US 7631682

I'll verify the patent's current status and check for any litigation or CAFC activity, then summarize.

US 7,631,682 B2 — Verification and Summary

Important caveat up front: I do not have direct API access to USPTO PatentCenter or the CAFC docket system. What follows is drawn from live web-search results (principally the Google Patents record, which mirrors USPTO bibliographic data, plus FreePatentsOnline/Justia) and the authoritative full text you supplied. See the "Uncertainty" section below for what I could not confirm.

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Bibliographic data

Assignment recorded Sept. 25, 2007 (Reel/Frame 019873/0863), assignors Lamers, Wetsema, and de Lange to Hunter Douglas Industries BV, with signing dates Apr. 3–17, 2007.

Term note: Google Patents displays an "adjusted expiration" of 2027-12-30, reflecting the nominal 20-year term measured from the July 2007 filing (plus adjustments). That figure is not the operative expiry here — the record shows the patent actually lapsed in December 2013 for non-payment of maintenance fees.

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Abstract (verbatim from the record)

"A retractable window covering that has a flexible fabric panel having a bottom edge with a weight bar attached to it. The fabric panel has one or more elongate pockets across its width, accommodating a length-expanding stiffening rod with: an elongate guiding element of non-magnetic material; a first magnet guided for movement along the elongate guiding element; and a second magnet guided for movement along the elongate guiding element and positioned in respect of the first magnet, so that the first and second magnets repulse one another and the guiding element limits and guides the movement of the first and second magnets in respect to one another."

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The independent claim, in plain language

The patent has 4 claims total — one independent claim (claim 1) and three dependent claims (2–4). A point worth flagging: claim 1 as granted is drafted somewhat differently from the "BRIEF SUMMARY" paragraph in the specification. The summary describes the rod in terms of an "end element"; the granted claim instead recites the telescoping structure explicitly. Practitioners should treat the claim language, not the summary, as controlling.

Claim 1 — A retractable window covering comprising:

• a support member (head rail) mountable to a building surface;
• a flexible fabric panel with a first edge fixed to the support member and a second edge hanging down;
• a weight bar on that lower edge;
• a retraction mechanism at the support member for raising/lowering the weight bar (thereby retracting the panel);
• the fabric panel has at least one elongate pocket across its width holding a length-expanding stiffening rod;

and the characterizing part — the stiffening rod itself comprises:

• an elongated member with an open end and a hollow interior (the tubular body 25);
• an elongated guiding element (shaft 29) having a large outer diameter at one end that slides inside that hollow interior, and a relatively smaller outer diameter at the opposite end protruding out of the open end;
• a pair of magnets fitted on the smaller-diameter portion, at least one of which is slidable along it;
• the guiding element has a resilient enlarged end on the smaller-diameter portion that lets the magnets be slipped on and then retains them;
• the net effect: the magnets bias the guiding element axially outward of the elongated member's open end, while still permitting the guiding element to be yieldingly pushed back in (compressed for insertion into the pocket).

In short: two repelling magnets replace the conventional compression spring, using magnetic repulsion as the length-expanding/bias element, with the shaft acting as the guide and retainer.

Dependent claims:

• Claim 2 — the first and second magnets each have a central aperture engaging the shaft.
• Claim 3 — each magnet is annular in shape.
• Claim 4 — the retraction mechanism uses lift cords to retract the panel.

The specification adds that the guiding element is preferably non-magnetic, that the two magnets are preferably identical (for simplified stock-keeping), and that they are preferably rare-earth magnets of neodymium-iron-boron, chosen for high energy and coercivity. The stated motivation is that coil springs required careful matching of spring force to different fabrics and caused unsightly fabric deformation, whereas magnetic repulsion gives a moderate, self-adjusting expansion force without a spring that could snag fabric interstices.

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Litigation / CAFC 2026 docket check

I searched for CAFC and litigation records tied to 7631682. No CAFC appeal, district court action, or PTAB proceeding involving US 7,631,682 was found. Consistent with that, the patent lapsed in 2013 for fee non-payment, and there is no post-issuance assignment or reexamination in the legal events.

One caution on methodology: the query for "7631682" combined with CAFC/ Federal Circuit surfaced a hit for US 4,775,239, which discusses a German utility model "No. 76 31 682." That is a different identifier (a German Gebrauchsmuster number, not the subject US patent) and is not a result for US 7,631,682. I am flagging it rather than silently discarding it, per the literal-interpretation rule. Note also that the patent family listing references the spring prior art as "DE G 83 18 292 U1" in one place and "DE 8312292" in another — I have not reconciled which rendering is correct.

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Statement of uncertainty

• Not authoritatively confirmed: I could not independently query USPTO PatentCenter or the CAFC docket interface. The absence of litigation/CAFC results is based on web-search coverage, not a guaranteed-complete docket check. Treat "no CAFC activity found" as "none surfaced," not as a certified negative.
• Status date: the "Expired – Fee Related" status and the Dec. 15, 2013 lapse effective date come from the Google Patents legal-events mirror of USPTO records. I did not verify against PatentCenter directly.
• Controlling claim text: the granted-claim wording differs from the specification's summary passage; I have summarized the granted claim as published. If a claim-construction analysis is needed, the full prosecution history (not available to me here) should be reviewed.
• Assignee currency: the record shows Hunter Douglas Industries BV as both original and current assignee, with no subsequent recorded transfer. I cannot rule out unrecorded corporate changes.

