.

4. Cascading transfers — NOT PRESENT. No chain of LLCs; no transfers at all in <24-month succession. The family instead shows continuation/reissue propagation (RE43,181 → RE46,637 → RE48,088; plus RE48,066, RE42,725, RE42,828, RE41,416, RE41,487, RE41,532, RE41,689, RE41,882), which is prosecution strategy, not ownership churn.

5. Pre-litigation transfer — NOT PRESENT. No assignment dated within 6 months before the Indeed suit (2024-10-18). Ownership was unchanged from ~2001 to suit.

6. Bankruptcy fire-sale — NOT PRESENT. No Chapter 7/11 filing or patent sale-in-bankruptcy found for Flexiworld; it remains active and litigating as of 2025.

7. Privateering — NOT PRESENT. Flexiworld asserts on its own behalf (it is the owner of record), not as a proxy asserting for a sponsoring operating company.

8. Defensive aggregator — NOT PRESENT. The chain does not terminate at RPX, AST, LOT, Unified, or OIN. Inverse signal absent.

Verdict

NPE — moderate confidence.

Justification: The ownership chain itself is clean — RE48088 issued in 2020 to Flexiworld Technologies, Inc., which is the original assignee and remains the owner, with the founding Chang-and-Liu assignment as the only ownership event and zero shell-entity, cascading-transfer, pre-litigation-transfer, or defensive-aggregator signals (contrast sibling reel/frames 028733/0064 and 042385/0202, which are straightforward founder→company recordings). The NPE character therefore does not come from an assignment-chain tell; it comes from the entity's assertion posture and admission: Flexiworld's own pleadings state it "has not made, offered for sale, sold, or imported a product that practices any of the Patents-in-Suit," it is catalogued by Stanford's NPE Database as a "Failed startup" asserter, it is a high-frequency plaintiff (including the sole RE48088 suit, Flexiworld v. Indeed, 1:24-cv-01254, W.D. Tex.), and Unified Patents has crowdsourced prior art on claim 52 of US-RE48088-E1. That is more than the required "1 strong or 2+ weak" signals, but it is not the classic acquired-portfolio NPE, so I stop at moderate rather than high confidence.

Verify at the USPTO Assignment Center: https://assignmentcenter.uspto.gov/ (search patent number RE48088) — and mirror index https://assignment.uspto.gov/patent/index.html. Confirm the inventors→Flexiworld reel/frame on the parent line (US 7,099,304 / appl. 09/947,116) and confirm there is no later assignment, which the current record strongly suggests.

Caveat on my own search: I could not retrieve the raw Assignment Center records within the tool budget, so the reel/frame values above are family-sibling citations from Flexiworld's complaints, not RE48088-specific confirmations. Treat the "no post-issuance assignment" conclusion as well-supported but pending direct USPTO confirmation.

I'll research the prior art references cited for US RE48088.

Let me search for the specific "References Cited" section and related prior-art documents.

Let me verify the IPR petition's target patent and find the actual cited references from the RE48088/7,099,304 front page.

US RE48,088 E1 — Prior-Art Analysis

Answer format note up front (read this first). The question asks me to work through patent citations for RE48088 (the "(56) References Cited" / "Patent Citations" list). I was only partly able to do that, and I want to be explicit about the gap rather than fill it in with guesswork:

• What I could retrieve: the USPTO bibliographic record for RE48,088 (reissue app 15/839,718), the PTAB/Patroll proceedings touching the family, and Google Patents' "Similar Documents" list for RE48088 as surfaced through the Unified Patents portal.
• What I could not retrieve: the literal (56) "References Cited" block printed on the face of RE48,088 (and of the original U.S. 7,099,304). The authoritative full text supplied to me is truncated mid-Description, before the front-page citation list and before the claims, and the search tool returned the "similar documents" data instead of the citation data.

So the table below is "most technically relevant prior-art candidates," not a verified list of references the examiner cited. I have flagged which are which. For a legal § 102 chart you must confirm against the (56) block via USPTO Patent Center (app 15/839,718) or the Google Patents "Patent Citations" tab.

