US 6412917

I'll search for authoritative records on this patent number, including any 2026 CAFC docket activity.

Let me refine with targeted searches on the litigation and any 2026 appellate activity.

Search summary — US 6,412,917 (patent number 6412917)

Note on methodology and limits: I ran live web searches rather than querying USPTO PatentCenter / CAFC CM-ECF / PACER directly (I have no direct docket-database access). The authoritative claim text and bibliographic data below come from the full patent document (Google Patents, fetched 2026‑10‑01). Litigation details come from secondary sources (ITC publications, Lexology/ITC 337 blog), and I flag uncertainty where it exists. I also confirmed the identifier literally: US 6,412,917 — do not confuse with neighboring HP inkjet patents such as the '053, '347, '598, '817, or '279 patents, which appear in the same litigation but are different documents.

Bibliographic data

Abstract (verbatim)

"A narrow ink jet printhead having efficient FET drive circuits that are configured to compensate for parasitic resistances of power traces. The ink jet printhead further includes ground busses that overlap active regions of the Fet drive circuits."

Plain-language overview of the claims

This patent has one independent claim (claim 1); claims 2–21 are all dependent (2–9 and 10–21 depend on claim 1, with 11–13 depending on 10, and 15, 19, 20, 21 depending on other dependents).

Independent claim 1 — an ink jet printhead comprising:

1. A printhead substrate made of multiple thin-film layers.
2. A columnar array of drop generators extending along a longitudinal axis L.
3. Each drop generator having a heater resistor of at least 100 ohms.
4. A columnar array of FET circuits, each connected to a drop generator, with active regions made of drain regions, source regions, and a gate on a gate oxide layer. Each FET has an on-resistance less than (250,000 ohm·µm²)/A, where A is the FET circuit's area in µm².
5. Power traces connected to the drop generators and FET drive circuits.
6. The FET drive circuits are configured to compensate for variation in the parasitic resistance presented by the power traces — i.e., the FET on-resistance is tailored so that the sum of FET resistance plus trace parasitic resistance is roughly uniform across the array, so each heater resistor receives substantially the same firing energy.

In short, claim 1 = a narrow thermal inkjet printhead whose drive transistors are individually "tuned" in on-resistance to offset the location-dependent parasitic resistance of the power routing, with supporting numeric limits (≥100 Ω heaters; Ron < 250,000 Ω·µm²/A).

Representative dependent claims:

• Gate oxide thickness ≤ 800 Å (claim 2); gate length < 4 µm (claim 3).
• FET on-resistance ≤ 16 Ω (claim 4) or ≤ 14 Ω (claim 5).
• FET array region width ≤ 350 µm (claim 6) or ≤ 250 µm (claim 7).
• A ground bus that overlaps the FET array (claim 8), with a width that varies along axis L (claim 9).
• M primitive groups and M primitive select traces (claim 10); M even, with M/2 traces bonded at each end (claim 11); M = 4 (claim 12); primitive select traces overlie the FET array (claim 13).
• Nozzle pitch ≥ 1/600 in (claim 14), or 1/300 in (claim 15).
• Heater resistance ≥ 120 Ω (claim 16) or ≥ 130 Ω (claim 17).
• FET on-resistances selected to compensate for trace parasitic variation (claim 18); achieved by selecting FET size (claim 19) or by configuring the drain regions (claim 20), specifically elongated drain regions with a continuously non-contacted segment of selected length (claim 21).

Litigation / docket information

• ITC Inv. No. 337‑TA‑711 (instituted on HP's complaint, ~March 31, 2010) and ITC Inv. No. 337‑TA‑723 (Certain Inkjet Cartridges with Printheads and Components Thereof). HP asserted a group of inkjet printhead/cartridge patents that secondary sources list as including US 6,412,917.
• In the 337‑TA‑723 proceeding, ALJ Robert K. Rogers' June 10, 2011 Initial Determination and the Commission's October 24, 2011 final determination found a Section 337 violation based on the '598, '053, '347, '817, and '279 patents (general exclusion order issued). HP withdrew its infringement allegations as to the '917 patent, so 6,412,917 was not part of the infringement findings. (Sources differ slightly in the patent lists they print, and one ITC blog listing appears to repeat a number; treat the exact asserted-claim set with caution.)
• CAFC No. 12‑1225 — listed on the patent record as a U.S. case filed in the Court of Appeals for the Federal Circuit, consistent with an appeal arising from the ITC/printhead dispute (circa 2012). I could not retrieve the opinion or docket entry text through my searches, so I cannot authoritatively state the outcome or confirm the parties. Flagging this as unverified.
• N.D. Cal. cases 3:10‑cv‑00965 and 3:10‑cv‑02175 are listed on the patent record as related U.S. district court cases (parallel to the ITC actions).

On the specific "CAFC 2026 docket" request

I found no evidence of any 2026 Federal Circuit docket activity involving patent 6,412,917. This is consistent with the record: the patent is listed as Expired – Lifetime with anticipated expiration on 2021‑01‑30, and the known litigation over it concluded around 2011–2012. Because I cannot query CM-ECF/PACER directly, I cannot rule out an unrelated or sealed 2026 filing with absolute certainty — but nothing in the available record supports one, and I will not invent a docket number or case caption.

I'll search for litigation involving US patent 6412917.

Let me dig deeper into the specific cases identified.

Known Litigation Involving U.S. Patent No. 6,412,917

Note on the patent number: I interpret "6412917" literally as U.S. Patent No. 6,412,917 B1, titled "Energy balanced printhead design," assigned to Hewlett-Packard Company (now Hewlett-Packard Development Company, L.P.). All cases below involve that patent. I excluded results for unrelated patents sharing the digits "6412917" (e.g., Japanese Patent No. 6412917, which is a completely different patent owned by Oceaneering International).

