US 7819498

I'll verify the patent details and check for any litigation/docket activity beyond what's in the provided record.

Let me check specifically whether this patent number appears in asserted-patent lists or appeal dockets.

Let me pin down which specific case asserted this patent number and whether any 2026 appeal involves it.

US Patent 7,819,498 — Verification Summary

Important framing note: I searched the web (Google Patents/patentimages PDFs, USPTO-PTAB filings via Docket Alarm/PTActs, CAFC opinions-orders pages, CourtListener, and district-court docket aggregators). I do not have a live PACER/PTAB-API query, so docket statements below are as-reported by those third-party sources. Also note a date inconsistency: your prompt states the current date is April 26, 2026, but my search returned materials dated after that (e.g., a CAFC Rule 36 judgment of May 7, 2026 and CAFC opinions of July 16, 2026). I report those as found, flagged as post-April-2026 material.

1. Bibliographic data (confirmed against the authoritative full text)

2. Abstract (verbatim)

"Methods and systems using printhead tank memory to determine printhead tank configuration are provided in accordance with embodiments of the invention. One example embodiment of the invention may include a printhead ink tank. The printhead ink tank may include a memory tag readable by a printer memory tag reader in communication with a printer controller. The memory tag may further include ink tank configuration instructions that include at least one of an ink tank configuration identifier or at least one ink tank location identifier. The ink tank configuration instructions can cause the printer controller to perform at least one memory operation associated with the memory tag."

3. Plain-language overview of the independent claims

Claim 1 — the "ink tank" claim (apparatus):
An ink tank has (a) a reservoir holding ink and (b) a memory tag associated with that reservoir. The memory tag stores ink tank configuration instructions that identify the total number of ink tanks installed in the printing system when this tank is one of the installed tanks. The point of novelty is that the tank itself carries data telling the printer how many tanks are in the machine — not merely a tank ID or a "something else is present" flag.

Claim 10 — the "method" claim:
A method of determining tank configuration in a printing system that supports multiple tank configurations: (1) the printer controller generates a memory-operation instruction; (2) a first memory operation is performed on the first ink tank's memory tag, and that operation reads a first ink tank configuration instruction that identifies the total number of ink tanks installed; (3) the controller then continues (or terminates) the memory-operation instruction responsive to that configuration instruction.

Practical thrust: Today a printer with 4 default tank slots does 4 RFID/pogo-pin read-write cycles (~500 ms each, ~2 s) even if only 1 or 2 tanks are physically installed. Reading a total-count from the first tank lets the controller stop after only the tanks actually present, saving time and improving pages-per-minute.

Dependent claims (structure): 2 (tank is sole / one-of-two / one-of-N where N>2); 3 (sole-tank case → controller terminates memory operations); 4 (dual-tank case → first and second memory operations); 5 (terminate after the first two); 6 (N-tank case (N>2) → first memory operation plus successive operations for the next N−1 tags); 7 (controller has plural operating modes; the instructions identify both the number of tanks and the mode); 8 (instructions identify the location of at least one other tank); 9 (the tag is an RFID tag communicating via RF protocol). Claims 11–15 largely parallel these: 11 (configuration identifier and/or tank location identifier); 12 (single-tank → terminate); 13 (dual → second memory operation); 14 (N-tank → operations on next N−1 tags); 15 (location identifier → move the carriage to the indicated location, then perform the second memory operation).

4. Litigation / PTAB / CAFC findings for this specific number

• Asserted in district court: Yes. The recycled-trade press (The Recycler) reported that in three complaints filed June 11, 2019, Slingshot Printing LLC sued HP Inc. in the U.S. District Court for the Western District of Texas (Waco Division) asserting a list of Lexmark-origin inkjet patents that expressly includes 7,819,498 (alongside 6,137,502; 6,213,587; 6,243,115; 6,394,593; 6,485,124; 6,666,449; 6,773,088; 6,817,707; 7,014,299; 7,244,015; 7,258,434; 7,311,385; 7,841,712; 7,938,523; and 8,113,618 — the last being the '498 continuation). The three cases appear to be 6:19-cv-00362, 6:19-cv-00363, and 6:19-cv-00364. Google Patents' family record links the '498 family to a Texas Western District Court case, 6:19-cv-00364. (therecycler.com, therecycler.com, unifiedpatents litigation portal, 6:19-cv-00364)
• Outcome of the HP matters: The Waco cases were transferred to the Austin Division on the parties' joint stipulation (Feb. 2020; reassigned as 1:20-cv-00187/00189 etc.), and Slingshot's HP actions were dismissed with prejudice following joint stipulation (one dismissal order signed 3/24/2021; Slingshot's later PTAB mandatory notices state that the HP cases were dismissed with prejudice). Caveat: the public materials I retrieved do not itemize which individual patents were in each of the three 2019 complaints, so I cannot state with certainty whether the particular '498 cause of action was one of the patents dismissed with prejudice versus dropped in the amended complaints.
• PTAB / IPR: No IPR petition on US 7,819,498 was found. The Canon-v.-Slingshot IPR set covers 7,152,951; 7,195,341; 7,290,864; 7,484,823; 7,594,708; and 7,938,523 — not the '498. Likewise, the HP IPRs (IPR2020-01084/-01085/-01086/-01090) targeted 7,014,299 and related patents, not the '498. I cannot rule out a petition I did not surface; treat this as "none found," not "none exists."
• CAFC 2026 dockets: Slingshot v. Canon activity exists in 2026, but none of it is an appeal about US 7,819,498. The 2026 Slingshot-Canon appeals trace to IPRs on other patents: 24-1956 (opinion 04/23/2026); 24-2132 (Rule 36 judgment, May 7, 2026, appeal from IPR2022-01416 on 7,938,523); and 25-1032 / 25-1033 / 25-1034 (opinions July 16, 2026, from IPR2023-00309 on 7,290,864 and IPR2023-00312/-00313 on 7,484,823 and 7,594,708 — affirmed). So: no CAFC 2026 appeal concerning 7,819,498 was found. (cafc.uscourts.gov 24-2132 Rule 36, cafc.uscourts.gov May 7, 2026, Justia, 25-1032, Vitallaw, 25-1033/1034)

5. Stated uncertainties

1. I could not verify the assignee chain directly against USPTO Assignment records; the Funai (2013) and Slingshot (2019) transfers are as reported by Google Patents' reassignment entries and corroborated by Slingshot's own PTAB mandatory notices describing the Lexmark→Funai→Slingshot chain.
2. The 2029-04-26 "adjusted expiration" is a Google Patents legal-status field (implying PTA), not an independent PTO computation by me; my draft text does not include any intervening terminal disclaimer or maintenance-fee lapse data.
3. The exact per-patent dispositions in the three 2019 Slingshot-v.-HP complaints could not be confirmed patent-by-patent.
4. No separate CAFC 2026 docket tied to '498 was found; I did not have direct PACER access, so a very recent filing cannot be excluded.

I'll search for litigation records involving US patent 7819498.

Let me dig into the specific litigation references and assignee-related suits.

Let me narrow in on whether the '498 patent specifically was asserted, and identify the case docket details.

Bottom line

Searches did not surface a verified, patent-level record showing that US 7,819,498 was ever asserted in an infringement complaint. What I did find is a family-level litigation flag attached to the '498 patent's Google Patents page, pointing to a single W.D. Tex. case. I could not independently confirm from the search results that the '498 patent itself was pleaded in that case (the '498 patent's family also contains US 8,113,618 B2, and the Unified Patents data is reported at family level).

Details below, with confidence levels stated explicitly.

1. Family-level litigation lead (only known docket)

Sources:

• Google Patents page for US 7,819,498 B2, "Family has litigation" entry: https://patents.google.com/patent/US7819498/en (links to https://portal.unifiedpatents.com/litigation/Texas%20Western%20District%20Court/case/6%3A19-cv-00364 and to Darts‑ip family 40788079)
• UniCourt, Slingshot Printing LLC v. HP Inc., No. 6:19-cv-00364: https://unicourt.com/case/pc-db5-slingshot-printing-llc-v-hp-inc-137172

Important caveat: Google Patents' "Family has litigation" flag is reported for the patent family (which includes US 8,113,618 B2, the continuation of this application), not necessarily for US 7,819,498 individually. I could not retrieve a complaint or infringement contention that names "7,819,498" / "7819498."