I'll research whether US 7,631,682 has been involved in any patent litigation. Let me run several targeted searches.

Let me search patent-litigation-specific databases for this patent number.

Litigation Search: US Patent No. 7,631,682

Bottom line

I found no litigation involving US 7,631,682. Searches of litigation-focused sources returned no case in which this patent was asserted in a district court action, ITC investigation, PTAB proceeding, or Federal Circuit appeal. I cannot, however, prove a universal negative — see the "confidence/limits" note below.

What the patent is

For context on why this is unsurprising:

• Title: "Retractable window covering having a length expanding stiffening rod"
• Patent no.: US 7,631,682 B2
• Application: 11/778,774, filed 2007-07-17
• Priority: 2006-07-21 (EP 06015275.8)
• Assignee: Hunter Douglas Industries BV (original and current)
• Inventors: Franciscus Cornelis Gerardus Lamers; Jan Pieter Wetsema; Hans de Lange
• Publication: US 2008/0017327 A1 (2008-01-24); granted 2009-12-15
• Claim scope: 4 claims directed to a retractable window covering (e.g., roman shade) with a fabric pocket holding a length-expanding stiffening rod in which two repelling magnets on a non-magnetic guide shaft bias the rod outward.
• Legal status: Expired – Fee Related. The maintenance-fee lapse trail on the face of the record is: maintenance-fee reminder mailed 2013-07-26; lapse for failure to pay 2013-12-15; patent discontinuation recorded 2014-01-10/2014-01-13; "Lapsed due to failure to pay maintenance fee," effective 2013-12-15. The adjusted-expiration entry of 2027-12-30 in the Google Patents header reflects the nominal maximum term had fees been paid, not the actual current status.
• Family: ATE473348T1, DE602007007547D1, ES2347983T3, and EP1881148B1 (the European counterpart)

A patent that went abandoned for non-payment of maintenance fees in 2013 and that claims a narrow mechanical shade-stiffener detail is a low-probability litigation asset, which is consistent with the null result.

What I searched and what I found

Note: Patent 7,631,682 does appear in the citation graph — it is cited by later patents (e.g., US 2011/0083814 A1, US 8,590,591 B2, and various vertical-blind/magnetic-curtain filings) and itself cites earlier art such as US 3,467,973 (magnetic spring/shock absorber), US 3,487,875, and DE 83 18 292 U1. Citation is not litigation, and I did not treat any citational hit as a lawsuit.

Confidence and limits — please read

• Not exhaustive. I could not exhaustively query PACER directly or complete a full docket-level sweep within this session. A PACER/Unified/RPX/Docket Alarm "all cases" pull keyed to the exact number would be the definitive check the user requested.
• Strict-number discipline applied. I excluded results for near-neighbors that are easy to confuse, notably US 7,631,065 (Amdocs v. Openet), US 11,286,168, German G 76 31 682, and Hunter Douglas's '131 / '196 / D456,196 patents. None of those are US 7,631,682.
• One search call returned an error (step limit reached), so the final Unified Patents litigation-query attempt did not complete. This does not change the overall finding, since all completed searches were negative.

If you need certainty

I'd recommend running the exact number through:

1. PACER (all district courts) — search "7,631,682" as a patent-in-suit;
2. Unified Patents Portal — https://portal.unifiedpatents.com/litigation/ and its PTAB case list (searching "7631682");
3. RPX Insight and Docket Alarm / CourtListener full-text complaint search;
4. USPTO PTAB (Application/Patent Number search) for any IPR/PGR/CBM;
5. Federal Circuit docket search for any appeal naming the patent.

Stated plainly: based on the searches performed, no litigation involving US 7,631,682 is known. I could not identify any plaintiff, defendant, jurisdiction, case number, filing date, or outcome because no such case was found.

I'll verify the structured "no proceedings" signal against live sources before writing the analysis.

Let me run a couple more targeted checks before concluding.

Proceedings overview

Zero AIA trial proceedings on file. The structured PTAB block — sourced from the USPTO Open Data Portal — returns no IPR, PGR, or CBM for US 7,631,682, and independent web checks surface no PTAB petition, Final Written Decision, or Federal Circuit appeal involving this patent number. The defensive posture is therefore not "hardened by survived IPRs" but rather "no one ever bothered to attack it at the Board, because the patent died of its own accord": US 7,631,682 lapsed on 2013-12-15 for failure to pay the maintenance fee due at 3.5 years, per the recorded legal events (LAPS, FP — "PATENT EXPIRED DUE TO NONPAYMENT OF MAINTENANCE FEES UNDER 37 CFR 1.362"). A defendant facing a demand letter citing this patent should lead with expiry, not with invalidity.

Two sources of confirmation, both worth citing if you need to paper a file:

• The Google Patents record for US7631682B2 carries no "PTAB" or "AIA Trial" section at all — Google's scrapers populate that section when proceedings exist, and it is empty here.
• USPTO PTAB case search (now PTACTS, https://ptacts.uspto.gov/ptacts/; the legacy PTAB E2E portal is retired) returns nothing for the patent number. I could not query the ODP API directly from this session, so this rests on search-surfaced records plus the structured block — treat it as high-confidence but not a substitute for a docket printout.

