US 4693399

I'll search for the specific patent number and check litigation dockets.

Let me run a couple more targeted checks on litigation/CAFC dockets and the related reissue.

Search scope and limitations (read first)

I ran web searches rather than direct queries against the USPTO Patent Public Search / Patent Center APIs or the CAFC docket system — I do not have credentialed, transactional access to those databases from this environment. So the USPTO bibliographic data below comes from the authoritative patent text supplied in the prompt (fetched from patents.google.com, which mirrors USPTO data), and the litigation data comes from published court opinions surfaced by search. I found no CAFC 2026 docket activity involving this patent; the only Federal Circuit appeal I can confirm is from 1998.

Also note: the system header in my instructions gives today's date as 2026‑09‑30, while your message says April 26, 2026. I flag the discrepancy rather than silently pick one.

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Bibliographic summary — US 4,693,399

Abstract (as published): An injection-molded thermoplastic closure with shake-and-spoon apertures and associated flaps for selectively closing and opening the apertures. The flaps are releasably retained in their closed positions by catch elements which provide retention forces that are relatively insensitive to dimensional and shape variations in the body resulting from the molding process. In one embodiment, the cap has "freeze points" and a gate location that reduce the tendency of the cap to assume an oval condition when cooled from molding temperatures. A wide sealing ledge cooperates with a central support for a liner seal positioned in the cap to seal the mouth of a container.

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Independent claims in plain language

The patent has 15 claims; claims 1, 9, 12, 13, and 14 are independent (claim 15 depends on 14; claims 2–8 depend on 1; claims 10–11 depend on 9).

Claim 1 — spaced catches along the spoon flap's free edge. A one-piece injection-molded plastic cap with a circular end wall split into a "shake" side (small dispensing apertures) and a "spoon" side (a large aperture big enough to pass a spoon). Each side has its own hinged flap. The spoon flap's hinge line plus its free edge make up substantially its entire boundary. Catch elements are spaced along a line near the free edge to hold the spoon flap closed, and they run along that line for at least half the length of the free edge — so the flap is uniformly retained. (This is the "peelable retention across a long free edge" concept.)

Claim 9 — thin, un-stiffened flap with multiple catches, peelable open. Same two-mode cap. One of the flaps has a generally uniform wall thickness no greater than the cap's nominal wall thickness and is free of significant stiffening structure. Several individual catches on the flap's lower face releasably secure it. The flap is flexible enough that a user can peel it open by overcoming the catches' retention forces progressively — fewer than all catches at any one time. (The core "dimensionally forgiving / peel-open" claim.)

Claim 12 — coplanar land and sealing ledge for a liner seal. Same two-mode cap, with a chordal land area between the spoon and shake sides and each flap hinged on that land. Adds an internally threaded skirt depending from the end wall's perimeter and an annular sealing ledge on the lower/inside side of the end wall, inboard of the skirt. The land area's lower surface is generally coplanar with the sealing ledge and cooperates with it to support a sealing sheet (e.g., foil/paper liner) received in the cap. (This is the claim the Federal Circuit summarized in the 1998 appeal; see litigation note below.)

Claim 13 — wide flat sealing ledge (≥ 2× nominal wall thickness). Same two-mode cap with threaded skirt and annular sealing ledge on the lower side of the end wall inboard of the skirt, where the sealing ledge's flat surface extends radially a distance substantially equal to at least twice the cap's nominal wall thickness. (The "wide ledge tolerates ovality" claim.)

Claim 14 — thin "freeze point" zones at the ends of the land area. Same two-mode cap with a chordal land area and flaps hinged on it, where the cap thickness at the ends of the land area is substantially less than the land area's average thickness. The stated mechanism: plastic in those end zones freezes early in the molding cycle, reducing the cap's tendency to take an oval set. (This is the second-embodiment ovality-control concept; see FIGS. 7–13, elements 111 and rib 113.)

Dependent claims add: discrete spaced catches (2); catch length smaller than inter-catch spacing (3); catch arc exceeding 90° (4, with 120° given as preferred in the spec); catches engaging the spoon aperture edge (5); flap marginal area extending outwardly of the aperture (6); a thin anti-sift skirt (7) carrying the catches (8); spoon-flap version of the peelable-catch structure (10); shake-flap plug elements with catches engaging the small apertures (11); and a recessed area around the gate vestige deep enough to keep the vestige above surrounding land surfaces (15).

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Litigation history (relevant to this exact patent)

• Weatherchem Corp. v. J.L. Clark, Inc., 937 F. Supp. 1262 (N.D. Ohio 1996), aff'd in part / modified in part / vacated in part, 163 F.3d 1326 (Fed. Cir. 1998) (Nos. 98‑1064, 98‑1078). Weatherchem asserted the '399 patent (claims 12 and 13) and U.S. 4,936,494 (claims 9, 13, 14).
  • The district court held the asserted '399 claims invalid under the on-sale bar, finding the invention was on sale "at the very latest, in late September 1985," before the 1985‑10‑17 critical date (the application was filed 1986‑10‑17). The Federal Circuit applied Pfaff v. Wells Electronics and affirmed, modifying the judgment to cover only claims 12 and 13 of the '399 patent (not the whole patent). Sources: https://law.justia.com/cases/federal/appellate-courts/F3/163/1326/[494298](/patent/494298)/ ; https://openjurist.org/163/f3d/1326/weatherchem-corporation-v-jl-clark-inc ; https://storage.courtlistener.com/harvard_pdf/[760245](/patent/760245).pdf
  • The court also rejected Clark's inequitable-conduct counterclaim (no intent to deceive found), so the '399 patent was not held unenforceable as a whole.
• CAFC 2026 dockets: I found no 2026 Federal Circuit docket naming US 4,693,399. Given that the patent's anticipated expiration was 2006‑10‑17 and it is listed as "Ceased," active 2026 CAFC litigation on this patent is very unlikely — but I cannot rule it out exhaustively, because I could not query the CAFC docket database directly. My search results for "4693399 + 2026 dockets" returned only unrelated patents with superficially similar numbers (e.g., U.S. 8,549,339 in Redstone Logics v. MediaTek), which are different patents and should not be conflated with this one.

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Things I am not certain about

• Whether the reissue RE37634 E1 altered the claim numbering or scope relative to the '399 claims as issued. The '399 claims 12 and 13 were invalidated in 1998; the reissue application was filed 1996‑10‑23 (before that judgment became final on appeal). I could not retrieve the reissue's claim text in this session, so I will not speculate about what claims RE37634 ultimately contains.
• The certificate of correction dated 1995‑07‑18 — I do not know what it corrected.
• The Google Patents "Family has litigation" link points to a Darts‑IP family record (family ID 25443966); I did not open that database, so any additional litigation beyond Weatherchem v. J.L. Clark is unverified by me.

If you need authoritative confirmation of current USPTO assignment/status or a definitive CAFC docket check, that requires direct Patent Center and PACER/CAFC docket queries, which I could not perform here.

I'll search for litigation involving US patent 4693399.

Let me dig deeper for the district court case details and any other suits.

Let me verify the filing date and check for other suits, including any involving the reissue.

Litigation involving U.S. Patent No. 4,693,399

One case is known. The '399 patent (Two-flap closure; inventors John R. Hickman and Craig C. Weidman; assignee Weatherchem Corp.) was asserted in a single infringement action that was litigated through summary judgment at the district court and a Federal Circuit appeal. I found no other litigation — no ITC actions, no other district court suits, and no litigation over the related reissue patent US RE37,634 E1 — in the sources I could reach.

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Weatherchem Corporation v. J.L. Clark, Inc.

What happened:

• The district court held the asserted claims of the '399 patent invalid under the on-sale bar (35 U.S.C. § 102(b)). The critical date was October 17, 1985 (one year before the October 17, 1986 application filing). Weatherchem had sold sample caps to Durkee Foods — a February 19, 1985 purchase order for 500 caps "per your drawing Durkee # T-2 cap, Revision B dated 2-8-85," a September 3, 1985 purchase order for 275,000 caps, and thousands of sample caps shipped before the critical date. Co-inventor Hickman admitted the 2-8-85 drawing contained "the features of the patent claims."
• The district court also held the '494 patent invalid for obviousness over the '399 patent combined with the "Rosam II" cap, and alternatively not infringed.
• Notably, the court found in the alternative that the Clark caps would infringe the '399 patent if valid, that the '399 patent was not obvious, and that Weatherchem did not engage in inequitable conduct — findings the district court itself characterized as being made "for completeness and in the interest of aiding appellate review."

Federal Circuit disposition (Dec. 7, 1998) — affirmed-in-part, modified-in-part, vacated-in-part:

• Affirmed the declaratory judgment of invalidity, but modified it to encompass only claims 12 and 13 of the '399 patent (the asserted claims) and claims 9, 13, and 14 of the '494 patent — not the full patents. The court expressly noted the district court's judgment "declares both patents invalid" but that "only the asserted claims" were actually adjudicated.
• Affirmed the dismissal of Weatherchem's infringement claims and the denial of Clark's unenforceability (inequitable conduct) counterclaim.
• Vacated the declaratory judgment of noninfringement of the '494 patent and the denial of Clark's counterclaim for a declaration of noninfringement of the '399 patent (the court declined to reach infringement once invalidity was affirmed).
• Each party bore its own costs.

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Important caveats and disambiguation

1. Do not confuse this patent with other "399" patents. My searches surfaced several unrelated patents whose numbers end in 399 — e.g., U.S. 6,349,339 (Zamora Radio streaming media), U.S. 9,597,399 (Eagle Pharmaceuticals), and the Netlist '339 patent asserted against Samsung. None of those is U.S. 4,693,399. I excluded them.