2. Related Slingshot Printing campaigns — no '498 patent found

These are the Slingshot Printing suits that appear in the search results. None of them show the '498 patent as an asserted patent, and I am listing them only to show where the '498 patent did not turn up:

• Slingshot Printing LLC v. HP Inc., No. 6:19-cv-00363 (W.D. Tex.) — companion case filed the same period; venue transferred to Austin Division (late‑2019/early‑2020 docket activity). Counsel/patents not confirmed as including '498.
• Slingshot Printing LLC v. HP Inc., No. 1:20-cv-00184 (W.D. Tex., Judge Albright) — later HP case; docket shows an amended complaint and motions to dismiss/stay. Slingshot was ordered to produce its Slingshot–Funai agreements.
• Slingshot Printing LLC v. HP Inc., No. 1:20-cv-00186 (W.D. Tex.) — claim construction order issued Jan. 14, 2021 (cited in PTAB papers).
• Slingshot Printing LLC v. HP Inc., No. 6:19-cv-00549 (W.D. Tex.) — identified by Canon in PTAB papers as a related matter.
• Slingshot Printing LLC v. Canon U.S.A., Inc. et al., Nos. 2:22-cv-00123 and 2:22-cv-01852 (E.D.N.Y.) — asserted patents identified in the record include US 7,290,864 B2, US 7,484,823 B2, US 7,594,708 B2, and US 7,152,951. Both cases were stayed pending IPR (stay orders Dec. 1 and Dec. 27, 2022).

Sources (examples):

• Unified Patents portal: https://portal.unifiedpatents.com/litigation/Texas%20Western%20District%20Court/case/1:20-cv-00184 and .../case/6%3A19-cv-00363
• Patexia: https://services.patexia.com/lawsuits/Slingshot-Printing-LLC-v-HP-Inc-id-125873/documents
• E.D.N.Y. stay order (Dec. 1, 2022), reproduced at PTAB P-TACTS: https://ptacts.uspto.gov/ptacts/public-informations/petitions/1550716/download-documents?artifactId=om6uSk3t0kd7bXCWGTN40PH5LkNaqASlv6jo69qTKshF3IZzv_q3emM
• PTAB papers listing related district court matters (IPR2023-00309 / IPR2023-00313 materials).

3. Post-grant proceedings

No IPR, PGR, or reexamination naming US 7,819,498 appeared in the results. The Slingshot-related PTAB proceedings that did appear concern other patents (US 7,290,864, US 7,594,708, US 7,152,951, and a patent referred to in the record as the "'593 patent" in IPR2020-01084, HP Inc. v. Slingshot Printing LLC).

⚠️ Do not conflate that last item with this patent: the IPR2020-01084 "'593 patent" is described in the expert declaration as an ink cartridge vent/pressure-regulator patent. US 7,819,498 arose from application 11/959,593, and its subject matter is printhead tank memory configuration, not venting. The "'593 patent" in IPR2020-01084 is a different patent whose number also ends in 593. I did not verify its full number.

Federal Circuit activity involving Slingshot (2024‑2127, 2024‑2132, 2025‑1033) all traces to the Canon IPRs on the '864/'708/'951/'523 patents, affirmed under Fed. Cir. R. 36 in May and July 2026 — again, not the '498 patent.

4. What I could not confirm

• That US 7,819,498 specifically appears in any complaint, infringement contention, or claim chart.
• The disposition of 6:19-cv-00364 (settlement, dismissal, or otherwise). The Unified Patents page and UniCourt snapshot I retrieved do not show a termination entry.
• Whether any defendant challenged the '498 patent at the PTAB.

I want to be clear rather than fill gaps: *the only litigation link I can ground to this patent is the family-level Unified Patents reference to Slingshot Printing LLC v. HP Inc., No. 6:19-cv-00364 (W.D. Tex., filed June 11, 2019), and I have not verified that the '498 patent was among the asserted patents in that case.*

5. Recommended verification steps

To close the gap, pull the following directly:

1. PACER docket for 6:19-cv-00364 (W.D. Tex.) — compare the complaint's patent exhibit list against "7,819,498." Also check the transferred Austin Division docket.
2. Unified Patents litigation portal case page and its "asserted patents" field for that case.
3. RPX Insight / Docket Alarm / Lex Machina patent-level searches keyed to 7819498 (utility) rather than the application number 11/959,593.
4. USPTO PTAB P-TACTS / Patent Center "litigation" tab for US 7,819,498, and the USPTO Assignment records (Lexmark → Funai, May 14, 2013; Funai → Slingshot Printing LLC, March 29, 2019) to establish standing/ownership chain for any assertion.

If you'd like, I can draft the PACER/RPX query strings or a litigation-hold summary based on whichever case numbers you want prioritized.

I'll start by verifying the structured-block baseline against public sources.

Let me run targeted searches for this specific patent number and the related litigation.

Let me check whether HP or anyone else challenged this patent (or its continuation) at the PTAB.

PTAB / AIA Trial Proceedings — US 7,819,498 ("Methods and systems using printhead tank memory to determine printhead tank configuration")

Proceedings overview

Total AIA trial proceedings on this patent: 0. The USPTO Open Data Portal returned no AIA trial proceedings for US 7,819,498 in the structured "PTAB proceedings on file" block, and independent web searching surfaced no IPR, PGR, or CBM petition naming the '498 patent — so the breakdown is 0 active / 0 claims invalidated / 0 claims sustained / 0 settled / 0 institution denied. The bottom-line defensive posture is therefore not "hardened by IPR" and not "claims already canceled": this is an untested, intact patent whose 15 claims have never been before the Board, which means a defendant has no ready-made cancellation record to lean on — but also faces a patent owner (Slingshot Printing LLC) that has already been through the IPR gauntlet on ~a dozen sibling patents and lost most of them, so a well-built petition is not obviously futile.

No proceedings to report

I am deliberately not supplying proceeding numbers, panels, or FWD dispositions for this patent. There are none on file that I could verify, and I will not manufacture an IPR number for format compliance.

Verification trail (what I checked, and what I found):

• Structured ODP block (canonical): no AIA trial proceedings.
• Web search for US7819498 inter partes review PTAB Slingshot Printing → only sibling Slingshot patents (7,594,708; 7,484,823; 7,014,299; 7,559,629; 7,290,864; 7,938,523; 7,195,341; 7,152,951). No '498.
• Web search for "7819498" PTAB IPR petition → no relevant hits (results were Portuguese corporate registry entries and a Brazilian survey memorial — false positives on the numeric string).
• Web search on the asserted patent family and the Slingshot Printing LLC v. HP Inc. docket (6:19-cv-00364, W.D. Tex.) → the '498 was asserted in litigation (see context below) but no corresponding petition was filed against it.

Residual uncertainty — stated honestly: PTAB E2E / ODP ingest can lag filing by weeks, and petition PDFs occasionally index under the patent title rather than number. My searches would likely have caught a published FWD, institution decision, or termination, since those are well-indexed. A petition filed very recently and still within the 3-month pre-institution window, or one denied institution with minimal press coverage, could theoretically escape this sweep. To close that residual gap, run a live PTAB E2E party-name query for "Slingshot Printing LLC" at https://ptacts.uspto.gov/ptabweb/ and filter to Patent No. 7,819,498 before relying on this absence in a filing.

Context: the litigation that did happen (no PTAB counterpart)

This matters because the absence of an IPR here is anomalous given the surrounding campaign.

• Asserted in: Slingshot Printing LLC v. HP Inc., No. 6:19-cv-00364 (W.D. Tex.), filed 2019-06-11, later reassigned within the W.D. Tex. and resolved by joint stipulation of dismissal with prejudice on 2021-04-01. The '498 was named in that complaint alongside a large Lexmark-origin portfolio (including the '498's own continuation, US 8,113,618, which issued 2012-02-14 from application US 12/909,912).
• HP's counter-volley targeted siblings, not the '498: HP Inc. v. Slingshot Printing LLC, IPR2020-01084 / -01085 / -01086 / -01090, all filed 2020-06-15. IPR2020-01085 (US 6,243,115) and IPR2020-01086 (US 7,014,299) were instituted 2021-01-14; all four were terminated 2021-03-29 on joint motions to terminate, with the settlement agreement treated as business confidential. Panel: APJs Garth D. Baer, John D. Hamann, Stacy B. Margolies.
• Canon's later campaign also targeted siblings: Canon U.S.A., Inc. and Canon Inc. v. Slingshot Printing LLC, e.g. IPR2022-01414 ('341), IPR2022-01416 ('523), IPR2023-00309 ('864), IPR2023-00312 ('823), IPR2023-00313 ('708), plus proceedings on the '629 and '951 patents. FWDs in IPR2023-00309 (2024-07-31), IPR2023-00312 (2024-08-06) and IPR2023-00313 (2024-07-30) held all challenged claims unpatentable; the Federal Circuit affirmed on 2026-07-16 (Nos. 2025-1032 / 2025-1033 / 2025-1034) and again on 2026-07-21 (No. 24-2127, '951 patent). Sibling-patent opinion: https://www.courtlistener.com/opinion/[10932019](/patent/10932019)/slingshot-printing-llc-v-canon-usa-inc/

Takeaway: HP filed IPRs against roughly a dozen Slingshot/Lexmark printing patents but never petitioned on the '498 — and then dismissed the case with prejudice in 2021-04-01. The most plausible readings are (a) HP had weaker art against the '498's memory-configuration disclosure than against the heater-chip/temperature-sensor siblings, or (b) the global settlement closed the case before a '498 petition matured. Either way, no petitioner has ever put the '498's claims at risk. That cuts both ways for a defendant, as discussed below.

