US 7163283

I'll verify against live sources before summarizing.

US Patent 7,163,283 — Verified Summary

Source check: Confirmed against Google Patents (https://patents.google.com/patent/[US7163283](/patent/US7163283)/en, fetched 2026-09-28). I found no active or historical litigation, ITC action, or CAFC/Court of Federal Circuit docket referencing U.S. 7,163,283 in my searches. My searches for CAFC 2026 dockets returned only unrelated matters (e.g., Slingshot Printing LLC v. Canon U.S.A., Fed. Cir. Nos. 25-1032/25-1033). I do not have authoritative docket information for this patent, and I am not asserting that none exists — only that I could not find any. One caution: the string "7163283" also matches Japanese patent JP 7163283 B2 (Techno UMG K.K., thermoplastic resin composition, registered 2022), an entirely unrelated document. Do not conflate them.

Bibliographic Data

Abstract (as issued)

A system to recycle waste ink for reuse as replenishment fluid, for an inkjet print station including a printhead with a fluid inlet and a fluid outlet. The system uses an ink supply tank, an external ink supply tank with fresh ink, and an ink supply valve controlling ink flow from the external tank to the ink supply tank. It includes a replenishment fluid supply valve controlling flow between a replenishment fluid supply and the ink supply tank, a device for monitoring ink concentration in communication with ink, a waste tank, and a waste reuse valve controlling flow between the waste tank and the ink supply tank. The system includes level sensors and one or more controllers to control valves, sensors, and pumps to optimize operation.

Core disclosure

The patent addresses solvent-based continuous inkjet printing, where solvent is drawn from a replenishment container both to replace vehicle lost to evaporation and to flush the printhead during startup, shutdown, and cleaning. In the prior art that flush fluid went to a waste tank and was manually drummed as hazardous waste. The invention instead routes that waste fluid back into the ink supply tank under closed-loop concentration control, with three possible make-up sources: fresh ink, reclaimed waste fluid, or virgin replenishment fluid. The specification claims the recycle system reduces operating cost "by more than 30%" versus a comparable printer without it, and cites U.S. Pat. No. 5,526,026 (incorporated by reference) for resistivity-based concentration control (ink resistivity expected ~430 ohm-cm). Representative hardware: printhead 10, ink supply tank 16 (1–6 L), external ink supply tank 17 (1–1000 L), replenishment fluid supply 22 (~20 L, e.g. MEK, <2% colorant), waste tank 30 (0.5–5 L), concentration device 38 (optical, viscosity, resistivity, or drop-count), waste reuse valve 40, and controller 42. A gravity-fed, pump-less version is described as preferred.

Independent Claims in Plain Language

Claim 1 — the system. An inkjet print station waste-recycling system comprising:

• (a) a printhead having a fluid inlet and a fluid outlet;
• (b) an ink supply tank holding ink and including a first level sensor, plumbed to the printhead inlet;
• (c) a replenishment fluid supply plumbed to the printhead inlet;
• (d) a replenishment fluid supply valve controlling flow between that supply and the ink supply tank;
• (e) a waste tank holding waste fluid, plumbed to both the ink supply tank and the printhead outlet;
• (f) a device for monitoring ink concentration, in communication with the ink;
• (g) a waste reuse valve controlling flow between the waste tank and the ink supply tank; and
• (h) at least one controller that optimally controls the valve, the first level sensor, and the monitoring device, comparing measured ink concentration against preset levels to control ink flow.

In substance: a closed recycle loop in which used flush fluid is held in a waste tank and selectively returned to the ink supply tank, with the return decision driven by a concentration sensor rather than by disposal.

Claim 19 — the method. A method of recycling waste for use as replenishment in an inkjet print station, comprising:

1. flushing ink residues from the printhead with replenishment fluid from a replenishment fluid supply tank, thereby forming waste fluid;
2. flowing that waste fluid into a waste tank;
3. sensing ink level in the ink supply tank with a first level sensor;
4. measuring ink concentration with a monitoring device to determine one of four outcomes:
   • (i) concentration below a first preset → fresh ink flows from the external ink supply tank into the ink supply tank;
   • (ii) concentration above the first preset but below a second preset → waste fluid flows from the waste tank into the ink supply tank;
   • (iii) concentration above the second preset → replenishment fluid is added from the replenishment fluid supply tank; and
   • (iv) the waste tank is empty → replenishment fluid is added from the replenishment fluid supply tank.

The specification supplies working values for the presets: first preset = 100% of normal concentration, second preset = 130% of normal ink concentration. That is the heart of the "concentration control" in the title — reclaimed waste fluid is used as the make-up stream only within a controlled concentration band, otherwise virgin solvent or fresh ink is used.

Points of Uncertainty / Caveats

• No corroborated litigation or CAFC 2026 docket information exists in what I retrieved for this number. Treat any assertion of enforcement activity as unverified.
• Claim drafting artifacts are reproduced literally above. In claim 1 element (h), "the controller" appears where the element was introduced as "at least one device"; in claim 19 the preamble reads "for use as a replenishment for"; and sub-paragraph (i) refers to "the first preset concentration value" without an antecedent "a" in that branch. These are as-issued readings, not my corrections.
• Cited prior art of record (8 references): US 3,835,881; US 4,067,020; US 4,337,468; US 4,825,228; US 5,418,557; US 5,473,350; US 5,526,026; and US 5,930,555. Note the clustered lineage from A.B. Dick, Ricoh, Videojet, and Scitex Digital Printing — the same technical field, suggesting a well-developed art.
• Forward citations of note: US 8,991,986 B2 (Eastman Kodak, "Continuous inkjet printing method," filed 2012-04-18) and the Plastipak Packaging family US 8,231,212 / 8,360,566 / 8,864,295 / 8,888,210 (ink delivery systems / methods for printing).
• The security-interest assignments recorded between 2012 and 2020 (Citicorp, Wilmington Trust, JPMorgan Chase, Barclays, Bank of America, and releases thereof) reflect Kodak's financing arrangements, not transfers of title.

I'll research litigation involving US patent 7163283.

The first search surfaced a "'328 Patent" in Facet Tech. Corp. v. Mobileye — but that may be a different patent. Let me verify and search more precisely.

Confirmed the Facet/Mobileye "'328" is U.S. 9,671,328 — a different patent, not relevant. Let me search databases directly for 7,163,283.

Answer: No litigation involving U.S. Patent No. 7,163,283 was found.

Bottom line

Based on my searches, I found no known litigation (district court, ITC, CAFC appeal, or PTAB proceeding) asserting or challenging U.S. Patent No. 7,163,283. I cannot report a plaintiff, defendant, jurisdiction, case number, filing date, or outcome, because no case tied to this specific patent number surfaced.

What I verified about the patent itself

• Patent: U.S. 7,163,283 B2 — "Reuse of solvent startup/shutdown fluid for concentration control"
• Application: US 10/970,105; filed 2004-10-21; granted/publication 2007-01-16 (pre-grant pub. US 2006/0087539 A1)
• Inventor(s): John C. Loyd; James D. McCann
• Original/current assignee: Eastman Kodak Company
• Statutory disclaimer / no patent-term extension events apparent, and its legal status is "Expired – Fee Related" — the record shows a lapse for failure to pay maintenance fees (event dated 2019-02-18, effective 2019-01-16), with an adjusted expiration of 2025-04-08.
• It has a small forward-citation family (e.g., Plastipak Packaging's ink delivery/method-for-printing filings; Eastman Kodak's own US 8,991,986), but citations are not litigation.

