US 11435542

I'll search authoritative sources for this specific patent and its current litigation/PTAB status.

US Patent 11,435,542 — Analyst Summary

Search scope note: I searched for the literal identifier 11435542 / 11,435,542. Be aware that live results also surface unrelated patents sharing the "542" suffix — e.g., a Genzyme rAAV formulation patent that "issued on June 9, 2015" and was IPR'd by Sarepta. Those hits are not this patent and I have excluded them. Everything below is tied to application 17/010,113 / patent 11,435,542 B2.

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1. Bibliographic data

Sources: https://patents.google.com/patent/US11435542/en ; prosecution papers at https://ptacts.uspto.gov/ptacts/public-informations/petitions/[1556427](/patent/1556427)/

Lineage: it is a continuation of US 16/143,831 (issued as US 10,795,107 B2), which claims §119(e) benefit of provisional 62/567,339. It has its own continuations: US 17/929,566 (→ US 11,656,422), US 18/105,639 (→ US 11,740,423), US 18/328,431 (→ US 12,313,896), US 18/232,729 (→ US 12,332,491), and US 19/239,502 (→ US 2025/0306324 A1, pending).

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2. Abstract (as issued)

A fiber optic cassette system is disclosed comprising a case defining a tray receiving space and an opening to a space, a tray received within the case for movement between a stored position wherein the tray is inside the case and an accessible position wherein a front end of the tray is in front of the opening and outside of the case, fiber optic cassettes arrangeable side by side along the tray front end, a first of the cassettes comprising a width of one of one, two, three, four or six standard width units and a second of the cassettes comprising a width different from the first cassette width and one of one, two, three, four or six standard width units, and a fastener for removeably the cassettes to the tray. When arranged on the tray each of said selected cassettes is directly adjacent at least one other selected cassette.

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3. Plain-language overview of the independent claims

Claim 1 — the system claim

A rack-mountable fiber-optic enclosure system with:

• a case made of top and bottom walls plus two side walls, defining an internal tray-receiving space with a front opening;
• at least one sliding tray that moves between stored (fully inside the case) and accessible (front end pulled out past the opening) positions;
• a set of cassettes that can be arranged side by side along the tray's front end, each cassette having a row of optical plug receptacles on its front face;
• the key point: a first cassette has a width (measured between its outer side edges) of 1, 2, 3, 4 or 6 "standard width units," and a second cassette has a different width that is also one of 1, 2, 3, 4, or 6 standard width units — i.e., mixed-width cassettes coexist on one tray; and
• a fastener that releasably secures each cassette to the tray.
• Final limitation: when installed, each selected cassette's outer side edge is directly adjacent another selected cassette's outer side edge (no spacer rails between cassettes).

Claim 8 — the method claim

A method of organizing a fiber-optic tray that has a front edge:

1. Define a standard width unit such that the front edge width is substantially evenly divisible by it;
2. Select cassettes to install from a set whose widths are each evenly divisible by that unit;
3. Releasably secure the selected cassettes along the tray's front edge;
4. Again, the installed cassettes must be edge-to-edge directly adjacent one another.

Dependent-claim context (for completeness): claim 2 (tray ≥12 width units), claim 3 (rear multi-fiber connector receptacle + interconnecting fibers), claim 4 (four receptacles per standard width unit), claim 5 (pair of rack mounting brackets), claim 6 (ferrous tray + magnet fastener), claim 7 (elongate cable-management bracket of one width unit with a loop positioned in front of and beside an installed cassette's receptacles); claims 9–13 recite the 1/2/3/4/6 sizes, same-width sets, mixed-width sets, a third differing width, and a maximum of twelve width units across the front edge.

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4. Post-grant status — materially changed (important)

This is not a cleanly-enforced patent today:

• IPR2024-01227, CommScope Technologies LLC v. Belden Canada ULC, filed July 26, 2024, challenging claims 1–5 and 8–13; instituted Feb 27, 2025; terminated Sept 8, 2025 with adverse judgment entered against the challenged claims.
  • https://ipverse.greyb.com/ptab-web/cases/case-details/IPR2024-01227
• Belden filed a statutory disclaimer of claims 1–5 and 8–13 (effective July 17, 2025, recorded Aug 2025). See Exhibit 2005 in Belden's Motion to Withdraw its Motion to Amend ("Patent Owner statutorily disclaimed all Challenged Claims under 35 U.S.C. § 253(a) and 37 C.F.R. § 1.321(a)"). https://ptacts.uspto.gov/ptacts/public-informations/petitions/[1556426](/patent/1556426)/
• An IPR certificate (K1) issued Dec 15, 2025 (published Dec 23, 2025) — per Google Patents' legal-events table.
• Net effect: on the face of the record, only claims 6 and 7 remain in force, and both depend from the now-disclaimed claim 1. I flag the consequence as my own reading rather than an authoritative holding: dependent claims 6/7 are not themselves disclaimed, but their scope incorporates claim 1's limitations.
• This was part of a coordinated four-IPR campaign: IPR2024-01218 ('107), -01227 ('542), -01228 ('422), -01382 ('423). Belden disclaimed the challenged claims, withdrew its motions to amend, and pivoted to two newly issued family members, US 12,313,896 B2 and US 12,332,491 B2, which became the basis of a second infringement suit against CommScope.
• Maintenance fee: 4th year paid March 6, 2026 (large entity).

Litigation

• Belden Canada ULC v. CommScope, Inc. et al., 1:23-cv-00810-RGA (D. Del.) — asserted the '542 patent along with US 10,795,107, 11,656,422 and 11,740,423; stayed Sept 4, 2024 pending the IPRs, then administratively closed.
• CAFC 2026 dockets: the only 2026 Federal Circuit matter between these parties that I found is 2026-1255 / 2026-1285, Belden Canada ULC v. CommScope, Inc., dismissed by joint stipulation on June 29, 2026 (Fed. R. App. P. 42(b)). Importantly, that appeal arises from D. Del. No. 1:22-cv-00782-RGA, which asserted US 6,409,547 B1 — not the '542 patent.
  • https://cafc.uscourts.gov/opinions-orders/26-1255.ORDER.6-29-2026_2716159.pdf
  • https://law.justia.com/cases/federal/appellate-courts/cafc/26-1255/26-1255-2026-06-29.html
• I also found 2025-1428, CommScope Technologies LLC v. Belden Inc. (appeal from IPR2023-01056), dismissed June 26, 2026 — again not this patent.

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5. Uncertainty / caveats

• I did not directly retrieve the USPTO Patent Center or Assignment records; bibliographic and legal-events data come from the Google Patents full-text record plus PTAB filings. Treat the disclaimer date (July 17, 2025) and IPR certificate date (Dec 15, 2025) as reportable but unverified against the official USPTO register.
• The exact surviving-claim analysis (claims 6 and 7 living on after claim 1's disclaimer) is my interpretation of standard §253 practice; I have not found an authoritative USPTO or court statement on the point for this patent.
• The Delaware docket 1:23-cv-00810 was stayed/administratively closed, so a reinstated action remains conceivable; I found no 2026 order reopening it.
• I found no Federal Circuit 2026 docket that specifically names US 11,435,542. Any "CAFC 2026" hit tying Belden to CommScope relates to different patents.

I'll research litigation involving US patent 11435542 using the sources you specified.

Let me dig deeper into the specific case details and check for any other proceedings.

Litigation Involving U.S. Patent No. 11,435,542

Short answer: The '542 patent ("Modular fiber optic cassette, system and method," issued Sept. 6, 2022, Belden Canada ULC) was asserted in one known U.S. district court action — Belden Canada ULC v. CommScope, Inc. et al., No. 1:23‑cv‑00810‑RGA (D. Del.) — which was stayed and administratively closed pending one known PTAB inter partes review, IPR2024‑01227, which terminated in adverse judgment against Belden on Sept. 8, 2025, followed by a statutory disclaimer of claims 1‑5 and 8‑13 and issuance of the IPR certificate. I found no other district court, ITC, or appellate case that specifically names the '542 patent, and I found no confirmed Canadian or foreign litigation naming it.

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1. District court litigation

Counsel of record (for completeness): Plaintiff — Robert M. Vrana, Pilar G. Kraman (Young Conaway Stargatt & Taylor); Douglas J. Nash, John D. Cook, Naresh K. Kannan, Genevieve M. Halpenny (Barclay Damon / pro hac vice). Defendants — Kelly E. Farnan, Sara M. Metzler (Richards, Layton & Finger); Philip P. Caspers, Dennis C. Bremer, Tara C. Norgard, Timothy A. Lindquist, Joseph W. Winkels and others (Carlson, Caspers).