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Correction to the previously generated sections (important)

The prior "Patent summary" flagged as uncertainty #5 whether a PTAB petition listing independent claims 1, 18, 27, 37, 42, 47, 50 (+ dependents 52, 57, 61) and relying on Keeney (U.S. 6,748,471) and Vatland (U.S. 6,091,507) was directed to RE48,088.

It is not. That petition (PTACTS petition 1553926, Lexmark) states the challenged patent is "the '233 patent" and that "Neither Keeney nor Vatland was before the Board during the 18-year long examination of the '233 patent." The '233 patent is U.S. 9,965,233 — a different Flexiworld patent (a wireless-printing/content patent, not the anonymous-communication reissue line). Therefore:

• Keeney and Vatland are NOT prior art cited against RE48,088. Do not carry them into an RE48,088 chart — that would be an auto-correct/attribution error of exactly the kind the operating rules forbid.
• This resolves (negatively) the earlier flagged uncertainty. The claim numbers in that listing (1, 18, 27, 37, 42, 47, 50 and dependents 52, 57, 61) belong to the '233 patent, not RE48,088 — so the earlier warning not to rely on them as an RE48,088 claim listing was correct.

The Patroll contest on RE48,088 (Dec 4, 2024 – Jan 4, 2025, $2,000, "at least claim 52") is real and is directed to the correct patent, but it is a crowdsourced prior-art hunt, and its rules state: "PRIOR ART THAT HAS BEEN PREVIOUSLY CITED DURING PROSECUTION WILL NOT BE CONSIDERED." That confirms a prosecution-cited set exists but does not reveal it.

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USPTO record for the specific number (confirmation)

No prior-art citations were returned for the number; only the "similar documents" set. A search on the exact string RE48088 also returned an unrelated Drosophila Genomics Resource Center fly stock (RRID:DGRC_1119368) and an unrelated U.S. 10,205,291 reference list — neither is the patent and neither was used.

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Most technically relevant prior-art candidates (from the RE48,088 "Similar Documents" set)

Source: Unified Patents patent portal for RE48,088 (portal.unifiedpatents.com/patents/patent/RE48088), which mirrors Google Patents' "Similar Documents," plus the Patroll page (patroll.unifiedpatents.com/contests/5M4duRZBqwxMYnFDP). These are algorithmic similarity results, not confirmed § 102 citations.

The through-line of the reissue (per the earlier summary) is: a client/device/application that opts into a service that data-mines the user's transaction history, gives the user a proposed transaction (optionally an advertisement) plus a reference code, and then brokers an anonymous connection using that code. The candidates split accordingly.

A. Candidates bearing on the "data mining / proposed transaction / advertisement" limitations (claims ≈ independent 38 and 52 groups)

B. Candidates bearing on the "reference code → recover address → anonymous connection" limitations (original-reissue claim group)

C. Lower-relevance "similar documents" (context only)

US 5,751,966; US 5,933,827; US 5,797,099; US 5,353,331; US 5,956,020; US 3,909,562 (all pre-1998) — general telephony/data networking. Note: several items in the same "similar documents" list (US RE41,532 "Apparatus, Methods and Systems for Anonymous Communication"; US 9,164,718; US 8,169,649; US 10,126,991; US 9,042,811; US 9,036,181; US 8,332,521; US 9,298,407; and the Flexiworld "smart phone / internet-pad" publications like US 2013/0095887, US 2015/0356564) are Flexiworld / Chang / Liu's own family — i.e., same-inventor / same-family material, not prior art available against RE48,088. Listing them as § 102 art would be an error.

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Bottom line

1. I could not verify the literal cited-reference (56) list of RE48,088 from the sources available in this session; the outputs above are similarity-ranked candidates, not citations. Treat every row as unconfirmed.
2. The strongest substantive candidates, if one must start somewhere, are US 6,266,668 (data mining + customized communication) and US 7,158,986 (personalized recommendations) for the data-mining/proposed-transaction limitations, and US 5,933,811 for the advertisement limitation — with US 6,694,003 for the reference-code/anonymous-connection limitations.
3. Keeney (6,748,471) and Vatland (6,091,507) are not RE48,088 art — they belong to the separate '233 patent IPR. This corrects the previously flagged uncertainty.
4. To produce a defensible § 102 chart, pull the (56) block for app 15/839,718 (RE48,088) and for U.S. 7,099,304 from USPTO Patent Center, since a reissue carries forward the original's citations and adds any new ones — my toolset could not reach that block.