Important caution — do NOT confuse this with look-alike numbers

My searches kept surfacing different patents whose numbers end in "…328" or share digits. None of these is U.S. 7,163,283, and I am flagging them explicitly so they are not misattributed:

1. Facet Technology Corp. v. Mobileye Global, Inc., No. 2:24-cv-00058-RWS-RSP (E.D. Tex., filed Jan. 26, 2024) — asserts U.S. Patent No. 9,671,328 ("'328 Patent" in that case, a road-marker/ADAS patent), plus U.S. 9,335,255. Related PTAB matters include IPR2024-01110 (on the '255 patent). Not U.S. 7,163,283.
2. Broadcom Corp. / Avago Technologies v. Netflix — involves U.S. Patent No. 9,322,283. Not relevant.
3. Nissan Motor Co. v. Longhorn Automotive (IPR2025-01089) — involves U.S. Patent No. 7,513,238. Not relevant.
4. JP 7163283 B2 — a Japanese patent (Techno UMG K.K.) directed to a "thermal plastic resin composition." Same digits, entirely different jurisdiction and subject matter. Not relevant.

Caveats and confidence

• The strongest, fully verified source here is the patent's own prosecution/assignment/legal-status record (Google Patents page for US 7,163,283), which shows fee-lapse and no litigation entries.
• Confidence that no litigation exists: moderate-to-high, not absolute. My attempts to run direct docket-level queries against the specific databases you named — Unified Patents' litigation portal (portal.unifiedpatents.com/litigation/caselist), RPX Empower, Docket Alarm, and PACER/CAFC — did not complete before I hit my tool-step limit. It is possible a short-lived or settled suit exists that only appears in those full-text docket systems and did not surface in keyword search.
• Recommended confirmatory steps if you need a definitive litigation clear under the strict no-auto-correct rule:
  1. Query PACER / Docket Alarm by exact patent number 7,163,283 (and separately by 7163283).
  2. Search the Unified Patents litigation caselist and RPX Empower filtered to patent number 7163283.
  3. Check PTAB (IPR/PGR/CBM) for any petition naming 7,163,283 as the challenged patent.
  4. Given the patent lapsed in 2019 for non-payment of maintenance fees, the practical likelihood of active or recent assertion is low.

Result: No litigation known for U.S. Patent 7,163,283. If you want, I can retry the docket-database-specific queries (Unified Patents, RPX, PACER) in a follow-up to convert that "no known litigation" into a fully cleared negative.

I'll verify the ODP's "no proceedings" baseline against public sources before writing this up.

The ODP returned no proceedings, but one search hit shows a PTAB petition involving a "'328 Patent" in Facet Tech v. Mobileye. I need to confirm whether that is US 7,163,283 or a different patent.

Confirmed the Facet/Mobileye "'328" is US 9,671,328 — an unrelated patent. Now let me verify no AIA trial or other post-issuance proceeding attaches to US 7,163,283 itself.

Proceedings overview

Zero AIA trial proceedings — no IPR, PGR, or CBM — have ever been filed against US 7,163,283, and the patent is no longer enforceable for a more fundamental reason: it lapsed for failure to pay maintenance fees, with the lapse event effective 2019-01-16, and its nominal adjusted term (2025-04-08) has now run out as well. Breakdown by status is therefore 0 active / 0 claims invalidated / 0 claims sustained / 0 settled / 0 institution denials. Defensive posture: there is no IPR record to attack or defend, but you do not need one — any demand letter asserting a claim of 7,163,283 in 2026 is asserting an expired patent, which is the single most useful fact in this file.

Proceedings on file

There are no AIA trial proceedings to profile. Per the structured "PTAB proceedings on file" block sourced from the USPTO Open Data Portal, the ODP returns no AIA trial proceedings for US 7,163,283 as of the most recent ingest, and independent web searching on 2026-09-28 corroborated that: no IPR/PGR/CBM petition, no institution decision, no Final Written Decision, no termination, and no Federal Circuit appeal naming this patent surfaced.

Because there is no FWD, the per-proceeding template (petitioner, panel, grounds, institution reasoning, claim-level verdict, settlement, appeal) has no content to populate. I am not going to fill those fields with inferences — that would be fabrication.

Verification trail (what I actually checked)

• ODP structured block (canonical): no AIA trial proceedings on file. This is the authoritative list and I did not override it.
• Web search for adversarial proceedings: queries targeting the patent number, the title ("Reuse of solvent startup/shutdown fluid for concentration control"), and Kodak-as-patent-owner returned no petition, decision, or docket entry for this patent. The only hits tied to "7,163,283" were unrelated (a Peruvian health-services resolution, a Japanese Patent No. 7163283 for a thermoplastic resin composition, a San Diego environmental-inspection sequence ID, and a Delhi University exam roll number) — none of them this patent.
• No Federal Circuit activity: no CAFC opinion or docket entry naming US 7,163,283. CourtListener's database is searchable at https://www.courtlistener.com/ and returned nothing for this patent.
• Consistency check on the record itself: the full granted text at https://patents.google.com/patent/US7163283/en shows a clean prosecution-to-grant history (filed and priority-dated 2004-10-21; granted 2007-01-16; a certificate of correction 2008-05-06; 4-year fee paid 2010-06-22; 8-year fee paid 2014-06-24) with no third-party post-grant contest.

False-positive flag — do NOT confuse this patent with US 9,671,328

This is worth stating explicitly, because searching "328 patent" plus PTAB returns a busy, substantively rich record that belongs to a different patent:

• IPR2024-01110 and IPR2024-01111, Mobileye Global Inc. v. Facet Technology Corp., involve US 9,671,328 ("System and assessment of reflective objects along a roadway" — road-marker retroreflectivity, inventors Retterath and Laumeyer, asserted in Facet Tech. Corp. v. Mobileye Glob., Inc., No. 2:24-cv-00058 (E.D. Tex.) and in Facet Tech. Corp. v. General Motors LLC, No. 2:24-cv-00035 (E.D. Tex.)).
• The Facet '328 patent was also hit with an ex parte reexamination requested by Unified Patents on 2024-06-20, granted by the CRU on 2024-07-15 (reexam control 90/019,546).

None of that touches US 7,163,283 — the claim sets, specifications, owners, and technology (inkjet waste-fluid recycling vs. roadway reflectivity classification) are entirely different. If a search tool or an adversary's chart conflates the two, correct the record immediately.

Strategic summary

Claim status on 7,163,283. All claims 1–25 are UNTESTED — no claim was ever canceled, narrowed, or sustained in any AIA trial, and no certificate of correction or reexamination (that I could find) altered claim scope. Claims 1–18 are system claims (claim 1 independent; claim 19 independent method claim with claims 20–25 depending from it). The absence of any PTAB narrowing cuts against a defendant who hoped to point at a canceled claim, but it does not matter here, because the enforceability question dominates.

Enforceability is the whole ballgame. The public legal-events record shows a maintenance-fee reminder mailed 2018-09-03, a "Lapse for failure to pay maintenance fees" event dated 2019-02-18 with an effective lapse date of 2019-01-16, and "PATENT EXPIRED DUE TO NONPAYMENT OF MAINTENANCE FEES UNDER 37 CFR 1.362." No petition to revive or reinstatement appears in the events list. Google Patents carries the status "Expired – Fee Related" with a nominal adjusted expiration of 2025-04-08 (filed 2004-10-21 plus PTA); as of today, 2026-09-28, that date has passed too. Two independent conclusions follow: (i) the patent's statutory term is over, and (ii) even before that, rights were cut off in January 2019.

Estoppel landscape — n/a, and that's the point. Because no IPR reached a Final Written Decision, there is no § 315(e)(2) estoppel against anyone. Every ground is available to a hypothetical defendant: § 102/§ 103 over the eight references of record (US 3,835,881; 4,067,020; 4,337,468; 4,825,228; 5,418,557; 5,473,350; 5,526,026; 5,930,555), plus § 112 and § 101 theories, plus the on-sale/§ 102(b) body of Kodak Versamark DS 7122 and DS 4300 product art that the specification itself describes as prior practice. The more practical point is that invalidity is largely academic: with the patent lapsing 2019-01-16, the § 286 six-year damages lookback from any complaint filed today reaches back only to approximately 2020-09-28 — a window in which the patent was never in force.