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No proceedings to itemize

Because the canonical list is empty, the per-proceeding template below has nothing to populate. For completeness, the null findings that matter:

• Type: N/A — no Inter Partes Review, no Post-Grant Review, no Covered Business Method review.
• Filed: N/A.
• Status: N/A.
• Judge panel: N/A — no APJs ever assigned.
• Petition grounds: N/A.
• Institution decision: N/A — no institution decision, no denial.
• Final Written Decision: N/A — no claim of US 7,631,682 (claims 1, 2, 3, 4) has ever been adjudicated at the Board. Do not assume any claim is canceled. The patent's claims remain presumptively valid; validity was merely never tested in an AIA trial.
• Settlement / termination: N/A.
• Appeal: N/A — no CAFC docket and no CourtListener entry for an appeal of this patent.
• Defensive value: Limited as an invalidity story, decisive as an enforceability story. See below.

Also excluded by the procedural posture: PGR is unavailable (patent has an effective filing date of 2007-07-17, pre-dating 2013-03-16). CBM is unavailable — the patent's claims are directed to window-covering mechanics, not a "financial product or service," and the CBM transition window closed 2020-09-16. That leaves IPR as the only AIA vehicle, and only if you actually need one.

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Strategic summary

Claim status: everything is UNTESTED, and that is now largely academic. US 7,631,682 issued 2009-12-15 with four claims: independent claim 1 (the retractable window covering with the magnet-repulsion stiffening rod) and dependent claims 2–4 (2: magnets with central apertures engaging the shaft; 3: annular magnets; 4: lift-cord retraction mechanism). No PTAB proceeding ever touched them. But the maintenance-fee lapse recorded at 2013-12-15 means the statutory term was cut short roughly ten years before the 2027-12-30 adjusted expiration that Google Patents still displays for term-calculation purposes. That figure is an adjusted term — the date the patent would have run had fees been paid — and it is flatly inconsistent with the intervening LAPS and FP legal events. Treat the patent as expired since 2013-12-15. If you want to be rigorous, run an ODP "Application/Patent Status" query and a 37 C.F.R. § 1.378 reinstatement check; the source record here shows no petition to reinstate, and I found none on search.

Estoppel landscape: none exists. Because there has been no IPR, there is no § 315(e)(2) estoppel running against any party, and no prior petitioner is barred from raising anything. If you are the first challenger, the entire prior-art universe is open to you — but you should think hard before using it. Under pre-AIA 35 U.S.C. § 286, a patentee can recover damages only for infringement occurring within six years before suit. With the patent expired since 2013-12-15, the recovery window on this patent would be, at the very most, infringement from roughly late 2007 through 2013-12-15 — conduct at the very start of a product's life cycle, and which the patentee would already have had to have been diligently pursuing. Practically, the demand letter is worth less than the paper it arrived on.

Pattern signals: there is no pattern, and its absence is itself the signal. Hunter Douglas Industries BV is a sophisticated, serial patent enforcer — the same corporate family litigated the '242 patent against Great Lake Woods through a bench trial in D. Colo. (Case 1:15-cv-00106-REB-KLM, findings filed 2019-03-27) and has been on the receiving end of IPRs on other patents (e.g., IPR2014-01175 on US 6,968,884, where Hunter Douglas took an adverse judgment by statutory disclaimer). This patent got none of that attention. It was allowed to lapse in its fourth year and has never been asserted in any reported litigation I can locate. No defensive aggregator (Unified Patents or similar) appears anywhere in the chain. The European counterpart EP1881148B1 (which survived to 2010-07-07) is the only family member with a substantive prosecution history of note.

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Recommended next steps

1. If you hold a demand letter citing US 7,631,682, lead with expiry and inspection of the patent's fee history. Quote the USPTO legal event verbatim: "PATENT EXPIRED DUE TO NONPAYMENT OF MAINTENANCE FEES UNDER 37 CFR 1.362," effective 2013-12-15. Confirm the current status via https://patents.google.com/patent/US7631682/en (legal events section) and, independently, through USPTO Patent Center (https://patentcenter.uspto.gov/) — do not rely on Google's stale "expires 2027-12-30" line, which reflects an adjusted-term calculation, not the operative status.
2. Because there is no FWD, there is no opinion to quote and no disposition to link. Any invalidity argument you mount is a first-instance argument: file it in district court under §§ 102/103/112, or (if you genuinely need PTAB cover) as a de novo IPR — noting that IPRs on expired patents are permitted, but the cost/benefit here is poor given the § 286 damages ceiling.
3. Do not import another Hunter Douglas patent's history into this one. The D. Colo. judgment, the '884 patent disclaimer, and the IPR2014-01175 adverse judgment all concern different patents. Asserting that US 7,631,682 "survived" anything, or that any claim of it was "held invalid," would be a fabrication.
4. Check the enforcement chain against your own product timeline. If the accused conduct post-dates 2013-12-15, there is no infringement of this patent as a matter of law — the claims cannot be infringed after expiry. Only pre-expiry conduct is actionable, subject to the six-year § 286 bar and laches-type equitable defenses.
5. Verify independently. My searches could not reach the ODP API directly. Before relying on the zero-proceeding finding in a filing, pull a PTACTS docket printout (https://ptacts.uspto.gov/ptacts/) and, if relevant, a Docket Navigator or CourtListener query for any unindexed inter partes challenge or state-court action.

Confidence note: I am highly confident there are no AIA trials on this patent, and highly confident the maintenance-fee lapse is recorded. I have not verified whether a § 1.378 reinstatement petition was ever filed and granted — the returned record shows none, but I would not stake a filing on that absence without a live status check.

I'll verify the assignment record and assignee status before writing this up.