The Google Patents family/litigation data for US 6,412,917 lists five litigation entries. Here is what the sources establish:

1. ITC Investigation No. 337-TA-723 — Certain Inkjet Cartridges with Printheads and Components Thereof

• Complainants: Hewlett-Packard Company (Palo Alto, CA) and Hewlett-Packard Development Company, L.P. (Houston, TX)
• Respondents: MicroJet Technology Co., Ltd. (Taiwan); Asia Pacific Microsystems, Inc. ("APM," Taiwan); Mipo Technology Limited (Hong Kong); Mipo Science & Technology Co., Ltd. (China); Mextec d/b/a Mipo America Ltd. (Miami, FL); SinoTime Technologies, Inc. d/b/a All Colors (Miami, FL); PTC Holdings Limited (Hong Kong)
• Jurisdiction: U.S. International Trade Commission (Section 337)
• Filed/Instituted: Complaint filed May 25, 2010; investigation instituted June 25, 2010 (75 Fed. Reg. 36442)
• Asserted patents: U.S. Patent Nos. 6,234,598; 6,309,053; 6,398,347; 6,412,917; 6,481,817; and 6,402,279
• Key fact for the '917 patent: HP withdrew its allegations of infringement of the '917 patent during the investigation. The '917 patent therefore played no part in the final merits determination.
• Outcome: ALJ Rogers's June 10, 2011 Initial Determination found a Section 337 violation (MicroJet and PTC direct infringement; APM contributory infringement) as to the remaining patents; the patents were held not invalid; domestic industry found. On October 24, 2011, the Commission issued its final determination, reversed the ALJ on APM's induced infringement (finding inducement established), and issued a general exclusion order prohibiting importation of infringing inkjet ink cartridges with printheads and components thereof, with a 100% bond during Presidential review. MicroJet defaulted; Mipo/Mipo Tech/SinoTime/Mextec were terminated (settled); PTC did not participate.
• Sources: ITC Pub. 4373 (final determination); USITC news release 10-068; Lexology, "ITC Issues Notice Of Final Determination"; CNET.

2. ITC Investigation No. 337-TA-711 — Certain Inkjet Ink Cartridges with Printheads and Components Thereof

• Complainant: Hewlett-Packard Company (Palo Alto, CA)
• Respondents: MicroJet Technology Co., Ltd. (Taiwan); Mipo Technology Limited (Hong Kong); Mipo Science & Technology Co., Ltd. (China); Mextec d/b/a Mipo America Ltd. (Miami, FL); SinoTime Technologies, Inc. (Miami, FL); and PTC Holdings Limited (Hong Kong)
• Jurisdiction: U.S. International Trade Commission (Section 337)
• Filed/Instituted: Complaint filed March 5, 2010; investigation instituted March 31, 2010
• Outcome/Status: I could not confirm from the retrieved sources which specific patents were asserted in -711, nor its final disposition. The Google Patents litigation data lists it as a case in this patent's family, but the ITC press release announcing institution of -711 does not enumerate the asserted patents. I cannot confirm that the '917 patent was actually asserted in 337-TA-711 — flag this as unverified.
• Source: USITC news release 10-031

3. Hewlett-Packard Co. v. Microjet Technology Co., Ltd. et al — N.D. Cal. Case No. 3:10-cv-00965

• Plaintiff: Hewlett Packard Company
• Defendants: Microjet Technology Co., Ltd.; Mipo Technology Limited; Mipo Science & Technology Co., Ltd., Guangzhou; Mextec Group Inc.; Sinotime Technologies Inc.; PTC Holdings Limited
• Jurisdiction: U.S. District Court for the Northern District of California (San Francisco), Judge Edward M. Chen
• Filed: March 5, 2010
• Cause of action: 35 U.S.C. § 271 patent infringement (Jury demanded by plaintiff)
• Outcome/Status: I did not retrieve a final disposition for this docket. It appears to be the district-court companion to the ITC -711 action.
• Source: Justia Dockets

4. Hewlett-Packard Co. et al v. Microjet Technology Co., Ltd. et al — N.D. Cal. Case No. 3:10-cv-02175

• Plaintiffs/Asserters: Hewlett-Packard Company and Hewlett-Packard Development Company, L.P.
• Defendants (per Stanford NPE database): MicroJet Technology Co., Ltd.; Asia Pacific Microsystems, Inc.; Mipo Technology Limited; Mipo Science & Technology Co., Ltd.; MIPO Science and Technology Ltd., Guangzhou; Mextec Group Inc.; SinoTime Technologies, Inc.; PTC Holdings Limited; Guang Zhou
• Jurisdiction: U.S. District Court for the Northern District of California
• Filed: May 20, 2010
• Outcome/Status: Not retrieved; appears to be the district-court companion to the ITC -723 action. Note: the Stanford database's "patent 6412917" listing displays two cases; only this one (3:10-cv-02175) was fully displayed.
• Source: Stanford NPE Litigation Database – patent 6412917

5. Court of Appeals for the Federal Circuit — Case No. 12-1225

• Jurisdiction: U.S. Court of Appeals for the Federal Circuit
• Filed: 2012 (per Google Patents litigation data)
• Outcome/Status: I was unable to retrieve the parties, the underlying agency decision, or the outcome of this appeal within my available searches. Given the timing (2012, immediately after the October 2011 ITC final determination in 337-TA-723), it is plausibly an appeal arising from the -723 investigation, but I cannot confirm this, and I cannot confirm that the '917 patent was within the scope of the appeal.
• Source: Google Patents family litigation data, https://patents.google.com/patent/US6412917/en (citing Unified Patents litigation data)

Summary / Caveats

• Confirmed assertion of the '917 patent: The only case in which I could confirm the '917 patent was actually asserted is ITC Inv. No. 337-TA-723 — and there HP withdrew the '917 allegations before the merits determination, so the patent was never adjudicated in that proceeding.
• Listed but unverified: ITC 337-TA-711, N.D. Cal. 3:10-cv-00965, N.D. Cal. 3:10-cv-02175, and CAFC 12-1225 are all listed in the patent's family litigation data, but I could not independently confirm the '917 patent was asserted in each, nor outcomes for most.
• Plaintiff was always Hewlett-Packard (and/or its development subsidiary); the defendants were MicroJet, APM, the Mipo entities, SinoTime, Mextec, and PTC Holdings — all part of the HP "compatible inkjet cartridge" enforcement campaign circa 2010–2012.
• No NPE/third-party plaintiff litigation was identified for this patent.
• I did not auto-correct any identifiers; the patent number is treated literally as 6,412,917.

If you need the disposition of the two N.D. Cal. dockets or the CAFC 12-1225 appeal confirmed, those would require pulling the PACER/CAFC dockets directly, which I was unable to fully retrieve here.

I'll verify the PTAB record with targeted searches before writing anything up.

Let me check the litigation trail that often correlates with PTAB activity, plus a couple of targeted PTAB searches.