Pattern signals. No petitioner ever filed against this patent, so there is no repeat-petitioner pattern, no joinder, and no defensive aggregator (Unified Patents or similar) in the chain for this patent — the Unified/re-exam activity surfaced in search belongs to Facet's US 9,671,328, not here. The patent owner (Eastman Kodak) never had occasion to defend it at the PTAB and never appealed anything to the Federal Circuit concerning it. The Kodak assignment trail from 2012 onward is security-interest churn (Citicorp, Wilmington Trust, JPMorgan, Barclays, Bank of America) with releases — collateral housekeeping, not evidence of assertion activity.

Recommended next steps

1. Lead with expiry, not invalidity. If your client is receiving demand letters citing US 7,163,283, the first response is that the patent lapsed for nonpayment of the 12-year maintenance fee effective 2019-01-16 (37 C.F.R. § 1.362) and its nominal adjusted term expired 2025-04-08. Link the Google Patents legal-events timeline: https://patents.google.com/patent/US7163283/en (see "Lapse for failure to pay maintenance fees," 2019-02-18, effective 2019-01-16).
2. Verify on the authoritative USPTO systems before relying on it. Pull the Patent Center maintenance-fee tab and the fee/status history via https://patentcenter.uspto.gov/ and confirm (a) no 12-year fee was ever paid, and (b) no petition to revive under 37 C.F.R. § 1.378 was granted. My conclusion rests on the public events list; I did not see a revival event, but a revival would change the analysis with respect to any pre-lapse conduct.
3. Check the CRU separately for ex parte reexamination. The ODP block covers AIA trials only. I found no reexamination certificate for this patent, but if you want belt-and-suspenders, query the reexamination control-number database and the Patent Center file wrapper for this patent's application number, 10/970,105.
4. If anyone claims a PTAB win on this patent, get the patent number in writing. The live PTAB record for a "'328 patent" is Mobileye v. Facet (US 9,671,328), where statutory disclaimers, not just Board rulings, knocked out claims 17–22; that case has nothing to do with Kodak's '283. See USPTO PTAB E2E for docket verification: https://ptacts.uspto.gov/ptacts/.
5. For prior-art/estoppel purposes: since no IPR exists, there is no estoppel to work around and no need to plan around petitioner/privy bars. If a case ever matters, start from the eight references cited on the face of the patent — particularly US 5,526,026 (Scitex, resistivity-based concentration control, expressly incorporated by reference for the 430 ohm-cm point) and US 5,473,350 (Scitex, maintaining ink concentration) — and from the admitted prior-art practice described in the specification at the "Background of the Invention" section.

Bottom line for a defendant today: there is no PTAB activity on file for US 7,163,283, and more importantly there is no remaining patent term to litigate. The absence of IPRs is not because the patent was a hardened survivor of adversarial challenge — it is because the patent lapsed in 2019 and the 20-year term ended in 2025, so nobody ever had a reason to file.

I'll verify what I can from the record and check for any litigation or NPE activity tied to this patent.

Ownership & Assignment Reconstruction — US 7,163,283 B2

Patent: US 7,163,283 B2 ("Reuse of solvent startup/shutdown fluid for concentration control")
Application: US 10/970,105 · filed & priority 2004-10-21 · granted 2007-01-16 · pub. US 2006/0087539 A1 (2006-04-27)
Assignee of record (Google Patents legal events): Eastman Kodak Company

Sourcing caveat up front. The authoritative text supplied for this patent reproduces the Google Patents legal events view of the assignment record, which contains reel/frame, conveyance type, assignor, assignee, and execution/recording dates — but not the Assignment Center "correspondent of record" (recording attorney/agent) field. I could not retrieve that field from the live Assignment Center (it is a JavaScript search app; the searches I ran returned no assignment-level correspondent data). I therefore report correspondents as not determinable from the available record rather than inferring them. That is one of the requested data elements and it is a genuine gap, not an omission.

Inventors

Basis and notes.

• The patent names two inventors, Loyd and McCann, and the assignment recorded at reel 015917/0035 identifies them as the sole assignors to Eastman Kodak Company.
• Employer inference: the specification is written around Kodak's own commercial hardware — "print station number DS 7122 offered by Kodak Versamark™ of Dayton, Ohio," the "Model DS 4300," and Kodak Versamark inks FD 7101 and FD 7102. Kodak completed its $250M acquisition of Scitex Digital Printing (Dayton/Kettering, OH) in January 2004 and renamed it Kodak Versamark, Inc., a wholly-owned subsidiary (Dayton Business Journal, 2004-01-26; PIWorld; WhatTheyThink press release 2004-02-26). The application was filed 2004-10-21, i.e. ~9 months after the acquisition, so the inventors were resolving as Kodak Versamark personnel. Both inventors are indexed as Eastman Kodak inventors with other filings (PatentLeaderboard profiles: Loyd ~12 patents, McCann ~15).
• Unusual-pattern check: Not present. The assignment was executed 2004-08-23 and recorded 2004-10-21, i.e. a routine pre-filing assignment from employee-inventors to the corporate parent. There is no evidence of inventors departing the assignee within 12 months of filing, and none is determinable from the assignment record alone.

Original assignee

Eastman Kodak Company, Rochester, New York (assignee/owner name of record: "EASTMAN KODAK COMPANY, NEW YORK," reel 015917/0035).

• Primary line of business: imaging and commercial printing. At filing, this patent sat inside Kodak's then-new Commercial Printing Group / Enterprise Inkjet Systems segment built on the Versamark continuous-inkjet platform.
• Did they ship a product embodying the claims? Yes, on the face of the record. The specification itself is anchored to shipped Kodak Versamark products and consumables (DS 7122 print station spec: 200 ml/min, 240 jets at 120 jets/inch, 7½ psi; FD 7101 ink; FD 7102 replenishment ink), and Kodak marketed the Versamark V-Series. The patented subject matter — reusing startup/shutdown/cleaning flush fluid as make-up for evaporative losses — is a cost-of-ownership feature of that consumables business. This is a consumables/infrastructure patent, not a standards or licensing-only asset.
• Current status: Operating, but with a material history. Eastman Kodak filed Chapter 11 on 2012-01-19 (Bankr. S.D.N.Y., No. 12-10202), sold ~1,100 digital imaging patents to an Intellectual Ventures/RPX-led consortium for $527M (final $525M, approved Dec. 2012), and emerged in September 2013. The corporate parent remains publicly traded (KODK). Kodak's later 10-K describes "the PROSPER Enterprise Inkjet business" among discontinued operations — relevant context for why a 2004 inkjet-process patent was allowed to lapse rather than be monetized.
• Legal status of the patent: Expired — fee related. Recorded events show a maintenance-fee reminder (2018-09-03), notice of lapse for failure to pay (2019-02-18), and "patent expired due to nonpayment of maintenance fees" (2019-03-12, effective 2019-01-16). Note the internal inconsistency in the source: the Google Patents banner also carries "Expired - Fee Related, expires 2025-04-08" and a 2025-04-08 "adjusted expiration" entry. Read literally, 2025-04-08 is the nominal end of the adjusted term (20 years from the 2004-10-21 filing plus adjustment), not the effective date of expiration. Per the recorded events, the patent went abandoned in 2019-01-16, and no reinstatement/petition event appears in the fetched record.

Assignment timeline

Every recorded event affecting the chain, chronological. Note that only the first event conveys ownership; everything after 2012 is a security interest or a release of one.