Assignment & Ownership Reconstruction — US 7,631,682 B2

Verification note / limitation up front: My tooling for this run returned indexed web sources, not a live query of the Assignment Center UI. The reel/frame identifier and legal events below are taken from the USPTO assignment record as reproduced in the patent's authoritative record (Google Patents "Legal Events" + "Assignment" entries, source: https://patents.google.com/patent/US7631682/en). Independent confirmation is available by searching patent number 7631682 at https://assignmentcenter.uspto.gov/ (legacy equivalent: https://assignment.uspto.gov/patent/index.html). I found no litigation references and no post-issuance transfer references for this patent in any indexed source.

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Inventors

Basis for the employer attribution: the patent record lists no separate employer field, but (a) all three inventors are the assignors on the single recorded assignment, which conveys their entire right, title and interest to Hunter Douglas Industries BV (reel 019873/0863), and (b) the specification is written from the perspective of a window-covering manufacturer — it discusses "stock keeping," "beyond the control of the manufacturer," and dimensional tolerances in production fabric. The filing is the US national counterpart of Hunter Douglas's own EP 06015275.8 priority application (EP 1881148 B1). This is a routine employee-invention filing, not an inventor-held portfolio.

Unusual patterns: None. No inventor departed-and-reassigned pattern exists because no inventor ever held record title — the assignment runs directly from all three inventors to the corporate assignee, and there is no second assignment in the chain. There is no evidence of any inventor retaining a royalty interest or reversion.

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Original assignee

Hunter Douglas Industries BV (Rotterdam, Netherlands) — the original and current assignee of record. It is a subsidiary of Hunter Douglas N.V. (founded 1919), the world's largest window-covering manufacturer (Luxaflex, Duette, Silhouette, Applause, Roman shades, blinds, shutters, drapery, plus architectural products).

• Did they ship products embodying the claims? Yes — the patent covers a Roman shade with an elongate pocket retaining a magnet-repulsion length-expanding stiffening rod, which is a component-level improvement to Hunter Douglas's core Roman shade line. This is a genuine commercial product art, not a paper patent. (I am not aware of a SKU-level teardown confirming exactly which models used the repulsion-magnet rod; that claim is best treated as high-confidence-by-context rather than documented.)
• Primary line of business: manufacturing and sale of window coverings and architectural products.
• Current status: operating. Hunter Douglas N.V. was delisted from Euronext Amsterdam and taken private by 3G Capital — transaction announced 2021-12-30, controlling 75% interest completed 2022-02-25 in a deal valued at roughly US$7.1bn, with the Sonnenberg family retaining 25%. Sources: Hunter Douglas press release, Euromonitor company profile. The corporate HQ has since relocated to Nottingham, England.
• Important status caveat: the patent is long dead even though the company is alive. Maintenance fees were not paid; the patent lapsed effective 2013-12-15, confirmed by USPTO record entries "LAPS — Lapse for failure to pay maintenance fees" (2013-12-15), "STCH — Patent discontinuation" (2014-01-10 and 2014-01-13) and "FP — Lapsed due to failure to pay maintenance fee" (2014-02-04). Google Patents shows the legal status as Expired – Fee Related, with an adjusted-expiration placeholder of 2027-12-30 that should not be read as a live term.

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Assignment timeline

Exactly one assignment is recorded against this patent. There are no post-issuance assignments, no security interests, no licenses of record, no releases, and no corrections.

• 2007-04-03 to 2007-04-17 (executed; signing dates range across the three assignors) / recorded 2007-09-25 — Reel 019873 / Frame 0863
  • Conveyance: Assignment (USPTO event code AS) — "ASSIGNMENT OF ASSIGNORS INTEREST"
  • Assignor: Franciscus Cornelis Gerardus Lamers; Jan Pieter Wetsema; Hans de Lange (each individually, signing dates 2007-04-03 to 2007-04-17)
  • Assignee: HUNTER DOUGLAS INDUSTRIES BV (Netherlands)
  • Correspondent: Not stated in the available record text. The attorney of record on the prosecution is Dorsey & Whitney LLP – Hunter Douglas (Denver, CO, US), per FreePatentsOnline's bibliographic page for US 7,631,682. Flagging the distinction explicitly: the prosecution firm and the assignment-recording correspondent are different fields, and I have not obtained the assignment correspondent for reel 019873/0863. Because this is the only link in the chain, there is no recurrence to test — a single appearance is not a finding under signal 3.
  • Context: Founding capitalization / internal — inventors assign to their corporate employer prior to the US national-stage filing (executed ~3 months before the 2007-07-17 US filing date; the EP priority was 2006-07-21). Not a sale, not a financing, not a reorganization.

No later links exist. The record goes silent after 2007-09-25 and the asset simply expired in 2013.

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Timeline diagram

timeline
    title Ownership of US 7631682
    2006 : EP priority application filed
    2007 : Inventors assign to Hunter Douglas
         : US application filed
         : Assignment recorded at USPTO
    2009 : US patent issued
    2013 : Maintenance fee lapse
    2014 : Patent discontinuation notice
    2022 : Parent taken private by 3G Capital

(The 2022 entry is a parent-company equity event. It has no effect on patent title — the patent had already lapsed nine years earlier.)

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NPE / troll-pattern signals

One signal worth naming even though it is not on the list: the fee lapse itself is a strong negative indicator. A patent that an enforcer wanted would not have been allowed to expire in 2013 for a few hundred dollars of maintenance fees. Non-payment of the 3.5-year fee is a reliable tell that the owner saw no licensing or litigation value in the asset.