2. The reissue. U.S. 4,693,399 was reissued as US RE37,634 E1 (application 08/731,975, filed October 23, 1996; reissue granted April 9, 2002). The '399 patent and its reissue appear in Google Patents with a "Family has litigation" flag pointing to a Darts-IP record for family ID 25443966. I did not find any case in which the reissue itself was asserted, and I cannot confirm what the Darts-IP flag covers beyond the Weatherchem v. J.L. Clark action described above. Treat that flag as unverified.

3. Sources I could not reach. Unified Patents' litigation portal (portal.unifiedpatents.com/litigation) and PACER did not return usable results through my search tool. My conclusion that only one case exists is based on the Federal Circuit opinions, the district court opinion (937 F. Supp. 1262), Plastics News coverage (March 3, 1997), and the Google Patents family data for US4693399A — not on a direct PACER docket query. Because the patent expired October 17, 2006 (anticipated expiration) and was marked "Ceased," post-2006 litigation is unlikely but I cannot rule it out with certainty from these sources alone.

4. Verification note on the filing date. The docket number 1:91-CV-35 is consistent with a 1991 filing in the Northern District of Ohio, and contemporaneous press reporting states 1991, but I did not retrieve the complaint itself. The exact filing month/day should be confirmed against the PACER docket if precision is required.

I'll verify the structured "no PTAB activity" default against live sources before writing.

Let me check the reissue (RE37634) and any Weatherchem enforcement history, since those would be the likeliest vehicles for a challenge.

One more check to pin down the Federal Circuit disposition and confirm no later PTAB filings.

Proceedings overview

Total AIA trial proceedings on US4693399: zero. The structured "PTAB proceedings on file" block — sourced from the USPTO Open Data Portal — returns no IPR, PGR, or CBM proceeding for this patent, and my independent web searches (Google Patents' litigation/PTAB family view, PTAB petition document mirrors, CourtListener, and general queries pairing "4,693,399" / "US4693399" with IPR/CBM) surfaced no PTAB proceeding number of any kind. The correct breakdown is therefore: active 0 / claims invalidated by the Board 0 / claims sustained by the Board 0 / settled 0 / institution denied 0 — status verbatim: "no AIA trial proceedings on file."

That said, the defensive posture for a defendant is not "no PTAB attacks, so the patent is hardened." It is the opposite, and much stronger: the '399 patent was already held invalid by a federal district court, and that invalidity judgment was affirmed by the Federal Circuit in 1998 (on-sale bar). The patent also expired on 2006-10-17, and its reissue, RE37634, shares that expiry. There is no live patent right to assert here at all — a demand letter citing claims 1–15 of US4693399 has no enforceable claim behind it.

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PTAB proceedings

None. No AIA trial was ever filed, instituted, or decided against US4693399 or its reissue USRE37634. There is consequently no panel to name, no institution decision, no Final Written Decision, no settlement, no PTAB appeal, and no § 315(e)(2) estoppel record. I am not going to invent a proceeding number to fill these fields.

This is unsurprising and is not a signal of patent strength:

• Timing. The patent issued 1987-09-15 and expired 2006-10-17. IPR/PGR/CBM practice began 2012-09-16 — roughly six years after the patent term ended. There was no AIA-trial window in which this patent was commercially worth attacking.
• Subject matter. The claims are mechanical (a two-flap condiment closure). A CBM petition would have failed the "covered business method" gate, and the durability issue that killed the patent (on-sale bar) is a non-patent/printed-publication ground outside § 311(b) — statutorily unavailable in an IPR even if someone had filed one.

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The adjudication that actually matters (not a PTAB proceeding)

Weatherchem Corp. v. J.L. Clark, Inc., No. 1:91-CV-35 (N.D. Ohio) → aff'd 163 F.3d 1326 (Fed. Cir. 1998)

• Type: District court bench trial on infringement, invalidity, and unenforceability of US4693399 and US4936494. Ordinary Article III litigation — not an AIA trial.
• Complaint filed: 1991 (docket No. 1:91-CV-35) — per the district court docket citation.
• District court decision: 1996-08-30, reported at Weatherchem Corp. v. J.L. Clark, Inc., 937 F. Supp. 1262 (N.D. Ohio 1996). Holding, as the court stated it: the court "concludes that the '399 patent is invalid due to the 'on-sale bar,' and the '494 patent is invalid because it was obvious given the prior art, which includes the enclosure embodying the claims of Weatherchem's own '399 patent."
• The '399 invalidity basis: pre-AIA § 102(b) on-sale bar. The critical date was 1985-10-17 (utility application filed 1986-10-17; the court rejected Weatherchem's attempt to claim the 1986-08-25 design-application date, holding the design application did not satisfy § 112 ¶ 1 for the claimed invention). Weatherchem sold more than a decade-and-a-half-million-dollar product line (the "Flapper") before that date: a 1985-02-19 Durkee purchase order for 500 caps "per your drawing Durkee # T-2 cap, Revision B dated 2-8-85," a 1985-08-16 firm price quote, and a 1985-09-03 purchase order for 275,000 caps at $156.04/thousand — with co-inventor Hickman admitting "the features of the patent claims can all be found in [the 1985-02-08 drawing]." The Federal Circuit: "the record supplies adequate support for the district court's conclusion that Weatherchem impermissibly placed the patented invention on sale before the critical date."
• Claim-level granularity: The district court's on-sale-bar holding was directed at the '399 patent as a whole (not a subset of claims). Note that the Federal Circuit, in the vacatur discussion, observed that a declaration of invalidity "does not extend to all claims of a patent" in connection with the '494 patent — a caution about over-reading claim-scope of the judgments. For '399, the operative disposition is invalidity of the patent, not a claim-by-claim count. I cannot state that the Board or any court canceled specific numbered claims 1–15 of '399; no such claim-by-claim cancellation exists.
• Inequitable conduct: Clark cross-appealed the district court's failure to address whether Weatherchem's non-disclosure of the premature sale constituted inequitable conduct. The Federal Circuit affirmed the district court's finding that Weatherchem had no intent to deceive, which disposed of the unenforceability issue — so the patent was invalid but not held unenforceable.
• Appeal: Weatherchem appealed (Fed. Cir. Nos. 98-1078 / 98-1064, per the reporter metadata accompanying the opinion). Disposition: AFFIRMED as to invalidity. The court vacated the declaratory judgment of non-infringement of the '494 patent and dismissed Clark's counterclaim for a declaratory judgment of non-infringement of the '399 patent, on the Lough v. Brunswick rationale that an invalidity affirmance moots infringement review.
• Post-judgment events on the face of the patent record: a certificate of correction (1995-07-18); an assignment to Weatherchem from Nickolas J. Kriska recorded 1996-10-25; a reissue application filed 1996-10-23 maturing as USRE37634E1 on 2002-04-09 (i.e., filed after the district court's invalidity judgment); and statutory disclaimers/expiry. Status on Google Patents: "Ceased."
• Defensive value: A final judgment of invalidity of '399 is binding against the patent owner under Blonder-Tongue, and its on-sale-bar defect travels with the reissue (same invention, same pre-1985-10-17 critical date, and a reissue cannot obtain term beyond the original patent). Combined with expiry on 2006-10-17, this patent has no assertable claim. Any demand letter invoking US4693399 or RE37634 is asserting a dead — and judicially invalidated — right.

Sources: district court opinion — https://www.courtlistener.com/opinion/[2250493](/patent/2250493)/weatherchem-corp-v-jl-clark-inc/ ; Federal Circuit opinion — https://www.courtlistener.com/opinion/[760245](/patent/760245)/weatherchem-corporation-v-jl-clark-inc-defendantcross-appellant/ (also https://law.justia.com/cases/federal/appellate-courts/F3/163/1326/[494298](/patent/494298)/ and https://law.resource.org/pub/us/case/reporter/F3/163/163.F3d.1326.98-1078.98-1064.html ).

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Strategic summary

Claim status. There is no PTAB-driven narrowing to map, because there were no PTAB proceedings. On the Article III record, all 15 claims of US4693399 are subject to a district court judgment of invalidity under the on-sale bar, affirmed on appeal — the court held the "'399 patent is invalid," not a subset of claims. Nothing in the '399 patent is "sustained" or merely "untested" by a tribunal; the patent as an enforcement instrument was extinguished in 1996–1998 and its term ended 2006-10-17. The reissue USRE37634 (granted 2002-04-09) technically gets its own claim set, and those reissue claims were never adjudicated — but they expired with the original patent term on 2006-10-17, so the "untested reissue claims" gap is a theoretical point, not a live exposure. Separately, the sibling patent US4936494 (claims 9, 13, 14 asserted) was held obvious over the '399 disclosure plus the Rosam II cap.

Estoppel landscape. There is no § 315(e)(2) estoppel against anyone — no IPR means no petitioner and no privies are estopped, on any ground. The flip side is that a defendant doesn't need IPR-art freedom: the invalidity judgment itself plus expiration disposes of the matter. Note the important asymmetry that worked against Weatherchem and in favor of defendants: the ground that killed the patent (on-sale bar) is statutorily unavailable in an IPR under 35 U.S.C. § 311(b), which limits IPR to patents and printed publications. So even in a hypothetical IPR, § 103 art (the 9 references cited on the face of the patent, plus the Rosam II cap and Durkee/Durkee-competitor activity) would have been a separate fight from the on-sale bar.

Pattern signals. No serial petitioner activity, no defensive aggregator (no Unified Patents / RPX filing anywhere in the record), no PTAB appeals. The only IPR-adjacent signal is Google Patents' "Family has litigation" flag pointing to a Darts-ip litigation dataset — that is the 1991–1998 Weatherchem v. J.L. Clark case described above, plus later enforcement episodes referenced in the Appendix of Gateway Plastics, Inc. v. Weatherchem Corp. (E.D. Wis., Case Nos. 02-C-0670 / 02-C-0870, 2002–2004). Weatherchem (Twinsburg, Ohio) was the aggressive enforcer here, not a responding patent owner — and its enforcement program against this patent ended in invalidity.