I'll research the prior art landscape for RE48088 before analyzing obviousness.

Let me pull the actual prior art cited in the Patroll contest and the family IPR, plus the claim text.

Let me identify the specific prior-art references and pull the claim text.

Obviousness Analysis — U.S. Patent No. RE48088 E1 (35 U.S.C. § 103)

Prepared: 2026-04-26 · Analyst task: identify § 103 combinations and motivations to combine

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0. Scope, sources, and a correction to the earlier sections

Sources used here. (a) The Google Patents full text of RE48088 supplied with this matter; (b) the Unified Patents "Patroll" contest record for US‑RE48088‑E1 and Unified's winner announcement; (c) the PTAB petition excerpt (petition 1553926) and the Flexiworld‑family IPR record; (d) the full specification and claims of U.S. 5,884,272 as published by USPTO/Espacenet/uspto.report/lexdana; (e) the "Similar Documents" list generated for RE48088 on the Unified Patents portal; (f) the CBM2014‑00003 record for U.S. 5,884,272.

A correction to the previously generated "Patent summary." That section flagged as unverified whether the PTAB claim listing ("Claims 1, 2, 4, 5, 7, 9, 11 … 52, 57, and 61 … obvious over Keeney") belonged to RE48088 or a sibling. The retrieved petition excerpt resolves this: that listing belongs to U.S. Pat. 9,965,233 (the "'233 patent"), asserted in Flexiworld v. Lexmark, No. 5:22‑cv‑00110 (E.D. Ky.) — Keeney = U.S. 6,748,471 (Ex. 1004), Vatland = Ex. 1005 (patent number truncated in the retrieved text). It is not a claim listing for RE48088, and Keeney/Vatland are not part of the RE48088 prosecution record. I do not rely on them below except as noted in § 8.

Standing caveat (unchanged from the earlier sections): I could not retrieve RE48088's literal claim language this session. The element mapping below is reconstructed from (i) the RE48088 abstract — whose second half ("Client … for accessing an Internet‑based service that data mines user information…") recites the client‑side claim set in near-claim form — (ii) the RE48088 specification, and (iii) Unified's own characterization of the patented subject matter: "a device that, by executing software, can opt into suggestions for connecting with another party. These suggestions are made by a controller unit matching the first party's data with the second party's specifications." Everything below should be re-verified against the issued claim text (USPTO Patent Center, application 15/839,718).

Law applied. Pre‑AIA § 103(a), because the effective filing date predates 2013‑03‑16. Graham v. John Deere, 383 U.S. 1 (1966); KSR Int'l v. Teleflex, 550 U.S. 398 (2007).

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1. The invention, reduced to claim elements

Collapsing the independent claims into elements (E1–E8 controller side; C1–C5 client side):

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2. Person of ordinary skill in the art (POSITA)

A POSITA as of September 2000 would hold a bachelor's degree in CS/EE (or equivalent) plus 2–3 years' experience in network‑mediated communications and web‑based application design, and would be familiar with: PSTN/Internet call‑bridging and telephony gateways; database search and matching algorithms; early collaborative‑filtering/recommendation systems; and client/server and thin‑client (browser/applet/plug‑in) architectures. This is the level at which all of the references below operate.

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3. Prior‑art reference table

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4. Element‑by‑element mapping to the strongest primary reference (Walker‑'272)

Result: Walker‑'272 alone is a very strong § 103 (and arguably § 102) reference against the anonymous‑connection claim family (E1, E4–E8, C1, C2, C5). Its coverage of E2/E3 (data mining → proposed transaction) and C3/C4 (recommendation, advertisement, image/video reference codes) is thinner.

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5. Grounds of rejection

Ground 1 — Walker‑'272 (primary) + Solomon/Telephone Connection + '677

Covers: the anonymous‑connection family (E1, E4–E8; C1, C2, C5).