• 2004-10-21 (executed 2004-08-23) / recorded 2004-10-21 — Reel 015917/0035

  • Conveyance: Assignment (Assignment of assignors' interest)
  • Assignor: John C. Loyd; James D. McCann (individually)
  • Assignee: Eastman Kodak Company, Rochester, New York
  • Correspondent: not determinable — the recorded free-format text identifies Kodak as owner but the correspondent/recording-agent field is absent from the source record. No recurrence can be assessed.
  • Context: Initial corporate assignment of employee-inventor rights, executed ~2 months pre-filing — the only true ownership transfer in the chain.

• 2012-02-21 (executed 2012-02-15) / recorded 2012-02-21 — Reel 028201/0420

  • Conveyance: Security Interest
  • Assignor: Eastman Kodak Company; Pakon, Inc.
  • Assignee: Citicorp North America, Inc., as Agent
  • Correspondent: not determinable (field absent).
  • Context: Securitization — debtor-in-possession/senior secured financing granted as Kodak entered Chapter 11 (pledged across a bundle of Kodak and Pakon patents, not this asset alone).

• 2013-04-01 (executed 2013-03-22) / recorded 2013-04-01 — Reel 030122/0235

  • Conveyance: Patent Security Agreement
  • Assignor: Eastman Kodak Company; Pakon, Inc.
  • Assignee: Wilmington Trust, National Association, as Agent
  • Correspondent: not determinable (field absent).
  • Context: Securitization — junior DIP lien on the same collateral pool.

• 2013-09-05 (executed 2013-09-03) / recorded 2013-09-05 — Reel 031157/0451

  • Conveyance: Release of Security Interest in Patents
  • Assignor (releasing parties): Citicorp North America, Inc. (Senior DIP Agent); Wilmington Trust, N.A. (Junior DIP Agent)
  • Assignee: Eastman Kodak Company; Pakon, Inc. (i.e., back to the patent owner)
  • Correspondent: not determinable (field absent).
  • Context: Release upon exit financing — the DIP liens were cleared so the reorganized Kodak could grant first/second-lien and ABL security to the exit lenders.

• 2013-09-05 (executed 2013-09-03) / recorded 2013-09-05 — Reel 031158/0001

  • Conveyance: Intellectual Property Security Agreement (First Lien)
  • Assignor: Eastman Kodak Company; Far East Development Ltd.; FPC Inc.; and others (Kodak group)
  • Assignee: JPMorgan Chase Bank, N.A., as Administrative Agent
  • Correspondent: not determinable (field absent).
  • Context: Securitization — first-lien collateral pledge securing Kodak's 2013 exit financing.

• 2013-09-05 (executed 2013-09-03) / recorded 2013-09-05 — Reel 031159/0001

  • Conveyance: Intellectual Property Security Agreement (Second Lien)
  • Assignor: Eastman Kodak Company; Far East Development Ltd.; FPC Inc.; and others
  • Assignee: Barclays Bank PLC, as Administrative Agent
  • Correspondent: not determinable (field absent).
  • Context: Securitization — second-lien pledge recorded the same day as the first lien.

• 2013-09-05 (executed 2013-09-03) / recorded 2013-09-05 — Reel 031162/0117

  • Conveyance: Intellectual Property Security Agreement (ABL)
  • Assignor: Eastman Kodak Company; Far East Development Ltd.; FPC Inc.; and others
  • Assignee: Bank of America N.A., as Agent
  • Correspondent: not determinable (field absent).
  • Context: Securitization — asset-based-lending collateral pledge; third of the three simultaneously recorded exit-financing liens.

• 2019-07-22 (executed 2019-06-17) / recorded 2019-07-22 — Reel 049814/0001

  • Conveyance: Release by Secured Party
  • Assignor: JPMorgan Chase Bank, N.A., as Administrative Agent
  • Assignee: Eastman Kodak Company and 15 affiliated Kodak entities (Kodak Realty, Pakon, Kodak Portuguesa, Far East Development, Laser Pacific, Kodak Imaging Network, Kodak Philippines, Kodak Americas, NPEC, Qualex, FPC, Kodak Aviation Leasing, Kodak Near East, Creo Manufacturing America)
  • Correspondent: not determinable (field absent). No recurrence assessable — see signal 3 below.
  • Context: Release of the first-lien security interest after the underlying debt was satisfied (~6 years post-emergence).

• 2020-01-24 (executed 2017-02-02) / recorded 2020-01-24 — Reel 052773/0001

  • Conveyance: Release by Secured Party
  • Assignor: Barclays Bank PLC
  • Assignee: Eastman Kodak Company and 11 affiliated Kodak entities
  • Correspondent: not determinable (field absent).
  • Context: Release of the second-lien security interest; note the 3-year gap between the stated effective date (2017-02-02) and the recording date (2020-01-24).

Two record-integrity items worth flagging for verification:

1. No release is recorded for the Bank of America ABL lien at reel 031162/0117 in the fetched legal-events list. Either it was released in an event not surfaced, or the security interest remains of record. Verify in Assignment Center.
2. No assignment of this patent appears in the Kodak Chapter 11 patent sale. The 2012–2013 $527M transaction (IV/RPX-led superconsortium) covered the digital capture (DC) and imaging systems & services (KISS) portfolios; no reel/frame in this patent's chain reflects a transfer to Intellectual Ventures, RPX, or any consortium member.

Timeline diagram

timeline
    title Ownership of US 7163283
    2004 : Inventors assign to Eastman Kodak
         : Application filed
    2007 : Patent issued to Kodak
    2012 : Security interest to Citicorp
    2013 : Wilmington Trust security agreement
         : DIP liens released back to Kodak
         : JPMorgan first lien recorded
         : Barclays second lien recorded
         : Bank of America ABL lien recorded
    2019 : Patent lapses for unpaid fees
         : JPMorgan lien released
    2020 : Barclays lien released

NPE / troll-pattern signals

1. Shell-entity transfer — not present.
No recorded conveyance moves this patent to any entity with an "IP / Patents / Licensing / Holdings / Ventures" suffix, and no assignee of record is a single-purpose LLC. The only assignee of record is Eastman Kodak Company (reel 015917/0035). Every post-2004 recording is a lien or a lien release, not a transfer to a licensing vehicle.

2. Known asserter in the chain — not present.
No assignee or recorded party matches the named NPE list (Acacia, Marathon, Intellectual Ventures, IPNav, Wi-LAN, Mosaid/Conversant, Vringo, Pendrell, Innovatio, MPHJ, Lumen View, Round Rock, Document Generation Corp, Spangenberg entities, or any Unified Patents/RPX high-frequency plaintiff). Searches for this patent number in litigation/PTAB sources returned no assertion activity. The nearest famous facts — IV/RPX involvement in Kodak's 2013 patent sale — are directed at the digital imaging portfolios, and this patent was not in that sale (no recorded transfer; see "Original assignee" above). Being in the same company's portfolio as patents IV bought does not put IV in this chain.

3. Repeat correspondent across the chain — unclear (data unavailable).
The required data element — the recording attorney/agent of record — is not present in the source I was given. The 2004 assignment's recorded text names Eastman Kodak Company as owner, and the 2012–2013 and 2019–2020 recordings name only institutional secured parties and their agents; the correspondent fields are blank. I cannot make this call, and naming an attorney here would be fabrication. If Assignment Center is queried directly, the highest-value check is whether the five 2013-09-03-dated recordings (reels 031157/0451, 031158/0001, 031159/0001, 031162/0117, and 030122/0235) share one lender-counsel firm — that would be an ordinary secured-financing pattern (one firm for the lender group), not an NPE tell.

4. Cascading transfers — not present.
There are no consecutive ownership assignments, let alone chained LLCs. The apparent cluster is five recordings all dated 2013-09-05 but executed 2013-09-03 (reels 031157/0451, 031158/0001, 031159/0001, 031162/0117) plus the earlier 2013-04-01 package. That clustering reflects one simultaneous exit-financing closing (release of DIP liens → grant of first lien, second lien, and ABL) across a large shared collateral pool, not serial transfers. Read literally, the dates are consistent with a single credit event.

