US 7080819

I'll search for the patent to confirm the bibliographic record, then summarize.

US Patent 7,080,819 — Analyst Summary

Searches run: Google Patents / Justia / FreePatentsOnline full-text records for "US7080819B2" and the application publication; a targeted query for CAFC 2026 dockets citing "7080819" / "7,080,819". The full text provided in the task packet was used as the authoritative source and it matches the live records retrieved.

1. Bibliographic record

Prior art cited on the face: US 4,830,286 (Bosch); US 5,636,615 (Diesel Technology); US 5,820,101 (Elasis/Fiat); US 6,126,094 (Elasis/Fiat).

2. Abstract (verbatim)

"A fuel injection valve includes a solenoid, which is filled with low-pressure oil. The solenoid receives a biasing means and a movable member. The movable member is actuated by the biasing means and magnetic force generated by the solenoid. The movable member includes a flat-plate portion that contacts with the solenoid and departs from the solenoid. The outer circumferential periphery of the flat-plate portion has multiple notches, through which low-pressure fuel flows into to the upper side of the flat-plate portion that has an oil passage groove, through which a center portion of flat-plate portion communicates with the outer circumferential portion of flat-plate portion. Each notch has a deepest portion that is radially most recessed from the outer circumferential periphery of the flat-plate portion. The oil passage groove is apart from a deepest portion of the notches."

3. Plain-language overview of the independent claim

Important correction to a premise in the request: there is only one independent claim in this patent — claim 1. Claims 9, 12, 13 and 14 are dependent on claim 1 (each opens "The fuel injection valve according to claim 1, wherein…"), and claims 2–8 and 15–18 depend from those. So the "each independent claim" wording is inapposite here.

Claim 1 — plain language

A common-rail diesel fuel injector whose solenoid valve contains a spring-loaded armature ("movable member"). The armature has a flat disc (the "flat-plate portion") whose upper face is the attracted face that slaps against the solenoid when energized and moves away when de-energized (or vice versa depending on which force is acting). Three things define the claim:

1. Notches on the disc's outer rim — low-pressure fuel flows through these into the gap between the solenoid and the attracted face.
2. An oil passage groove formed in the attracted face — it lets low-pressure fuel travel between the center of the face and the outer circumferential portion of the face (i.e., it channels damping fluid in/out so the armature can move fast).
3. The groove stops short of the notch's deepest point — the oil passage groove is apart from the deepest, radially most-recessed portion of the notch. That is the point of novelty: the deepest point of the notch (a stress riser) is not cut into/hollowed out by the groove, so impact-induced stress does not concentrate there and the armature survives millions of impact cycles.

Why it matters (the patent's own data, FIG. 6): maximum principal stress at the notch deepest point —

• Conventional member 5J (60° notch, 0.9 mm deep, groove joins the deepest point): 184 MPa
• Modified member 5H (90° notch, 2.0 mm deep, groove still joins the deepest point): 120 MPa
• The claimed member 5 (90° notch, 2.0 mm deep, groove staggered away from the deepest point): 86 MPa

So the claim is essentially "keep the fluid channel but move it off the stress riser."

Numeric ranges taught in the description / dependent claims (not in claim 1 itself): notch opening angle ≥ 45°, preferably ≥ 90° (claim 12); radial distance from the deepest portion to the contacting face ≥ 1.0 mm, preferably ≥ 2.0 mm (claim 13). Six oil passage grooves at 60° spacing staggered 30° from three notches spaced 120° apart (claims 3, 4, 8); auxiliary grooves of shorter radial length than the oil grooves (claims 6, 7); bimetallic construction — cast shaft + annular silicon-steel plate joined by sintering or friction pressure welding (claims 9-11, 16-17).

Second embodiment captured by dependent claim 14

Rather than an inner-cylinder stopper face (claim 3), the outer cylinder of the solenoid has an annular stopper face 3S, and the corresponding annular contacting face is on the outer periphery of the attracted face, with radial oil passage grooves crossing it. This gives a larger contact area (more stable armature seating) and permits wider grooves for faster oil flow. Claim 14 is, again, dependent on claim 1 — it incorporates claim 1's "groove apart from the notch deepest portion" limitation.

4. Litigation / CAFC check — explicit uncertainty

I did not find any authoritative evidence of a Court of Appeals for the Federal Circuit 2026 docket, appeal, IPR appeal, or any district-court action involving US 7,080,819. Nothing in the retrieved records (Google Patents, Justia, FreePatentsOnline) shows a litigation or PTAB proceeding for this patent; the record is only the ordinary prosecution and maintenance-fee history. I cannot query PACER or the CAFC docket system directly from this environment, so I am stating this as absence of evidence, not proof of absence. If you need a definitive answer, the check should be run against PACER/CM-ECF and the CAFC's docket search, or via a litigation database (Lex Machina, Docket Navigator, Unified Patents).

One identifier caution: the bare number 7080819 is not unique across the world. There is a separate, unrelated Japanese patent numbered JP 特許第7080819号 (P7080819), granted 2022-06-06 to Cell Medica Switzerland AG, titled "結合メンバー / PD-L1 binding member" (PCT/EP2017/054367, EP priority 16020057.2). That is a biotechnology patent with no relationship to the Denso fuel-injection patent. I have not merged or corrected them; I flag it only so that any search on the plain number "7080819" is not polluted.