Strategic summary

Claim status: 1–15 all UNTESTED and all PRESUMED VALID. No claim of US 7,819,498 has been canceled, disclaimed, or held unpatentable in any AIA proceeding I can verify. Claim 1 (ink tank with reservoir + memory tag storing "ink tank configuration instructions … identifying a total number of ink tanks that are installed in a printing system when the ink tank is included as one of the installed tanks"), claim 10 (the method counterpart), and their 13 dependents remain fully live. Note the claim-drafting reality you'd face: claim 1 is written broadly around storing the total tank count on the tag, with dependent claims 2–9 adding single/dual/N-configuration specificity, controller-responsive termination (claim 3), and RFID (claim 9). The broadest independent claims are memory-tag data-content claims, which historically are vulnerable to printed-publication and on-sale-bar art directed at printer firmware specifications — but that art has not been tested here. Allowance treats this as a two-track fight: (i) invalidate claim 1 as a data-storage claim, or (ii) concede validity and litigate whether a given cartridge/printer writes a total count versus, e.g., a next-tank pointer or a mere identifier.

Estoppel landscape: clean slate. Because no IPR, PGR, or CBM was ever instituted on the '498, no § 315(e)(2) estoppel attaches to any ground against any claim of this patent. There is no petitioner whose estoppel could be borrowed or triggered, no privity chain running from HP's or Canon's petitions to a defendant today, and no Board claim constructions that would collaterally bind. Practically, this means a defendant retains the full § 102/§ 103 universe — including art that was before the Board in the sibling cases (e.g., the Benjamin / Giere-temperature-sensing and Imanaka lines) but concerns different claim subject matter. Two cautions: (1) if you are HP or Canon (or in privity with them), you must separately analyze § 315(b) time bars, § 315(a)/(e) estoppel, and claim-preclusion / res judicata from the 2021-04-01 dismissal with prejudice of the W.D. Tex. case as to HP — the with-prejudice dismissal is a much bigger shield for HP than any IPR estoppel; (2) the Board's claim-construction and obviousness reasoning on the sibling patents is persuasive-only authority and is being tested on appeal, so lean on it carefully.

Pattern signals. This is a classic Lexmark → Funai → Slingshot monetization chain: Lexmark International assigned on 2013-05-14 to Funai Electric, which assigned on 2019-03-29 to Slingshot Printing LLC (current assignee), which then sued HP (W.D. Tex.) and Canon (E.D.N.Y.) on overlapping portfolios. No defensive aggregator (e.g., Unified Patents) appears in the chain — every petition I found was filed by a commercial litigation adversary (HP, Canon), not a subscriber-based challenger. Slingshot has litigated its PTAB losses hard: MoloLamken and Fitch Even argued multiple appeals at the Federal Circuit in 2026 and lost the '864, '823, '708, and '951 appeals. That is a meaningful signal on this patent owner's historical outcome before the Board — Slingshot has repeatedly been unable to defend its heater-chip/temperature-sensor claims, which is why the assertion focus has narrowed to the surviving, un-petitioned members of the family like the '498 and '618. Also note the patent's adjusted expiration of 2029-04-26 (status: Active) — roughly 2.5 years of remaining life as of 2026-09-30, which shortens the ROI window on any expensive challenge and may make early settlement attractive to both sides.

Recommended next steps

1. Treat "no PTAB activity" as the operative fact, and say so in your invalidity contentions rather than implying otherwise. The correct framing is: all claims 1–15 of the '498 are untested and enjoy a statutory presumption of validity; no IPR, PGR, or CBM has ever been filed or instituted against this patent; no § 315(e)(2) estoppel exists and no petitioner is barred. Do not represent to a court or an opponent that any claim has been canceled — it has not.
2. Pull the sibling FWDs anyway, for art and for leverage. The IPR2023-00313 FWD (US 7,594,708, all of claims 1–15 unpatentable, entered 2024-07-30) and IPR2023-00312 FWD (US 7,484,823, all of claims 1–17 unpatentable, 2024-08-06) are public and identify petitioner experts (e.g., Charles M. Curley) and art combinations. They are not on this patent, but they map the same specification lineage and give you a template for the prior-art landscape and expert framing. Access via PTAB E2E at https://ptacts.uspto.gov/ptabweb/ or the USPTO PTAB Decisions page at https://www.uspto.gov/patents/ptab/decisions.
3. Mind the family-and-continuation trap. US 8,113,618 (continuation of the '498, filed 2010-10-22, issued 2012-02-14, and also asserted against HP) is an un-adjudicated twin. If Slingshot asserts the '498 against you, expect the '618 to follow; any invalidity theory should be built once and mapped across both, and you should verify whether the '618 has its own litigation or PTAB history before finalizing a joint defense.
4. If you intend to petition, move on the § 315(b) clock deliberately and budget for a real fight. With all 15 claims live and no prior institution to piggyback on, you are asking the Board to do first-instance work on claim 1's "total number of ink tanks" limitation. That is the limitation to attack — the specification itself (paras. on configuration identifiers such as "4 on the first memory tag represents that there are a total of four ink tanks installed") supplies the intrinsic record you'll have to work around.
5. If you are HP (or in privity with HP), prioritize the non-PTAB defenses. The 2021-04-01 dismissal with prejudice of the W.D. Tex. action as to the asserted patents — including the '498 — is likely a stronger and cheaper defense than an IPR, and IPR estoppel does not run in your favor here because no IPR on this patent was ever instituted. Confirm the dismissal order's scope and preclusive effect before filing anything at the Board.
6. Standing caveat on this memo's central finding. Before you file, run a live party-name PTAB E2E search for "Slingshot Printing LLC" filtered to patent 7,819,498 and confirm the ODP result directly. I found no proceedings, but the absence of a hit is a negative search result, not an affirmative record of non-filing, and I would not stake a filing position on it without that one confirmation step.

I'll pull the assignment-record evidence for this patent from public sources before writing the chain.

Good leads on reel numbers. Let me pin the specific reels/frames tied to the '498 patent.

Confirmed the Lexmark→Funai reel. Now let me find the Funai→Slingshot reel and the inventor→Lexmark record.

Assignment & Ownership Analysis — US 7,819,498 B2

Method / evidence caveat (read first): I do not have a live, authenticated USPTO Assignment Center session. The USPTO Assignment Search UI (assignmentcenter.uspto.gov) is a JavaScript application that does not expose machine-readable record text to a crawler, and my attempt to retrieve per-patent reel/frame data for this specific number returned no documents. What follows distinguishes (a) reel/frame data I confirmed from third-party chain-of-title papers and Espacenet/INPADOC records, (b) reel/frame data I found for sibling Lexmark patents that I believe but cannot prove covers the '498, and (c) fields I could not confirm at all (notably the correspondent of record for every link). I have not invented any reel, frame, attorney name, or address.

Framing contradiction to flag: the previously generated summary states your prompt gave the current date as April 26, 2026, whereas this prompt states 2026-09-30. I treat 2026-09-30 as current. This matters only in that the prior section's CAFC findings (May/July 2026 opinions) are no longer "post-dated" — they are now in the past and consistent.

Inventors

Unusual-pattern check:

• Only one inventor, so the "all inventors departed within 12 months" heuristic cannot produce a signal from headcount alone.
• I found no evidence of McReynolds departing Lexmark near filing. I did not recover an employment-end date, so I mark this unclear, leaning not-present. Do not treat the absence as exculpatory — it is an absence of data, not a finding.
• One genuine oddity worth recording: Google Patents' "Cited By" table lists US 2011/0032290 A1 (the child continuation publication) with the assignee field rendered as "Mcreynolds Jason Todd" rather than Lexmark. That is almost certainly a bibliographic artifact of the pre-grant publication (published 2011-02-10 before the recordation of the intervening transfers was reflected in the publication database), not a real re-assignment back to the inventor. Flagging it because a naive scraper would read it as a genuine inventor-owned link. Low confidence in the explanation; high confidence the record itself is anomalous.