5. Pre-litigation transfer — not present.
No infringement suit naming US 7,163,283 was found in any district court, ITC, or PTAB source I searched. With no litigation to precede, the signal cannot arise. Also note the patent lapsed 2019-01-16 for non-payment of maintenance fees before any assertion could be brought, and a lapsed patent cannot support a damages case.

6. Bankruptcy fire-sale — not present for this patent (with an important near-miss).
Eastman Kodak did file Chapter 11 (2012-01-19, S.D.N.Y. No. 12-10202) and did sell ~1,100 digital imaging patents in a court-approved 2013 transaction. That is exactly the "Kodak → IV/RPX" fact pattern this signal is designed to catch — but it did not touch this patent. The only Kodak-related recordings in this chain are security interests and releases; there is no assignment to the consortium, to Intellectual Ventures, or to any bidco. The patent stayed with Kodak, was not scheduled into the sale, and was later allowed to lapse.

7. Privateering — not present.
No operating-company-to-NPE transfer, no alliance between Kodak and an assertion vehicle over this asset, and no SEC/press coverage of any such arrangement involving this patent.

8. Defensive aggregator — not present.
The chain does not terminate at RPX, AST, LOT Network, Unified Patents, or OIN. It terminates at the original operating company. (RPX appears in this story only as a consortium participant in the 2013 Kodak sale, which — again — did not include this patent.) The "neutralized" outcome here came from failure to pay maintenance fees, not from aggregation.

Verdict

Insufficient data.

The assignment record for US 7,163,283 contains exactly one conveyance of ownership — the inventors' pre-filing assignment to Eastman Kodak Company at reel 015917/0035, executed 2004-08-23 and recorded 2004-10-21. Everything recorded thereafter (reels 028201/0420, 030122/0235, 031157/0451, 031158/0001, 031159/0001, 031162/0117, 049814/0001, 052773/0001, 2012-02-15 through 2020-01-24) is a security interest or a release of one, i.e. a securitization and its unwind, not a change in ownership. There is no shell-entity transfer, no known asserter, no cascading LLC chain, no pre-litigation transfer, and no defensive aggregator at the end — the patent simply lapsed 2019-01-16 for non-payment of maintenance fees while still owned by Kodak. The verdict is recorded as Insufficient data because the labeled outcome categories are all framed around assertion or aggregation, and the two clean negative findings here are (a) zero NPE assignment activity and (b) zero litigation; the one requested element I could not observe (recording correspondent) is unavailable rather than adverse.

Verification links:

• USPTO Assignment Center: https://assignmentcenter.uspto.gov/
• Legacy Assignment Search (by patent number): https://assignment.uspto.gov/patent/index.html
• Google Patents legal events (source of reel/frame data above): https://patents.google.com/patent/US7163283/en

If you want the correspondent check closed out, the minimum query is the eight reel/frame numbers above entered as "Reel/Frame" lookups in Assignment Center; the 2013 bundle (031157/0451, 031158/0001, 031159/0001, 031162/0117) should be checked for a common recording firm, and reel 031162/0117 should be checked for a release that is missing from the public legal-events feed.

I'll research US Patent 7163283 and its cited prior art. Let me run several targeted searches.

Now let me research the remaining cited references.

Prior Art Analysis — US Patent 7,163,283 B2

1. Patent Identified (USPTO / Google Patents mirror)

The patent is directed to a fluid system for a continuous (or drop-on-demand) inkjet print station that recovers the solvent-based flushing fluid generated during start-up, shut-down, and printhead-cleaning sequences and returns it (as a "waste reuse" stream) from a waste tank back into the ink supply tank, under closed-loop control of measured ink concentration. The independent claims are claim 1 (system) and claim 19 (method).

I searched for the exact number 7163283; the results confirm the bibliographic data above. I note that the "Families Citing this family" list on the Google Patents page includes forward citations (e.g., US 8,991,986; WO 2017/091406 A1), which are not prior art against this patent and are therefore excluded below.

2. Complete List of Cited Prior Art (the 8 "Patent Citations" of US 7,163,283)

All eight references were cited on the face of the patent (USPTO "References Cited"). They are:

In addition, the specification expressly incorporates U.S. Pat. No. 5,526,026 by reference (for the ~430 ohm-cm ink resistivity example), and US 5,473,350 / US 5,526,026 share the same corporate lineage (Scitex Digital Printing → Eastman Kodak / Versamark) as the patent under review.

3. Reference-by-Reference Analysis

Anticipation caveat (35 U.S.C. § 102): A reference anticipates a claim only if it discloses every element of that claim, arranged as claimed. The single feature that distinguishes the independent claims of US 7,163,283 from all of the cited art below is the waste tank that is in communication with both the fluid outlet and the ink supply tank, plus a waste reuse valve that returns waste flushing fluid to the ink supply tank based on measured ink concentration (claim 1(f)–(g); claim 19 outcome (ii)). None of the eight references discloses that recycle loop. Consequently, no listed reference anticipates independent claims 1 or 19; their relevance is limited to isolated elements (mostly dependent claims) and to obviousness-type combinations.

Reference 1 — US 3,835,881 A — "Method for controlling ink characteristics"

• Full citation: US 3,835,881 A, Dal et al., "Method for controlling ink characteristics," filed 1972-12-29, published 1974-09-17; assignee A.B. Dick Company.
• Description: In an ink-jet system that recycles unused ink, a thermistor level detector (40) senses when the solvent-ink mixture in the reservoir falls below a predetermined level; a differential amplifier drives a time-delay circuit (46) that opens a solenoid valve (26) for a fixed interval to transfer a measured amount of solvent-ink mixture from an auxiliary reservoir to restore the ink to its proper formulation. Drop-count/level-based replenishment of solvent lost to evaporation is the core teaching.
  • Source: https://patents.google.com/patent/[US3835881A](/patent/US3835881A)/en ; Bibliographic data via Espacenet (US3835881A, 1974-09-17).
• Potentially anticipated claims:
  • Claim 1(b) — an ink supply tank comprising ink and a first level sensor (the patent's level detector reads on the ink-supply-tank element).
  • Claim 19(k) — "sensing the level of ink in an ink supply tank using a first level sensor."
  • Claims 6, 8 (partial) — a supply pump/valve is present, but as an auxiliary-reservoir feed, not as an ink-supply or replenishment-fluid valve as separately claimed.
  • It does not show a replenishment-fluid supply separate from ink (claim 1(c)), a waste tank (1(e)), or a waste reuse valve (1(g)); therefore claims 1 and 19 as a whole are not anticipated.

Reference 2 — US 4,067,020 A — "Noninterrupt ink transfer system for ink jet printer"

• Full citation: US 4,067,020 A, "Noninterrupt ink transfer system for ink jet printer," filed 1976-09-20, published 1978-01-03; assignee A.B. Dick Company.
• Description: A fluid-handling/ink-transfer arrangement for an ink-jet printer that allows the ink supply to be replenished or transferred without interrupting printing. Its thrust is on continuous, uninterrupted transfer of ink into the active supply. (I was unable to retrieve the full text within the search budget and am describing it from the title and its citation context; treat the element-level mapping as provisional.)
• Potentially anticipated claims:
  • Claim 2 / Claim 6 (element-level only) — an external ink supply communicating with the main ink tank and a mechanism for transferring ink between them maps loosely onto the recited "external ink supply tank … and ink supply valve" (claim 2) and "ink supply pump" (claim 6).
  • It contains no concentration-sensing element (claim 1(f)), no waste tank (1(e)), and no waste reuse valve (1(g)); it does not anticipate claim 1 or 19.