5. Sources

• Google Patents full text: https://patents.google.com/patent/US7080819/en
• Pre-grant publication (Justia): https://patents.justia.com/patent/20050139798
• FreePatentsOnline: https://www.freepatentsonline.com/y2005/0139798.html
• Japanese family member JP 4026592 B2: https://patents.google.com/patent/JP4026592B2/en
• Unrelated JP 7080819 (PD-L1 binding member): https://patentimages.storage.googleapis.com/a1/bf/09/9c5ca8d2418c8d/JP7080819B2.pdf

Note on status: the "Expired – Lifetime / adjusted expiration 2025-02-01" entry carries Google's own disclaimer that it is an assumption, not a legal conclusion. Treat the expiration date as unverified unless confirmed against USPTO PatentCenter's maintenance-fee and term-adjustment data.

I'll research litigation involving US patent 7080819. Let me run several targeted searches.

The initial results are dominated by unrelated "819" patents. Let me run more precise searches targeting US 7,080,819 specifically.

Let me run additional targeted queries, including on litigation databases and for Denso enforcement.

Findings: Litigation involving U.S. Patent No. 7,080,819

Bottom line: I found no litigation involving U.S. Patent No. 7,080,819. Based on the searches I was able to complete, there is no known district court case, ITC Section 337 investigation, or PTAB proceeding asserting or challenging this specific patent.

Important caveat on the search results

A large number of hits came back for other patents that merely end in "819" — none of which is the patent you asked about. Per the operating rule to interpret identifiers literally and not auto-correct, I am flagging these explicitly as unrelated, so they are not mistaken for 7,080,819:

None of these involve Denso or the fuel-injection-valve technology of 7,080,819.

About the patent itself (for context)

• Patent: US 7,080,819 B2, "Fuel injection valve having internal oil groove"
• Assignee: Denso Corporation (Kariya, JP)
• Inventor: Senta Tojo
• Priority date: 2003-12-24; Filed: 2004-12-15; Granted: 2006-07-25
• Status: Expired – Lifetime; adjusted expiration 2025-02-01
• Family: JP 4026592B2, CN 100340762C, DE 102004062188B4, FR 2866075B1

The Google Patents record for this patent shows no litigation section — it lists only prior-art citations (e.g., US 4,830,286 Bosch; US 5,636,615; US 5,820,101; US 6,126,094) and forward citations from later Denso/Bosch/Continental patents (e.g., US 7,571,891; US 8,684,286). Those are patent-to-patent citations, not lawsuits.

Status of my verification (honest limitations)

I was cut off by a tool/step limit before I could exhaustively query the specialized litigation sources you named:

• The Unified Patents litigation portal (portal.unifiedpatents.com/litigation/caselist?patents=7080819) — I attempted this but the query returned generic Unified Patents IPR material rather than a case list for this patent, and I could not complete a second run.
• CourtListener / PACER and CAFC docket searches for the exact string "7,080,819" — my queries returned only false positives for other "819" patents; I could not run a clean, dedicated docket search before hitting the limit.
• I found no Denso-initiated enforcement action against any named defendant that references this patent.

Recommendation

Because the searches were inconclusive rather than confirmatorily negative, treat this as "no litigation found" rather than an absolute "none exists." To close the gap with high confidence, the following should be run directly:

1. https://portal.unifiedpatents.com/litigation/caselist?patents=7080819
2. CourtListener RECAP docket search: "7,080,819" (exact string), and CAFC docket search for the same.
3. A Denso Corporation party-name search in PACER (Denso is a large portfolio holder that typically resolves matters through cross-licensing rather than litigation, which is consistent with finding nothing).

If you'd like, I can retry the Unified Patents portal and CourtListener searches specifically for the exact string once tool access is available.

Caveat: Nothing here is legal advice, and this is not a legal conclusion; it is a records search summary as of the date of the search.

I'll verify the structured data against live sources before writing anything.

Nothing surfaced. Let me run more targeted checks (PTAB docket patterns, litigation assertion, and any Unified Patents activity).

Let me do a final set of checks specific to AIA proceeding dockets and expiration status.

Proceedings overview

Zero AIA trial proceedings. The canonical structured feed ("PTAB proceedings on file") returns no IPR, PGR, or CBM for US 7,080,819, and my independent web checks (which surfaced PTAB petition documents, PTAB FWD excerpts, and Denso-related litigation material, but nothing naming this patent) turned up no proceeding either. Breakdown by status: active 0 / claims invalidated 0 / claims sustained 0 / settled 0 / institution denied 0. All 18 claims are untested at the Board.

The bottom line for a defendant is not "the patent survived IPRs and is hardened" and not "the claims are dead at the PTAB" — it is that the patent itself is expired. Google Patents records the legal status as "Expired - Lifetime," with an adjusted expiration of 2025-02-01, and the last maintenance fee shown is the 12-year payment on 2018-01-15 (event code M1553). As of today (2026-09-30), there is no live claim to infringe going forward, so the practical exposure is at most a closed historical window, not an IPR fight. See https://patents.google.com/patent/US7080819/en.

One caveat on method: the ODP feed is the authoritative list and it is empty, but I could not run a direct PTAB E2E docket query for this patent — my searches returned third-party petition documents rather than a docket page. If you need a belt-and-suspenders confirmation, search "7,080,819" (and "7080819") at https://ptacts.uspto.gov/ptabweb/ and check the Patent Center transaction history at https://patentcenter.uspto.gov.

Proceedings

None. There is nothing to list. No proceeding number exists for this patent, and I will not generate one.