Original assignee

Lexmark International, Inc. (named on the face of the issued patent; Delphi/Jefferson-smart, formed 1991 as an IBM divestiture per Slingshot's own complaints).

• Did they ship a product embodying the claims? Yes, unambiguously. The patent is directed to ink tank memory tags (RFID / contact memory) on tank-style printheads, and Lexmark was a first-tier inkjet OEM. Slingshot's Waco complaint expressly pleads Lexmark's R&D history and printer/ink-cartridge business, and the specification itself is written from Lexmark's own product context (CMYK/CMY tank configurations on on-carriage printheads). Claims 1 and 10 read on a physical ink tank, a physical reservoir, and a physical memory tag — this is a product patent, not a paper patent.
• Primary line of business: enterprise imaging/printing hardware and supplies; inkjet was a core line until the 2013 exit.
• Current status: operating, but no longer in the inkjet business at all. Lexmark exited inkjet in 2013, selling the inkjet technology, ~1,500 worldwide inkjet patents, and its Philippines inkjet manufacturing subsidiary to Funai Electric Co., Ltd. for ~US$100 million (announced April 2013; Funai's own notice of acquisition; ITPro coverage). Lexmark was later taken private (2016, Ninestar/Apex-led consortium). Critically for the NPE analysis: the original assignee never asserted this patent, and by 2019 it had no inkjet product or competitor relationship to protect with it.

Assignment timeline

Four recorded link-types are relevant. Only one reel/frame is confirmed at the "confirmed" confidence level; one is confirmed for the conveyor generally but not for this patent individually; two are unconfirmed.

1. Inventor → Lexmark International, Inc.

• 2007-12-19 (executed) / recorded 2007-12-19 — Reel not recovered (unconfirmed)
  • Conveyance: Assignment of assignor's interest
  • Assignor: Jason Todd McReynolds
  • Assignee: Lexmark International, Inc., 740 West New Circle Road, Lexington, KY
  • Correspondent: not recovered — I will not guess. (For context only, and not a finding about this patent: the recordation notice for a different, contemporary Lexmark application, reel 014287/0489, lists Lexmark's in-house correspondent as Scott N. Barker, 740 W. New Circle Rd., Lexington, KY 40550. Whether Barker handled the '498 recording is unverified.)
  • Context: Standard employee invention assignment / internal capture, executed at filing.

2. Lexmark → Funai Electric Co., Ltd. (portfolio divestiture)

• 2013-04-01 (effective, U.S. E.S.T.) / recorded 2013-05-14 — Reel 030416 / 0001
  • Conveyance: Assignment (carved out of the "Intellectual Property Assignment and License Agreement, dated April 2, 2013 JST / April 1, 2013 EST")
  • Assignors: Lexmark International, Inc. and Lexmark International Technology, S.A. (note the second assignor — a Luxembourg/Swiss Lexmark IP-holding affiliate; the portfolio was not held purely by the U.S. operating company)
  • Assignee: Funai Electric Co., Ltd., Daito, Osaka, Japan
  • Correspondent: not recovered.
  • Context: Strategic divestiture / exit from a business line. Not a bankruptcy sale. Lexmark was exiting inkjet and sold 1,000+ U.S. assets to its long-time OEM contract manufacturer.
  • Confidence flag: Reel 030416/0001 is confirmed via multiple independent third-party chain-of-title statements on other Lexmark inkjet patents (US 7,410,246 and US 7,410,246-family papers; Espacenet INPADOC events for US 2005/285898 and US 2005/207816) reporting LEXMARK INTERNATIONAL, INC.; LEXMARK INTERNATIONAL TECHNOLOGY, S.A.; REEL/FRAME:030416/0001 with new owner FUNAI ELECTRIC CO., LTD effective 20130401. The '498 is a Lexmark inkjet patent of exactly this vintage, and Slingshot's pleadings describe the same transaction as covering the patents-in-suit. I infer, but did not directly verify, that the '498 is one of the assets conveyed at reel 030416/0001.

3. Funai → Slingshot Printing LLC (transfer to a licensing-only entity)

• 2019 (executed) / recorded: Google Patents shows 2019-03-29 — Reel 051430 / 0989 (probable, NOT confirmed for this patent)
  • Conveyance: Assignment
  • Assignor: Funai Electric Co., Ltd.
  • Assignee: Slingshot Printing LLC, a Delaware LLC, principal place of business 10015 Old Columbia Road, Suite B215, Columbia, Maryland 21046
  • Correspondent: not recovered. This is the single most important missing field in the chain and I am explicitly declining to fill it by inference.
  • Context: Transfer-to-asserter. Contemporaneous trade coverage (The Recycler) states that in April 2019 Funai assigned "all substantial rights, title and interest" to Slingshot; Slingshot's own complaints state Funai "subsequently assigned to Slingshot all rights, title, and interest in the Patents in Suit," and that "Slingshot is in the business of licensing patented technology."
  • Confidence flag: Reel 051430/0989 appears in a Slingshot §3.73(b) statement of record as the cited recordation for its acquisition from Funai — but I located it in the papers of IPR2023-00313, which concerns US 7,484,823, a different patent. It is therefore evidence that Funai→Slingshot was recorded in bulk (consistent with a single reel covering many Lexmark-origin assets), not evidence that 051430/0989 is the '498's recording. Treat the '498's Funai→Slingshot reel/frame as unconfirmed.

4. No subsequent assignment

• No assignment out of Slingshot Printing LLC was found. The chain terminates in an active litigant. Slingshot was the plaintiff in the 2019 HP actions and the 2022 Canon actions and remains the named Patent Owner in the IPRs through at least 2023–2024. The continuation US 8,113,618 B2 (from application 12/909,912, filed 2010-10-22) is a separate family asset with its own record but traveled the same Lexmark→Funai→Slingshot route.
• If the Assignment Center returns no additional records beyond the above four links, that is itself the finding: the patent is still held by the asserting NPE, unencumbered and unrecorded-out.

Timeline diagram

timeline
    title Ownership of US 7819498
    2007 : Filed by Lexmark International
         : Inventor McReynolds assigns to Lexmark
    2010 : Patent issued on 2010-10-26
    2013 : Lexmark inkjet portfolio sold to Funai
    2019 : Funai assigns to Slingshot Printing LLC
         : First HP suits filed in June
    2022 : Slingshot asserts family against Canon
    2024 : Slingshot still defending IPRs

NPE / troll-pattern signals

1. Shell-entity transfer — PRESENT.
The patent moved from Funai Electric, an operating manufacturer (it built inkjet hardware for Lexmark since 1997, took over the former Lexmark Philippines cartridge plant, and later produced Kodak-branded printers), to Slingshot Printing LLC, a Delaware LLC that describes itself in a filed federal complaint as being "in the business of licensing patented technology" with no product allegation anywhere in the chain (Slingshot Printing LLC v. Canon U.S.A., Inc., E.D.N.Y. 2:22-cv-01852, Complaint ¶2). Support: reel 030416/0001 (2013-05-14) then the 2019 Funai→Slingshot record, Google Patents legal event 2019-03-29. Note the discipline here: the finding rests on the licensing-only business model admitted in a pleading, not on the "LLC" suffix, which by itself proves nothing.

2. Known asserter in the chain — PRESENT.
Slingshot Printing LLC is a documented high-frequency plaintiff, not a one-off:

• June 11, 2019 — three complaints against HP Inc. in W.D. Tex. (Waco), 6:19-cv-00362 / -00363 / -00364; Google Patents' family record links the '498 to 6:19-cv-00364. The assertion list includes the '498 and its continuation '618.
• January 7, 2022 — Slingshot Printing LLC v. Canon U.S.A., Inc. et al., 2:22-cv-00123 (E.D.N.Y.), followed by 2:22-cv-01852.
• Repeated PTAB exposure: HP IPRs IPR2020-01084 / -01085 / -01086 / -01090; Canon IPRs IPR2022-01416, -01541, IPR2023-00309, -00312, -00313.
• RPX reported a related vehicle, Slingshot Technologies LLC, acquiring 20+ US assets from Intellectual Ventures (assignments late 2018/early 2019) — i.e., a named-IV-divestiture-adjacent family. This is the one place in the record where an Intellectual Ventures touchpoint appears; keep the two Slingshot entities distinct absent common-principal proof.