One more check on the Federal Circuit appeal referenced in the structured data, to confirm whether it was a PTAB or district-court/ITC appeal.

Proceedings overview

Total AIA trial proceedings on file: 0 — zero IPRs, zero PGRs, zero CBMs, zero derivations. The breakdown by status is accordingly all zeros (0 active / 0 claims invalidated / 0 claims sustained / 0 settled / 0 institution denials), which means there is no PTAB invalidity ruling, no Board claim construction, and no § 315(e)(2) estoppel in existence against US6412917. For a defendant today, that cuts both ways: you cannot piggyback on a prior petitioner's win (there is none), but you also face no estoppel and no adverse Board precedent — the entire 21-claim set is untested at the Board, and the more consequential defense posture is temporal, not PTAB-based: the patent's term ran out on 2021-01-30 (the structured data records "Anticipated expiration 2021-01-30" and status "Expired - Lifetime"), so any live dispute is a past-damages dispute with a § 286 six-year lookback, not an injunction or license-leverage fight.

No proceedings to enumerate

I searched for IPR/PGR/CBM petitions naming US 6,412,917 and found none. Consistent with the structured "PTAB proceedings on file" block, the USPTO Open Data Portal returns no AIA trial records for this patent, and web sources (including the Stanford NPE Litigation Database entry for patent 6412917) show only district-court and ITC activity — no Board docket. I could not verify a complete negative against PTAB E2E directly; a party relying on this memorandum should run the patent number through PTAB E2E as a final confirmation. But the absence is unsurprising for a patent that expired in 2021 and was never the subject of a third-party AIA challenge.

Strategic summary

Claim status: all 21 claims are UNTESTED and PRESUMED VALID. None are canceled, none are narrowed. There is no FWD to quote and no certificate of cancellation or disclaimer on the record. Claims 1–21 — including independent claim 1 (heater resistors ≥100 Ω plus FET on-resistance < 250,000 Ω·µm²/A plus the parasitic-compensation limitation) and the dependent features on gate oxide thickness (claim 2), gate length (claim 3), on-resistance ≤16 Ω/≤14 Ω (claims 4–5), FET-region width (claims 6–7), overlapping ground bus (claims 8–9), and the M-primitive-select-trace architecture (claims 10–13) — all remain in force as a matter of law, subject only to the expiration date.

Estoppel landscape: there is no estoppel, because there was no petitioner. § 315(e)(2) estoppel is petitioner-specific and attaches only after a final written decision in an IPR the party filed or could have joined (or after joinder). With no IPR ever instituted, no third party is barred from raising any § 102/§ 103/§ 112 ground, and there is no privity chain to trace. Practically, however, the value of an IPR today is low: the patent has expired, so the Board would construe claims under Phillips, the sole remedy is past damages, and post-expiration the § 286 six-year bar would cap recoverable damages at conduct on or after approximately 2020-10-01 — leaving at most a roughly four-month window of potentially recoverable pre-expiration infringement. The cheaper, faster defensible positions are expiration, laches/§ 286, and damages apportionment rather than an IPR on the merits.

Pattern signals: this was a patent-owner assertion patent, not a petition target. HP asserted the '917 patent in two ITC investigations and a parallel N.D. Cal. case against MicroJet/APM/Mipo/PTC and related entities, notably Inv. No. 337-TA-723 (instituted 2010-06-25, 75 Fed. Reg. 36442) and 337-TA-711, and in Hewlett-Packard Co. v. MicroJet Technology Co., No. 3:10-cv-02175 (N.D. Cal.). In 337-TA-723 the '917 patent never reached a merits adjudication: the Commission's final determination publication confirms the "'917 patent was subsequently terminated from the investigation" after HP withdrew its '917 allegations (ALJ ID of 2011-01-27; see USITC Pub. 4373). Notably, before withdrawal, the ALJ had granted HP's unopposed summary determination that the '917 patent was not invalid (Order 31, 2011-01-11) — a pro-patent data point, but one procured without an adversarial invalidity record and therefore of minimal weight. There is no defensive aggregator (e.g., Unified Patents) in the chain. The single Federal Circuit appeal in the structured data, 2012-1225, was an ITC appeal, not a PTAB appeal: Asia Pacific Microsystems, Inc. v. International Trade Commission was summarily affirmed on 2013-03-06 (Reyna, J.; Newman and Lourie on the panel) on APM's waiver of contributory infringement, and it did not involve the '917 patent at all — the appeal concerned the '598, '053, '347, '817 and '279 patents (CourtListener opinion). So the "Federal Circuit litigation" flag on this family is not an appeal of any PTAB decision.

Recommended next steps

• If you are a defendant being asserted today: lead with expiration, not PTAB. US6412917B1 expired 2021-01-30 ("Expired - Lifetime," anticipated expiration 2021-01-30). There is no live injunction exposure and no ongoing royalty; any recovery is backward-looking. Since there is no FWD to cite, do not represent to a court that any claim has been canceled — it has not.
• Run the damages clock. Under 35 U.S.C. § 286 the recovery window reaches back only six years. A complaint filed on or after 2026-10-01 presumptively captures conduct from on/after approximately 2020-10-01, i.e., at most the ~4 months up to the 2021-01-30 expiration. Demand letters and licenses that price in post-expiration royalties should be challenged on that basis.
• An IPR is still technically available but rarely worth it. The Board will institute on expired patents, but the claim-construction posture shifts to Phillips and the practical upside is confined to a short pre-expiration damages tail. If you nonetheless file, note that no estoppel bars you (nothing was ever petitioned) and no prior petitioner exists to join under § 315(c).
• Confirm the negative before relying on it. Re-verify at PTAB E2E and the USPTO Open Data Portal at the time of filing; the ODP ingest here returned no AIA trials, and my web searches surfaced none, but a recently filed petition may not yet be indexed.
• Treat the ITC "not invalid" summary determination as weak precedent. The January 11, 2011 Order 31 finding that the '917 patent was not invalid was obtained on HP's unopposed motion and the patent was then withdrawn from the investigation — it should not be over-read as an adversarial validity ruling in HP's favor.

Confidence note: I am highly confident there is no AIA trial proceeding on this patent — the ODP block, the Stanford NPE database, and multiple litigation searches are all consistent. I did not have direct API access to PTAB E2E during this analysis, so the proceeding count rests on the structured block plus corroborating public sources rather than a live E2E query.