For completeness, the "near-miss" hits my searches produced are all unrelated: PTAB petitions in Lionra v. Fortinet (US 8,787,060 / the '708 patent — a different patent whose number coincidentally ends in 708), IPR2025-01089 (a piston-geometry patent), IPR2024-01110 (Facet/Mobileye), and the Denso fuel-pump and fuel-injection-systems antitrust/consumer class actions (E.D. Mich., E.D.N.Y., Québec). None of these involves US 7,080,819. The only recent third-party document I saw touching this family is a citation by US 2024/0254954 A1 (Mitsubishi Heavy Industries Engine & Turbocharger, priority 2021-07-27) — a citation, not a challenge.

Strategic summary

Claim status. All 18 claims are UNTESTED. No claim of 7,080,819 has ever been canceled, confirmed, or construed by the PTAB. The claim set has two independent claims: claim 1 (the base fuel-injection-valve claim reciting the notched flat-plate portion and the oil passage groove "apart from the deepest portion of the notch") and claim 14 (the second-embodiment claim reciting the annular stopper face on the solenoid's outer circumferential periphery and an intermittently annular contacting face crossed by the oil passage groove). Claims 2–13 depend from claim 1; claims 15–18 depend from claim 14. The asserted-invention core — the off-axis oil passage groove that avoids hollowing the notch's deepest portion, with the specification's comparative stress figures (184 MPa → 120 MPa → 86 MPa maximum principal stress) — remains as issued, subject only to whatever prosecution history and any certificates of correction or reexamination exist (none are flagged in the structured data).

Estoppel landscape. There is no § 315(e)(2) estoppel on anyone, because no IPR ever reached a final written decision. No petitioner, real party in interest, or privy is barred from raising § 102 or § 103 grounds based on patents or printed publications; no Sotera-type stipulation or Fintiv record exists. That said, the important gate is statutory availability, not estoppel: PGR is unavailable (the application was filed 2004-12-15, before the 2013-03-16 AIA cutoff; PGR also had a 9-month window that closed in 2007), and CBM is unavailable (this is a fuel-injector mechanical valve, not a "covered business method" — and in any event CBM has sunset). IPR would remain formally available because IPR has no filing-date restriction and expired patents can still be reviewed for the period in which they were in force — but with expiration on 2025-02-01, any IPR would be an academic exercise unless there is a live back-damages dispute covering pre-2025 conduct. For a district court defense, the four references cited on the face of the patent are US 4,830,286 (Bosch), US 5,636,615 (Diesel Technology), US 5,820,101 and US 6,126,094 (both Elasis/Fiat) — all still usable as § 102/§ 103 art with no estoppel taint.

Pattern signals. No pattern exists on this patent: no repeat petitioner, no joinder, no Unified Patents or other defensive aggregator in the chain, no Director Review, no Federal Circuit appeal. The patent owner (Denso Corporation, assignee from the 2004-12-15 assignment of Senta Tojo's invention per reel/frame 016104/0679) has never had to defend these claims at the Board, and has therefore never been perceived as a PTAB aggressor or target on this asset. The family did issue broadly — JP 4026592 B2, CN 100340762 C, DE 102004062188 B4, FR 2866075 B1 — which is the profile of a product-protection filing by an operating automotive supplier rather than a monetization vehicle. That reinforces the read that 7,080,819 was never asserted, and never needed to be defended.

Recommended next steps

• Lead with expiration, not invalidity. Before briefing any PTAB or district court defense, confirm the 2025-02-01 expiration in USPTO Patent Center (https://patentcenter.uspto.gov) and pull the maintenance-fee and term-adjustment history. If the patent lapsed on 2025-02-01 at end of term, there is no prospective infringement and an IPR would be a poor use of budget; the defense is "expired, no prospective relief."
• If a demand letter or complaint cites this patent, demand the accrual dates. Only pre-2025-02-01 conduct could support damages, and § 286 limits recovery to six years before suit — so a 2026 filing touching conduct from roughly 2020 onward is a narrow, shrinking window. Run the numbers before conceding anything about validity.
• Do not over-credit the patent's durability. The absence of PTAB activity here is not evidence that the claims are strong; it is consistent with a product-protection patent that nobody ever needed to knock out, and with a patent that has now expired. Treat "no IPRs" and "hardened claims" as different things.
• Verify the docket directly. Since the ODP feed is empty and my search pass was indirect, a five-minute search of "7,080,819" on PTAB E2E (https://ptacts.uspto.gov/ptabweb/) and on CourtListener (https://www.courtlistener.com) will close the loop on both PTAB filings and any district court/Federal Circuit activity. If anything appears, note that any § 315(b) one-year bar clock runs from service of a complaint alleging infringement of this patent.
• If a proceeding does surface that my pass missed, the deliverables that matter are the institution decision (which grounds were instituted, and the Fintiv/§ 325(d) reasoning) and the FWD's claim-by-claim dispositions — and I would quote the FWD's claim numbers verbatim rather than paraphrase. I will not characterize an FWD I have not read.

I'll start by verifying the assignment record and cross-referencing sources.

Let me check for litigation involving this patent and confirm Denso's corporate status.

Let me verify whether this patent has ever been asserted and confirm Denso's operating status.

Ownership Analysis: US 7,080,819 B2 — "Fuel injection valve having internal oil groove"

Data limitation flag: The fetched Google Patents record exposes only the USPTO assignment-cover-sheet metadata (reel/frame, assignor, assignee, execution date, recording date). It does not expose the correspondent-of-record field, and I could not retrieve a live Assignment Center abstract page for this patent within this session. Where a field is unavailable I say so rather than infer it.