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Recommended next steps

1. If you are a defendant and a demand letter cites US4693399: respond with the invalidity judgment, not with a PTAB argument. Quote the district court's own words: the court "concludes that the '399 patent is invalid due to the 'on-sale bar'" (Weatherchem Corp. v. J.L. Clark, Inc., 937 F. Supp. 1262, 1264 (N.D. Ohio 1996), https://www.courtlistener.com/opinion/2250493/weatherchem-corp-v-jl-clark-inc/), affirmed at Weatherchem Corp. v. J.L. Clark, Inc., 163 F.3d 1326 (Fed. Cir. 1998), https://www.courtlistener.com/opinion/760245/weatherchem-corporation-v-jl-clark-inc-defendantcross-appellant/. Add Blonder-Tongue Labs. v. Univ. of Illinois Found., 402 U.S. 313 (1971) for the preclusive effect.
2. Check which patent number the demand actually cites. If it cites RE37634 rather than the original, the response is simpler still: the reissue's term runs only for the unexpired portion of the original patent's term, which ended 2006-10-17. Ask for the asserted claim, the accused product, and the date of first infringement — there is no period in which a live, valid claim existed, so there is no damages window.
3. If you are evaluating the patent for a clearance/FTO opinion: treat US4693399 and USRE37634 as expired and judicially invalidated. Design freedom around this disclosure is unconstrained; the more relevant modern closures in this family art are the later Weatherchem/Gateway/Sonoco/AptarGroup patents that cite '399 (137+ forward citations listed on Google Patents), not '399 itself.
4. Monitoring. No trial-stage milestones exist to track — no institution-decision deadline, no oral hearing, no statutory 1-year FWD deadline, because no trial was instituted. If you want independent confirmation, query PTAB E2E / the PTAB public search (https://ptacts.uspto.gov/ptabweb) by patent number before relying on the ODP ingest: as of 2026-09-30 I found no proceeding, and I am flagging this as the verified default rather than as a positive finding of activity.

Caveat on confidence: the zero-count PTAB result rests on (a) the structured ODP block in this prompt and (b) search coverage of Google Patents, PTAB petition document mirrors, and CourtListener. I could not query PTAB E2E directly from this session. If the stakes justify it, a docket-level E2E search by "4693399" and by "RE37634" is the one remaining confirmation step — but I have no affirmative evidence of any proceeding, and every indicator points the other way.

I'll search for the assignment record data on this patent before writing anything.

Let me try targeted searches for the recorded assignment reel/frame data.

I found reel/frame data embedded in the authoritative patent text. Let me verify the parties and check for later transfers.

I hit the tool-call limit while verifying, so here is the reconstruction based on the authoritative patent text plus what the searches returned. Important sourcing caveat up front: I could not query USPTO Assignment Center directly (no credentialed access, and my searches for the reel/frame index returned no usable results). The two reels/frames below come from the assignment records embedded in the authoritative patent text's legal-events feed (patents.google.com/patent/US4693399A), which mirrors the USPTO assignment data. That feed is not guaranteed complete — Google Patents' legal-events list frequently omits security interests, later corporate transfers, and merger/change-of-name records. Treat the absence of further records as unverified, not as proof of none.

Inventors

Pattern notes.

• No inventor-departure signal. Hickman was still at Weatherchem in 1996 (trial testimony). Weidman was still filing Weatherchem applications in ~1988 for the '494. There is no evidence of inventors bailing out within 12 months of filing — the opposite of the pre-fire-sale pattern. I have no resignation/employment-end dates for either inventor, so I cannot fully rule out later departures.
• A third name appears in the record years later — Nickolas J. Kriska. Kriska is listed as co-inventor with Hickman on the parent application 06/899,935 (filed 1986-08-25), which issued as design patent D305206 ("Two flap container cap," granted 1989-12-26, assignee Weatherchem Corporation). He is therefore in the priority family but is not a named inventor on the '399 patent itself. His 1996 assignment of interest (below) is a title-cleanup artifact, not an inventor transfer.
• Inventor addresses (Ohio, and Maryland for Kriska) are consistent with a small regional molding manufacturer, not a broker.

Original assignee

Weatherchem Corporation, a corporation of Ohio — 8500 Sweet Valley Dr., Twinsburg, Ohio (the Twinsburg, OH address is the one used consistently across the family: D305206, D331878, D603702, D603703, and later '699-era patents).

• Primary line of business: custom injection molding, specifically one-piece hinged dispensing closures for spice, condiment, and food-service containers. The '399 specification itself recites polypropylene molding and a 0.050-inch nominal wall — this is a manufacturing company's patent.
• Did they ship a product embodying the claims? Yes, unambiguously, and before the filing date. This is the very fact that killed the patent. The Federal Circuit found a 1985-02-19 Durkee Foods purchase order for 500 caps "per your drawing Durkee # T-2 cap, Revision B dated 2-8-85"; a 1985-07-17 order for 990 more sample caps; a 1985-09-03 purchase order for 275,000 caps at the quoted firm price; and regular mass production for Durkee beginning 1986-01-03, with full production at about 440,000 caps per week (Fed. Cir. ¶14). The commercial product line was known as the "Flapper." The asserted claims 12 and 13 were held invalid under the pre-AIA on-sale bar, Weatherchem Corp. v. J.L. Clark, Inc., 937 F. Supp. 1262 (N.D. Ohio 1996), aff'd 163 F.3d 1326 (Fed. Cir. 1998).
• Current status: Appears still operating; no evidence of bankruptcy, dissolution, or acquisition. Google Patents lists "Weatherchem Corp" as current assignee of '399. More tellingly, Weatherchem Corporation continued obtaining U.S. patents on this same product family for decades after — through the "Sift-resistant dispensing closure" family (e.g., U.S. 8,550,313 B2 in 2013 and U.S. 11,548,699 B2 granted 2023-01-10). A company filing and taking grants in 2023 is not a dissolved shell.
  • Caveat: I did not verify a current Ohio Secretary of State registration, and I did not confirm any change of control. My search for Weatherchem's acquisition history was cut off by the tool-call limit. If a definitive "is Weatherchem still independent" answer matters, that requires a state corporate registry / Dun & Bradstreet check I could not complete.

Assignment timeline

Two recorded assignments appear in the authoritative record. Both are inventor-to-employer conveyances. There is no post-issuance third-party transfer of any kind in the data I can reach.

• 1986-10-13 (executed) / recorded 1986-11-06 — Reel 004626/0927

  • Conveyance: Assignment of assignors' interest ("ASSIGNMENT OF ASSIGNORS INTEREST")
  • Assignor: HICKMAN, JOHN R.; WEIDMAN, CRAIG C.
  • Assignee: WEATHERCHEM CORPORATION, a corporation of Ohio
  • Correspondent: Not retrieved. The legal-events feed carries the reel/frame and the assignment text but not the recording correspondent, and I could not open Assignment Center to pull it. I will not guess. (Related but distinct: the prosecuting law firm of record on the sibling parent application D305206 / app 06/899,935 is Pearne, Gordon, McCoy & Granger — that is prosecution counsel, not a confirmed assignment correspondent, and should not be conflated.)
  • Context: Standard employment/inventor assignment — executed four days before the 1986-10-17 filing date, i.e., title was perfected pre-filing. Ordinary operating-company housekeeping. Note the effective date (1986-10-13) is earlier than the 1986-10-17 filing date and earlier than the 1986-11-06 recording date.

• 1996-10-15 (executed) / recorded 1996-10-25 — Reel 008186/0520

  • Conveyance: Assignment of assignor's interest ("ASSIGNMENT OF ASSIGNORS INTEREST; ASSIGNOR: KRISKA, NICKOLAS J.")
  • Assignor: KRISKA, NICKOLAS J.
  • Assignee: WEATHERCHEM CORPORATION, Ohio
  • Correspondent: Not retrieved — same limitation as above.
  • Context: Title clean-up / quieting a residual family interest, not an acquisition. (Inference, flagged as such: Kriska is the co-inventor of the 1986-08-25 parent application 06/899,935 / D305206 but not of '399; his rights in the family had to be papered to Weatherchem. The timing is the tell — the document executed 1996-10-15, eight days before Weatherchem filed reissue application 08/731,975 on 1996-10-23. A patent owner does not normally paper a stray inventor's interest and file a reissue in the same eight-day window unless the two are connected. I have not seen the reissue's transmittal documents, so I cannot confirm that link.)

On the reissue

The reissue US RE37,634 E1 (app 08/731,975, filed 1996-10-23, granted 2002-04-09) issued to Weatherchem. Notably, it was filed roughly eight weeks after the district court invalidated the patent on 1996-08-30 — 163 F.3d 1326 confirms the judgment and the 937 F. Supp. 1262 decision. I could not retrieve the reissue's own assignment/annex record, so I cannot state whether additional reel/frame entries attach to RE37,634 rather than to '399. Anyone reconstructing this chain must search Assignment Center for both 4693399 AND RE37634 — reissues usually get their own assignment entries.

What is conspicuously absent

No security agreement, no merger, no change of name, no release, no correction — and no third-party assignee at any point. Given that Weatherchem litigated this patent hard (J.L. Clark, and later Gateway Plastics in E.D. Wis. Nos. 02-C-0670 / 02-C-0870), the absence of any monetization transfer is consistent with a manufacturer that kept and enforced its own patents. But I flag this as a limitation of the Google Patents feed, not a verified null result. If Weatherchem was ever rolled up or pledged its IP to a lender, that record would not necessarily surface in this feed. Direct Assignment Center / Patent Center lookup is the only way to close that gap.

Timeline diagram

timeline
    title Ownership of US 4693399
    1986 : Filed 17 Oct by Weatherchem
         : Hickman and Weidman assign to employer
    1987 : Patent issued 15 Sep
    1991 : Weatherchem sues JL Clark
    1996 : Kriska assigns remaining interest
         : District court invalidates the patent
    1998 : Invalidity affirmed on appeal
    2002 : Reissue RE37634 granted
    2006 : Patent term expires

NPE / troll-pattern signals

Verdict

Operating-company assertion.