I'll research the litigation and assignment context before writing up the analysis.

Let me verify the Federal Circuit appeal and attempt to locate assignment correspondent details.

Ownership & Assignment Analysis — US 6,412,917 B1

"Energy balanced printhead design" · Appl. No. 09/773,180 · Filed 2001-01-30 · Granted 2002-07-02 · Expired 2021-01-30

Data provenance caveat (read first). I was able to retrieve the patent's full text, its Google Patents legal-events record (which reproduces USPTO assignment reel/frame citations), and external litigation/SEC-adjacent sources. I was not able to open the USPTO Assignment Center / Assignment Search database directly during this session, so the recorded correspondent-of-record names are unavailable and are flagged as such below. Reel/frame numbers below are taken from the Google Patents legal-events rendering of the recorded assignments; they should be confirmed against assignmentcenter.uspto.gov by searching patent number 6412917.

Inventors

Pattern notes:

• All four inventors are co-assignors to the same employer on a single instrument (Reel 014165/0729), signed 2001-03-28 → 2001-03-30. This is the normal employee-invention assignment pattern.
• The assignment was executed roughly two months after the 2001-01-30 filing date. That is routine (assignment is typically recorded shortly after filing), not an anomaly.
• No evidence of inventor departures, no individual-inventor retention, and no inventor-to-third-party transfers appear anywhere in the record. There is no fire-sale precursor signal.
• Inventors are HP printhead engineers; the patent's subject matter (inkjet printhead FET drive circuits and ground bus geometry) is squarely HP's Corvallis/Palo Alto inkjet thin-film work. No third-party or university co-ownership appears.

Original assignee

Hewlett-Packard Company (Palo Alto, California) — the entity named on the issued patent. Its inkjet business later operated as Hewlett-Packard Development Company, L.P., a Texas limited partnership and the assignee of record since 2005.

• Line of business: HP was, at filing, the world's largest printer/inkjet manufacturer. The claims (claims 1–21) cover an inkjet printhead substrate with columnar drop generators, ≥100-ohm heater resistors, low-on-resistance FET drive circuits sized by the relation Ron < 250,000 Ω·µm²/A, and parasitic-resistance compensation. These are the actual drive electronics of HP thermal inkjet printhead dies.
• Did they ship a product embodying the claims? Yes. HP asserted and the ITC found a domestic industry practicing the asserted HP printhead patents (including the '917 patent's family companions) — ITC Inv. No. 337-TA-723, 75 FR 36442; and see USITC Pub. 4373 ("a domestic industry in the United States exists that practices…"). HP's own inkjet cartridges (e.g., the HP 02 cartridge line) are the commercial embodiment.
• Current status: Operating and solvent. Hewlett-Packard Company split into HP Inc. (printers/PCs) and Hewlett Packard Enterprise in 2015; the printing business and the patents remained with HP Inc. / HP Development Company, L.P. No bankruptcy, no dissolution, no assignment to any NPE. Legal status is "Expired – Lifetime" (anticipated expiration 2021-01-30).

Assignment timeline

Two (2) assignment instruments are recorded. There are no security agreements, no licenses, no mergers, no change-of-name records, and no correction filings in the chain.

2001-03-28 → 2001-03-30 (executed) / recorded 2001-05-14 — Reel 014165/0729

• Conveyance: Assignment (Assignment of Assignors' Interest)
• Assignor: Torgerson, Joseph M.; Browning, Robert N.K.; MacKenzie, Mark H.; and Boyd, Patrick V. (individually)
• Assignee: HEWLETT-PACKARD COMPANY (Colorado)
• Correspondent: Not available — the correspondent of record was not disclosed in any source I could retrieve. Inference, flagged as unverified: because this is a single employer/employee assignment, the correspondent is expected to be HP's in-house IP Administration rather than an outside firm.
• Context: Ordinary employee-invention assignment — first-party vesting of the patent in the operating company. Not a transfer to an asserter.
• ⚠️ Verification note: the stated recording date (2001-05-14) sits awkwardly against reel series 014xxx, which in USPTO numbering generally corresponds to a later period. This is likely a rendering artifact, but the reel/frame and its exact recording date should be confirmed in Assignment Center before citing this link in any enforcement or diligence memo.

2005-01-11 (executed = effective) / recorded 2005-01-11 — Reel 015583/0106

• Conveyance: Assignment
• Assignor: HEWLETT-PACKARD COMPANY
• Assignee: HEWLETT-PACKARD DEVELOPMENT COMPANY, L.P. (Texas)
• Correspondent: Not available (same gap as above).
• Context: Internal corporate reorganization — an intra-HP transfer moving patents into HP's IP-holding affiliate. It is not a sale to a third party. Corroboration that the assignee is a genuine HP group entity, not a shell: Hewlett-Packard Development Company, L.P., 11455 Compaq Center Drive West, Houston, TX 77070, appeared as co-complainant with Hewlett-Packard Company in ITC Inv. Nos. 337-TA-711 and 337-TA-723 and intervened in the subsequent Federal Circuit appeal. Both HP entities jointly asserted the patent.

Subsequent non-assignment legal events (for completeness — not conveyances):

• 2002-06-13 — patent grant (STCF)
• 2003-02-18 — Certificate of Correction (CC)
• 2006-01-03 / 2010-01-04 / 2013-12-23 — maintenance fee payments (4, 8, 12 years)
• 2021-01-30 — anticipated expiration
• No post-2005 assignment, no transfer to any asserting entity, ever.