Inventors

• Single-inventor patent. No co-inventors, so the "all inventors depart before a fire-sale" pattern is not applicable in the multi-inventor sense.
• No departures are reflected in any recording. The only recorded instrument is the inventor's own assignment to DENSO (executed 2004-11-29, i.e., 25 days before the JP priority filing of 2003-12-24 — actually executed after priority but before the US filing of 2004-12-15). There is no recorded assignment away from DENSO, so no inventor-exodus evidence exists. The inventor's name also recurs on a later, separate DENSO family member (US 2009/0241905, assigned to DENSO Corporation + Nippon Soken), which is consistent with Tojo remaining a DENSO-side engineer — i.e., no departure signal.

Original assignee

• DENSO Corporation (Kariya-city, Aichi-pref., Japan) — named both as original assignee on the issued patent and as assignee on the single recorded assignment (Reel 016104 / Frame 0679). Google Patents "Current Assignee: Denso Corp"; the record shows no subsequent change.
• Primary line of business: tier-one automotive supplier — fuel-injection systems, common-rail diesel injection components, thermal, powertrain electronics, semiconductor sensors. This patent is squarely a core-product patent (a common-rail solenoid control valve), not a speculative filing.
• Did they ship a product embodying the claims? Strongly supported but not directly proven from the fetched text. The patent is a component-level improvement to DENSO's common-rail injector solenoid valve (movable member / armature plate), which is DENSO's flagship diesel product line; DENSO is a major common-rail supplier. I have not located a product teardown or DENSO catalog page in this session confirming a specific part number, so I qualify this as high-confidence-but-not-verified.
• Current status: Operating. DENSO Corporation is a listed, ongoing Japanese multinational (Tokyo Stock Exchange). No bankruptcy, no dissolution. It appears in unrelated litigation as a defendant (Broadcom ITC Inv. 337-TA-1119; the ignition-coil antitrust settlements) — i.e., it is an active operating participant, not an NPE.

Assignment timeline

One recorded assignment only. The USPTO assignment record for US 7,080,819 consists of a single instrument, and Google Patents' Legal Events table shows nothing but the fee/grant events afterward (see below for why that is decisive).

• 2004-11-29 (executed) / recorded 2004-12-15 — Reel 016104 / Frame 0679
  • Conveyance: Assignment (Assignment of Assignors' Interest)
  • Assignor: TOJO, SENTA (individual inventor)
  • Assignee: DENSO CORPORATION (Kariya, Japan)
  • Correspondent: Not exposed in the source data. Google Patents shows only the free-format text "ASSIGNMENT OF ASSIGNOR'S INTEREST" with the reel/frame; the recording correspondent field is not published in the fetched record. I will not guess it. (For verification, the Assignment Center abstract for reel 016104/frame 0679 would display it.)
  • Context: Routine inventor-to-employer assignment executed as a filing formality, four days before the JP priority anniversary and on the same day-ish as the US filing (2004-12-15). Not a sale, not a reorg.

Everything after that is fee maintenance, not conveyance. Google Patents' Legal Events list for this patent contains only:

• 2006-07-05 — patent grant
• 2009-12-23 — 4th-year maintenance fee
• 2012-12-04 — fee-payment procedure (payor number assignment to owner as large entity)
• 2014-01-17 — 8th-year maintenance fee
• 2018-01-15 — 12th-year maintenance fee (large entity)

There is no security agreement, merger, change of name, license, release, correction, or transfer-to-asserter anywhere in the record. The patent's legal-status line reads "Expired – Lifetime, expires 2025-02-01," and the "Adjusted expiration 2025-02-01" entry is a term-adjustment/expiry date, not an assignment.

Timeline diagram

timeline
    title Ownership of US 7080819
    2003 : JP priority filed by Denso
    2004 : Inventor assigns to Denso
         : US application filed
    2006 : Patent issued to Denso
    2009 : First maintenance fee paid
    2014 : Second maintenance fee paid
    2018 : Third maintenance fee paid
    2025 : Patent expires

NPE / troll-pattern signals

1. Shell-entity transfer — NOT PRESENT. No assignment to any "IP / Patents / Licensing / Holdings / Ventures" entity exists. The chain terminates at DENSO Corporation, an operating manufacturer. Reel 016104/0679 (2004-12-15) is the only recorded instrument and runs to the operating company.

2. Known asserter in the chain — NOT PRESENT. The only assignee is DENSO Corporation. I checked the fetched "Cited By" and "Families Citing" sets: the citing entities (Bosch, Caterpillar, Continental, Delphi/PHINIA, Cummins, Mitsubishi Heavy Industries, Neology) are either operating companies or, in Neology's case, an RFID vendor asserting its own unrelated patents. No assignee in the US 7,080,819 chain matches Acacia, Marathon, IV, IPNav, Wi-LAN, Conversant/Mosaid, Vringo, Pendrell, Innovatio, MPHJ, Lumen View, Round Rock, Document Generation Corp, or an Erich Spangenberg entity.

3. Repeat correspondent across the chain — NOT PRESENT (unable to assess more than one link). With a single-link chain there is no recurrence to test, and the correspondent field is not exposed in the fetched data. Nothing to flag.

4. Cascading transfers — NOT PRESENT. One transfer total (inventor → DENSO) over the entire 21-year life of the patent. Zero chained LLCs.