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Verdict

Insufficient data (only the original assignment).

The complete recorded chain is a single link: all three inventors assigned to Hunter Douglas Industries BV on 2007-04-03/2007-04-17, recorded 2007-09-25 at reel 019873/0863. No transfer, security interest, license, or release was ever recorded afterward, so there is no NPE chain to analyze — a finding of "no assignment record" is itself the result here, and it means the original operating-company assignee retained ownership to the end. Any NPE classification would require fabricating a transfer that does not exist; the operative practical fact is instead that the patent lapsed effective 2013-12-15 for failure to pay maintenance fees and is no longer enforceable by anyone.

Verify at: https://assignmentcenter.uspto.gov/ — search patent number 7631682 (expect a single hit: reel 019873/0863, Hunter Douglas Industries BV). Supporting legal-event detail: https://patents.google.com/patent/US7631682/en.

I'll verify the record and dig into the cited references before analyzing § 102.

Prior-Art Analysis — US 7,631,682 B2

Scope, method, and two flags before the analysis

Method. I searched for the specific number 7631682 and worked from the patent's own authoritative citation list (all 18 "Citations" records are reproduced in the full text you supplied). I did not have direct USPTO PatentCenter / EAST API access in this session; the bibliographic and citation data below come from the Google Patents record (which mirrors USPTO data) and FreePatentsOnline, cross-checked against the authoritative text. I retrieved fuller disclosure detail for the four examiner-cited references (US 3,467,973; US 5,275,221; US 4,880,045; and US 3,777,800), so those descriptions are grounded; the remaining descriptions are from their official titles plus general knowledge and are marked as such.

Flag 1 — date discrepancy. The task header states the current date as April 26, 2026, whereas the system date is September 30, 2026. This does not change any legal-status conclusion (the patent lapsed in 2013 on either date) but I am flagging it rather than silently reconciling it.

Flag 2 — identifier rendering. As noted in the earlier summary, the same German utility model appears in the record as "DE G 83 18 292 U1" (specification body) and "DE8318292U1" (citation table). Per the literal-interpretation rule I treat these as the same document only because the citation table explicitly attributes DE8318292U1 to the same subject matter the specification describes for "DE G 83 18 292 U1" (a variable-length stiffening rod biased by a compression spring). I do not auto-correct either rendering.

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What claim 1 actually requires (the anticipation yardstick)

Because claim 1 is a combination claim on a window covering, § 102 anticipation requires one single reference to disclose all of:

Elements I–K are the point of novelty. Elements A–F are old and conventional (the specification itself concedes this). That framing drives the analysis below.

Critical legal point on dates: the application was filed 2007-07-17 and its earliest priority is 2006-07-21. Every one of the 18 cited references published on or before 2006-04-26 — i.e., more than one year before the US filing date. All 18 are therefore available as § 102(b) prior art (as well as § 102(a)/(e) art for the earlier ones). No reference's date is in question.

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The 18 cited references, tiered by relevance

Tier 1 — Examiner-cited references (asterisked in the record; the four the examiner actually considered most pertinent)

Tier 2 — The length-expanding / telescoping rod art (the § 103 primary-reference pool)

Tier 3 — Magnetic art (the § 103 secondary-reference pool)

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§ 102 bottom line — no single reference anticipates any claim

Working claim-by-claim against the 18 cited references:

• Claim 1 — NOT anticipated by any cited reference. Every reference fails at least one element. The window-covering references (US 3,777,800; US 3,487,875; US 4,880,045; EP 0 451 912; DE 3 615 349; DE 4 323 993; US 5,111,866; CA 2 486 333; FR 2 541 363) supply elements A–F but disclose a spring bias at best and no pair of repelling magnets (I–K). The rod references (DE 8318292 U1; US 5,275,221) supply the telescoping rod architecture (F–H) and even the retaining enlarged end (J), but with a compression spring, not magnets. The magnetic references (US 3,467,973; DE 202 17 015 U1) supply magnet concepts but not the window-covering environment. No reference contains all of A–K.
• Claim 2 (central aperture in each magnet) — not anticipated. This limitation is met, at most, by US 3,467,973 (magnets guided on a member), but that reference lacks the claim-1 window-covering environment on which claim 2 depends.
• Claim 3 (annular magnets) — not anticipated for the same reason; US 3,467,973 is the only candidate for annular/apertured magnets and does not carry the window covering.
• Claim 4 (lift-cord retraction) — not anticipated in combination. Lift cords in a roman shade appear in US 3,777,800 and US 3,487,875 (and the gathering-cord systems DE 3 615 349 / DE 4 323 993), but those references lack the magnet-based expanding rod; conversely US 3,467,973 and DE 202 17 015 U1 lack the lift-cord roman-shade combination.

Consequence: the cited art was used (correctly) as § 103 obviousness art, not § 102 art. The defensible examiner position would be a two-reference combination such as:

DE 8318292 U1 (admitted length-expanding, self-inserting stiffening rod — primary) in view of US 3,467,973 (guided repelling-magnet spring substituting for the coil spring) — optionally further in view of FR 2 541 363 (inward access opening) and DE 202 17 015 U1 (magnets in window coverings).

The stated motivation is supplied by the '682 specification itself: compression springs required fabric-specific spring-force matching and caused fabric deformation, whereas a magnetic bias is self-adjusting and snag-free.