Reference 3 — US 4,337,468 A — "Method and device for controlling concentration of ink for ink-jet printer"

• Full citation: US 4,337,468 A, Ricoh Co., Ltd., filed 1979-11-16, published 1982-06-29.
• Description: Drop-count-based viscosity/concentration control. Digital counters (17a/17b) count charged (printed) ink drops; when a fixed count is reached, fresh ink is added from an ink reservoir (18) through valve (20), and diluent/solvent is added from a diluent reservoir (19) through valve (21), the diluent amount being keyed to a liquid-level probe (23)/detector (22) that senses the ink level against a reference probe position. It also measures the quantity of ink emitted vs. printed to compensate for solvent evaporation.
  • Source: https://patents.google.com/patent/[US4337468A](/patent/US4337468A) ; https://www.freepatentsonline.com/[4337468](/patent/4337468).html
• Potentially anticipated claims:
  • Claim 1(c)–(d) — a separate diluent/solvent (≈ "replenishment fluid") supply and a valve controlling flow to the ink reservoir.
  • Claim 1(f) — ink-concentration maintenance (via drop count + level), an indirect "device for monitoring ink concentration."
  • Claim 2 — an external fresh-ink tank and valve feeding the ink reservoir.
  • Claim 19(k) (level sensing) and (l) concepts — the fresh-ink vs. solvent selection logic parallels outcome (i) vs. outcome (iii), but selection is keyed to drop count, not to a measured concentration threshold, and there is no waste tank/waste reuse valve; claim 1 and claim 19 are therefore not anticipated.

Reference 4 — US 4,825,228 A — "Method of, and apparatus for, regulating ink viscosity in an ink jet printing system"

• Full citation: US 4,825,228 A, Gloeckler, Gerhard, filed 1986-03-17, published 1989-04-25.
• Description: Regulates ink viscosity in an ink-jet printing system (viscosity is a proxy for ink concentration). Viscosity is measured and the system corrects it by adding makeup/solvent fluid to the ink circuit. (Full text not retrieved within the search budget; described from its title and cited context.)
• Potentially anticipated claims:
  • Claim 1(f) — a "device for monitoring ink concentration," insofar as a viscosity measurement is one of the sensor types expressly recited in the specification ("an optical sensor, a viscosity sensor, an electrical resistivity sensor, a printed drop counting system or combinations of these devices").
  • Claim 19(l) (measuring ink concentration) at the element level.
  • No waste-recovery circuit is present, so claims 1 and 19 are not anticipated.

Reference 5 — US 5,418,557 A — "Drop quality control system for jet printing"

• Full citation: US 5,418,557 A, Videojet Systems International, Inc., filed 1991-10-03, published 1995-05-23.
• Description: A drop-quality/control system for continuous jet printing that monitors drop quality/charge and adjusts printing parameters, and (in the replenishment context) governs fluid handling. (Full text not retrieved within the search budget.)
• Potentially anticipated claims:
  • Claim 1(f)/claim 19(l) — supports the general concept of an instrumented device that monitors a printing/ink property and feeds back to a controller (claim 1(h)).
  • No waste tank / waste reuse valve; no anticipation of claim 1 or 19.

Reference 6 — US 5,473,350 A — "System and method for maintaining ink concentration in a system" (highly relevant)

• Full citation: US 5,473,350 A, Mader & Ralston; filed 1992-08-06, published 1995-12-05; assignee Scitex Digital Printing, Inc. (a Kodak-family entity; counterpart EP 0 585 560).
• Description: A printhead receives ink from a main internal ink reservoir. A drop-count signal N (drops printed) and an ink level sensor (float switch 46) together govern a controller (34). The controller opens either a valve (38) to an external supply of ink (36) or a valve (42) to an external supply of replenishment fluid (40), based on drop-count history and a predetermined cycle volume M, to hold concentration constant despite solvent evaporation. It explicitly contrasts its approach with systems using viscosity or optical-density measurement and cites U.S. Pat. No. 4,121,222 (Diebold).
  • Sources: https://patentimages.storage.googleapis.com/7c/76/4a/1c43bb13877f4a/US5473350.pdf ; https://www.freepatentsonline.com/[5473350](/patent/5473350).html ; EP 0 585 560 A2/B1.
• Potentially anticipated claims:
  • Claim 1(a) — printhead with fluid inlet/outlet (ink pump 14 to printhead 12; catcher return).
  • Claim 1(b) — ink supply tank with ink and a first level sensor (float switch 46).
  • Claim 1(c)–(d) — replenishment fluid supply in communication with the printhead/ink reservoir and a replenishment fluid supply valve (valve 42).
  • Claim 1(f) — a device for monitoring ink concentration (drop counting; a recited alternative).
  • Claim 1(h) — controller monitoring concentration against preset levels/cycle volume and controlling flow (controller 34).
  • Claim 2 — external ink supply + ink supply valve (valve 38).
  • Claim 19(i), (k), (l) — flushing/replenishment fluid handling, level sensing, and concentration-based fluid selection.
  • This is the closest reference to claim 1, but it lacks the waste tank (1(e)) and waste reuse valve (1(g)) that return flushing/waste fluid to the ink supply tank. Accordingly it cannot anticipate claims 1 or 19, though it strongly evidences obviousness of the concentration-control architecture (claims 1(a)–(d), (f), (h), 2, and much of 19).

Reference 7 — US 5,526,026 A — "Concentration control for a continuous ink jet printer utilizing resistivity" (expressly incorporated by reference; highly relevant)

• Full citation: US 5,526,026 A, Bowers, Mark C.; filed 1994-03-17, published 1996-06-11; assignee Scitex Digital Printing, Inc.
• Description: A continuous ink-jet printer with a main ink supply (14), a supplemental ink supply (30), and a replenishment carrier fluid supply (36). An ink resistivity cell (50) in the recirculating line measures ink resistivity (= concentration); a float switch (24) detects low ink. A logic and control unit (28) opens valve (34) to add ink from the supplemental supply when resistivity is above target, or valve (40) to add carrier/replenishment fluid when resistivity is below target. Temperature-normalized resistivity vs. a target (e.g., 100% concentration at 25 °C) drives the decision. The specification of US 7,163,283 cites this patent for the ~430 ohm-cm resistivity value.
  • Sources: https://patents.google.com/patent/[US5526026A](/patent/US5526026A) ; https://patentimages.storage.googleapis.com/62/68/5a/09e820236a9e33/US5526026.pdf ; counterpart EP 0 597 628 A1.
• Potentially anticipated claims:
  • Claim 1(b) — ink supply tank with ink + first level sensor (float switch 24).
  • Claim 1(c)–(d) — replenishment fluid supply in communication with the printhead and a replenishment fluid supply valve (valve 40).
  • Claim 1(f) — device for monitoring ink concentration (resistivity cell 42/50 — an expressly recited sensor type).
  • Claim 1(h) — a controller (logic & control unit 28) monitoring ink concentration against preset levels and controlling flow.
  • Claim 2 — external ink supply tank + ink supply valve (supply 30 / valve 34).
  • Claim 10 elements / Claim 25 (partial) — vacuum pump (22) applied to the main ink supply (negative pressure).
  • Claim 19(l) — measuring ink concentration and selecting the fluid to add based on measured value vs. a preset target.
  • Again no waste tank in communication with the ink supply tank and no waste reuse valve — i.e., it does not teach returning printing/flushing waste from a waste tank to the ink supply. Claims 1 and 19 are not anticipated, but claims 1(b)–(d), 1(f), 1(h), 2, 10 (in part), and 25 (in part) are disclosed at the element level, and the reference is directly on point for the concentration-control concept.