Cite: Reel 004626/0927 (executed 1986-10-13, recorded 1986-11-06) and Reel 008186/0520 (executed 1996-10-15, recorded 1996-10-25) both run to Weatherchem Corporation, an Ohio corporation, and the patent issued to and remained with that same operating manufacturer — there is no licensing entity, no LLC, and no transfer to any known asserter at any point in the record. Weatherchem shipped the claimed product (the Durkee "Flapper" cap: 275,000 units ordered 1985-09-03, full production ~440,000 caps/week by January 1986) and asserted the patent in its own name against a direct competitor, J.L. Clark, Inc., 163 F.3d 1326 (Fed. Cir. 1998) — the textbook operating-company profile, and the reason the case is famous is the on-sale bar the sales activity triggered, not any monetization strategy. The one thing a reader must not carry away is an "NPE risk" impression: there is no NPE here, and there is also no live asset here — claims 12 and 13 were held invalid, the judgment was affirmed on appeal and is binding under Blonder-Tongue, and the term expired 2006-10-17.

Verify at: USPTO Assignment Center — https://assignmentcenter.uspto.gov/ (legacy interface: https://assignment.uspto.gov/patent/index.html) — searching both patent number 4693399 and reissue RE37634, and pulling the correspondent-of-record field on Reels 004626/0927 and 008186/0520 to close signal #3.

Residual uncertainty (stated plainly): (a) I never reached Assignment Center, so any 1996–2006 assignment record absent from the Google Patents feed would have escaped me — most plausibly a security interest or a change-of-name, not a transfer to an NPE; (b) I could not retrieve the recording correspondent for either reel; (c) I did not verify Weatherchem's current corporate registration or whether it was ever acquired. Items (a) and (c) are the two that could, in principle, alter the verdict — though nothing in the product, litigation, or patent-prosecution record points that way.

I'll research each cited reference to map its disclosure against the '399 claims. Let me pull the primary sources.

Now the remaining cited references.

Prior-Art Analysis — US4693399 ("Two-flap closure")

Scope, method, and a flagged callout

What I searched. I could not run a credentialed query against the USPTO Patent Public Search or Patent Center APIs from this session. The bibliographic and citation data below comes from the authoritative patent text supplied in the prompt (patents.google.com's mirror of USPTO data) for US4693399A, supplemented by targeted web searches to retrieve the content of individual cited references. Where a reference's content is verified against a primary source (its own text/PDF), I say so. Where I could not retrieve it, I say so and mark the assessment low-confidence rather than fabricating a disclosure.

Which references are "the citations for 4693399." US4693399A carries nine US patent documents in its "References Cited" (Patent Citations) section. Those nine are the examiner-facing citation set and are the objects of this analysis:

A separate table on US4693399A — "Family Cites Families (6)" — lists documents cited in the foreign family (CA1245601, DE3734156, FR2605294, GB2197857) rather than by the '399 examiner: US3018931A (French Co. R.T., closure for condiment containers, 1959-05-15/1962-01-30); US3255907A (Wheeling Stamping, linerless screw closure, 1964-01-13/1966-06-14); US3140019A (Nibot Corp., dispenser top, 1962-02-26/1964-07-07); GB1178362A (Leslie Beddoe, closure plugs for containers, 1968-01-16/1970-01-21); NZ183806A (Dart Industries, spice shaker set, 1976-06-04/1980-10-24); and US4714181A (Durkee Industrial Foods, condiment bottle cap, filed 1986-08-21 / published 1987-12-22). I treat these separately because they are not part of the '399 examination record, and US4714181A in particular post-dates the '399 filing and therefore is not §102 prior art to it.

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Statutory posture of the citation set (this frames every §102 mapping below)

Under pre-AIA law governing this 1986 application, the §102(b) critical date is 1985-10-17 (one year before the 1986-10-17 filing). Eight of the nine references published before that date and are therefore facially §102(b) art. Each is also §102(e) art as of its own US filing date:

• §102(b) art (published before 1985-10-17): US3493150A, US4163496A, US4361250A, US4369901A, US4463869A, US4494679A, USD278602, US4545508A.
• Not §102(b), but §102(e) as of 1984-12-31: US4580687A — published 1986-04-08, i.e. inside the one-year grace period. It is only available as §102(e) art on its filing date (1984-12-31), which does precede both the 1985-10-17 critical date and the 1986-08-25 parent filing.
• Design patent caveat: USD278602 has no utility claims; its claim is to ornamentation. It can serve as prior art only to the extent its drawing discloses structure, and it cannot "anticipate" apparatus claims 1/9/12/13/14 in the ordinary element-for-element sense.

The transactionally decisive point. None of these nine references is what invalidated the patent. The judgment that killed the asserted claims rested on the on-sale bar, pre-AIA §102(b) — Durkee purchase orders and the 1985-02-08 drawing T-2 Rev. B (see the litigation sections already generated). A §102(b) on-sale-bar activity is not a "reference," so it maps to no citation on the face of the patent. The cited references remain relevant as §103 art and as the backdrop against which claim 1/9's distinguishing features must be read.

Flagged contradiction between the two earlier sections. The "Litigation history" section states the Federal Circuit modified the judgment to cover only claims 12 and 13 of the '399 patent, while the "PTAB challenges" section states the district court held the "'399 patent is invalid" as a whole and that "I cannot state that … specific numbered claims 1–15 … canceled." Those two statements are in tension on the claim-level scope of the invalidity judgment. The safer statement, and the one supported by the Federal Circuit's own Lough v. Brunswick mootness discussion, is: the only '399 claims actually adjudicated were 12 and 13; claims 1–11, 14, and 15 were never the subject of a validity holding.

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Reference-by-reference §102 analysis

1. US4545508A — Kraft, Inc., "Plastic closure for grated cheese or the like"

Filed 1983-01-10; published 1985-10-08 (verified against the patent PDF and USPTO/report text).
Disclosure (verified): A one-piece injection-molded closure with a two-mode top: a large central "bulk access" aperture with a hinged lid 40, and smaller circular "broadcast" openings 20, 22 with a separate hinged annular lid 24. Each lid is retained by tongue-in-groove fitment — projections 50 project orthogonally from the depending collar 46 of lid 40 and frictionally co-act with the side wall 51 of the bulk-access aperture; lid 24 uses beveled posts 30, 32 compressed into openings 20, 22, giving a "snap-fit engagement … which provides the consumer with a tactile signal." Critically for the '399, the patent teaches that lid 40 can be released by distortion of the lid itself: upward pressure "will … distort the lid 40 by elongating it along the axis of hinge movement, while compressing its diameter in a transverse direction, such that the tongue-in-groove fitment is readily released." The patent also addresses molding-induced distortion, stating that reinforcing braces terminate at ridge 77 "so as not to interfere with the maintenance of a smooth circular shape of the opening, upon cooling of the organopolymeric material," thereby maintaining a fit "without preferential shrinking."
§102 posture: §102(b); §102(e) as of 1983-01-10.
Claims potentially affected: Claim 9 is the real exposure — the reference expressly discloses a two-mode closure with a thin, un-ribbed in-use hinged flap that a user releases by flexing/distorting the flap, i.e. the "flexible, dimensionally forgiving flap" concept, though it discloses that release as a diametric distortion rather than as progressive release of a plurality of individual catches (which claim 9 requires as "fewer than all of the catches … at any given time"). Claims 6–8 (marginal area; thin anti-sift skirt/collar 46 projecting into the aperture) are also squarely taught. The cooling/shrinking discussion bears on claim 14's problem statement, though Kraft's solution (limiting rib intrusion) is structurally different from the '399's thin end-zone "freeze points."
Confidence: High on disclosure; the claim-9 mapping is a strong §103 combination argument, not a clean anticipation.

2. US4463869A — Continental Plastics, Inc. (Duane H. Lewis), "Tamper-evident spice can lid"

Filed 1983-08-04; published 1984-08-07 (verified against the patent PDF and text).
Disclosure (verified): A two-cover spice-can lid — a spooning cover 29 over aperture 19 in recess 17, and a sifting cover 71 over aperture 61 in a second recess 59. Each cover is integrally hinged at its rear and locked by a depending locking lip (43 / 79) that engages a wall (45 / 81) of the dispensing aperture. The front portion of cover 71 "will flex along groove 83, while the main portion of the cover remains in closed position, by engagement of locking lip 79 with a wall 81 of aperture 61, until the front portion is sufficiently raised to provide a grip."
§102 posture: §102(b); §102(e) as of 1983-08-04.
Claims potentially affected: This is the closest reference on the partial/sequential release idea and thus bears directly on claim 9. It discloses a flap that remains latched at one region while another region flexes free — functionally the "peeling" behavior. It does not, however, disclose a plurality of discrete catches on the lower face (it has a single locking lip), so claim 9's "a plurality of individual catch means" is not met on the face of the reference. It also teaches a locking lip engaging the edge of a dispensing aperture (claim 5 analog) and a cover seated flush in a recess. Relevant to claims 1, 5, 9 as §103 art.
Confidence: High on disclosure (primary source retrieved).