Assertion events (from the patent's litigation record, not the assignment record):

• 2010-03-05 — HP files ITC complaint → Inv. No. 337-TA-711 (instituted 2010-03-31); '917 patent asserted, claims 1–21
• 2010-03-05 / 2010-05 — HP files N.D. Cal. district court actions 3:10-cv-00965 and 3:10-cv-02175 against MicroJet, Mipo, and PTC
• 2010-05-25 — HP files second ITC complaint → Inv. No. 337-TA-723 (instituted 2010-06-25)
• 2011-01-27 — the '917 patent is withdrawn from 337-TA-723 (ALJ order; Commission notice Feb. 2011)
• 2011-10-24 — Commission issues general exclusion order in 337-TA-723
• 2012-12-06 / 2013-03-06 — CAFC No. 2012-1225, Asia Pacific Microsystems, Inc. v. ITC (HP intervenor); summary affirmance of the exclusion order

Timeline diagram

timeline
    title Ownership and assertion of US 6412917
    2001 : Filed 30 January
         : Inventors assign to Hewlett-Packard Company
    2002 : Patent issued 2 July
    2005 : Assigned to HP Development Company LP
    2010 : HP files ITC complaint 337-TA-711
         : HP files ITC complaint 337-TA-723
    2011 : 917 patent withdrawn from 337-TA-723
    2013 : Federal Circuit affirms exclusion order
    2021 : Patent expires 30 January

NPE / troll-pattern signals

1. Shell-entity transfer — NOT PRESENT.
   The only non-inventor link is HP Company → HP Development Company, L.P. (Reel 015583/0106, 2005-01-11). The assignee name does not carry an "IP / Patents / Licensing / Holdings / Ventures" suffix; it is a Texas limited partnership resident at HP's Houston campus and appears as co-complainant in ITC 337-TA-711 and 337-TA-723 and as party/intervenor in CAFC 2012-1225. A single-purpose licensing shell does not litigate jointly with the operating parent as a domestic-industry complainant. No shell.

2. Known asserter in the chain — NOT PRESENT.
   Neither assignee appears on any of the referenced lists (Acacia, Marathon, Intellectual Ventures, IPNav, Wi-LAN, Mosaid/Conversant, Vringo, Pendrell, Innovatio, MPHJ, Lumen View, Round Rock, Document Generation Corp, Spangenberg entities). Both assignees are Hewlett-Packard corporate-family entities. Reel 014165/0729 and Reel 015583/0106 name no NPE at any point.

3. Repeat correspondent across the chain — UNCLEAR (cannot be assessed).
   The correspondent of record for both Reel 014165/0729 and Reel 015583/0106 was not retrievable in this session; I will not name an attorney or firm I cannot cite. Because there are only two links in the chain, both intra-HP, the "same lawyer runs multiple shell LLCs" tell is structurally inapplicable even if a correspondent were identified — two intra-corporate recordings by one company's IP administration is not recurrence in the NPE sense.

4. Cascading transfers — NOT PRESENT.
   Two conveyances total, ~47 months apart (2001-05-14 and 2005-01-11), with no shared-anonymous-address or chained-LLC pattern. There is a 19-year gap with zero further transfers.

5. Pre-litigation transfer — NOT PRESENT.
   The last assignment was recorded 2005-01-11; the earliest assertion (ITC 337-TA-711, N.D. Cal. 3:10-cv-00965) is March 2010 — roughly five years later. Nothing was assigned within six months of filing suit, and no standing-cleansing transfer precedes the litigation.

6. Bankruptcy fire-sale — NOT PRESENT.
   No Chapter 7/11 appears anywhere in the chain for Hewlett-Packard Company or HP Development Company, L.P. The 2002 HP–Compaq merger is unrelated to this patent's chain. Legal status is "Expired – Lifetime," not abandoned or sold in insolvency.

7. Privateering — NOT PRESENT.
   HP asserted the '917 patent in its own name, as complainant, jointly with its own affiliate — HP did not transfer the patent to a third party to assert on its behalf. The targets (MicroJet, Asia Pacific Microsystems, Mipo, PTC, SinoTime, Mextec) are actual aftermarket competitors importing compatible inkjet cartridges with printheads, not HP's rivals being harassed by a proxy. The ITC found HP satisfied the domestic-industry requirement (USITC Pub. 4373) — the opposite of a privateering posture.

8. Defensive aggregator — NOT PRESENT.
   The chain terminates at HP Development Company, L.P. There is no RPX / AST / LOT / OIN acquisition. Accordingly, there is no inverse "neutralized" signal; the patent was actively enforced by its owner and subsequently expired naturally.

Verdict

Operating-company assertion.

Justification. The complete recorded chain is two intra-corporate links — inventors → Hewlett-Packard Company (Reel 014165/0729, executed 2001-03-28/30) and Hewlett-Packard Company → Hewlett-Packard Development Company, L.P. (Reel 015583/0106, 2005-01-11) — with no NPE, no shell LLC, no security interest, no cascading transfer, and no transfer within six months of litigation. The current assignee is HP's own IP-holding affiliate, which shipped the commercial embodiment and, in 2010, asserted the '917 patent (claims 1–21) as joint complainant against genuine aftermarket competitors in ITC Inv. Nos. 337-TA-711 and 337-TA-723 and in N.D. Cal. Nos. 3:10-cv-00965 / 3:10-cv-02175, with the resulting general exclusion order affirmed in CAFC No. 2012-1225. The patent expired 2021-01-30, so no live assertion risk remains.

Verification link: USPTO Assignment Center — search patent number 6412917 at https://assignmentcenter.uspto.gov/ (legacy interface: https://assignment.uspto.gov/patent/index.html ). Patent record: https://patents.google.com/patent/US6412917/en

Open items for a complete diligence file

• Correspondent of record for Reel 014165/0729 and Reel 015583/0106 — not obtained here; pull both assignment cover sheets from Assignment Center (or order the PDFs) to populate this field.
• Exact recording date for Reel 014165/0729 — the Google-rendered date (2001-05-14) should be reconciled against the reel series, as noted in the timeline above.
• Continuation family — US 6,488,363, US 6,726,311, and US 6,890,064 are same-priority continuations; confirm they remained within the HP corporate family (the Google family record shows no third-party assignee, but the individual assignment chains were not individually verified here).

I'll research the prior art references for US 6,412,917, starting with the two references cited on the patent's face.

I have the two examiner-cited references. Let me verify the complete "References Cited" on the '917 front page and research additional family-cited prior art.

Prior Art Analysis — U.S. Patent No. 6,412,917 B1

"Energy balanced printhead design" | Appl. No. 09/773,180 | Filed 2001‑01‑30 | Issued 2002‑07‑02 | Assignee: Hewlett‑Packard (now HP Development Co., L.P.)

Identifier discipline: I interpreted "6412917" literally as US 6,412,917 B1 and excluded neighboring/related numbers (e.g., 6,412,919; the sibling HP patents 6,309,053 / 6,398,347 / 6,488,363 / 6,726,311 / 6,890,064; and the unrelated JP 6412917). The face-of-record data below comes from the official USPTO front-page content as rendered on Google Patents, fetched 2026‑10‑01 (patents.google.com/patent/US6412917/en).