5. Pre-litigation transfer — NOT PRESENT. I found no infringement suit, ITC complaint, or PTAB proceeding naming US 7,080,819. The "819 patent" hits in my searches are a different patent — US 7,706,819 ("Mixed-Mode Interaction," Aeritas, NFCU) and Neology's own '819 — neither of which is this patent. There is no litigation to be "preceded" by.

6. Bankruptcy fire-sale — NOT PRESENT. DENSO never filed Chapter 7/11; no patent-sale proceeding exists.

7. Privateering — NOT PRESENT. No transfer to any asserting entity, so DENSO cannot be "asserting through" one.

8. Defensive aggregator (anti-NPE) — NOT PRESENT. No RPX/AST/LOT/Unified/OIN acquisition. (Not needed here: the patent never left the operating company, so it did not require neutralization.)

Verdict

Insufficient data — but with an affirmative reading: the chain never left the operating company.

The USPTO record for US 7,080,819 contains exactly one instrument — the inventor's assignment to DENSO Corporation, executed 2004-11-29 and recorded 2004-12-15 at Reel 016104 / Frame 0679 — and Google Patents' legal-event table shows only grant and maintenance-fee entries thereafter (2006, 2009, 2014, 2018), with an expiration entry on 2025-02-01. No shell entity, no known asserter, no cascading LLC chain, no pre-litigation transfer, and no litigation or ITC/PTAB activity involving this patent were found. Under the taxonomy, a chain that terminates at a solvent operating manufacturer with zero post-issuance transfers is the non-NPE baseline, which the rubric maps to "Insufficient data (only the original assignment)" rather than to any NPE category.

Verify at: https://assignmentcenter.uspto.gov/ — search patent number 7080819 and cross-check reel 016104 / frame 0679 (the correspondent-of-record field, which I could not retrieve here, will be visible there).

I'll research the patent's cited references directly to build the anticipation analysis.

Let me pull deeper detail on the two most structurally relevant references.

Prior-Art Analysis — US 7,080,819 B2

Search basis: the four references appearing in the "Patent Citations (4)" block of the Google Patents record for US 7,080,819 (i.e., the references cited by the examiner on the face of the patent), retrieved and verified against Google Patents / Espacenet / FreePatentsOnline full texts. This builds on the earlier summary (one independent claim — claim 1; claims 2–18 all dependent).

Preliminary point on § 102 dates

US 7,080,819's application (US 11/011,371) was filed 2004-12-15 with foreign priority to JP 2003-426271 (2003-12-24). This is a pre-AIA application, so pre-AIA § 102 governs. The § 102(b) critical date is one year before the U.S. filing date → 2003-12-15 (foreign priority does not move the § 102(b) bar date). All four cited references issued between 1989 and 2000, so all four independently qualify as § 102(b) statutory-bar prior art — they are prior art as a matter of law regardless of the JP priority claim.

However, and this is the key analytical point: none of the four references anticipates any claim of US 7,080,819 under § 102. Each is missing at least the single limitation that gives the patent its point of novelty — "the oil passage groove is apart from the deepest portion of the notch" (claim 1, final element; see also claim 3's "circumferentially between angular positions of the outer end portions"). All four are properly characterized as § 103(a) background/combinable art, not anticipatory art. Details below.

1. US 4,830,286

Description (from the granted claim 1): An electromagnetically actuatable valve for fuel-injection systems comprising a ferromagnetic valve housing, a valve seat, a valve closing element, a magnetic coil, and a flat armature arranged to engage the valve seat. The flat armature is "configured in the manner of a gear wheel having a plurality of radially protruding teeth spaced uniformly apart from one another," and each tooth carries stop lobes on its surface remote from the valve-closing element, which rest on a stop face when the armature is excited by the coil.

Element mapping to claim 1:

§ 102 conclusion: Does not anticipate claim 1 (missing the attracted-face oil passage groove, and a fortiori its spacing from the deepest portion), and therefore cannot anticipate any of claims 2–18, all of which incorporate claim 1. Most relevant to: the concept of a toothed/notched flat armature whose periphery defines fuel-flow passages and whose face bottoms out on a fixed stop face — i.e., it is the closest art for the "notches in the outer circumferential periphery of the flat-plate portion" element of claim 1.

2. US 5,636,615

Description: A unit pump/injector having a pump chamber and a solenoid-actuated control valve whose armature is a flat plate secured to the control valve by a flatheaded countersunk screw. The armature resides in a fuel-filled armature cavity and is electromagnetically cycled between closed and open positions. The flat armature plate is formed with through-holes and/or slots and, per claim 5, a "fuel flow channel of generally rectangular cross-section extending across the armature plate surface exposed to the electromagnetic stator from at least one edge thereof to said at least one fuel pressure equalization port, whereby fuel flow through the armature is facilitated." Claim 7/8 recite that the channel depth is about one-quarter the armature plate thickness; claim 10 recites that slots extend radially from adjacent the screw counterbore to the outer edges of the plate. The stated purposes are to prevent cavitation erosion of the armature/screw and to improve hysteresis.

Element mapping to claim 1:

§ 102 conclusion: This is the closest single reference to the core fluid-flow concept of claim 1 (a groove formed in the stator-facing armature face that ducts oil between the plate's outer portion and its center). It still does not anticipate claim 1, because it does not disclose the claim-1 combination of (i) peripheral notches each having a radially deepest portion, and (ii) the groove being apart from that deepest portion. Absent that limitation, no dependent claim is anticipated either. Best use: primary § 103(a) reference against claim 1 in combination with US 4,830,286 (which supplies the notched flat armature) — though the resulting combination does not reach the "groove off the stress riser" limitation that the patent itself relies on for patentability.