3. US4494679A — The C. F. Sauer Company (Bruce T. Cleevely), "Thermoplastic container closure for dispensing solids"

Filed 1982-07-26 (App. 06/402,159); published 1985-01-22 (verified against the patent PDF and USPTO/report text).
Disclosure (verified): A thermoplastic closure with an annular base 3 and threaded depending cylindrical wall; a raised platform 13 forming a first planar surface 15 with dispensing apertures "a" ("sifter openings"); an integral step/riser 25 dividing the raised area into a lower elevated area 15 and a higher elevated area/shoulder 19; and a closure flap 27 hinged at 29 (thinned flexible membrane) to the shoulder. The flap's lower surface carries projection(s) 35 that mate with the apertures, the aperture edges being beveled so the projection "frictionally engage[s] the walls about the apertures … to frictionally but releasably retain the flap 27 in closed position." The patent expressly keeps the apertures and projections remote from the hinge so the projections "more closely approach parallelism with the axes of the several holes." The rim of the container neck "forms a seal against and support for the undersurface of the base 3 within the circumference of the base 3." The closure "possesses flexibility that thermo[-forming]…"
§102 posture: §102(b); §102(e) as of 1982-07-26.
Claims potentially affected: Claim 11 (plug elements on the flap arranged to fit into the small apertures, with catch means engaging the apertures) is the most directly implicated — US4494679 teaches exactly projection-in-aperture frictional retention. Claim 9's "plurality of individual catch means spaced on a lower face" is partially taught (multiple projections), but the reference is a single-flap, single-mode closure, so it cannot meet claim 9's two-mode preamble. The "seal against and support for the undersurface of the base" language is relevant to claims 12/13 but discloses no coplanar chordal land and no radially-measured wide flat ledge.
Confidence: High on disclosure.

4. US4369901A — Walter E. Hidding, "Snap-up cover for spice dispenser"

Filed 1981-03-05 (App. 06/240,893); published 1983-01-25 (verified against the patent text).
Disclosure (verified): A unitary closure with a spooning cap 40 over a "pendantly skirted, sector-shaped spooning opening 34" and a sifter cap 42 over "a plurality of sifter holes 36 … with tapered, conical sidewalls," the caps hingedly interconnected by a strap 44 over a valley 32 between two raised platforms. The spooning cap has a pendant internal skirt 48 which sealably fits in the spooning opening 34; the sifter cap has tubular posts 50 which sealably penetrate the tapered holes 36 in the closed condition. The caps carry lifter bars 52 for fingernail access and snap-fit protuberances/niches (54/56, 58/60) providing an overcentering lock.
§102 posture: §102(b); §102(e) as of 1981-03-05.
Claims potentially affected: Directly relevant to claims 7 and 8 (a thin skirt cooperating with the spoon aperture to avoid sifting, with catches disposed on that skirt) and to claim 11 (plug-like posts received in the small apertures). Structurally it also anticipates the preamble environment of claims 1 and 9 (two-mode, two-cap spice closure). It does not disclose catches spaced along the spoon flap's free edge for ≥ half its length (claim 1) or a peel-release plurality of catches (claim 9). Note that Hidding's own background identifies US 3,217,949 (Davis) as the two-flap spice-closure prior art — see below.
Confidence: High on disclosure.

5. US4361250A — J. L. Clark Manufacturing Co. (inventor Foster), "Plastic container closure"

Filed 1981-06-26; published 1982-11-30. I did not retrieve the full text of this reference directly. The most reliable description I have is from US4463869A's own "Background" (primary source retrieved), which summarizes it: "In U.S. Pat. No. 4,361,250 a plastic container lid is disclosed having an integral cover for a dispensing opening in the lid in which side pieces on the cover, which are connected to the cover by frangible webs, are formed with pins which enter holes in the lid as the cover is initially closed. The ends of the pins are then heat staked … The cover has lugs which snap into the dispensing aperture in the lid to provide for reclosing after it has first been opened. This construction requires a plurality of manufacturing steps … including molding and heat staking." Corroborating citation from US6299033B1's reference list: "4,361,250 11/1982 Foster." Also referenced in US2008/0093394A1 as "U.S. Pat. No. 4,361,250 to Foster … assigned to the present assignee [J. L. Clark]."
§102 posture: §102(b); §102(e) as of 1981-06-26.
Claims potentially affected: Claim 1/5 — a cover with lugs that snap into the dispensing aperture to releasably retain it, i.e. catch means engaging the edge of the aperture. Weaker on the "spaced along a line … ≥ half the free edge" limitation. Also relevant to claim 9 as a snap-fitting, releasably retained cover, though the "peel a plurality of catches" behavior is not reported.
Confidence: Medium — description is second-hand (via the '869 background and later patents), not the reference's own text. Treat the specific element mapping as provisional. Notably, this is a J. L. Clark reference — the same company that later defeated the '399 in litigation.

6. US4580687A — Duane H. Lewis, "Low profile dispensing cap"

Filed 1984-12-31; published 1986-04-08. Not retrieved; assessment is low-confidence.
§102 posture: The only citation that is not §102(b) art. It published 1986-04-08 — after the 1985-10-17 critical date — so it is available only as §102(e) art on its 1984-12-31 filing date (or as §102(a)/§102(e) art against a later-proven invention date).
Claims potentially affected: Given the title and its authorship (the same Duane H. Lewis who invented US4463869A for Continental Plastics), the expectation is a hinged/flip dispensing cap with snap or plug retention. I will not assign specific claim mapping without the text. Verify before relying on it. Note the timing asymmetry: because it is only §102(e) art, if the '399's invention date could be carried back before 1984-12-31 (e.g. via the 1986-08-25 parent, which the district court held failed under §112 ¶1), this reference would drop out entirely.
Confidence: Low. Flagged rather than estimated.

7. US3493150A — Procter & Gamble, "Package closure"

Filed/priority 1967-12-21; published 1970-02-03. Not retrieved in this session.
§102 posture: §102(b); §102(e) as of 1967-12-21. It is the oldest reference in the set.
Claims potentially affected: On the face of the record I can only say it is a closure-arts reference of the late 1960s. I decline to assert what it discloses. Given its age relative to the hinged-flap art (the '399's own background traces the two-flap spice closure to Davis US 3,217,949, 1965), it is unlikely to be the closest art on claims 1/9/12/13/14.
Confidence: Low / unverified.

8. US4163496A — P. Ferrero & C. S.p.A., "Container for dispensing small objects"

Filed 1976-10-04; published 1979-08-07. Not retrieved in this session.
§102 posture: §102(b); §102(e) as of 1976-10-04.
Claims potentially affected: The title indicates a dispensing container for small objects (confectionery/confetti-type products) — i.e. a shake/dispense arts reference rather than a spoon-and-shake closure. Most plausibly relevant to the shake side of claim 1 / claim 11. I decline to assert specific element mapping.
Confidence: Low / unverified.

9. USD278602 — Florence Rosenstein, "Plastic threaded cover for a container" (design)

Filed 1982-11-19; published 1985-04-30. Not retrieved in this session.
§102 posture: §102(b) as to publication; but as a design patent it claims only ornamental appearance. For §102 purposes its disclosure is limited to what its drawing shows. It cannot anticipate the apparatus claims element-for-element in the ordinary way.
Claims potentially affected: At most, ornamental/flat-top or threaded-skirt environment for claims 12/13's threaded skirt limitation.
Confidence: Low / unverified.

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Prior art the '399 specification itself identifies (not in the citation list)

These matter more than several of the nine, and they should be in any §102/§103 file:

• US 3,217,949 (Davis) — a domestic spice container with "a plastic closure comprising a flap for sealing a spoon opening and a separate flap for sealing a sifter opening, … mounted atop a container body by means of an integral hinge section situated between the flaps." This is the two-flap closure concept itself, and it is surfaced in the '399 record only indirectly — as the background of Hidding's US4369901A. It is the single most on-point structural reference for claim 1's preamble and claim 9's preamble.
• The "Rosam II" cap — the secondary reference the district court used, with the '399 disclosure, to invalidate US4936494 (the sibling Weatherchem patent, not this one) for obviousness. It is part of this patent family's invalidity narrative even though it is not a citation of '399.
• The applicant's own CIP parent, US 899,935 (filed 1986-08-25) — listed under "Related Parent Applications." The district court rejected Weatherchem's attempt to carry the '399's date back to it, holding it did not satisfy §112 ¶1 for the claimed invention; that failure is what made 1985-10-17 the operative critical date and what made the Durkee pre-critical-date sales fatal. (Minor inconsistency to note: the earlier litigation summary describes US 899,935 as a "design application," whereas the Google Patents record styles it a "Continuation-In-Part." I cannot resolve which is correct from the sources I reached.)
• US4714181A (Durkee Industrial Foods, "Condiment bottle cap," filed 1986-08-21, published 1987-12-22) — appears in the "Family Cites Families" table. It is not §102 art against the '399 (it post-dates the '399 filing), but it is worth flagging because Durkee is the very customer whose 1985 purchase orders created the on-sale bar, and Durkee filed its own condiment-cap application the month before the '399's parent.

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Claim-by-claim prior-art matrix (§102 screening)

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Bottom line

1. The most relevant cited prior art, ranked: (1) US4545508A (Kraft) — two-mode hinged-lid closure with tongue-in-groove retention and an express teaching of distorting the lid to release the fitment, plus a cooling/shrinkage discussion; (2) US4463869A (Continental Plastics / Lewis) — two-cover spice-can lid with a cover that flexes free at one region while remaining locked at another; (3) US4494679A (Sauer / Cleevely) — hinged flap with projections frictionally retained in dispensing apertures and a container-rim/base sealing relationship; (4) US4369901A (Hidding) — two-cap spice dispenser with sealing skirt and posts in the sifter holes; (5) US4361250A (J. L. Clark / Foster) — cover with lugs snapping into the dispensing aperture. The remaining four (US4580687A, US3493150A, US4163496A, USD278602) are peripheral, and three of them I could not verify.

2. No single one of the nine anticipates any independent claim of US4693399. The claims' distinguishing subject matter — discrete catches distributed along ≥ half the spoon flap's free edge (claim 1), a plurality of individual catches on a thin un-stiffened flap peelable one-or-two at a time (claim 9), the coplanar chordal land / sealing ledge liner support (claim 12), the ≥ 2× radial flat ledge (claim 13), and the thin freeze-point land ends (claim 14) — is nowhere disclosed in this citation set. This is consistent with the fact that the examiner allowed the claims over them, and with the district court's express alternative finding that the '399 patent was not obvious.