3. Repeat correspondent across the chain — UNCLEAR / NOT ESTABLISHED.
I could not recover the correspondent of record for any link on this patent — not for the 2007 McReynolds→Lexmark recording, not for reel 030416/0001, and not for the Funai→Slingshot recording. I therefore cannot report the single most probative tell in the brief (a recurring attorney or recording firm binding nominally unrelated assignees). I will not substitute a name for a record I did not read. Recommended next step, in priority order: pull reel 030416/0001 and the 2019 Funai→Slingshot record for this patent from Assignment Center and capture the correspondent block verbatim, then test it against the correspondents on sibling '618, '523, '823, and '864 records for recurrence.

4. Cascading transfers — NOT PRESENT (in the classic <24-month sense), with a caveat.
The chain is long-dwell, not cascade-fast: 2007-12-19 → recorded 2013-05-14 (≈5.4 years) → recorded 2019-03-29 (≈5.9 years). There is no run of chained LLCs sharing a correspondent address within 24 months. The relevant compression is confined to the final hop, and that is captured as signal 5 below rather than double-counted here.

5. Pre-litigation transfer — PRESENT (strong).
Funai→Slingshot was recorded 2019-03-29 (Google Patents legal event); the first infringement suits asserting the '498 family were filed 2019-06-11. That is roughly 10 weeks — comfortably inside a 6-month window, and exactly the pattern the signal is designed to catch: title is cleaned up immediately before assertion so that standing, damages reach-back, and venue are all in order at filing. This is the strongest single signal on this record because it is date-arithmetic between two independently documented events, not inference.

6. Bankruptcy fire-sale — NOT PRESENT for the original assignee; UNCLEAR for the intermediate.
Lexmark did not go bankrupt and did not sell the inkjet portfolio in insolvency — the 2013 sale was a deliberate strategic exit from the inkjet market (~1,700 jobs cut, $95M/yr savings projected from 2015), negotiated with its own OEM partner for ~$100M. I found no Chapter 7/11 proceeding producing this asset. Flagged lead, unverified: I have a recollection that Funai Electric later entered insolvency proceedings in Japan, but I could not confirm it within my search budget and I will not assert it as fact. If true it is not legally relevant to the 2019 transfer (which preceded it) but is relevant to whether any later chain-of-title cloud or trustee interest exists. Verify before relying on it.

7. Privateering — PRESENT (functional form).
Lexmark, an operating company, divested the inkjet portfolio to its own OEM supplier rather than asserting it; Funai then conveyed it to a licensing-only LLC; that LLC immediately sued HP (2019) and Canon (2022) — Lexmark's direct former competitors in inkjet printing. The classic privateering vignette is "operating co. → NPE → NPE sues operating co.'s rivals." Here the intermediate (Funai) is itself operating, so the strict form is modified, but the functional effect is identical and the pleading record (Slingshot's complaints describing the Lexmark→Funai→Slingshot chain as the source of the asserted rights) documents it. One honest qualifier: because Lexmark had exited inkjet by 2013, there was no ongoing competitive position being shielded — so read this as divestiture-to-asserter with a privateering-like structure rather than a smoking-gun competitive-suppression scheme.

8. Defensive aggregator (anti-NPE) — NOT PRESENT.
The chain terminates at Slingshot Printing LLC, an active plaintiff. There is no RPX / AST / LOT / OIN / Unified Patents link anywhere in the record. Notably, Unified Patents appears in this file only as a litigation-data source (its portal hosts the 6:19-cv-00364 record) — that is a database vendor, not an assignee. Do not misread the citation as a defensive-aggregation signal. The inverse conclusion holds: this patent has not been neutralized.

Verdict

NPE — high confidence.

Justification: Two independent strong signals and a third corroborating one, each anchored to dated records rather than naming. First, known asserter: the current assignee, Slingshot Printing LLC, is a serial filer with at least three 2019 W.D. Tex. complaints against HP (incl. 6:19-cv-00364, the case Google Patents links to this family) and two 2022 E.D.N.Y. actions against Canon, and has been the Patent Owner in ten-plus IPRs. Second, pre-litigation transfer: title passed Funai→Slingshot on or about 2019-03-29 and the first suits followed on 2019-06-11, roughly 10 weeks later. Third, shell/licensing-only transfer: the '498 went from product-shipping Lexmark (via reel 030416/0001 recorded 2013-05-14) to Funai, and then to a Delaware LLC that states on the record in a federal complaint that it is "in the business of licensing patented technology" — with the original assignee, by then out of the inkjet market entirely, never having asserted it. The cascading-transfer and defensive-aggregator signals are absent, and bankruptcy is absent for the original assignee, which is why this is not a "troll-divestiture" story but a straightforward corporate-exit → NPE chain.

Residual uncertainty that would move the verdict if resolved adversely: I could not confirm (i) that the '498 is individually within reel 030416/0001, or (ii) the '498's Funai→Slingshot reel/frame and correspondent. If the correspondent on the 2019 recording turns out to be a repeat-player attorney appearing across the sibling '618, '523, '823, and '864 reels, this strengthens to a textbook repeat-counsel NPE finding and would also support a cascading-transfer call for the Slingshot/Slingshot Technologies family. If instead the 2019 recording shows an operating-entity assignee with products, the verdict would need revisiting — but nothing in the retrieved record supports that.

Verify at: USPTO Assignment Center — https://assignmentcenter.uspto.gov/ (legacy mirror: https://assignment.uspto.gov/patent/index.html). Search by patent number 7819498; also search the family members 8113618 and applications 11/959,593 and 12/909,912. Capture the correspondent block for each hit — that is the field this analysis most needs and could not obtain. Case dockets for corroboration: https://portal.unifiedpatents.com/litigation/Texas%20Western%20District%20Court/case/6%3A19-cv-00364.

I'll verify the cited references for US 7,819,498 against the authoritative text and check details on each cited patent.

Let me get details on the remaining cited references.

Prior-Art Analysis — US 7,819,498 B2

Scope note / cross-reference: This builds on the earlier bibliographic and litigation sections (which already established the citation count, claim structure, assignee chain, and the Slingshot v. HP / Canon / PTAB / CAFC history). I do not repeat those. Date flag (carried forward and extended): the prior section flagged that the prompt's "April 26, 2026" conflicted with post-April-2026 search material; my environment clock now reads 2026-09-30. I treat the patent text as authoritative for content and note that all substantive statements below are grounded in the patent's own front page and the cited references' own publications, not in the docket timeline.

1. What the record actually shows for the citation list

The authoritative patent PDF (front page, "References Cited") lists eight U.S. patent documents, all marked "cited by examiner," and no foreign patent documents or non-patent literature:

Source for the printed list: US 7,819,498 front page at https://patentimages.storage.googleapis.com/77/6c/aa/84d00f31b4599d/US7819498.pdf, corroborated by the Google Patents "Citations (8)" table (https://patents.google.com/patent/US7819498/en). The examiner-cited sub-entries 5–7 carry the "347/19" class notation, confirming the art was searched in the printer "detecting/testing" subclass.

No contradicting record found: no additional citation appears in the authoritative text beyond these eight. I therefore did not substitute any "similar number" reference; all eight are the exact numbers printed on the '498 front page.

2. Legal framework applied (watch this — it is pre-AIA)

US 7,819,498 was filed 2007-12-19, so pre-AIA 35 U.S.C. § 102 governs. Applicable pre-AIA paragraphs here:

• § 102(b): printed publication/patent more than one year before 2007-12-19 (i.e., before 2006-12-19).
• § 102(a)/§ 102(e): patents or published applications dated before the filing date (the "critical date" question is immaterial here because all eight references predate the filing).

Anticipation standard: a reference anticipates a claim only if it discloses every element, arranged as in the claim, in a single reference. The governing limitation of the two independent claims (1 and 10) is that the tank's memory holds ink tank configuration instructions that identify the total number of ink tanks installed in the printing system when the tank is one of the installed tanks. That is the point of novelty the specification stresses (the "otherwise the printer is unaware" passage).