3. US 5,820,101

Description: A metering valve for a common-rail fuel injector having a shutter for the discharge conduit of a control chamber, a first spring acting on an intermediate element to hold the shutter closed, and an electromagnet actuating an armature that is disconnected from the intermediate element/stem, held resting against it by a second spring preloaded between the armature and the intermediate element so as not to affect the first spring. The express objective is reducing armature rebound and permitting a short interval between successive armature movements (pre-injection). The armature is described as disk-shaped but its face geometry (notches, grooves) is not the subject of the disclosure.

§ 102 conclusion: Does not anticipate claim 1 or any dependent claim. It discloses the injector context (electromagnet, disk armature, spring biasing, control chamber/discharge conduit) but is silent on notches in the flat-plate periphery and on any attracted-face oil passage groove, let alone their spatial relationship. Best use: general background § 102(a)/(b) art showing a solenoid-operated metering valve/armature in a fuel injector; not a serious anticipation candidate for any claim.

4. US 6,126,094

Description: An injector with a hollow body, a metering valve, and an electromagnet activating an armature controlling the valve, with the electromagnet housed in a one-piece jacket having an integral end wall, and a spacer between the guide member and the electromagnet to set the air gap. Notably, the armature 27 is a disk 37 that "comprises a number of sectors 38, e.g. three (FIG. 3), separated by openings 39 through which discharge chamber 20 communicates with central hole 31 of core 28."

Element mapping to claim 1: The three-sector, three-opening disk armature is superficially the closest thing in the cited art to the patent's three V-shaped notches spaced 120° apart in the flat-plate periphery, and the openings do provide a fuel-flow path across the plate. But:

• The openings are described as through-openings between discrete sectors, not as peripheral notches each having a "deepest portion" radially most recessed from the plate rim.
• There is no disclosure of an oil passage groove defined in the attracted face connecting the face center to the face's outer circumferential portion at all, and therefore no disclosure that such a groove is apart from a notch's deepest portion. The focus of the reference is the jacket/spacer construction, not armature face hydraulics.

§ 102 conclusion: Does not anticipate claim 1 or any dependent claim. Best use: secondary § 103(a) art showing a multi-sector disk armature with intervening flow openings in a fuel injector — combinable with US 5,636,615.

Consolidated result

Bottom line: For all four face-cited references, the answer to "which claim(s) does it potentially anticipate under § 102" is no claim — neither independent claim 1 nor any of dependent claims 2–18. The claim-1 limitation "the oil passage groove is apart from the deepest portion of the notch" is the distinguishing feature, and none of the four references discloses it (or even the underlying "groove in the attracted face" element in the spatial arrangement claimed). The references are appropriately treated as § 103(a) art, with the strongest two-reference combination being US 4,830,286 + US 5,636,615.

Additional citations worth noting (not examiner-cited § 102 art)

Two other citation groups appear on the record and are worth flagging for completeness, though they are not the § 102 face citations:

• Family/foreign search-report cites (3): IT 212428 Z2 (Weber S.r.l., 1989); DE 10018304 A1 (Robert Bosch GmbH, 2001-10-25 — "Armature plate of a switching magnet … and method for producing such an armature plate"); JP 3633885 B2 (Denso, 2005-03-30 — "Electromagnetic valve device and fuel injection device using the same"). DE 10018304 A1 is a plausible additional § 102(b)/§ 103 armature-plate reference and should be pulled in full if a validity opinion is being prepared.
• "Cited By" art (e.g., US 2007/0057218 A1 → US 7,571,891 B2, Denso "Solenoid valve," 2009; US 2009/0107463 A1, Denso "Fuel injection valve," 2009) is all post-dating the 2003 priority and is therefore not prior art to US 7,080,819 — relevant only as evidence of the field or for later-family analysis.

Uncertainty flagged: I did not retrieve the full text of US 4,830,286's drawings or of the DE/JP family cites within this session; the US 4,830,286 and US 5,820,101 mappings above rely on the granted claim text and abstracts as retrieved, not on a figure-by-figure comparison. If the goal is a formal invalidity contention, those two documents should be read in full against FIG. 3–5 of the patent.

Sources: Google Patents US7080819B2 (https://patents.google.com/patent/US7080819/en); Espacenet claim text for US4830286A; Google Patents US5636615A; Google Patents US5820101A; Google Patents US6126094A; FreePatentsOnline US6126094.

I'll ground the obviousness analysis by pulling the disclosures of the prior-art references identified on the patent's front page and in its family citations.

Now let me check the remaining cited references and the art relevant to the dependent claims (armature-plate-to-shaft joining, and directional-flow grooves in an armature face).

Obviousness Analysis — US 7,080,819 B2 under 35 U.S.C. § 103

Building on the prior section: that section established the bibliographic record, confirmed there is a single independent claim (claim 1) with claims 2–18 all dependent, and found no litigation/PTAB/CAFC record. No contradictions with this source set were found. This section assumes the reader has the claim text and the FIG. 6 stress table (184 / 120 / 86 MPa) from that prior section and does not repeat them.

Standing caveats. This is a technical, not legal, opinion. The patent is expired (§ 103 has no prospective reach except as a validity defence to past damages or in a reexamination-type reconstruction), and Google's own status disclaimer on the family applies. Where I could not verify a reference's disclosure from primary text, I say so explicitly rather than inferring it.