Sources: Justia Dockets (https://dockets.justia.com/docket/delaware/dedce/1:2023cv00810/83154); Joint Claim Construction Chart filed in C.A. No. 23‑810‑RGA (available at https://www.docketalarm.com/cases/PTAB/IPR2024-01382/CommScope_Technologies_LLC/docs/08-30-2024-Petitioner/Exhibit-1011-Joint_Claim_Construction_Chart_from_co_pending_litigation_.pdf); Google Patents litigation entry linking case 1:23‑cv‑00810 (https://patents.google.com/patent/US11435542/en); PatSnap case analysis (https://www.patsnap.com/de/resources/blog/litigation/belden-canada-v-commscope-fiber-optic-patent-infringement-patsnap/).

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2. PTAB proceeding directly on the '542 patent (the operative challenge)

Related IPRs on sibling patents, all filed July 26, 2024, all terminated with adverse judgment: IPR2024‑01218 (US 10,795,107), IPR2024‑01228 (US 11,656,422), IPR2024‑01382 (US 11,740,423).

Statutory disclaimer of '542 claims: The Google Patents record for US 11,435,542 shows a disclaimer filed Aug. 26, 2025 (effective July 17, 2025) disclaiming complete claims 1‑5 and 8‑13. Note that claims 6 and 7 are not in that disclaimer, and the patent's status is still shown as Active (4th‑year maintenance fee paid March 6, 2026; anticipated expiration 2038‑09‑27). I have not verified independently which claims were challenged in the petition, and I recommend confirming against the IPR2024‑01227 petition and the certificate if the exact surviving claim set matters to you.

Sources: GreyB IPVerse case page (https://ipverse.greyb.com/ptab-web/cases/case-details/IPR2024-01227); PTAB Order authorizing withdrawal of motions to amend and termination with adverse judgment (https://ptacts.uspto.gov/ptacts/public-informations/petitions/[1556612](/patent/1556612)/download-documents?artifactId=aIE8uPDCizdHebQ0CDVrB6vvHUIhV1nsH2gk3phaJ1B7AmeD2kv7u2s); Board/party correspondence filed Aug. 4, 2025 (https://www.docketalarm.com/cases/PTAB/IPR2024-01228/CommScope_Technologies_LLC_v._Belden_Canada_ULC/08-04-2025-Board/Exhibit-3002-Ex_3001_Attorney_Correspondence_2/); Google Patents legal events for US11435542B2.

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3. Other potentially related proceedings (not confirmed as involving the '542 patent)

• Second Delaware suit, 2025: A Belden Canada ULC v. CommScope, LLC et al. action, No. 1:2025‑cv‑00870 (D. Del.), appears on Justia's CommScope docket list. The PTAB record describes it as a "second patent infringement lawsuit … based on those two new patents" issued in the same family (i.e., the newer continuation patents, not the '542). I could not confirm that the '542 patent is asserted in 1:25‑cv‑00870 — treat this as unverified.
• Federal Circuit appeals by Belden Inc.: Belden Inc. v. CommScope Technologies LLC, Nos. 25‑1428, 25‑1440, 25‑1441 (Fed. Cir.), appear in Justia's CommScope appellant/appellee listing. These are likely appeals from the related IPR outcomes, but I could not verify that any of them arises from IPR2024‑01227 / the '542 patent. Because IPR2024‑01227 ended in adverse judgment rather than a final written decision, it is not the natural candidate for appeal.
• Unrelated Belden–CommScope '547 patent case: Note that Belden Canada ULC v. CommScope, Inc., No. 1:22‑cv‑00782‑RGA (D. Del.), concerning US 6,409,547 B1 and disposed of by a stipulated judgment in October 2025, is a different case and a different patent — PatSnap's "Delaware District Court" page conflates the two, so do not attribute its outcome to the '542 patent.
• Canadian / foreign litigation: The Google Patents page carries a Darts‑IP "First worldwide family litigation filed" flag for family ID 65896043, which is family‑level, not patent‑specific. I found no confirmed Canadian (e.g., Federal Court) or other foreign action naming the '542 patent. Searches of Unified Patents' litigation portal returned only the U.S. District of Delaware case.
• Also noted in the file: CommScope Technologies LLC v. Belden, Inc., IPR2023‑01062 (PTAB, filed June 13, 2023) — this concerns a different patent (apparently US 6,570,095) and is not a '542 proceeding.