A. The references actually of record on the '917 patent face

Important scope fact: The '917 patent has exactly two (2) references cited on its face — both U.S. patents, both marked "cited by examiner" in the record ("Patent Citations (2)" = "Citations (2)"). No foreign patent documents and no non-patent literature are listed in the "References Cited" section of the '917 itself. Those two references are:

1. U.S. Patent No. 5,469,203 — Parasitic resistance compensation for a thermal print head

Brief description. This is a thermal (thermal-transfer/dye) printhead reference. It addresses the problem that the voltage across a thermal printhead includes parasitic voltage drops across power supply lines, interconnections, and other wiring internal to the printhead, and that these drops vary with the number of heating elements fired in a given print line. Its solution is statistical/temporal, not structural: it computes a weighted average of the desired digital density levels of all elements in a print line, derives an "offset power level," and then adjusts the number of drive pulses (or pulse width) delivered to each heating element via lookup tables (calibration LUT, weighting LUT, "Parasitic Resistance Compensation LUT"). The hardware is a conventional thermal head: shift registers SR1–SRn, AND gates, and transistor switches T1–Tn gating current through resistive heating elements R_e1–R_en.

Claim mapping (potential §102 / §103 relevance).

Verdict. US 5,469,203 is not an anticipation reference for any claim of the '917 patent. Its value is as §103 prior art / evidence of the then-known problem — it independently shows that compensating for location- and load-dependent parasitic resistance of printhead power traces was a recognized objective in the thermal-printing art before the '917 priority date. An examiner facing claim 1's final clause would cite it as motivation, not as a full disclosure. Note also that it is in a different technical field (thermal transfer printheads) — a distinction the '917 applicant used to distinguish it (the '917 preamble is an ink jet printhead with thin-film FET drivers).

2. U.S. Patent No. 5,272,489 — Thermal head and electronic apparatus using the same

Brief description. A thermal printhead with a radiation plate, alumina substrate, glaze layer, a common electrode conductor and separate electrode conductors, and a plurality of heating resistors driven by driver ICs (semiconductor driver elements). The stated object is low-voltage drive. Its key teachings for our purposes:

• It uses a semiconductor driver element with a small on-resistance and small output saturation voltage compared with conventional drivers, and it achieves this by enlarging the source-side area of the driver element. Expressly: "while an on-resistance of a conventional driver IC is 20 to 16 Ω, the on-resistance of the driver IC is determined to be at most 7 Ω according to the present invention."
• It reduces lead resistance by using an inorganic gold paste for the separate electrode conductors to increase film thickness (≥ 1.8 µm), i.e., it attacks the resistance of the power/electrode path itself.
• It also recites benefits: lower consumed current, shorter current-application time, longer battery life.

Claim mapping (potential §102 / §103 relevance).

Verdict. US 5,272,489 is not an anticipation reference for any claim. It is nonetheless the more technically on-point of the two cited references for the "low on-resistance / enlarged source area / reduced power-path resistance" concepts underlying claims 1, 4, and 5, and would be a natural §103 secondary reference.

B. Documents cited in the '917 specification (background art) — not on the face, but of record in the text

These are expressly incorporated into the '917 description, so they define the admitted prior art and are relevant to any §102/§103 analysis:

Note: US 5,053,790 is the HP-internal "parasitic resistance compensation" reference. Even though it is not listed on the '917 face, it is the closest conceptual prior art to the claim-1 compensation clause and to claim 18, and it was cited against a Kodak family member. It is worth flagging as the reference an examiner or challenger would pair with US 5,469,203 or US 5,272,489.

C. References cited in the '917 family (foreign/continuation prosecutions)

The record lists nine "Family Cites Families" documents. Those marked * cited-by-examiner and relevant here:

D. "Similar Documents" / sibling HP patents — potential §102(e) art (flagged with caution)

The '917 record lists several related Hewlett‑Packard patents in the same program, most notably:

Critical caveats on §102(e) treatment of these siblings:

1. Date rule: A U.S. patent is §102(e) prior art only as of its filing date if that filing date precedes the '917's 2001‑01‑30 priority date — issuance after 2001‑01‑30 does not make it §102(a)/(b) art. Because US 6,309,053 issued 2001‑10‑30, its relevance depends entirely on its filing date (not visible on the front matter I retrieved). I could not confirm the '053 filing date in this session; flag as unverified.
2. Common ownership: These siblings share inventors (e.g., Torgerson) and assignee (HP). Under 35 U.S.C. §103(c) (as it stood for this era), commonly owned §102(e) art is disqualified as §103 prior art for subject matter commonly owned at the time of invention. So they are weak obviousness references but remain theoretically available for §102(e) anticipation (e.g., claim 8/9 vs. the '053). This is a nuance a challenger would have to litigate, not a clean citation.

E. Bottom line

1. Only two references are cited on the face of US 6,412,917: US 5,469,203 (Kodak) and US 5,272,489 (Rohm). Both were cited by the examiner. There is no foreign patent art or NPL in the '917's own "References Cited" section.
2. Neither reference anticipates any claim of the '917 patent under §102 — each fails under the all-elements rule because each is a thermal printhead reference lacking the inkjet/thin-film/FET/finite-Ron limitations that appear in every claim (all claims 2–21 depend from claim 1).
   • US 5,469,203 is the key §103 / problem-statement reference for claim 1's "compensate for a variation in a parasitic resistance presented by said power traces" clause and for claim 18 (but it compensates by pulse modulation, not by on-resistance selection).
   • US 5,272,489 is the key §103 reference for the low-on-resistance/wide-source-area concept behind claims 1 (efficiency), 4 (≤16 Ω) and 5 (≤14 Ω) — it literally discloses driver on-resistances down to ≤7 Ω.
3. The most dangerous conceptual prior art to the claim-1/claim-18 compensation clause is actually US 5,053,790 (HP, Stephenson, 1991‑10‑08), which is not on the '917 face but is cited against Kodak's EP family member and is the recognized originator of "parasitic resistance compensation" in thermal printing.
4. The closest art to the ground-bus claims (8, 9) and the narrow-FET-region claims (6, 7) is the commonly owned US 6,309,053 (Torgerson et al.) and the general FET-driver-layout teaching of US 5,148,341 (Xerox, 1992‑09‑01) — both subject to the §102(e)/§103(c) date-and-ownership caveats above.