3. The §102 theory that actually defeated the patent is an on-sale bar, not a reference. Pre-AIA §102(b); critical date 1985-10-17; predicate = Durkee's 1985-02-19 order for 500 caps per drawing T-2 Rev. B dated 2-8-85, the 1985-08-16 quote, and the 1985-09-03 order for 275,000 caps. That ground is statutorily unavailable in an IPR under §311(b) — which is why no AIA trial was ever a viable vehicle here (see the PTAB section).

4. Two verification items I am explicitly not asserting. (a) I did not retrieve the full text of US3493150A, US4163496A, USD278602, or US4580687A, and my description of US4361250A is second-hand via US4463869A's background. If a formal §102 chart is required, those five need to be pulled from the USPTO full-text database directly. (b) The claim-level scope of the 1998 invalidity judgment is stated inconsistently in the two earlier sections; on the authority of the Federal Circuit's own disposition, the adjudicated '399 claims were 12 and 13 only.

Suggested next step: pull the full texts of US3493150A, US4163496A, US4361250A, US4580687A, and USD278602 from USPTO Patent Public Search (or Patent Center for the PDFs), and run the same element-by-element §102 chart against independent claims 1, 9, 12, 13, and 14 — with US 3,217,949 (Davis) added as the closest-art reference the patent's own record omits.

I'll build on the prior-art section, but first verify the references that section flagged as unretrieved — §103 motivation-to-combine analysis is only as good as the disclosure facts underneath it.

Obviousness Analysis — US 4,693,399 Under 35 U.S.C. § 103

Scope note. This section builds directly on the prior-art analysis already generated. I ran additional targeted searches to retrieve the five references that section flagged as unverified, and I report the corrections below. I did not re-run the litigation, PTAB, or assignment work.

Date discrepancy (carried forward, unresolved): my operating header gives today as 2026‑09‑30; the task instruction says April 26, 2026. I am not silently choosing one. Nothing in this §103 analysis turns on the difference, since the patent expired 2006‑10‑17.

Governing law: pre‑AIA § 103(a) (the application was filed 1986‑10‑17; no AIA transition provision applies). § 103 is analyzed under Graham v. John Deere Co., 383 U.S. 1 (1966), and KSR Int'l Co. v. Teleflex Inc., 550 U.S. 398 (2007).

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Part 0 — Corrections to the prior-art section

That section correctly declined to assert disclosures it could not retrieve. I can now retire four of those five gaps, and two of its assessments change materially.

Two contradictions I am flagging, not resolving silently:

1. Claim-9 exposure changes. The prior section's bottom line said "No single one of the nine anticipates any independent claim" — that conclusion still holds. But it also implied the nine were thin on claim 9. With US3493150A and US4580687A verified, the citation set now contains two independent teachings of a plug carrying a camming lead-in plus a retaining shoulder/undercut (US3493150A's frustoconical lower portion + enlarged central cylindrical portion; US4580687A's conical base 52 + tang 56). Claim 9's §103 case is meaningfully stronger than that section suggested.

2. Identifier not auto-corrected. The References Cited list printed on US4580687A reads literally: "4,561,250 1/1982 Foster ...... 220/254 X." Per the strict instruction, I do not auto-correct this to US 4,361,250. I note only that a Foster reference in class 220/254 in that period corresponds to the "Plastic container closure" cited on the '399 as US4361250A; the printed number is what it is, and it should be checked against the granted copy before being relied on in an invalidity contention.

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Part 1 — Level of ordinary skill in the art (PHOSITA)

The '399's field is injection-molded thermoplastic dispensing closures for spice, condiment, and food-service containers — class B65D 47/08. A POSITA at the 1985 critical date is:

• a mechanical/packaging engineer with roughly a B.S. in mechanical or plastics engineering plus 2–4 years designing molded closures, or the equivalent in a closure-manufacturing engineering department (Weatherchem's own profile);
• familiar with living-hinge polypropylene design, snap-fit mechanics (camming lead-ins, undercuts, interference fits, retention vs. release force), and parting-line and gate placement;
• familiar with multi-cavity injection-molding shrinkage and warpage behavior in asymmetric parts, and with the standard levers for controlling it (wall-thickness variation, ribbing, gate location, cooling).

Evidence for this level: the references themselves are written at exactly this register — US4580687A states "With a cap thickness of about 0.060 inch…"; US3493150A gives a designed wall taper ".035 inch at its center section and .090 inch at the periphery" and a hinge ".010 to .015 inch"; the '399 gives a 0.050 in nominal wall, 0.079 in lip depth, 0.035 in lip thickness. These are the working numbers of a closure design engineer, not a layperson.

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Part 2 — The motivation-to-combine record (this is unusually strong here)

Under KSR, a combination is properly motivated by the "interrelated teachings of multiple patents," the "design incentives and other market forces," "any need or problem known in the field," and the "background knowledge, creativity, and common sense" of the POSITA. The '399 citation set is a dense, self-referential art cluster — the references cite each other and expressly criticize each other — which supplies the articulation directly rather than requiring resort to common sense.

(A) Express criticism of a reference by another reference — the Davis → Hidding line.
US4369901 (Hidding) devotes its Background to US 3,217,949 (Davis) and states that "the device of the Davis Patent is subject to serious drawbacks," specifically that "in use, both closure flaps can be raised at the same time with a consequent potential for dispensing excessive and wasteful amounts," and that "the springiness of the plastic material … biases the flaps away from the fully open condition." Hidding's stated solution is an overcentering lock. This is a textbook articulated motivation to modify a two-flap spoon/sifter closure's flap-retention scheme.
Sources: https://patents.justia.com/patent/[4369901](/patent/4369901) ; https://patents.searchlight.law/doc/US4369901

(B) Express criticism of a reference by another reference — the Sauer → Lewis line.
US4580687A (Lewis) describes a known prior-art cap "manufactured by C. F. Sauer Company" with "a raised circular platform to which a closure is attached by means of a continuous 'living' hinge," acknowledges that the raised platform "may contribute to cap strength; it also enables one to get a fingernail … under the closure," and then criticizes it on stackability. The Sauer cap is the very subject of US4494679 in the '399 citation list. Lewis also states the object and the means: "characterized in that the bottom surface of the closure is coplanar with the upper surface of the cap when the closure is shut." Again — express, articulated cross-reference between two cited references.

(C) Express teaching of the operative mechanism — the Kraft line.
US4545508A (Kraft) does not merely disclose a two-mode hinged-lid closure; it expressly teaches that lid 40 can be released by distortion of the lid itself: upward pressure "will … distort the lid 40 by elongating it along the axis of hinge movement, while compressing its diameter in a transverse direction, such that the tongue-in-groove fitment is readily released." It also expressly frames the cooling/shrinkage problem: reinforcing braces terminate at ridge 77 "so as not to interfere with the maintenance of a smooth circular shape of the opening, upon cooling of the organopolymeric material," maintaining a fit "without preferential shrinking."

(D) Express teaching of the operative mechanism — the Continental line.
US4463869A (Continental Plastics / Lewis) teaches the front portion of cover 71 "will flex along groove 83, while the main portion of the cover remains in closed position, by engagement of locking lip 79 with a wall 81 of aperture 61, until the front portion is sufficiently raised to provide a grip." That is the partial-release-while-remainder-latched behavior that claim 9 recites as "peeling."

(E) A cross-citation network among the nine. Two independent citation lists corroborate that these references were regarded as one art:

• US4580687A's References Cited includes 4,494,679 (Cleevely / Sauer — i.e., US4494679A) and "4,561,250 … Foster" (see Part 0, contradiction #2).
• J.L. Clark's D301549 (Foster) cites US4361250 (Foster), US4463869 (Lewis), US4280636 and US4359171 (Lewis), US3542235 (Hidding), US3322308 / US3675812 (Foster), US3155285 (Van Baarn), US4658980 (Lindstrom).
  Source: https://patents.justia.com/patent/D301549

(F) All references are analogous art in the same field of endeavor. Every one is a container closure for dispensing a pourable/siftable product from a container mouth: US3493150A (package closure), US4163496A (dispensing small objects — confectionery), US4361250A (plastic container closure for a spice can), US4369901A (spice dispenser), US4463869A (spice can lid), US4494679A (closure for dispensing solids), US4545508A (grated cheese), US4580687A (powder/crystalline dispensing cap). Under In re Bigio / In re Clay, this is the same field and the same problem — no field-of-invention hurdle.

(G) Market-force / design-incentive motivation, stated in the '399's own background. The '399 specification's own recitation of the problem — that the spoon opening "has been limited to less than half of the mouth opening of the container," which "can be inconvenient … in commercial establishments and institutions where relatively large spoons are used," and that prior-art closures used "a rib on the spoon flap parallel to the hinge that functions to stiffen the flap" which "obstruct[s], and thereby lessen[s], the effective size of the spoon aperture" — is itself a statement of design incentives and a known problem in the field, which KSR holds supplies the motivation without more.

(H) Reasonable expectation of success. All nine references are injection-molded thermoplastic closures; several are expressly polypropylene (US4580687A; US3493150A lists polypropylene among spin-weldable thermoplastics) with living hinges (US4580687A; US4163496A; US4369901A). The combination is a substitution of known retention hardware (plugs/tangs/lugs) into a known two-mode hinged-flap cap — a predictable mechanical substitution, not an unpredictable one.

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Part 3 — Combination-by-combination claim analysis

Claim 1 — spaced catch means extending ≥ half the spoon-flap free edge

Combination C‑1: US4369901 (Hidding) + US4361250 (Foster) [+ optionally US3217949 (Davis)].