• Rationale: Solomon patents are the canonical teaching of the exact "code → look up real address → bridge the call → keep the number secret" mechanism. Walker‑'272 supplies the network‑based matching/controller architecture; Solomon supplies the reference‑code/address‑recovery/bridging mechanism and the "system calls the non‑calling party" variant. Both are in telephony‑plus‑data services, the same field, and Solomon is expressly cited on the face of Walker‑'272, so the combination is not hindsight — the artisan was already reading them together.
• KSR fit: "combination of familiar elements according to known methods … yields predictable results"; "a known technique … improv[es] similar devices in the same way." No change in principle of operation: both are held‑call/bridge architectures.

Ground 2 — Walker‑'272 + '406 (matching/scheduling/notification) + applicant's own admitted prior art

Covers: appointment scheduling, mutual connection criteria, "office hours," and post‑connection reuse of a record.

• RE48088's own Background admits as known: user codes tied to stored telephone numbers; contact codes comprising "a call code and password"; parties dialing in at a scheduled time, entering their codes, and being connected if the codes are "proper"; and a record created after the first successful connection so that the system can later call the non‑calling party. Under In re Font / Constant v. Advanced Micro‑Devices and KSR's "any need or problem known in the field," these are admitted prior art and can be used directly in a § 103 combination. The references are "prior art" against RE48088 by the applicant's own description.
• '406 supplies automated matching + scheduling + notification, the piece the RE48088 specification identifies as the unmet need (experts "are not restricted to their office hours"; users need not "wait for their office hours"). The motivation is literally recited in the patent's own "Summary of the Invention."
• Result: scheduling/appointment‑time and reminder limitations are obvious over the admitted art alone or with '406.

Ground 3 — Walker‑'272 or Keen.com‑'165 (primary) for the expert‑marketplace family

Covers: the "information marketplace," expert selection, fee/rate differentiation, and per‑transaction reference codes.

• Keen.com‑'165 ("connect consumer to expert") and Walker‑'223 (expert‑based commerce network) are squarely in the claimed field. If '165's filing date predates 2000‑09‑05, it is § 102(e) art and is the best single‑reference candidate for the controller‑side claims.
• Motivation: same field, same problem (how to find and reach the right expert), same customer; combining the expert‑marketplace matching of '165/'223 with the anonymity/authorization controls of '272 is a predictable union of two known solutions, each performing its own known function.

Ground 4 — Ground 1/2/3 plus the data‑mining/recommendation/advertising cluster (Mantria‑'668; Amazon‑'722; '811; '827; '986; '604) and collaborative‑filtering NPL

Covers: E2, E3, C1, C3, and the "reference code may be image/video/advertisement" sub‑limitations.

• Mantria‑'668 supplies the dynamic data mining + customized online communication step verbatim in substance.
• Amazon‑'722 supplies the legally decisive step: generating a recommendation from the user's own stored transaction history — precisely "data mining the user's history of transactions" to produce a "proposed transaction."
• '811 supplies the advertisement limb of C4; '604 supplies the visual/image identifier limb.
• Motivation / KSR: (i) By 1998, recommender systems were ubiquitous and their combination with e‑commerce was a recognized design trend (KSR's "market demand" and "obvious to try" rationales); (ii) both the recommendation art and Walker‑'272 operate on the same substrate — stored user profile + transaction history in a central database — so combining them requires no architectural change; (iii) the predictable result is a better‑matched suggestion, which is exactly what C2/C3 claim; (iv) the identity‑protection layer of '272 adds privacy to the recommendation, addressing the very "reluctance to disclose" problem RE48088's Background recites. The patent itself frames the invention as this combination, which is strong evidence of the artisan's motivation.

Ground 5 — Design‑choice grounds

• "Application/device/station" claim format (C1): a POSITA implementing the '272 system on a smart phone or browser client would write client software — routine design choice, no patentable weight (see KSR).
• "Defined relationship between reference code and address": met by any stored lookup table or pseudonym mapping ('272), hash, or indexed record. The specification's breadth ("letters, numbers, symbols, graphics, images, video, voice patterns") confirms the mapping is conventional.
• "Defined relationship" vs. encryption: if Patent Owner argues the code must be non‑derivable, note that the reference‑code database/index of RE48088 (column describing reference code database 100) is itself a lookup table — the same structure as '272's pseudonym store.