1. The legal framework actually being applied

Under Graham v. John Deere Co., 383 U.S. 1 (1966), and KSR Int'l Co. v. Teleflex Inc., 550 U.S. 398 (2007):

1. Determine the scope and content of the prior art.
2. Ascertain the differences between the prior art and the claims.
3. Resolve the level of ordinary skill.
4. Assess objective (secondary) indicia — unexpected results, teaching away, long-felt need, commercial success.

KSR additionally licenses: (a) combining prior-art elements according to known methods to yield predictable results; (b) "a finite number of identified, predictable solutions" to a known problem; (c) design incentives flowing from the recognition of a problem; and (d) the general rule from In re Aller that discovering optimum or workable ranges of a disclosed variable by routine experimentation is not inventive.

2. The prior art on the face of the patent and in the family (the "Prior Art section")

Supplementary (cited-by art, not cited against the patent): US 6,036,460 (Christ; PDF) — a one-piece armature with slots at the middle-beam/outer-body interface, expressly for damping armature motion; and US 2008/0116405 A1 → US 7,819,379 (Bosch) on attaching an armature plate to a valve needle.

Critical point on the "prior art": the specification's own Background is statutory prior art against the claims under the applicant-admitted-prior-art doctrine (MPEP § 2129; In re Fringer, 207 F.2d 1136 (CCPA 1953)). The patent expressly admits that members 5J and 5H are "conventional"/modified prior structures, and FIG. 6 is captioned as a comparison against them. That admission supplies virtually the entire claim 1 apparatus, as set out next.

3. Element-by-element: claim 1 vs. the admitted prior art

Result: claim 1 differs from the admitted prior art by exactly one thing — the angular/positional relationship between the groove's outer terminus and the notch apex. This is a textbook KSR situation: the case turns almost entirely on (i) whether the problem was known, and (ii) whether the solution is a predictable design choice or an "arrangement of parts" change with no change in function.

Both answers favour obviousness:

• The problem was known and stated by the patentee itself. The Background identifies the very defect in 5H: "each oil passage groove 58 communicates with the deepest portion 5A, and stress is apt to be concentrated to the deepest portion 5A. Accordingly, structural strength may be decreased." That is a design incentive arising directly from the recognition of the problem (KSR factor (c)). Where the specification frames the invention as solving a problem it has itself articulated, the motivation prong is normally satisfied on the face of the reference.
• The solution changes no function. The groove's job is to let low-pressure fuel move between the center and the periphery of the attracted face. Relocating its outer terminus 30° in the circumferential direction performs that function identically; the patent claims no flow-rate improvement from the offset, and states only that the notch apex "is not hollowed by the oil passage grooves." A change in the angular position of a part that does not change what the part does is the classic In re Japikse / In re Harza "mere rearrangement of parts" fact pattern.

4. The three strongest § 103 combinations

Combination A — Admitted art (5J or 5H) alone, in view of the recognized stress-riser problem

References: the specification's own FIG. 6 members (AAPA), optionally corroborated by US 4,830,286.
Rationale: Stress concentration at a sharp re-entrant corner with a small curvature radius (the notch apex) is among the most elementary and well-known phenomena in mechanical design; the reference work of record, US 4,830,286, frames the whole armature-design exercise as a trade-off between "reduction in the armature mass and of the armature surface area that must be moved through the medium … while maintaining adequate rigidity." An ordinarily skilled artisan designing an armature that is "strongly impacted" (spec's own words) twice per injection cycle, and that will be further notched by a fluid groove, would as a matter of routine design avoid deepening the stress riser. There are, in KSR's words, "a finite number of identified, predictable solutions": either blunt the notch (5H's approach) or move the groove off the apex. The claim covers the second of these, chosen in preference to the first. This is the single most likely rejection to be written, and it does not require any secondary reference for the groove-per-se element because 5J/5H supply it.

Combination B — Admitted art + US 5,636,615 (Diesel Technology)

Rationale: US 5,636,615 supplies the missing design freedom element. Its claims 4–5 and the specification teach a "fuel flow channel … extending across the armature plate surface exposed to the electromagnetic stator from at least one edge thereof to said at least one fuel pressure equalization port," with depth "no more than about one-quarter the thickness of the armature plate," for the stated purposes of reducing "adverse hydraulic effects" and quickening "armature response time."
The teaching is that the face groove is a hydraulic expedient whose terminus at the plate edge is functional, whereas nothing about its angular registry with any particular peripheral feature is functional. Motivation to combine: both references are directed to the same problem — the fluid-filled armature cavity of a solenoid-actuated fuel control valve acting as a damper, and the need to move fluid fast enough to keep the armature responsive (the patent's own stated object: "produce a durable fuel injection valve that is capable of quickly moving"). One of ordinary skill would take the edge-to-center face channel of '615 and apply it to the Denso-type plate to preserve response, then place its outer terminus wherever the flow path is best hydraulically and structurally — i.e., off the apex. KSR ("a technique … used to improve one device, and a person of ordinary skill would recognize that it would improve similar devices in the same way").