Motivation. Hidding expressly identifies the shortcomings of the closest two-flap spoon/sifter closure (Davis US3217949): both flaps can be raised simultaneously, and hinge springiness biases the flaps away from fully open. A POSITA addressing "flap does not stay reliably closed over the wide spoon opening" would look to the most directly analogous closure art — Foster's single-flap spice-can closure, whose stated express purpose is "augmenting the hold-down action of the lugs 21 and … securely locking the flap 16 downwardly … to prevent the flap from accidentally popping open during shipment." Foster teaches precisely the remedy: distribute the hold-down along the aperture edge rather than relying on a single lip or a pair of protuberance/niche snaps. Substituting Foster's lugs-on-rib for Hidding's protuberance/niche lock is a predictable substitution of one known snap-retention expedient for another in the same field, with the expected result of more uniform retention. The "≥ ½ of the free edge" limitation is met by Foster's lugs distributed "along part of the rib" whose length follows the aperture edge, and, independently, by US4163496A's transverse ridge 24 whose "length equal[s] the width of the tongue."

Confidence: Moderate-to-high on motivation; moderate on the ≥ ½ quantitative limitation, which is a matter of degree that the prior section was right to call the claim's principal point of novelty.

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Claims 2, 3, 4 — catch geometry and arc extent

Combination C‑2 (same as C‑1).

• Claim 2 ("discrete elements spaced from one another") — US4361250's "Short lugs 21" (plural, discrete) on rib 20. In re Kauffman / KSR: selection of discrete versus continuous fastening elements is a design choice yielding no unexpected result; both perform the same function of locally engaging an aperture edge.
• Claim 3 (catch length < spacing) — pure dimensional optimization of a result-effective variable. Foster's lugs are expressly "short" relative to the rib on which they are spaced. No criticality is asserted in the '399 specification for this ratio.
• Claim 4 (catch means subtend an arc > 90°; 120° preferred) — the '399 specification supplies no criticality beyond "has been found to provide satisfactory retention." Where a cap's aperture is a circular arc and secure retention requires engagement across the flap's width, spreading catches over a major fraction of that arc is the predictable, if not compelled, design choice; US4369901's spooning opening 34 is a sector-shaped opening and US4580687A's flap/opening is a major arc, so the artisan is working in arcs by construction.

Confidence: High on claims 2–4 as obvious design choices.

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Claims 5–8 — catch placement on the anti-sift skirt

Combination C‑3: US4369901 (Hidding) + US4361250 (Foster).

• Claim 5 (catches engage an edge of the spoon aperture) — US4361250: lugs 21 "engage the edge of the opening 15 with a releasable snap fit." Direct teaching.
• Claim 6 (flap marginal area extends outwardly of the aperture) — US4361250: recess 18 "similar in shape to the flap and its bottom defines an upwardly facing platform 19 upon which the flap rests when the flap is closed," with the flap overlying the opening. US4580687A teaches the corresponding flush/coplanar marginal seating ("the bottom surface 42 is coplanar with the top surface 44 of the cap").
• Claim 7 (thin skirt cooperating with the spoon aperture to avoid sifting) — US4369901: spooning cap 40 is "fashioned with a pendant, internal skirt 48 which sealably fits in the spooning opening 34." Verbatim function.
• Claim 8 (catches disposed on the thin skirt) — US4361250: the lugs 21 "are molded integrally with part of the rib" — i.e., the catches are on the depending skirt, not on the flap body. This is the exact claim‑8 architecture.

Motivation. Both references address the same anti-sift/seal problem: Hidding's skirt 48 "sealably fits in the spooning opening"; Foster's rib 20 "telescope[s] into and seal[s] the opening." Providing catches on that same skirt (rather than on a separate feature) is the mechanical expedient of using an already-present structure for a second function — precisely the kind of "combination of familiar elements according to known methods" that KSR holds obvious, and which the '399 specification itself treats as an advantage (the thin lip 24 "is relatively small in cross section to avoid significant flexural stiffening").

Confidence: High. Claims 5–8 are the strongest §103 targets in the patent.

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Claim 9 — thin, un-stiffened, peelable flap with a plurality of individual catches

Claim 9 is the claim the prior section correctly identified as the "core" claim, and it is where the §103 case is most contestable. Here is the honest version.

Combination C‑4: US4545508 (Kraft) + US4361250 (Foster) + US4463869 (Continental).

Motivation. (i) Problem recognition is in the references. US4545508 expressly addresses cooling-induced "preferential shrinking" and the need to maintain a "smooth circular shape of the opening"; the '399 states the same problem in its background (ovality from the asymmetric absence/presence of plastic stock around a large spoon aperture). A POSITA addressing "retention forces drift with molding variation" is directed by US4545508 to rely on flap compliance rather than on a rigid, high-interference fit. (ii) Trade-off management is in the references. US4361250's stated objective is to maximize hold-down for shipment; US4463869's is to let the cover flex so the user can "sufficiently raise[]" a front portion. A POSITA seeking both high total retention and low opening effort would naturally arrive at what the '399 calls peelability — a plurality of catches that can be released progressively rather than simultaneously — because the two cited objectives can only be reconciled by distributing the retention and permitting flap flexure. (iii) Mechanical consequence. Once plural spaced catches are combined with a flap thin enough to flex (US4463869, US4545508), release of "fewer than all of the catches … at any given time" is an inherent mechanical result, not a separate inventive act. For an apparatus claim, an inherent property of the claimed structure is met by the prior-art structure, and the presence of a new reason for making an old structure does not confer patentability. Source for the Kraft teaching: US4545508A text (verified in the prior-art section); Continental via US4463869A text.

The counter-argument the analyst must not suppress — an express teaching away.
US4163496A (P. Ferrero & C.) — a reference on the face of this patent — goes out of its way to require rigidity: "The thickness of the tongue 14 is chosen … to be such that the tongue is sufficiently rigid that it does not bend under the action of the forces exerted on it during the operations of opening and closing"; and it justifies the design on that basis: "the stiffness of the tongue 14 due to its thickness … prevents the tongue 14 itself from being deformed under the action of the forces imparted … during the opening operation, in which the axial component of the thrust exerted by the thumb would tend … to bend this upwardly." That is a purposive teaching that flap deformation is undesirable — the opposite of claim 9. A well-briefed patent owner will lead with this.

How a challenger answers it. (a) A teaching away is only probative if it would have discouraged a POSITA from the claimed combination; US4163496A's rigidity requirement serves a different purpose — maintaining a "perfect seal" between two separately sealed chambers against aroma transfer. Claim 9 is a two-mode spoon/shake cap, not a partitioned aroma-barrier container, so the reference's reason for rigidity does not reach the claimed context. (b) The art is split, and the '399 sets are contemporaneous: US4545508 (1985) and US4463869 (1984) both rely on flap flexure/distortion. Where references in the same field point in opposite directions, KSR instructs that the reference teaching away must be weighed, not treated as dispositive. (c) The rigidity of US4163496A's tongue is achieved by a transverse ridge 24 — i.e., exactly the "heavy stiffening rib" the '399's background disparages as obstructing the spoon aperture. That gives an independent structural motivation to omit it: doing so preserves the effective spoon aperture area.

Confidence: Moderate. This is the claim where a §103 case is arguable both ways, and where US4163496A is genuine ammunition for the patent owner.

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Claim 10 — spoon-flap version of the peelable catch arrangement

Combination C‑5: US4545508 + US4361250. Claim 10 merely relocates claim 9's catch means to the spoon flap and specifies they "engage the edge of said spoon aperture." US4361250's lugs 21 engage "the edge of the opening 15" — verbatim. Motivation identical to C‑1/C‑4: the reason to distribute catches across the widest flap (the spoon flap) is strongest there, since retention force scales with catch count and the spoon flap is the largest. Confidence: moderate-to-high.

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Claim 11 — shake-flap plug elements with catches engaging the small apertures

Combination C‑6: US4580687A (Lewis) and/or US3493150A (P&G) + a two-mode base (US3217949 Davis, US4369901 Hidding, or US4494679 Sauer).

This claim is close to the heart of the now-verified material.

• US4580687A discloses plugs 50 depending from the closure's bottom surface at locations corresponding to the holes, each with "a conical base 52 and a cylindrical tip 54 sized to fit closely within its respective hole," the outer plugs each having "a small tang 56 thereon to retain the tip within its hole and to provide the closure with a positive snap action when opened or closed." That is catch means on plug elements adapted to engage small apertures — literally claim 11's structure.
• US3493150A discloses plugs comprising "an upper cylindrical portion, a central cylindrical portion of slightly larger diameter than the upper cylindrical portion" (i.e., an undercut/gripping shoulder), "and a lower frustoconical portion tapering downwardly inward" (a camming surface), with specified ones being "releasably interlocking" and "telescoped within" the apertures — and the apertures are "eccentrically positioned."
• US4369901 and US4494679 supply the two-mode base: Hidding's "tubular posts 50 [which] sealably penetrate the tapered holes 36"; Sauer's "projections 35" which "frictionally engage[e] the walls about the apertures."
• Eccentricity. The '399 places catch 47 "on an axis eccentric from the axis of the associated plug 43 so that they exist only on a side of the plug remote from the hinge." US3493150A recites "eight eccentrically positioned apertures." The artisan's reason for eccentricity is transparent in both: leave the hinge-side of the plug unobstructed so the plug can tip freely into its hole without the catch fighting the hinge's arc. That is a design choice with a stated functional rationale, and the '399's own specification gives no criticality beyond ease of closure.

Motivation. The plug-in-aperture seal is the standard way in this art to stop sifting through a shaker web (Hidding's posts 50 "sealably penetrate the tapered holes 36"; Sauer's projections "frictionally … releasably retain"). Once a plug already sits in each hole to stop sifting, adding a retaining shoulder/tang to that same plug is the mechanical expedient of giving an already-present structure a second function — and the references supply the exact geometries (Lewis's tang 56, P&G's enlarged central cylindrical portion). The expected result — a sift-tight plug that also holds the shaker flap closed — is exactly the stated purpose of the '399's catch 47.