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6. Why the POSITA would have combined these references (rationales, assembled)

1. Same field of endeavor / same problem. Every reference addresses network‑mediated matching of one party to another and protecting one party's contact information; RE48088's Background expressly surveys the same references and the same unmet needs.
2. Express citation in the primary reference. Solomon/'152 and '890, Clark‑'897, and Shapira‑'394 appear on the face of Walker‑'272 — so the artisan reading '272 was already directed to the anonymous‑connection and personnel‑matching arts. This defeats hindsight.
3. Express statement of the problem in RE48088 itself. The patent identifies (a) reluctance to disclose phone numbers, (b) office‑hour rigidity, (c) inability of a single "user code" to differentiate transactions. Each mapped reference solves one of these — a textbook "known problem provides the reason to combine" rationale (KSR, 550 U.S. at 420).
4. Functional complementarity, no change in principle of operation. Recommendation engine → matching; authorization profile → opt‑in/opt‑out; pseudonym table → reference code; telephone bridge → anonymous channel. Each element performs in the combination exactly the function it performed alone.
5. Reasonable expectation of success. All components existed and were individually deployed (Amazon recommendations; Walker's anonymous channel; The Telephone Connection's bridging); the combination required only ordinary programming.
6. Market demand / industry trend. Monetizing suggestions via advertisements ('811) was a recognized 1990s trend; a POSITA would have seen a competitive need to add targeting and privacy to a matchmaking service.

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7. Anticipated Patent Owner rebuttals, and responses

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8. Priority / § 102 date traps that materially affect the § 103 picture

This is the single most important strategic point and it is not captured in the earlier sections.

• RE48088's asserted priority is 2000‑09‑05 (Prov. 60/230,021); the non‑provisional (09/947,116) was filed 2001‑09‑04 and issued as 7,099,304 on 2006‑08‑29.
• Therefore any claim not supported by the 2000‑09‑05 provisional gets a 2001‑09‑04 effective date, making references filed between those dates § 102(e) prior art:
  • Keeney, U.S. 6,748,471 — filed 2000‑10‑16.
  • Acharya, U.S. Pub. 2002/0080091 — filed 2000‑12‑22 (per the Flexiworld‑family IPR record, where the Board found Flexiworld proved an October 22, 2000 conception date for the '257 patent using provisional‑draft metadata and diligence).
• The client/data‑mining/advertising claim family was added in the reissue chain (RE43,181 → RE46,637 → RE48,088), i.e., after 2008. Those claims face two independent validity risks:
  1. § 112/priority — if the data‑mining‑to‑suggestion subject matter is not supported by the Sept‑2000 provisional, the claims' effective date slips to Sept 2001, and Keeney/Acharya/other 2000–2001 art becomes available.
  2. § 251 (same‑invention / recapture / no broadening after two years) — the original patent issued 2006‑08‑29; broadened reissue is time‑barred, so the reissue claims must be for the same invention. Claims directed to an advertising‑funded, data‑mined, opt‑in suggestion service are arguably a different invention. This is a validity challenge in its own right, and it feeds directly into § 103 by moving the critical date.
• Notably, Flexiworld prevailed on this precise priority fight in IPR2022‑00775 (Unified v. Flexiworld, Paper 41, Nov. 1, 2023) for the '257 patent, using provisional‑draft metadata as corroboration of an Oct. 22, 2000 conception. Expect Flexiworld to attempt the same "swear‑behind" maneuver for RE48088. The counter is that the '257 patent record establishes conception only for claims 27–28 of the '257 patent, not for the RE48088 reissue claims, and that adding a new data‑mining claim in reissue cannot retroactively capture a 2000 conception date it does not describe.