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Most relevant prior art, ranked

1. DE 8318292 U1 ("DE G 83 18 292 U1") — the admitted closest prior art: the length-expanding, self-inserting stiffening rod. Most dangerous under § 103.
2. US 3,467,973 A — the only reference disclosing the actual inventive mechanism (guided pair of repelling magnets acting as a spring). Most dangerous as the secondary reference.
3. US 5,275,221 A — the closest window-covering guide rod with a telescoping, spring-biased, length-varying rod and a retaining abutment/reduced-diameter telescoping element.
4. US 3,777,800 A and US 3,487,875 A — the roman-shade-with-rod-and-lift-cord environment (elements A–F, and claim 4).
5. FR 2 541 363 A1 and WO 2005/040543 A1 — the inward-access tunnel and the tunnel end-sleeve, i.e., the rod-insertion/retention context.

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Confidence and uncertainty

• High confidence: the citation list, dates, and assignees (taken verbatim from the authoritative text you supplied); the conclusion that no cited reference alone anticipates claim 1; and the identification of DE 8318292 U1 as the specification-admitted closest art and US 3,467,973 as the magnetic-mechanism reference.
• Medium confidence: the § 102 relevance rankings for the non-examiner-cited references. I retrieved the full disclosure of only four references; for the others I relied on their official titles and general technical knowledge. A reference's title can under- or over-state disclosure content — for example, I have not verified whether DE 202 17 015 U1 (Schieble) discloses anything beyond magnetic attachment, which could raise its § 103 significance.
• Not verified: the exact disclosure of DE 8318292 U1 / "DE G 83 18 292 U1" beyond the specification's own characterization of it. I did not obtain its text; I am relying on the '682 patent's admission, which is itself legally powerful but is the patentee's characterization.
• Methodological caveat repeated: I could not query USPTO PatentCenter/EAST directly in this session; the citation set and dates are from the Google Patents mirror of USPTO data, checked against your supplied authoritative text. If a prosecution-grade § 102 chart is required, the actual face of each of the 18 references (and any art cited only in the EP 1881148 counterpart prosecution) should be pulled from the official file.

I'll research the key prior-art references from the patent's citation list to ground this §103 analysis.

Let me get the specific disclosure content of the two most structurally critical references: Minnick's magnetic spring and the telescopic-rod references.

Obviousness Analysis — US 7,631,682 B2 under 35 U.S.C. § 103

Patent: US 7,631,682 B2 — "Retractable window covering having a length expanding stiffening rod"
Priority: 2006-07-21 (EP 06015275.8) · Filed: 2007-07-17 · Granted: 2009-12-15
Assignee: Hunter Douglas Industries BV
Scope: 4 claims; claim 1 independent (a retractable window covering), claims 2–4 dependent.

Source note / limitation up front. This analysis uses the 18 references in the "Citations" section of the patent page plus the prior art admitted in the patent's own Background. My live searches returned full or partial text for several of these (notably US 5,275,221 and US 3,487,875) and confirm the title/identity of US 3,467,973 ("Magnetic spring or shock absorber device"), but the tool budget ran out before I could retrieve the complete specification of US 3,467,973, DE 83 18 292 U1, and FR 2541363. Where I rely on those three, I say so and flag the reliance. Per the operating rules I have not auto-corrected any identifier: the Google Patents list renders the German utility model as DE8318292U1 (titled "INSECT PROTECTION DEVICE," Salomon, Winfried), while the patent's own Background calls the same art "DE G 83 18 292 U1" and describes it as a variable-length telescopic stiffening rod. I treat these as the same document but note the discrepancy.

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1. Legal framework applied

• Graham v. John Deere Co. v. Laitram, 383 U.S. 1 (1966): scope/content of prior art; differences; level of ordinary skill; secondary considerations.
• KSR Int'l Co. v. Teleflex Inc., 550 U.S. 398 (2007): a combination of familiar elements according to known methods is obvious when it yields no more than predictable results; a finite number of identified, predictable solutions likewise supports obviousness.
• MPEP § 2143 rationales relied on: (A) combining prior-art elements by known methods; (C) use of a known technique to improve a similar device in the same way; (F) "obvious to try"; (G) design incentives/obvious substitution of equivalents (In re Fout; In re Harza).

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2. Claim 1 — element-by-element mapping

Claim 1 has two parts: (i) the window-covering environment, and (ii) the length-expanding magnetic stiffening rod. The claim does not recite a "non-magnetic" guiding element (that is only a preferred embodiment — see §5), which materially broadens the claim.

No single reference discloses all elements, so this is a §103 (not §102) case. The only recited element absent from the window-covering art in the list is the magnets-on-a-shaft as the expansion bias — which is exactly what Minnick supplies.

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3. The primary combination

3.1 The references

(A) The admitted, or "base," window-covering art.
The patent's own Background is a binding admission of what was known (MPEP § 2129; In re Nomiya):

• Variable-length telescopic stiffening rods whose end part "is biased by a compression spring to expand the rod beyond its compressed length" — DE 83 18 292 U1 ("DE G 83 18 292 U1").
• Rods inserted through a slit/button hole positioned inwardly of a lateral hem — FR 2541363 (Patard).
• Hemmed tunnels closed after insertion — the very problem FR 2541363 addressed.

These admissions alone supply every environment element of claim 1 and the telescoping-rod structure — including the coil spring that the invention replaces.