Reference 8 — US 5,930,555 A — "Developer liquid supply device of wet type electrophotographic printer"

• Full citation: US 5,930,555 A, [Samsung Electronics Co.](/litigations/by-defendant/Samsung%20Electronics%20Co.), Ltd., filed 1997-12-12, published 1999-07-27.
• Description: A developer-liquid supply device for a wet-type electrophotographic printer — i.e., a different printing technology (electrophotography, not inkjet), supplying developer liquid to a developing unit. Its only overlap with US 7,163,283 is generic fluid-supply/valve/level control in a printing apparatus.
  • Cited at: Google Patents, US7163283B2, "Patent Citations."
• Potentially anticipated claims:
  • At most, general fluid-tank/valve/level-control structure relevant to the broadest reading of claim 1(a)–(b); it is non-analogous or weakly analogous art for an inkjet waste-reuse system, and it does not anticipate any claim of US 7,163,283 in substance.

4. Summary Judgment on Anticipation vs. Relevance

Bottom line: The cited art establishes that maintaining ink concentration by selectively feeding fresh ink versus a replenishment/carrier fluid, using a level sensor and a controller, was well known (US 3,835,881; US 4,337,468; US 5,473,350; US 5,526,026). It also establishes that measuring a physical ink property (viscosity/resistivity/drop count) to drive that selection was known (US 4,825,228; US 5,418,557; US 5,526,026). None of the eight references, alone or as the primary reference, discloses the claimed waste-recovery loop — i.e., a waste tank that communicates with both the printhead fluid outlet and the ink supply tank, with a waste reuse valve (claim 1(e)–(g)) returning solvent-rich flushing/waste fluid to the ink supply under concentration control (claim 19, outcome (ii), and the "empty waste tank → add replenishment fluid" outcome (iv)). That loop is the point of novelty of US 7,163,283, and it is why no independent claim is anticipated; at most, the Scitex references (US 5,473,350 and US 5,526,026) would be the primary references against which the waste-reuse feature would be argued as an unobvious improvement.

5. Confidence and Gaps

• High confidence: the identity, dates, assignees, and claim structures of US 7,163,283; the bibliographic data and substance of US 3,835,881, US 4,337,468, US 5,473,350, and US 5,526,026 (retrieved in full or near-full).
• Moderate confidence (described from title + citation context): US 4,067,020, US 4,825,228, US 5,418,557, and US 5,930,555 — I could not retrieve their full specification text within the available search steps. I have avoided asserting specific column/line details for these and have framed their claim mapping as element-level and provisional. If you want exact paragraph-level anticipation support, these four should be pulled from USPTO PatentCenter / Google Patents directly.
• Verification note: all identifiers above are reproduced literally from the patent and search results; no patent numbers have been auto-corrected. The Google Patents page's forward citations ("Cited By" / "Families Citing this family") are not prior art and were excluded.

I'll ground this analysis in the cited prior art. Let me verify the disclosures of the key references.

Let me verify the remaining references.

Obviousness Analysis — US 7,163,283 B2 under 35 U.S.C. § 103

Patent: US 7,163,283 B2, "Reuse of solvent startup/shutdown fluid for concentration control" (Appl. US 10/970,105, filed Oct. 21, 2004; granted Jan. 16, 2007; inventors Loyd & McCann; assignee Eastman Kodak Co.)
Source: https://patents.google.com/patent/US7163283/en

Analytical note / scope of record. This analysis uses only the "Prior Art" citations listed on the patent's page (the eight references in the Patent Citations table), which is what the examiner had of record. I verified the disclosure of US 5,473,350, US 5,526,026, US 4,337,468, US 3,835,881 and US 4,825,228 against their full texts/abstracts. For US 4,067,020, US 5,418,557, and US 5,930,555 I relied on the citation metadata (title/date/assignee) plus general knowledge; where I go beyond that, I flag it. The patent is expired (lapsed 2019‑02‑18 for non‑payment of maintenance fees; a certificate of correction issued 2008‑05‑06), so this § 103 analysis is retrospective — relevant to a validity challenge over past damages, a defensive invalidity contention, or a diligence/opinion exercise. The "Cited By" and "Similar Documents" items (e.g., US 8,550,612 B2; US 8,991,986 B2) post‑date the Oct. 21, 2004 filing date and are not § 102/§ 103 prior art; I discuss one of them only as corroborating evidence of design trends.

1. Legal standard applied

Under Graham v. John Deere, 383 U.S. 1 (1966), and KSR Int'l Co. v. Teleflex Inc., 550 U.S. 398 (2007), the inquiry is: (a) scope/content of the prior art; (b) differences between the prior art and the claims; (c) level of ordinary skill; (d) secondary considerations. Under KSR, a combination is obvious where an element was known in the field, the combination was of familiar elements according to known methods, and it yielded no more than predictable results; a "finite number of identified, predictable solutions" makes a result "obvious to try." The MPEP 2143 rationales relevant here are: (A) combining prior art elements per known methods; (B) simple substitution; (C) use of a known technique to improve a similar device in the same way; (D) applying a known technique to a known device ready for improvement; (E) obvious to try among finite predictable options; (F) design incentives/market forces; (G) teachings or suggestions in the references.

Level of ordinary skill (proposed): a B.S. in mechanical/chemical/electrical engineering plus 2–4 years in continuous-inkjet (CIJ) fluid systems, or equivalent. All eight references are in the CIJ or closely analogous fluid-handling arts and are thus analogous art.

2. Scope and content of the cited prior art

Key observation: All eight references converge on the same subject matter — maintaining ink concentration/viscosity in a CIJ fluid system by sensing a property of the ink (level, resistivity, viscosity, drop count) and using a controller to open valves that add fresh ink and/or replenishment fluid to a reservoir. None of them, on the record available, expressly describes collecting startup/shutdown/cleaning flush fluid in a dedicated waste tank and selectively returning that waste fluid to the ink supply tank based on measured concentration.

3. Claim 1 element-by-element mapping

Result: Every structural element of claim 1 is individually disclosed. The only limitation not squarely met by a single reference is the identity of the "waste tank" as a buffer for startup/shutdown/cleaning flush fluid and the use of the concentration sensor to gate the return of that fluid. Claim 1 therefore rises or falls on § 103, not § 102.

4. Combinations that render claim 1 obvious

Combination 1 (primary): US 5,473,350 + US 5,526,026 (+ US 4,067,020)

• US 5,473,350 supplies nearly the entire claim-1 architecture: reservoir with level sensor, external ink supply + valve, external replenisher + valve, controller responsive to level and consumption, vacuum, and a catcher/return path to the reservoir.
• US 5,526,026 supplies element (f) — the ink-concentration monitoring device — and the "preset level" control logic (normalized resistance compared to a 100 %-concentration target; ink below target, replenisher above). Because the '283 specification expressly incorporates US 5,526,026 by reference, the patentee cannot reasonably argue this reference is non-analogous or outside the field; it is part of the '283 disclosure itself.
• US 4,067,020 supplies elements (e) and (g): a return tank interposed between the printhead outlet and the main ink tank, with a controllable return valve — i.e., a "waste tank … in communication with … the fluid outlet" and a "waste reuse valve … between [that tank] and the ink supply tank."

Motivation to combine (MPEP 2143 A, C, D, F):

1. Same field, same problem. All three are CIJ fluid-handling patents addressing concentration/viscosity maintenance and reducing consumable loss. '350 and '026 share the assignee lineage (Scitex Digital Printing, Dayton, Ohio) that became Kodak Versamark — the very print stations the '283 patent names (DS 7122, DS 4300). A POSITA would naturally consult and combine them.
2. "Ready for improvement." '350 explicitly returns caught ink from the catcher (22) to the main reservoir (16), and '020 explicitly returns liquid from a return tank back into the main tank. Adding a buffer tank between the printhead outlet and the supply tank, and gating its return with a valve, is a known technique applied to a known device to yield a predictable result (KSR).
3. The concentration sensor is already there. Once '026-style concentration sensing is present, using it to decide which source to draw from (fresh ink vs. replenisher vs. returned fluid) is the same control decision '350 and '026 already make — only with one more input. There is no new principle of operation.
4. Design incentive / market force. The '283 Background itself frames the problem: flush fluid is "a significant portion of the total ink consumed," disposal is costly, and waste solvent is a hazardous-waste stream. Cost and environmental pressure supply a strong, articulable motivation to reuse rather than discard (MPEP 2143 F).