3. Reference-by-reference review

REF 1 — US 6,155,664 A ("Off-carrier inkjet print supply with memory")

• Citation/date: US 6,155,664 A, granted 2000-12-05; app. 09/100,042 filed 1998-06-19; Lexmark International, Inc.; inventor William Paul Cook. PCT counterpart WO 99/65695.
• Disclosure: Off-carrier (remote) ink cartridge carries a memory storing "second information related to characteristics" of the remote cartridge; the printhead cartridge carries a memory storing "first information"; the printer controller accesses both, compares them, and generates control signals based on compatibility. Also stores ink-level/drop-count values.
• § 102 status: § 102(b) art.
• Potential anticipation: None of claims 1–15. It discloses a memory tag on an ink supply read by a controller (germane to the substrate of claim 1 and to claim 9's memory-tag concept), but it compares two components' characteristic data; it never stores, on a tank, an identifier of the total number of installed tanks, nor does it gate/terminate memory operations on that basis. At most it is § 103 art for the "memory tag on the tank" element.

REF 2 — US 6,158,850 A ("On carrier secondary ink tank with memory and flow control means")

• Citation/date: US 6,158,850 A, granted 2000-12-12; app. 09/100,484 filed 1998-06-19; Lexmark; inventor William Paul Cook. PCT counterpart WO 99/65698.
• Disclosure: Base cartridge assembly memory + secondary on-carrier ink tank memory store compatibility/identification information; printer electronics read both and, on a match, enable a flow-control device. Notably, an identification code identifies each secondary tank as belonging to a "set" of secondary tanks (claims 1, 3, 13).
• § 102 status: § 102(b) art.
• Potential anticipation: The "set identification code" is the closest thing in the list to a "configuration identifier," but it is a set-membership code, not a total-count of installed tanks. No anticipation of claims 1/10 or dependents; possible § 103 art for the "ink tank configuration instruction" concept (claim 11).

REF 3 — US 6,302,527 B1 ("Method and apparatus for transferring information between a printer portion and a replaceable printing component")

• Citation/date: US 6,302,527 B1, granted 2001-10-16; app. 09/415,331, filed 1999-10-07/08 (CIP of 09/295,080), priority 1999-04-20; Hewlett-Packard Company; inventor Ray A. Walker.
• Disclosure: A replaceable printing component (ink reservoir) is provided with a wireless (RF) link that broadcasts sensor/status information (e.g., ink level) to a receiver in the printer portion.
• § 102 status: § 102(b) art.
• Potential anticipation: None of claims 1–15. It is the best single reference in the list for the wireless/RF memory-tag link used in dependent claim 9, but claim 9 incorporates all of claim 1, and the "total number of installed tanks" limitation is absent. So no anticipation; strong § 103 art for the RFID/wireless transfer element.

REF 4 — US 6,672,695 B1 ("Ink cartridge management system, printer, and ink cartridge")

• Citation/date: US 6,672,695 B1, granted 2004-01-06; app. 09/653,346 filed 2000-08-31; priority JP P11-245388 (1999-08-31) et al.; Seiko Epson Corporation; Naka, Tojyo, Saruta, Shinada.
• Disclosure: Each ink cartridge has a first storage system holding ink-consumption data and identification of the respective cartridge; the printer has a second storage system holding backup data of "one or ones of the ink cartridges which have ever been mounted to the printer"; a CPU compares stored data to compute consumption.
• § 102 status: § 102(b) art.
• Potential anticipation: This is the most conceptually relevant of the eight — it shows per-cartridge identification data plus printer-side tracking of which cartridges are/have been mounted. But the claim-1 requirement is data on the tank's memory identifying the total number of tanks installed; '695 puts the "which cartridges exist" intelligence in the printer's second storage, in service of consumption accounting, not read-termination of memory operations. No anticipation; excellent § 103 art.

REF 5 — US 6,935,716 B2 ("Recording liquid container and ink jet recording apparatus")

• Citation/date: US 6,935,716 B2, granted 2005-08-30; app. filed 2002-04-10 (priority JP 2001-111538, 2001-04-10); Canon Kabushiki Kaisha; Hatasa et al.; classified 347/19.
• Disclosure (verified only at the level of title/classification/assignee — see uncertainties): A recording-liquid container (ink tank) provided with a storage element, in an ink jet recording apparatus that reads information from the container and performs a detection/determination function (347/19).
• § 102 status: § 102(b) art.
• Potential anticipation: None apparent. Nothing in the available record shows this reference storing a total number of installed tanks on the container. I could not retrieve the full text within my search budget, so I rate this "no anticipation found," not "none exists" (§ 103 relevance to the "memory on the container" element only).

REF 6 — US 6,938,976 B2 ("Printer and method therefor adapted to sense data uniquely associated with a consumable loaded into the printer")

• Citation/date: US 6,938,976 B2, granted 2005-09-06; Eastman Kodak Company; Siwinski et al.; classified 347/19.
• Disclosure (title-level): The printer senses data uniquely associated with a consumable (e.g., an ink/printing consumable) loaded into it — i.e., reading identifying data from the consumable.
• § 102 status: § 102(b) art.
• Potential anticipation: None apparent. "Data uniquely associated with a consumable" is a single-component identifier; the claim requires data identifying the total number of installed tanks when the tank is one of the installed tanks. No anticipation; § 103 art for the "tank carries data the printer reads" element.

REF 7 — US 7,137,684 B2 ("Inkjet printer having arbitrarily mounted cartridge and method of recognizing the cartridge")

• Citation/date: US 7,137,684 B2, granted 2006-11-21; app. 11/403,804 filed 2006-04-14 (continuation), priority KR 2001-10-31; Samsung Electronics Co., Ltd.; Kim and Ju; published sibling pre-grant US 2003/0081062 A1 (2003-05-01); classified 347/19.
• Disclosure: Two carriers accept first/second cartridges arbitrarily mounted in either carrier; a print head detecting portion detects the presence of cartridges in each carrier; a print head ID recognizing portion recognizes whether each mounted cartridge is a black or color cartridge; the printer then defines the position of each enabled cartridge and informs the external apparatus.
• § 102 status: § 102(b) via the 2003-05-01 pre-grant publication; also § 102(e) as a U.S. patent.
• Potential anticipation: Closest of the eight to the "determine the installed-tank configuration" concept — it detects which cartridges are mounted, recognizes their identity/type, and locates them by carrier. However, the configuration intelligence resides in the printer's detection/ID-recognition circuitry, and the reference does not disclose storing on a cartridge's memory an identifier of the total number of installed tanks, nor terminating/continuing printer memory operations responsive to such stored data. No literal anticipation of claims 1/10; it is the primary § 103 reference for the "detect configuration" idea and for dependent claim 8 (location of another tank).

REF 8 — US 7,212,637 B2 ("Cartridge validation with radio frequency identification")

• Citation/date: US 7,212,637 B2, granted 2007-05-01; filed 2003-03-11; Rimage Corporation; inventor Salisbury.
• Disclosure: RFID-based validation of a cartridge — an RFID tag on the cartridge is read by the apparatus to validate/authenticate the cartridge.
• § 102 status: granted 2007-05-01, i.e., within one year of the 2007-12-19 filing → § 102(a) and § 102(e) (U.S. patent, filed 2003-03-11), not § 102(b) on the grant date (an earlier pre-grant publication, if any, would supply § 102(b) — not confirmed).
• Potential anticipation: None of claims 1–15. It reinforces the RFID-tag element of claim 9, but claim 9 depends from claim 1 and the total-count limitation is absent.

4. Bottom line on § 102

No one of the eight examiner-cited references anticipates any of claims 1–15, in whole or in part, under pre-AIA § 102. Specifically:

• Claims 1 and 10 (independent): each requires an on-tank memory storing ink tank configuration instructions that identify the total number of ink tanks installed. The references disclose (a) memories on ink supplies (Refs 1, 2, 3, 4, 5, 6, 7, 8), (b) characteristic/compatibility or identification data (Refs 1, 2, 4, 6, 8), (c) wireless/RFID tag links (Refs 3, 8), and (d) detection of which cartridges are present and where (Ref 7). None stores or reads a "total number of installed tanks" from a tank's own memory to drive whether further memory operations occur.
• Dependent claims: the near-misses map as follows — claim 8 (identify the location of at least one other tank) ↔ Ref 7 (position determination); claim 9 (RFID tag) ↔ Refs 3 and 8; claim 11 (configuration identifier and/or location identifier) ↔ Ref 2's set-identification code and Ref 7's ID/position recognition. Each of these claims, however, inherits the claim-1 total-count limitation, so none is literally anticipated.

Most relevant prior art, ranked: (1) US 7,137,684 (Samsung — recognizes/positions mounted cartridges); (2) US 6,672,695 (Epson — per-cartridge ID + printer-side history of mounted cartridges); (3) US 6,302,527 (HP — wireless ink-supply data link); (4) US 7,212,637 (Rimage — RFID cartridge validation). These four are the natural § 103 combination set opposing counsel would assemble against claims 1/10; refs 1, 2, 5, 6 supply secondary elements (memory-bearing tanks, compatibility data, consumable-data sensing).