Combination C — Admitted art + DE 100 18304 A1 (Bosch) [family-cited, and the closest structural reference]

Rationale: DE 100 18304 A1 is the most on-point structural reference in the record. It discloses (a) a circular disk-shaped plate part with radial recesses (36, 38), (b) grooved recesses opening into the region of the central guide bore, i.e. face grooves running from the outer radial recesses inward to the centre, (c) the express hydraulic rationale — the recesses "displace the medium" because "the switching operations in fuel injectors … run extremely fast," which is the same objective the '819 patent claims, and (d) tapering recesses ("tapering towards the centre"), which maps onto claim 2's "circumferential length [of the notch] … greater than a circumferential length of the deepest portion."
Motivation to combine: same field (common-rail injector armatures), same problem (fast fluid displacement from a magnetically-actuated armature plate), and the reference was known to the applicant (it appears in the family's citation list for the German, French and Chinese counterparts, and is cited on the Google record of JP 4026592 B2 and CN 100340762 C). If the Bosch grooved recesses open into the guide bore at an angular position that is not the apex of the radial recesses, Combination C is close to a § 102-grade disclosure of claim 1.
⚠ Verification gap: I retrieved only the English abstract and the EP 1 146 223 A2 abstract. Neither specifies the angular relationship between the "grooved recesses" and the apex of the "angled recesses (36, 38)". Before Combination C is relied on as a primary reference, the German full text and figures must be checked. I am flagging this rather than assuming it.

Secondary support for all three: US 6,126,094 supplies "disk 37 … three sectors 38 separated by openings 39," i.e. exactly the plurality of regularly-spaced peripheral flow notches of claim 1 in a disk-type armature, with the openings communicating to the core's central hole — and expressly for damping/rapid return.

5. Dependent claims — where they stand

6. Objective indicia and the counter-case

The patentee's best arguments, and my assessment:

1. Unexpected magnitude of the stress reduction. FIG. 6 does isolate the variable cleanly: 5H and claimed 5 share the 90° notch and the 2.0 mm radial distance, differing only in groove position — 120 MPa → 86 MPa, a 28.6 % reduction. That is a legitimate comparative showing and is not nothing.
   Assessment: moderate, and probably not enough. The reduction is a monotonic, directionally predictable consequence of removing a stress raiser from a notch root; there is no evidence the magnitude crosses the threshold that courts treat as "unexpected" (typically an order-of-magnitude or qualitative change, or a result the art would have predicted to fail). The patent also does not tie this datum to any claimed range — claims 1–18 are silent on MPa — so the showing is not coextensive with the claim scope.
2. Teaching away. The applicant could argue that the admitted "conventional" design deliberately connected the groove to the apex, and that the art therefore pointed away from the claim.
   Assessment: weak. Mere disclosure of a sub-optimal arrangement is not teaching away absent a criticism or disparagement that the claimed approach would not work. Here the criticism is the patentee's own Background — which cuts against the patentee, not for it.
3. Long-felt need / commercial success. Nothing in the record (no reissue, no litigation, no secondary-evidence citation) supplies either.
4. Claim-drafting gap the patentee could exploit. Claim 1's "apart from the deepest portion" is a negative positional limitation. If the examiner's combination places the groove on a sector-shaped notch's flank rather than its apex, claim 1 is met; if the reference's groove were merely shorter (terminating inside the plate before reaching the notch at all), a patentee might argue the reference's groove does not reach the "outer circumferential portion" as claimed. Combination B (US 5,636,615) is exposed to that argument because its channel runs edge-to-port; the examiner should therefore lead with Combination A (AAPA) or C (DE 100 18304), where the groove demonstrably terminates at the periphery.

7. Bottom line

• Claim 1 would very likely be held obvious. Its only point of novelty over the applicant's own admitted prior art (members 5J and 5H, FIG. 6) is one positional relationship, the problem to be solved was expressly recognized in the specification, and the solution is a change in the angular arrangement of a part with no change in the part's function or the system's objective. KSR + MPEP § 2129 (AAPA).
• Claims 2–8, 12–15 and 18 are obvious as design choices, optimizations of ranges disclosed in the admitted art, and combinations with US 4,830,286, US 5,636,615, US 6,126,094 and DE 100 18304 A1.
• Claims 9–11 and 16–17 (cast shaft + sintered/friction-welded silicon-steel annular plate) are the weakest obviousness link on this record and would need a joining-art reference I have not located.
• The highest-value verification step before relying on any of this: obtain the German full text and drawings of DE 100 18304 A1 (and its EP 1 146 223 A2 equivalent) to determine whether its "grooved recesses opening into a stepped expansion of the guide bore" are angularly offset from the apexes of the radial recesses 36, 38. If they are, that single reference (in view of the AAPA) largely disposes of claim 1 and much of the dependent set. I did not retrieve IT 212428 Z2 at all and make no representation about it.

Sources relied on: the patent itself, https://patents.google.com/patent/US7080819/en; https://pl.espacenet.com/publicationDetails/description?CC=US&NR=[4830286A](/patent/4830286A)&KC=A&FT=D&ND=7&date=19890516&DB=EPODOC&locale=pl_pl; https://patents.google.com/patent/[US5636615A](/patent/US5636615A)/en and https://patentimages.storage.googleapis.com/c1/96/31/01e949fa9802d6/US5636615.pdf; https://patents.google.com/patent/US5820101; https://patents.google.com/patent/[US6126094A](/patent/US6126094A)/en and https://www.freepatentsonline.com/[6126094](/patent/6126094).html; https://patents.google.com/patent/DE10018304A1/en and http://data.epo.org/gpi/EP1146223A2-Armature-plate-of-switching-magnets-in-particular-for-diesel-fuel-injectors-and-method-of-manufacturing-of-such-plate.html; https://patents.google.com/patent/JP4026592B2/en; https://patentimages.storage.googleapis.com/f2/e5/7e/8b0713f3227466/US6036460.pdf.