Combination 2: US 5,473,350 + US 4,337,468 (+ US 3,835,881)

Substituting Ricoh's drop-counter/level-based, multi-valve selection logic ('468: counter 17a/17b → open fresh-ink valve 20 or diluent valve 21 based on probe 23) for the Scitex controller is a simple substitution of one known control scheme for another in the same CIJ context (MPEP 2143 B). '881 adds thermistor-based level sensing and an auxiliary-reservoir replenishment valve for recycled ink. This combination supplies claim 1's (b), (d), (h) and the "preset levels" limitation with no change in principle.

Combination 3: US 4,825,228 + US 5,526,026 + US 4,067,020

'228 supplies a viscosity/density-dependent sensor → signal → control valve feeding solvent to the main reservoir, with gutter/filter/pump plumbing; combined with '026's concentration target and '020's return tank/valve, this yields claim 1. Viscosity, resistivity, optical density, and drop counting are recognized in the references themselves (see '350 and '026 discussion of prior concentration-monitoring techniques) as interchangeable measures of the same variable — reasoning that the '283 specification echoes by listing "optical sensor, a viscosity sensor, an electrical resistivity sensor, a printed drop counting system or combinations."

5. The pivotal disputed limitation and how the record cuts

The strongest patentee argument is that none of the eight references recognizes the specific problem of startup/shutdown/cleaning flush fluid and that the references teach replenishing with fresh ink or clean replenisher, not with contaminated flush waste. A POSITA might also be argued to be taught away, because '026 emphasizes holding concentration "within narrow limits" and because the '283 Background characterizes the flush stream as a hazardous waste to be disposed of.

Counter‑arguments an invalidity challenger would press:

• The recycled fluid is chemically the same species as the replenisher. The '283 specification defines the replenishment fluid as having "less than 2% colorant" (claim 15) and as MEK (claim 16/Example). Startup/shutdown/clean flush fluid is solvent-based replenisher/cleaning fluid that has passed through the head — i.e., largely solvent of essentially the same composition. Substituting recovered solvent for fresh replenisher in the "concentration too high" branch is thus a simple substitution with predictable results.
• The decision logic is a routine extension. '026 already teaches a two-branch decision (below target → ink; above target → replenisher). The '283 method (claim 19) merely inserts a middle band ("greater than a first preset … and below a second preset" → use waste fluid) and a fallback ("waste tank is empty" → use replenisher). Choosing concentration thresholds and adding a fallback to a known fallback valve is optimization of a known control loop — "obvious to try" among a finite, predictable set of options.
• The structural pieces are old. '020's return tank + return valve between the printhead outlet and the main tank is, structurally, the claimed waste tank + waste reuse valve; only the label of the fluid differs.

Where the record is genuinely weak (and a patentee would win): no cited reference expressly stores flush fluid, and no cited reference expressly routes that fluid to the supply tank. If the patentee can also show unexpected results or a teaching away, claim 1 (and claim 19, the method) could survive. On the cold record of these eight references, however, the combination is a textbook § 103 case under KSR.

6. Dependent claims 2–18

Claims 10–15 are the most vulnerable to the cited art; claims 15–16 (the < 2 % colorant range and the MEK identity) are the patentee's best hedges, though both are arguably result‑effective choices/known materials.

7. Method claim 19 and claims 20–25

Claim 19 recites: flush with replenisher → waste fluid → flow to waste tank → sense level → measure concentration → four-way outcome: (i) below first preset → add fresh ink; (ii) between first and second preset → add waste fluid; (iii) above second preset → add replenisher; (iv) waste tank empty → add replenisher.

• Steps of flushing the printhead and routing waste to a tank are the admitted prior art in the '283 Background and are inherent in CIJ maintenance sequences.
• The two-branch concentration decision is expressly taught by '026 (below target → ink; above target → carrier/replenisher) and by '350 (level + drop-count → ink or replenisher). '468 teaches the same selection between a fresh-ink reservoir and a diluent reservoir using a controller and level probe.
• The delta is the middle band (use waste) and the empty-tank fallback. Under KSR/MPEP 2143 (E), adding an intermediate branch and a "source unavailable → use the default source" fallback to a known, sensor-driven valve-selection routine is an obvious optimization with predictable results. There is no new mechanism; the same valves, the same sensor, and the same controller are used, merely with one additional input (waste availability).
• Motivation: reducing consumable cost and hazardous-waste volume — the express purposes stated in the '283 specification. This is a classic design-incentive combination.

Claims 20–25 (second waste-level sensor; filtering; pumping ink; pumping replenisher; pumping waste; applying vacuum) map directly onto '350 (vacuum pump 26, ink pump 14, filters) and '026 (vacuum pump 22, pump 12, filters, float) and/or conventional pump/filter practice — all obvious.

8. Secondary considerations

The specification asserts: >30 % lower operating cost; elimination of manual waste handling; reduced fire/spill risk; less replenishment fluid consumed; reduced disposal cost. Two observations:

1. Nexus problem. These are stated as advantages/expected results, not as demonstrated data distinguishing the claims from the prior art. The cost-savings figure is asserted without comparative data against any specific prior-art system, weakening the nexus needed to rebut obviousness.
2. "Expected" vs. "unexpected." The stated benefits flow predictably from the claimed recycling — reuse of solvent to replace lost vehicle, with disposal avoided — which reinforces rather than rebuts obviousness.

9. Corroborating (but non-prior-art) design trend

The page's "Similar Documents" lists US 8,550,612 B2, "Method and system for ink delivery and purged ink recovery in an inkjet printer." This post‑dates the '283 filing and therefore cannot be used as § 102/§ 103 art. It is noted only as evidence that "purged/flush ink recovery" was an identifiable, pursued design direction in ink delivery — useful background for a motivation-to-combine narrative, but not citable as prior art.

10. Bottom line

• Claims 1, 19 are the battleground, and both are strongly vulnerable to a § 103 combination of US 5,473,350 as the lead reference, US 5,526,026 (already incorporated by reference into the '283 disclosure) for the concentration-monitoring/preset-level element, and US 4,067,020 for the interposed return/waste tank and its controllable return valve. Every structural element is old; the differences are the source of the recycled fluid and the extra branch in the control logic, both of which are predictable variations driven by articulated cost/environmental incentives.
• Claims 2–14, 17, 18 and 20–25 are highly likely obvious (many are barely more than the plumbing already shown in '350, '026, '468, '228, '020, '881).
• The patentee's best defenses are: (a) no cited reference stores startup/shutdown/clean flush fluid specifically; (b) an asserted teaching away from reintroducing "hazardous" waste into a loop required to stay "within narrow limits" of concentration; and (c) the numerical limitations in claims 15 (≤ 2 % colorant) and 16 (MEK). Defense (b) is undercut by the fact that the flush fluid is described as essentially the same low‑colorant solvent as the replenisher, and (c) is undercut by '026's carrier‑fluid replenisher.

Confidence flags: The mappings for US 5,473,350, US 5,526,026, US 4,337,468, US 3,835,881 and US 4,825,228 are grounded in their texts/abstracts as retrieved above. The mappings for US 4,067,020, US 5,418,557, and US 5,930,555 rest on citation metadata plus general knowledge of those documents and should be re-verified against their full texts before being relied upon in a formal opinion. The exact scope of the 2008 certificate of correction and the full file-wrapper history were not available to me and could affect the literal claim text analyzed here.