Why the examiner still allowed the case: the allowance turns on the "total number of ink tanks installed" limitation being stored on the tank and used by the controller to continue/terminate memory operations — a limitation that the eight cited references, singly or as the examiner read them, did not teach.

5. Stated uncertainties (be explicit rather than overclaim)

1. Full text of Refs 5 and 6 (US 6,935,716 and US 6,938,976) could not be retrieved within my search budget. Their characterizations above rest on title, assignee, priority, and 347/19 classification. Treat the "no anticipation" findings for those two as "none found," not "none exists."
2. § 102(e)/(b) date granularity: I determined § 102(b) vs. § 102(a) from the grant dates and the one reference's confirmed pre-grant publication (US 2003/0081062, 2003-05-01). I did not verify every reference's earliest pre-grant publication or the exact earliest U.S. filing date in each § 102(e) chain (relevant chiefly to Ref 8, filed 2003-03-11).
3. No non-patent literature appears in the authoritative Google Patents "Citations (8)" table; if the USPTO's own file wrapper (PTO-892/1449) contains NPL not reproduced by Google Patents, my list would be incomplete.
4. Contradiction carried forward, not resolved: the prior summary noted the prompt's "April 26, 2026" versus post-April-2026 search results; my clock now reads 2026-09-30. This does not affect the prior-art analysis (all references were published 2000–2007), but it means any new 2026 litigation/PTAB material referenced elsewhere should be re-checked for a later cutoff.
5. No post-filing family members are prior art: the continuation US 8,113,618 B2 / US 2011/0032290 A1, the "Cited By" documents (US 2015/0165778 A1, US 9,555,634 B2), and the "Families Citing" members (US 9,132,656, US 9,108,423, JP 6237005) all post-date the '498 filing and/or share its priority; they are not § 102 art against the '498 claims. I flag this only because they appear in the record and could be mistaken for prior art.

I'll verify the cited prior art and look for additional references bearing on obviousness. Note upfront a date inconsistency I must flag: the system header says today is 2026-09-30, while your task prompt says April 26, 2026. This matches the discrepancy flagged in the earlier section (which also noted a "2029-04-26 adjusted expiration"). I'll proceed treating the analysis as of the later of the two dates, which only matters for what counts as prior art and for post-issuance events.

Now let me check the remaining cited references and hunt for additional prior art on the "memory stores the number/configuration of installed cartridges" concept.

Obviousness Analysis — US 7,819,498 under 35 U.S.C. § 103

Scope note on dates. Your task prompt states the current date is April 26, 2026, but the session header says 2026-09-30, and the prior section already flagged a date inconsistency (it found CAFC material dated May and July 2026). None of that changes the §103 analysis, because the only date that matters is the critical date. I treat the analysis as current as of the later date. I also note that the full-text dump supplied for this patent contains apparent OCR artifacts (e.g., "BRIEF SUMMARY OF TIDE INVENTION," "ELPROM" for EEPROM, "CMSK"); per the strict rule I have not silently corrected serial numbers or identifiers, but I flag these as transcription artifacts rather than substantive claim terms.

1. Framework, critical date, and level of ordinary skill

Critical date: December 19, 2007 (filing date = priority date; the '498 is not a continuation of anything earlier — its only family member, US 12/909,912 → US 8,113,618, is a later-filed child, so it is not prior art). Prior art therefore includes anything publicly available before 2007-12-19, plus §102(a)(2)/(e) filings.

Claims in issue: independent claims 1 (apparatus: ink tank) and 10 (method). Dependent claims 2–9 and 11–15.

Level of ordinary skill (proposed): a bachelor's degree in electrical/computer engineering, mechanical engineering, or computer science, or equivalent, plus 2–4 years of experience in inkjet printer firmware and consumable/printhead electronics — or a relevant master's degree with less experience. This is an unusually small step above the routine implementer, which matters: a low level of skill cuts toward obviousness for a limitation that is merely the content of a data field.

Governing law: Graham v. John Deere, 383 U.S. 1 (1966); KSR Int'l v. Teleflex, 550 U.S. 398 (2007). Under KSR, the motivation to combine need not appear in the references themselves; it may come from the problem the inventor was addressing and from ordinary creativity. Critically, KSR holds that designing around a known problem with known elements is obvious, and that "if a technique has been used to improve one device, and a person of ordinary skill in the art would recognize that it would improve similar devices in the same way, using the technique is obvious."

Two doctrinal overlays I flag up front, because they cut in opposite directions:

1. Printed-matter / data-content doctrine. The sole point of novelty in claim 1 is what is stored in the memory tag. A limitation directed to informational content is given patentable weight for §103 purposes only where the content bears a functional relationship to the physical substrate (In re Gulack, 703 F.2d 1381 (Fed. Cir. 1983)). For claim 1 alone, no functional consequence is recited — the claim stops at "the ink tank configuration instructions identifying a total number of ink tanks." That is a real vulnerability: an examiner could argue the data content is non-functional printed matter and that the claim collapses onto the prior art's generic "memory tag on an ink tank." Conversely, In re Lowry, 32 F.3d 1579 (Fed. Cir. 1994) supports giving weight to a specific data organization in memory where it dictates how the memory is addressed/used. The dependent claims (3–8, 10, 12–15) clearly recite functional consequences, so they preserve the limitation's weight — a classic claim-differentiation problem for the patentee.
2. The patent's own background is an admission. The specification expressly describes the prior-art procedure (carriage indexes to each possible default tank position, ~500 ms per read/write, ~2 s total for a four-tank default) and expressly states the motivation for the invention: "avoiding attempting unnecessary memory operations may reduce the overall time required to perform all of the memory operations, and thus may reduce the negative impact performing memory operations has on printing speeds." Under KSR and MPEP 2141–2144, an applicant's own admission of a known problem is fair game as evidence of the "motivation" prong.

2. The cited prior art (the "Prior Art" set on this page)

All eight references are in B41J 2/175 or an adjacent consumable-identification class → analogous art, and several are from the same three companies (Lexmark, HP, Seiko Epson) that dominated this space, which makes them highly combinable with each other.

Additional analogous art surfaced during verification (not on the face of the '498) — useful because it supplies the data-content and multi-component teachings the eight cited references lack:

• US 5,699,091 / EP 0 789 322 (Bullock et al., HP, "Replaceable part with integral memory for usage, calibration and other data"): a replaceable cartridge with a serial-access memory whose data includes "parameters for controlling operation of the apparatus." This is the canonical teaching that consumable memory stores data that configures the printer, not merely data about the part. EP 0789322 A3 PDF
• US 5,812,156 (Bullock et al.) — memory IC integrated into an ink cartridge/printhead storing "ink type, manufacture date and batch, and performance" (as characterized in the 6,938,976 specification).
• US 5,365,312 (Hillman et al.) — "memory associated with an ink reservoir for an inkjet printer" (same source).
• US 5,049,898 (Arthur et al., HP) — "Printhead having memory element."
• WO 97/28001 — industrial printer receiving "at least one consumable cartridge," each with an electronic label, communicating by electromagnetic link. WO 98/52762 (Purcell et al., Encad) — "memory circuits … disposed within ink and paper consumables, including memory connected with an RF transponder." (Both characterized in EP 1 060 895 B1.)
• US 6,739,689 B2 (Samsung, "Ink cartridge identifying apparatus") — distinguishes mono / color / photo cartridges by contact-node patterns; relevant to type identification (not count).
• US 6,676,240 B2 (HP) — an RF linking device mounted to the marking engine housing that requires docking "so that there is substantially no relative movement" relative to the printer's RF linking device — directly relevant to alignment-based reading, and thus to claims 8 and 15. PDF

3. Claim 1 — element-by-element

Bottom line on claim 1: A §103 rejection is constructible but is not a clean two-reference show. It requires (a) a primary reference for the tagged ink tank with a data-bearing memory, (b) a secondary reference for the printer needing/determining its installed-tank configuration, and (c) a KSR-style reasoning bridge to convert "the tank says what it is" into "the tank says how many there are."

4. Claim 10 — element-by-element

Claim 10 is meaningfully stronger than claim 1 for patentability purposes (it recites the functional consequence, so the printed-matter objection evaporates), but it is also meaningfully closer to the prior art of multi-tag polling (6,938,976; 6,155,664).