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9. Overlap with the § 101 disposition (context, not § 103)

Per the earlier litigation summary, Judge Albright dismissed the Flexiworld v. Indeed case with prejudice on § 101 grounds before claim construction (characterization sourced from Indeed's counsel's public bio — order text not retrieved). Two practical consequences for a § 103 analysis:

• If the § 101 dismissal holds on appeal, the § 103 analysis is largely moot for the Indeed matter, but still relevant to any patent‑office proceeding, any past‑damages window (the patent is listed Expired – Lifetime, adjusted expiration 2024‑04‑30), and any other assertion.
• The § 101 outcome does not mean the claims were found valid over prior art. A § 103 challenge remains the more durable invalidity theory across the whole family, and the overlap is significant: the abstract‑idea core (matching a person to another and brokering a connection) is exactly what Walker‑'272 discloses as a concrete, claimed 1996 system.

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10. Confidence and verification status

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11. Citations (URLs used)

• RE48088 full text — https://patents.google.com/patent/USRE48088E1/en
• Unified Patents portal page / Google "similar documents" for RE48088 — https://portal.unifiedpatents.com/patents/patent/RE48088
• Unified Patents Patroll contest for US‑RE48088‑E1 (target: at least claim 52; claimed U.S. 5,884,272, U.S. 7,957,991, U.S. 2003/0158960, U.S. 5,862,223) — https://patroll.unifiedpatents.com/contests/5M4duRZBqwxMYnFDP
• Unified winner announcement (2025‑03‑29) — https://www.unifiedpatents.com/insights/2025/3/29/1500-awarded-for-flexiworld-technologies-communication-patents-prior-art
• PTAB petition 1553926 (Keeney/Vatland; the '233 patent, Lexmark) — https://ptacts.uspto.gov/ptacts/public-informations/petitions/1553926/download-documents
• Flexiworld family IPR priority/conception decision (IPR2022‑00775) — https://www.jdsupra.com/post/contentViewerEmbed.aspx?fid=2776ab14-e0c5-4e83-b8b1-99c5b2aa16ae
• U.S. 5,884,272 full text/claims — https://uspto.report/patent/grant/5884272 ; https://insight.rpxcorp.com/patent/[US5884272A](/patent/US5884272A)
• CBM2014‑00003 (U.S. 5,884,272; Silvermann, Rogaway, Clark, Shapira grounds) — https://ai-lab.exparte.com/case/ptab/CBM2014-00003/doc/summary/3

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12. Bottom line

Strong § 103 case, built on a small number of well‑dated, in‑field references.

1. Walker‑'272 is dispositive primary art for the anonymous‑connection claims — a central controller that matches a seeker to another party from stored profile data, issues a pseudonym/coded identifier tied to that party's address, receives a channel request bearing the pseudonym, and opens a telephone (real‑time) or e‑mail (non‑real‑time) channel without revealing identity, with billing and express applications to job search, dating, and consulting/freelance engagements. It was independently identified by Unified Patents as winning prior art against RE48088.
2. Solomon/The Telephone Connection ('152/'890/'295) and '677 supply the reference‑code→address‑recovery→bridging mechanism with precision.
3. The data‑mining/proposal/advertisement/client claims fall to Mantria‑'668 + Amazon‑'722 + '811 (+ '827/'986/'604) in view of '272/'165/'223, with collaborative‑filtering NPL as background. The motivation is expressly supplied by RE48088's own statement of the problem.
4. The scheduling/appointment claims fall to Walker‑'272 + '406 and to the applicant's own admitted prior art (user codes, contact codes with passwords, scheduled dial‑in and code comparison, record‑based callback) recited in the patent's Background.
5. The most under‑appreciated lever is the priority date. If the reissue's data‑mining/client claims are not entitled to the 2000‑09‑05 provisional, references filed October–December 2000 (Keeney, Acharya) become § 102(e) art, dramatically widening the § 103 attack — and the § 251 "same invention" constraint on reissue claims supplies an independent basis to test that priority.

Recommended next step before finalizing any chart: pull the literal claim text and independent‑claim numbering from USPTO Patent Center for application 15/839,718, and confirm the filing dates of U.S. 6,223,165, U.S. 7,957,991, and U.S. 2003/0158960, none of which I could verify in this session.