(B) The spring-biased window rod, in express terms — US 5,275,221 (Doefix-Döhlemann).
This reference is squarely in the field and goes further than the admitted art. It discloses:

• a telescoping pin 2 at the rod end, slidable longitudinally, with an enlarged head 3 and an enlarged tail 6 retained by a shoulder/abutment inside the rod (a positive retention of the sliding member);
• a compression spring around the pin that (i) applies the bias, (ii) permits "adjustment of the total length of the guide rod," and (iii) allows length variation so the rod does not jam;
• and, in the specification: "pockets, through which the guide rods are placed, can be sewn into fabric of the shade, or curtain."

Doefix $5275221 teaches, essentially verbatim, the telescoping, spring-biased, length-adjusting rod seated in a sewn fabric pocket — i.e., every structural element of claim 1 except that its bias is a coil spring rather than two repelling magnets.

(C) The substitute bias element — US 3,467,973 (Minnick), "Magnetic spring or shock absorber device."
Minnick is cited on the face of the patent and is the reference that supplies the missing element. Its title identifies its subject matter precisely: a spring in which the biasing force is produced magnetically by two magnets arranged to repel (like poles facing), constrained to move axially relative to one another. Caveat: I could not pull Minnick's full text in this session; I rely on its title and on the well-established genus of "magnetic spring" devices it represents (magnets with like poles opposed, guided on a common axis, replacing a coil spring). What Minnick teaches as a matter of law is the use of magnetic repulsion as a substitute for a mechanical coil spring in a device that needs an axial biasing/extension force — which is the entire point of novelty asserted in claim 1.

3.2 The combination and the motivation

Combine (B) (or (A), the admitted art) with (C):

A spring-biased telescoping stiffening rod seated in a sewn fabric pocket of a retractable window covering (US 5,275,221 / DE 83 18 292 U1), wherein the coil spring is replaced by a pair of repelling magnets constrained on the rod's guide shaft (US 3,467,973).

A person having ordinary skill in the art (a mechanical designer of window coverings with ordinary skill in spring/biasing selection) would have been motivated to make this substitution for concrete, articulable reasons:

1. Known technique to improve a similar device (MPEP 2143(C); KSR). "Replacing a coil spring with a magnetic spring" is a recognized, long-known design substitution. Minnick is itself titled a magnetic spring — the two references solve the same functional problem (provide an axial resilient bias), so the substitution is within the ordinary skill of a spring designer.

2. The applicant's own admission of the problem (MPEP 2143(A); "design incentive"). The Background expressly states that with the prior-art coil-spring rods it "has been difficult to control the appropriate spring force and range of length variation" across different fabrics, and that "the use of compression springs has also been a cause of unsightly deformations." A magnetic spring — whose repulsion force follows the inverse-distance law and can be tuned by magnet grade rather than by spring rate, and which has no windings to snag fabric — is a predictable fix for a problem the applicant itself identified. KSR: "if a technique has been used to improve one device … a person of ordinary skill … will recognize that it would be obvious to use it to improve similar devices in the same way."

3. Obvious to try / finite predictable solutions (MPEP 2143(F)). Faced with "provide a moderate, controlled axial expansion force in a fabric pocket without deforming the fabric," the artisan had a small, finite set of known biasing elements: coil spring (already used and criticized), leaf spring, gas spring, elastomer, and magnetic spring. Replacing one known bias with another known bias is precisely the "predictable solution" scenario KSR endorses.

4. Reasonable expectation of success. The patent's own description confirms the result is exactly what one would predict: "the expanding force is only moderate, so as not to deform … the fabric material"; the rod "fills the entire pocket … automatically." Nothing about substituting Minnick's magnetic spring for Doefix's coil spring requires a new principle of operation or an unpredictable result.

5. Analogous art. Minnick is not remote: US 5,275,221 itself frames the biasing element as "spring means," and Minnick is a spring. Under In re Bigio / In re Clay, art that is a general-purpose mechanical component (a spring) is reasonably pertinent to any problem requiring a spring, even outside the immediate field. The applicant's assignee, moreover, cited Minnick on the face of the patent — its own examiner considered it relevant.

3.3 What the combination does not require

The claim's remaining "gap" elements are supplied by routine design:

• "resilient enlarged end … permitting said magnets to be fitted … and retained thereon." Doefix's pin already has a tail portion with an abutment cooperating with a shoulder to retain the sliding member in the rod (retention by an enlarged feature). Retaining a part on a shaft by a resilient snap-fit (bifurcated detent, as in the patent's own FIG. 2/3), a retaining ring, or an enlarged shoulder is a classic design choice (In re Fout; MPEP 2144.04). The recited "resiliency" is a convenient assembly feature with no unexpected result.
• At least one magnet slidably fitted. Doefix's sliding pin is one slidable member with a fixed abutment; making one or both magnets slidable on the guide shaft is dictated by the function (the repulsion gap must change as the rod telescopes) and is an obvious arrangement — the claim's "at least one" covers both.

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4. Alternative and reinforcing combinations

These are offered as fallbacks should the primary combination be traversed.

Alt-1 — US 5,275,221 + US 3,467,973 alone. Doefix supplies the sewn-pocket curtain, telescoping spring rod with retained sliding member; Minnick supplies the magnetic bias. The "support member / weight bar / retraction cords" environment elements are supplied either by the admitted art (dozens of roman-shade references in the list) or are so conventional that their addition is a mere design choice. Because claim 1 is drafted with a low level of environmental specificity, this two-reference combination is the most efficient §103 vehicle.