5. Proposed §103 combinations and the motivation statements

Combination A (strongest apparatus rejection) — 6,155,664 as primary, in view of 7,137,684, further in view of 6,302,527

Primary — US 6,155,664. Discloses an ink tank (remote ink cartridge) with a reservoir and a memory device disposed on it, whose stored data the printer controller reads and uses to characterize the overall printing system: "the printer controller … compares the first information to the second information … determines the compatibility of the printhead cartridge and the remote ink cartridge, and generates control signals according to the compatibility." This is a consumable-memory-drives-system-configuration teaching, from the same assignee's field and the same class.

Secondary — US 7,137,684. Supplies the missing functional concept: a multi-tank inkjet printer whose cartridges are interchangeable and arbitrarily mounted, where the printer must detect existence, recognize identity, and define position for each cartridge, and which operates in one of four enumerated mounting configurations (Table 1: black+black, black+color, color+black, color+color). It expressly recites a memory on the cartridge storing the print-head ID.

Tertiary — US 6,302,527 (and/or 6,938,976, 7,212,637) for the RF/wireless link if claim 9 is reached.

Motivation to combine (KSR-compliant): (i) Both references are in the same field and the same class, addressing the same problem — a printer that must adapt to whatever interchangeable supplies the user installs. (ii) 7,137,684 makes the number of installed components a variable that changes printer behavior (two black cartridges vs. black+color changes image generation and enables doubled throughput at normal resolution); once the printer's mode depends on which and how many tanks are present, encoding that fact where the printer must look anyway — the tank's memory — is an obvious design choice. (iii) The '498's own background identifies the known problem of the printer being "unaware that there are no other ink tanks," which is precisely the "detecting existence" concern of 7,137,684.

Result: every element is present or would have been obvious; the only residual question is whether "identifying a total number" rather than "identifying this tank" is a patentable difference.

Combination B (strongest method rejection) — 6,938,976 as primary, in view of 7,137,684

Primary — US 6,938,976. Claim 2/3 teach first and second transponders, each with a memory, and a transceiver adapted to alternately communicate with them; the abstract teaches that memory data lets the printer's control logic "determine the type of consumable that is loaded." This is a printer that performs a sequence of memory operations across multiple consumables — precisely the loop the '498 is trying to truncate.

Secondary — US 7,137,684, for the printer needing its tank configuration and defining cartridge positions, plus 6,155,664 for consumable memory that characterizes the system.

Motivation: Given 6,938,976's alternate polling of N transponders, a POSITA seeking to shorten the read sequence has the known incentive to know the loop bound before entering the loop. Storing the bound (an integer N, or a "single/dual/N" mode code) in the memory of the tag that is read first is the most natural implementation, and the patent itself concedes the aim is print-speed improvement.

Combination C (claim 9 / RFID element) — 6,302,527 + 6,938,976 + 7,212,637

Claim 9 ("the memory tag is a radio frequency identification memory tag that communicates with a memory tag reader via a radio frequency communications protocol") is strongly obvious — effectively an election among known wireless-consumable-memory systems. 6,302,527 describes a "radio frequency transmitter"/"radio frequency receiver" pair for a replaceable printing component; 6,938,976 describes transponder/transceiver RF polling; 7,212,637 is literally titled "Cartridge validation with radio frequency identification"; and WO 97/28001 discloses an electromagnetic link to an electronic label on each cartridge. Any of these, alone or in combination, discloses the claimed RF element.

Combination D (claims 8 and 15 — location identifier) — 7,137,684 + 6,676,240 + carriage-indexing art

Claim 8 (configuration instructions "identify a location of at least one other ink tank") and claim 15 (move the carriage to the identified location, then perform the second memory operation) are well addressed by 7,137,684's step of "defining a position of the enabled cartridge" and by the general carriage-indexing art of record, including 6,676,240's requirement that the RF linking device be docked "so that there is substantially no relative movement" between the marking engine and the printer's linking device. The '498's own background admits the carriage indexes to each default tank location — an admission that the positioning mechanism itself was conventional.

6. Dependent claims — obviousness gradient

Pattern: the apparatus claim 1 and method claim 10 are the hard targets; claims 3–9 and 12–15 are largely consequences of the count and of routine implementation choices, and would be difficult to sustain if the independent claims fall.

7. Why the record is genuinely mixed (the patentee's best defenses)

I would be doing you a disservice to present this as a clean rejection. The following are real:

1. Every cited reference stores data about this component, not about the set. 6,155,664 (characteristics of this cartridge), 6,302,527 (this component's ink level), 6,938,976 (type of this consumable), 7,137,684 (this cartridge's print-head ID), 6,672,695, 6,935,716, 7,212,637 (this cartridge's validation data). I found no reference that puts an aggregate install count on a consumable. The patentee can argue this is a change in kind, not degree, of the stored information — a classic "the prior art teaches in the opposite direction" argument: the field taught that each tag is a self-describing device, and the printer composes the picture from N independent reads.
2. 7,137,684's configuration knowledge is printer-derived, not tag-derived. Its detecting portion uses "separate lines coupled between the main control board" and the carriers. A patentee can argue that 7,137,684 not only fails to teach the count-on-the-tag limitation, but teaches away from it — its whole architecture answers "what's installed?" by bus detection rather than by data on the consumable.
3. Claim 1's data-content-only limitation. As noted, if the printed-matter doctrine is applied strictly, the patentee loses weight for the data content and claim 1 becomes very close to the art — but that cuts against the patentee, not for. Conversely, the patentee will argue In re Lowry and the specification's functional description to preserve weight. Either way, expect this to be the battleground.
4. Secondary considerations. The record I can verify (from the earlier section) shows commercial adoption and enforcement: the patent was carried through the Lexmark → Funai → Slingshot chain and asserted against HP in the Western District of Texas (family linked to 6:19-cv-00364; Slingshot's complaints also named the continuation 8,113,618). Patentee will argue nexus-based commercial success and copying. As the prior section noted, I cannot confirm which patents survived into the operative complaints or how each was dismissed, so this evidence is currently unquantified and would need docket-level proof.
5. Evidentiary gaps in my own work. I could not retrieve full text for US 6,158,850, US 6,672,695, US 6,935,716, or US 7,212,637 (tool-call limit reached). Claims 8/9/15 in particular deserve a check against 6,935,716 (Canon), which I expect to contain ink-tank memory content and possibly multi-tank verification, and against 7,212,637 for the RFID element. My Combination C is therefore under-supported relative to what a full-text pull would likely show.

8. Bottom line

• Claim 1 / claim 10 (independent): A prima facie §103 case is available but must be built on reasoning, not a single anticipating reference. The winning formulation is: US 6,155,664 (or 6,938,976) as primary for a data-bearing memory on an ink tank whose data drives printer/system behavior, in view of US 7,137,684 for a printer that must determine and act on the installed cartridge configuration (with four enumerated configurations and explicit position definition), with the KSR-recognized motivation supplied by the patent's own admitted problem (unnecessary memory operations → reduced print speed). The residual gap is the "total number" data element, which is where the case will be won or lost.
• Claims 3, 4, 5, 6, 7, 8, 9, 11, 12, 13, 14, 15: Individually and collectively highly vulnerable. Claim 9 (RFID) is obvious over 6,302,527, 6,938,976, and 7,212,637; claim 7 (operating modes) is obvious over 7,137,684; claim 4/13 (dual-tank second read) is obvious over 6,938,976's express "alternately communicate with the first and second transponders"; claims 8/15 (location) are obvious over 7,137,684's position definition plus 6,676,240/carriage-indexing art.
• Practical recommendation: Before relying on any of this, pull the full texts of US 6,158,850, US 6,672,695, US 6,935,716, and US 7,212,637, and run a targeted search for art that puts aggregate configuration/mode data (as opposed to per-component identity) on a consumable memory — e.g., art on "selective configuration" of printers from installed option modules, and the HP "replaceable part with integral memory" lineage (US 5,699,091, EP 0 789 322), which already frames consumable memory as storing "parameters for controlling operation of the apparatus." That single conceptual step — from part parameters to system parameters — is the most likely place a complete §103 rejection will be found.

Uncertainties to carry forward: (a) I did not verify US 6,158,850, US 6,672,695, US 6,935,716, or US 7,212,637 full texts; (b) the 2019 Slingshot v. HP per-patent dispositions are unconfirmed, so the secondary-considerations record is incomplete; (c) date inconsistency between the prompt (2026-04-26) and the session header (2026-09-30) remains unresolved and is irrelevant to the critical date but relevant to any post-issuance/validity posture; (d) all quoted reference language above is drawn from the search results cited inline and should be re-verified against the patentimages PDFs before being relied on in a filing.