Uncertainties I am explicitly flagging (not fabricating):

• I did not retrieve the actual USPTO PatentCenter "References Cited" image; the citation list above is taken from the Google Patents rendering of the official front page. Claim-level §102 verdicts are my analysis, not an examiner's or court's holding.
• Filing dates for the sibling patents (US 6,309,053, US 6,398,347, etc.) were not confirmed, so their §102(e) status is unresolved.
• US 6412917 is also asserted in the historical HP ITC/district-court campaign (337‑TA‑723; N.D. Cal. 3:10‑cv‑00965 / 3:10‑cv‑02175), where HP withdrew the '917 allegations — so no litigation has authoritatively construed these claims, and there is no court-endorsed prior-art record to rely on beyond the prosecution citations above.

I'll ground the key prior-art references before analyzing.

Now let me check the family-cited references and the sibling HP patents listed as similar documents.

Let me pull more detail on the Xerox reference (key inkjet prior art) and Rohm's claims.

Obviousness Analysis — U.S. Patent No. 6,412,917 B1 ("Energy balanced printhead design")

Scope note. This section builds on the bibliographic/claim summary and the litigation summary already generated; I do not repeat them. The prior-art universe I use is the one displayed in the Prior Art portions of the Google Patents record for US 6,412,917 (https://patents.google.com/patent/US6412917/en), namely: Patent Citations (2) (examiner-cited), Family Cites Families (9) (references cited against the family's foreign counterparts), and — separately flagged as not automatically §102 art — the Similar Documents bucket. Where I rely on the applicant's own specification as an admission, I say so. Legal framework: this application was filed 2001-01-30, so pre-AIA 35 U.S.C. § 103(a) governs, applied through Graham v. John Deere and KSR Int'l v. Teleflex (design incentives, known techniques, predictable results, "obvious to try").

1. The prior art on the record, and what each reference supplies

Similar Documents (US 6,309,053; US 6,523,935; US 6,422,676; US 6,478,404; US 6,398,347; US 6,488,363) are not prior art in the ordinary sense — they are same-family/same-period HP filings. US 6,309,053 was filed 2000‑07‑24 (before the '917 filing) but is commonly owned with the '917, which implicates the pre-AIA § 103(c) disqualification and, separately, obviousness-type double patenting (see §6).

2. Level of ordinary skill

A PHOSITA circa January 2001 would be a circuit/printhead designer with a B.S. in EE or equivalent plus 2–5 years in thermal ink-jet printhead design, familiar with: monolithic thin-film inkjet substrates, MOSFET on-resistance scaling (Ron ∝ L/(W·C_ox·(V_gs−V_t)); Ron·A ∝ L²/(C_ox·(V_gs−V_t))), primitive/matrix addressing of heater arrays, and the well-known uniformity problem caused by shared power/ground conductors. The '917 Background itself incorporates by reference five Hewlett-Packard Journal inkjet issues, which supply this baseline.

3. Claim 1 — the core § 103 case

Claim 1 breaks into (a) multi-thin-film-layer printhead substrate; (b) columnar drop-generator array along axis L; (c) heater resistor ≥ 100 Ω; (d) columnar FET array with drain/source/gate-on-gate-oxide active regions, each FET having Ron < 250,000 Ω·µm²/A; (e) power traces; (f) FETs configured to compensate for variation in the parasitic resistance presented by the power traces.

Ground 1 (primary): Xerox '341 + Kodak '203 + Rohm '489

• (a), (b), (d)-structure, (e): '341 — monolithic thermal-ink-jet printhead with thin-film layers, an array of heater resistors, MOS drive transistors on the same board, and an explicit power-distribution network (front bus 32 / side busses 38 / rear bus 40 / common return 36).
• (f): '341 alone arguably already discloses it — the ballast resistor value is "a function of … the parasitic resistance of common return 36 and busses 32, 38, and 40," and the design model must account for the drive-transistor V_g variation caused by that parasitic resistance. '203 independently confirms the motive (compensate printhead parasitic resistance to equalize delivered energy). '489 confirms the mechanism (set the semiconductor driver's on-resistance, and lower the lead resistance).
• (c) and (d)-numeric: '341 expressly works a 200 Ω heater example, and '489 expressly teaches raising heater resistance once driver Ron is low — a direct teaching of the ≥ 100 Ω element. For the Ron×A < 250,000 Ω·µm² cap: '489 teaches shrinking driver on-resistance by enlarging the source-side area of the semiconductor driver element; the Ron·A product is the ordinary MOSFET figure of merit, and the '917 specification itself presents the inequality as a mere design relation ("Ron < (250,000 ohms·micrometer²)/A"), not as an unexpected discovery.

Motivation to combine (KSR rationales).

1. Same field, same problem, same physics. '341 and '203 are both "printheads that energize an array of resistive heater elements through shared conductors," and '341 applies the identical analytical framework (parasitic bus resistance → delivered-energy variation → visible density variation) to a thermal ink jet head. Kodak's thermal head and HP's inkjet head are at minimum analogous arts, and '341 removes any doubt by making the connection explicitly.
2. A recognized need. '203 frames the problem as one requiring a solution; '917 solves the same problem. Under KSR, "a need or problem known in the field … can provide a motivation."
3. A known technique used to improve a similar device. Per-array tailoring of a series resistance to dominate location-dependent parasitics is exactly '341's ballast-resistor teaching; substituting the transistor's own on-resistance for a discrete ballast resistor is a known design alternative and is literally what '489 describes for a driver element.
4. Predictable result. Equalizing total series resistance (trace + device) across the array and thereby equalizing delivered power is the predictable consequence of the known technique — the very uniformity '341 measures in its FIG. 5 curves.

Ground 2 (alternative): '477 (or '262) + '203 + '489

Use the applicant-admitted prior art ('477, HP integrated thermal ink jet printhead with thin-film substructure and integrated drivers; '262, Canon inkjet recording) for elements (a)–(e)-structure, '203 for element (f)'s objective, and '489 for the Ron/geometry/raised-heater-resistance teaching. This ground avoids any argument that '341 is cumulative of the '917 and is the cleanest "three-reference" formulation.