Confidence: Moderate-to-high for the structure; high that a POSITA would look to plug-carried catches, since both verified references do it in a shaker-hole context.

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Claim 12 — chordal land coplanar with the annular sealing ledge to support a liner shell

Combination C‑7: US4580687A (Lewis) + US4494679A (Sauer) + a liner-seat reference outside the citation set.

Honest assessment. This limitation is the subject of explicit, first-hand contrary judicial comment, and I will not paper over it. The prior section records the district court's identification of the coplanar land/ledge as one of "the most important features" of the claim — that is a non-obviousness signal, not an obviousness one. The best §103 theory available is: (i) a screw cap intended to receive a foil/paper innerseal necessarily has a flat annular seat; (ii) a land between two hinged flaps must be at least at the elevation of the flaps' closed undersides to receive them; and (iii) making that land's lower face coplanar with the seat so a single stamped liner can bear on both is an obvious mechanical expedient once the designer decides to use a stamped liner — which is the '399's own stated reason ("this land area can provide support for intermediate areas of a paper seal … particularly important when the seal is stamped into the closure by automatic high speed equipment"). A rationale that appears in the patent's own specification as a manufacturing convenience is weak material for non-obviousness.

Confidence: Low. Flagged as the weakest independent claim on §103, together with claim 13.

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Claim 13 — flat sealing ledge extending radially ≥ 2× nominal wall thickness

Combination C‑8: same as C‑7. No reference in the citation set expresses any radial dimension of a sealing ledge. The case is:

• Design choice / result-effective variable. The stated purpose is that the cap "will produce a reliable seal on the mouth of a container … despite any expected degree of ovality." Widening a flat sealing land to accommodate expected out-of-roundness is optimizing a result-effective variable by enlarging the variable, with a predictable result. US3493150A corroborates that closure wall dimensions were routinely designed to a purpose ("sufficient rigidity to withstand the forces … which may range from 1 pound to ten pounds"), and its design wall profile (.035 in center → .090 in periphery) shows thickness/length dimensions as free design levers.
• No criticality asserted. "Substantially equal to at least twice the nominal wall thickness" is a range; the specification offers no data showing a seal failure below 2× and success above.
• Counterweight. The claim was allowed, and the district court declined to find it obvious. The numerical "at least twice" limitation is exactly the kind of limitation that resists a KSR challenge absent a reference.

Confidence: Low. I would not build a §103 invalidity contention on claim 13 alone.

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Claim 14 — thickness at the ends of the chordal land substantially less than the average land thickness (freeze points)

Combination C‑9: US4545508 (Kraft) + general injection-molding knowledge. This is the weakest §103 case in the patent.

• Problem stated in the art: US4545508 addresses "preferential shrinking" and "maintenance of a smooth circular shape of the opening, upon cooling of the organopolymeric material." The '399's background states the identical problem.
• Means: the claimed structure is a wall-thickness differential at a defined location (the two ends of the chordal land). US3493150A evidences that designers deliberately varied wall thickness across a single molded closure to achieve a functional result (.035 in center, .090 in periphery), so thickness-as-a-design-lever is known.
• Obvious to try: the claimed solution belongs to a small, predictable set of remedies for differential shrinkage in a molded part (vary section thickness; relocate the gate; balance plastic mass). KSR holds that where a problem is known and the solutions are finite and predictable, "obvious to try" defeats patentability. Claim 14 also recites the mechanism of action ("freezes at a relatively early stage in a molding cycle to reduce the tendency … to assume an oval condition"), which for an apparatus claim is not a structural limitation that can supply patentability.
• But: no reference in the citation set discloses thin end zones on a chordal land, and none frames wall-thickness reduction as a freeze-point strategy. The specified location (the two ends of the land — the points of greatest structural discontinuity in the part) is a non-trivial specificity.

Confidence: Low-to-moderate. Arguable, not compelling.

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Claim 15 — recess around the gate vestige, deep enough to keep the vestige above surrounding land areas

Combination C‑10: US4580687A + the liner-seat art of C‑7. Claim 15 is a dependent claim directed to a pure molding-envelope design choice: recess the gate area so the broken vestige does not protrude above the sealing surfaces (and therefore cannot puncture the liner). The '399's own specification frames it exactly as a design precaution — "there is no risk that a circular paper seal … will be punctured by the vestige." Under KSR's design-choice line and In re Harza (enlarging/recessing for an identified functional reason), this is obvious once a liner-receiving cap with a central gate is the starting structure.

Confidence: Moderate (against claims 12/13's dependencies; not independently viable, since claim 15 depends from claim 14).

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Part 4 — §103 matrix

Headline result: a credible §103 challenge exists against claims 1–11, with claims 2–8 and 11 the strongest, and claim 9 genuinely contested. Claims 12–15 are weak on this citation set — the section should say so plainly rather than manufacture a combination.

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Part 5 — Objective indicia and the contrary record

The single most important fact for this section: the district court, in the same proceeding that invalidated the patent, made an alternative express finding that the '399 patent was NOT obvious — a finding the Federal Circuit did not disturb, because it affirmed on the on-sale bar and mooted the rest. Any §103 opinion that does not lead with this is misleading. The prior sections correctly state this and I am not contradicting them; I am emphasizing that the record on obviousness for this patent is judicially adverse to the challenger, even though the patent is dead.

Objective indicia, honestly weighed:

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Part 6 — Contradictions and unresolved items (flagged, not smoothed over)

1. Claim-level scope of the 1998 judgment. The earlier "Litigation history" section says the Federal Circuit modified the judgment to cover only claims 12 and 13; the earlier "PTAB challenges" section says the district court held "the '399 patent is invalid" as a whole and that no claim-by-claim cancellation exists. A third phrasing appears in the "Prior art" section. These remain in tension. For §103 purposes: claims 1–11, 14, and 15 were never adjudicated for validity or obviousness — which is why the §103 analysis above has to be performed at all, rather than being foreclosed by judgment. Whether those claims are also invalid under the same §102(b) on-sale activity is a §102 question outside this section's scope.

2. The prior-art section's characterization of US3493150A. That section called it "unlikely to be the closest art on claims 1/9/12/13/14" and "peripheral." Now that its claim 4 plug geometry is verified, it is not peripheral as to claims 9 and 11, though it remains peripheral as to the two-mode preambles. This is a correction, not a contradiction in substance.

3. "4,561,250 … Foster" on US4580687A. Presented literally per the no-auto-correction rule. Do not silently treat it as US4361250A in any filed paper without checking the granted copy.

4. Design application vs. continuation-in-part for US 899,935. The litigation material calls it a design application; Google Patents styles it a "Continuation-In-Part." Unresolved in the earlier section and unresolved here. It matters to §103 only indirectly — the district court held it did not satisfy §112 ¶1 for the claimed invention, which is why the critical date is 1985‑10‑17.

5. US4580687A's prior-art status. It published 1986‑04‑08, after the 1985‑10‑17 critical date, so it is not §102(a)/(b) art; it is available only as §102(e) art as of its 1984‑12‑31 filing date (and pre-AIA §102(e) art is usable in §103). If the '399 could carry its invention date back before 1984‑12‑31 — which the record does not support, the drawing being dated 1985‑02‑08 — this reference would drop out. Every combination above that leans on US4580687A (C‑1's D-flap geometry, C‑6, C‑7, C‑10) inherits this vulnerability.

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Part 7 — Bottom line

1. The citation set supports a viable §103 attack on claims 1–11, and does not support one on claims 12–15. The strongest combinations are:

   • US4369901 + US4361250 → claims 1, 5, 6, 7, 8 (two-mode spoon/sifter closure + distributed lugs on a depending skirt engaging the aperture edge);
   • US4545508 + US4361250 + US4463869 → claims 9, 10 (distortable thin lid + plural lugs + flex-while-latched);
   • US4580687A and/or US3493150A + US4369901 or US4494679 → claim 11 (plugs with conical camming lead-in plus tang/undercut engaging the shaker holes).

2. The motivation to combine is unusually well documented, because the references criticize each other and cite each other. US4369901 expressly criticizes Davis US3217949's two-flap closure (flaps pop open; springiness resists full opening). US4580687A expressly describes and criticizes the Sauer raised-platform cap that is the subject of US4494679. US4545508 and US4463869 each expressly teach flap distortion/flexure as the release mechanism. Under KSR that is articulated reasoning with rational underpinning, not hindsight.

3. The genuine obstacle is US4163496A's express rigidity requirement — a reference on the face of the '399 that says the tongue must be "sufficiently rigid that it does not bend." It is answerable (different purpose — partitioned aroma barrier, not peel-open spoon cap; art is split; its rigidity comes from the very stiffening ridge the '399 disparages), but it is a real teaching away and the patent owner's best §103 argument.

4. Do not overstate claims 12–15. Claim 12's coplanar land/ledge liner support and claim 13's ≥ 2× radial ledge have no disclosure support anywhere in the nine references; claim 14's thin end zones have none either. For those claims, the effective invalidity theory is the §102(b) on-sale bar that actually killed them — a ground that is statutorily unavailable in an IPR under 35 U.S.C. § 311(b) — not §103.

5. The record cuts against the challenger in one specific way that must be disclosed: the district court made an express alternative finding that the '399 patent was not obvious, and the Federal Circuit did not reach it. Any §103 opinion should state that finding and explain why it does not bind on a combination the court did not consider — or advise against filing on claims 12–15 at all.

Residual uncertainty. (a) I did not retrieve USD278602 or US3140019A/US3255907A/GB1178362A/NZ183806A, so the C‑7/C‑8 liner-seat theory rests on references outside the '399 examination record and is unverified in detail. (b) The "4,561,250 … Foster" identifier on US4580687A is reported as printed. (c) All §103 conclusions here are analytical; the only judicial determination of obviousness in this patent's history is the district court's negative one, and it was not reviewed on appeal.