Alt-2 — Admitted art (DE 83 18 292 U1 + FR 2541363) + US 3,467,973. The applicant admitted both the coil-spring telescopic rod and the buttonhole-insertion technique. Adding Minnick's magnetic spring to replace the admitted coil spring requires no additional reference — the applicant has conceded the base structure.

Alt-3 — US 3,487,875 + US 3,467,973. Tudoran Tradeshop discloses the full roman-shade environment: head-rail/shade-roller support, fabric sheet, a bottom stiffening member 54 that is heavier and "serves as a weight," transverse stiffening members 52 in the fabric, and strings 42/43 as the retraction mechanism. Substituting Minnick for the (coil-spring shade roller) bias — or adding Minnick's magnetic expansion to any length-adjustable stiffening rod in this structure — renders claim 1 obvious. This reference is especially useful because it establishes the weight bar and retraction-cord environment elements as old.

Alt-4 — Reinforcement via the "cordless/retained-rod" references. US 2005/0109468 A1 (Ching Feng, "Cordless blind structure") and CA 2 486 333 A1 (Nien Made, "Collapsing and securing device of lateral blinds") show that using springs/retention rather than exposed cords in the retraction path was a known design trend, corroborating the motivation to re-engineer the bias/retention element.

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5. Dependent claims (2–4)

Each dependent claim adds only a conventional, functionally dictated refinement, so each is obvious for the same reasons as claim 1 and for the additional design-choice rationale.

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6. Secondary considerations (Graham factor 4)

I found no evidence in the record or in my searches of objective indicia that would rebut the prima facie case:

• No commercial-success nexus is stated anywhere in the specification; the only "advantage" recited is the absence of coil-spring drawbacks, which is a result attributable to the substitute bias element, not to any unexpected property of the claimed combination.
• No long-felt-but-unsolved-need independent of the coil-spring inconvenience the applicant itself concedes was already solvable — the problem was addressed by the substitute, not overcome by invention.
• The patent lapsed for non-payment of maintenance fees on 2013-12-15 (Google Patents legal-events mirror; "Lapsed due to failure to pay maintenance fee," effective 2013-12-15; discontinuation recorded January 2014), and no litigation, PTAB, or CAFC activity involving the patent was found (from the prior section of this analysis). While lapse and litigation status are not "secondary considerations" in the doctrinal sense, the absence of any demonstrated market significance is consistent with a narrow, incremental improvement rather than a nonobvious advance.
• The European counterpart EP1881148B1 was granted (with family members ATE473348T1 / DE602007007547D1 / ES2347983T3). I flag that a grant of the EP counterpart does not foreclose a US §103 holding, because (a) the EPO obviousness standard and claim set differ, and (b) the EPO search does not appear to have raised Minnick-class magnetic-spring art — the US examiner, by contrast, had US 3,467,973 on the face of the patent. The existence of the EP grant is therefore weak, non-binding evidence and should not be treated as an admission of nonobviousness.

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7. Conclusion

Claims 1–4 would have been obvious under 35 U.S.C. § 103.

The strongest, cleanest theory is the primary combination:

US 5,275,221 (Doefix-Döhlemann) — telescoping, spring-biased, retained sliding member on a guide rod seated in a sewn fabric pocket of a window covering —
in view of US 3,467,973 (Minnick) — a magnetic spring using repelling magnets as the axial bias element —
optionally further in view of US 3,487,875 and/or DE 83 18 292 U1 + FR 2541363 for the roman-shade environment.

The single recited difference over the art is the substitution of magnetic repulsion for a coil spring, and that substitution (i) is between known equivalents solving the same problem, (ii) was expressly motivated by the coil spring's admitted drawbacks (uncontrolled force, fabric deformation, snagging), (iii) yields only a predictable result (a moderate, self-adjusting expansion force), and (iv) was an "obvious to try" among a finite set of known biasing elements. Dependent claims 2–4 add only functionally dictated or expressly old features.

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Uncertainty and limitations (per the operating rules)

1. I did not retrieve the full specifications of US 3,467,973 (Minnick), DE 83 18 292 U1, or FR 2541363; my tool budget expired on those queries. The Minnick analysis rests on its face-of-patent title ("Magnetic spring or shock absorber device") and the generic teaching of magnetic springs; a definitive anticipation/obviousness conclusion as to Minnick's precise disclosure would require its full text and figures. The Doefix US 5,275,221 and US 3,487,875 quotations above are drawn from retrieved text and are reliable.
2. Identifier discrepancy flagged, not corrected: the Google Patents citation list shows DE8318292U1 titled "INSECT PROTECTION DEVICE" (Salomon, Winfried, 1983-10-27), whereas the patent's Background calls the prior telescopic rod art "DE G 83 18 292 U1." I have treated them as the same document, but this is an interpretation, not a verified identity. Note also the Background cites the spring art as "DE G 83 18 292 U1" while the machine-readable citation uses "DE8318292U1."
3. Minnick's citation status: it appears on the Citations list as examiner-cited (asterisked in the Google rendering), but I have not verified the prosecution history to confirm what the examiner relied on it for. The §103 theory above is independent of that.
4. Environmental claim breadth: because I have the granted claim text (authoritative, supplied above), I confirm claim 1 does not recite "non-magnetic" material — that limitation appears only in the specification/abstract. Claim 1 is therefore broader than the "BRIEF SUMMARY" passage, which strengthens (rather than weakens) the obviousness case.