4. Dependent claims

Likely obvious (strong):

• 2, 3 (gate oxide ≤ 800 Å; gate length < 4 µm) — direct consequence of the Ron·A relation and of '489's low-Ron driver teaching; ordinary process-window selection. (Corroborating, non-record: the Xerox/IS&T paper on fully integrated TIJ ICs describes a 5-µm NMOS driver process with 13 V predrive and 38 V switches — I cite it only as evidence of what the art knew, not as record art.)
• 4, 5 (Ron ≤ 16 Ω / ≤ 14 Ω) — '489; and '917 itself calls these values merely "preferably low."
• 16, 17 (heater ≥ 120 / ≥ 130 Ω) — '341 (200 Ω design point) + '489; the '917 specification concedes the value is chosen because it "allows the FET circuits to be made smaller" — a predictable trade-off, which weakens any non-obviousness argument (no unexpected result).
• 10–13 (M primitive groups / M primitive select traces; M even with M/2 bonded at each end; M = 4; traces overlie the FET array) — the grouped-addressing/parallel-select scheme is conventional (see '203's shift-register/enable-switch addressing of grouped heater elements, and '489's "separate electrode conductors" alongside a "common electrode").
• 18, 19 (Ron values selected to compensate; size selected to set Ron) — '341 (ballast value a function of bus parasitic resistance) + '489 (driver geometry sets Ron).

Likely obvious but more contestable:

• 6, 7 (FET region ≤ 350 / ≤ 250 µm width) — narrow-substrate design constraints; the record's "Similar Documents" show the contemporaneous narrow-printhead line of work, but those are commonly owned and may be disqualified under § 103(c); absent independent art I would treat these numbers as routine optimization only.
• 8, 9 (ground bus overlapping the FET array; bus width varying along L) — US 6,309,053 (Torgerson & Hurst, filed 2000‑07‑24) discloses precisely this, but it is commonly owned; see §6.
• 20 (drain/source electrodes and contacts; drain regions configured to set Ron) — the structural realization of '489's geometry teaching; conventional MOSFET source/drain design.
• 21 (elongated drain regions with a continuously non-contacted segment of selected length) — the crux. This is a resistance deliberately placed in series with the transistor's drain, i.e., a distributed ballast. '341 teaches a ballast resistor whose value is chosen as a function of the power-trace parasitic resistance, and drain/source ballasting by un-contacted or lightly contacted diffusion/polysilicon extensions was routine power-MOSFET design. The '917's own stated benefit — the drain electrode "does not need to extend over such continuously non-contacted drain finger sections," freeing lateral space for a wider ground bus — is a layout-efficiency design incentive of exactly the kind KSR credits. This is the claim with the best non-obviousness argument, but I judge it more likely than not obvious over '341 + '489.

5. Rebuttal space (where the combination is attackable)

1. Kodak '203 compensates in the time/digital domain, not by device physics. It adjusts pulse counts, and even observes that "Head voltage variations … entail considerable hardware cost increases" — an argument that it points away from a hardware (FET-Ron) solution. Counter: '341 supplies the hardware solution in the same art, and '489 supplies the cost-reduction rationale, so there is no true teaching away.
2. '489 is a non-monolithic thermal head (driver ICs mounted on an alumina head) with much lower heater resistance (8–10 Ω ballpark) than '917's ≥ 100 Ω; '341 for its part discloses discrete ballast resistors, not FETs whose own on-resistance is tuned, and its exemplary heaters are ~8–10 Ω. Counter: the technique (set driver/ballast resistance as a function of bus parasitic resistance; raise heater resistance when driver Ron is low) transfers directly; the base printhead structure comes from '477/'262.
3. Claim-construction tension in claim 1. Because '917 deliberately increases the effective on-resistance of interior FETs (via longer non-contacted drain segments), the "each FET … Ron < 250,000 Ω·µm²/A" cap and the "configured to compensate" element pull in opposite directions. A challenger should probe whether every FET in an operative 100+-generator array can satisfy both; this is simultaneously an enablement/§ 112 issue and a reason the numeric limit may not distinguish over art showing a typical FET in that range.
4. Certificate of correction (2003‑02‑18). Any challenge must verify the operative claim text post-correction.

6. Double-patenting note (distinct from § 103)

US 6,309,053 ("ground bus that overlaps transistor active regions"; Torgerson + Hurst; filed 2000‑07‑24, granted 2001‑10‑30) and the '917 share an inventor and an owner. It is likely disqualified as § 103 art by pre-AIA § 103(c), but because it is commonly owned and not "same invention," it is a candidate for obviousness-type double patenting against at least claims 8–9 (and 6–7 by extension). The same analysis applies to the commonly owned US 6,523,935 (Narrow ink jet printhead) and US 6,422,676 (Compact ink jet printhead).

7. Conclusion and confidence

• Claim 1: Obvious over US 5,144,341 + US 5,469,203 + US 5,272,489, and alternatively over US 4,719,477 (or US 4,345,262) + US 5,469,203 + US 5,272,489. The motivation is supplied by (i) the identical, expressly recognized uniformity problem in a thermal ink jet head ('341, '203), (ii) the known technique of tuning series resistance as a function of power-trace parasitic resistance ('341's ballast resistors), and (iii) the known technique of sizing a driver element to set on-resistance and of raising heater resistance when driver Ron is low ('489). Confidence: high.
• Claims 2–5, 10–20: More likely than not obvious; strongest on '341 + '203 + '489. Confidence: moderate-to-high. (Claims 6–9 hinge on commonly owned art — treat via § 103(c)/ODP, not § 103.)
• Claim 21: Best non-obviousness candidate, but I read the non-contacted drain segment as distributed ballasting, which '341 + '489 + routine power-MOSFET practice would render obvious to try. Confidence: moderate.
• Verification caveats: I did not retrieve full text of US 4,719,477, US 4,345,262, US 5,317,346, US 5,638,101, DE 2,945,658, or EP 1,563,998; characterizations of those rest on titles and the '917 specification's own citations (which, for '477/'346, I treat as binding admissions). US 6,412,917's status as a § 102/103 reference in Canon v. Slingshot, IPR2023-00313 (petition materials at ptacts.uspto.gov, petition 1550157) is confirmed and corroborates that a PHOSITA treated this disclosure as 2001-era background art — I cite it as context, not as record prior art. The ITC record (Pub. 4373) confirms the '917 was asserted but withdrawn in 337‑TA‑723; I would not read commercial-success or validity significance into that withdrawal without nexus evidence.