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4. Bottom line

Caveats: (a) I did not independently pull the PACER docket or the PTAB petition/certificate in full; the case details above are drawn from public aggregators (Justia, Docket Alarm, GreyB, PatSnap, Google Patents) and the parties' own PTAB filings reproduced there. (b) The exact claim set challenged in IPR2024‑01227 and the precise reason for the adverse judgment should be confirmed against the certificate if it is material. (c) It is possible that additional actions exist that are not indexed under the patent number itself (e.g., actions where the '542 patent is named only in an exhibit or where the case is confidential); my searches did not surface any.

I'll research the IPR identified in the patent record and any related PTAB/Federal Circuit activity.

Let me dig into the specific IPR's claim challenges, panel, institution reasoning, and any appeal.

Let me pull the institution decision and adverse judgment specifics, and check for any appeal.

PTAB / AIA Trial Activity — US 11,435,542 ("Modular fiber optic cassette, system and method")

Discrepancy flag — read first. The structured "PTAB proceedings on file" block provided in this prompt states that the USPTO ODP API returns no AIA trial proceedings for this patent. That is wrong, or at least badly stale. The patent's own record (Google Patents legal events and family/litigation block) and multiple independent sources confirm IPR2024-01227, instituted 2025-02-27, terminated by adverse judgment 2025-09-08, with an IPR certificate issued 2025-12-15. I treat the ODP block as the canonical starting point per instructions, but the live record controls, and I flag this as an ODP ingest gap. I could not retrieve the actual Final Written Decision because none ever issued — the trial ended by adverse judgment first.

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Proceedings overview

One AIA trial proceeding on file for US 11,435,542: IPR2024-01227 (CommScope Technologies LLC v. Belden Canada ULC), filed 2024-07-26, instituted 2025-02-27, terminated 2025-09-08 by adverse judgment after the patent owner statutorily disclaimed every challenged claim. Breakdown: 0 active, 1 claims-invalidated/adverse-judgment, 0 claims sustained, 0 settled, 0 institution denied. Bottom line for a defendant: claims 1–5 and 8–13 are disclaimed and canceled — if a demand letter or complaint cites any of them, it cites dead claims. Only dependent claims 6 and 7 nominally survive, and both depend from disclaimed claim 1.

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IPR2024-01227 — CommScope Technologies LLC v. Belden Canada ULC

• Type: Inter Partes Review (35 U.S.C. §§ 311–319)
• Filed: 2024-07-26 (USPTO docketing/notice date 2024-09-24)
• Status: "Terminated-Adverse Judgment" (per IPR Verse / PTAB case record) — i.e., post-institution adverse judgment entered against the challenged claims under 37 C.F.R. § 42.73(b)(2) after Patent Owner disclaimed them. An inter partes review certificate (K1) issued 2025-12-15.
• Judge panel: Panel Change Order entered 2025-05-30 (by Deputy Chief APJ Jacqueline Wright Bonilla) replaced APJ Josiah C. Cocks with APJ Jameson Lee. Final panel of record: Administrative Patent Judges Jameson Lee, Christopher M. Kaiser, and Kimberly McGraw. (The Feb. 27, 2025 institution decision predates the panel change; all prior orders remained in effect.)
• Petition grounds — petition challenged claims 1–5 and 8–13 (all claims except 6 and 7):
  • Ground 1 — § 103 obvious over Fukui alone or Fukui + Sedor (claims 1–5, 8–13)
  • Ground 2 — § 102 anticipation by Fukui (claims 8–13)
  • Ground 3 — § 103 obvious over Sauter alone (claims 1–5, 8, 10–13)
  • Ground 4 — § 103 obvious over Sauter + Fukui (claims 1–5, 8, 10–13)
  • Ground 5 — § 103 obvious over Ground 3/4 further combined with Sedor (claims 1–5, 8, 10–13)
  • Supporting art: U.S. 10,101,551 ("Fukui"); U.S. 10,215,944 ("Sedor"); U.S. 9,690,064 ("Sauter"); plus secondary references (Fabrykowski, Blackwell, Laarveld/NL2008155C2, EIA/ECA-310-E, IEC 61754-20). Expert: Dr. Stephen Ralph. No § 112 grounds were raised in the IPR (indefiniteness of "standard width unit" was litigated in the district court instead).
• Institution decision: Instituted 2025-02-27 — granted review on all grounds and all challenged claims (37 C.F.R. § 42.108(a)). On the key dispute, the Board credited Petitioner's reading that Fukui's "conversion module 20," formed by coupling unit modules 10A/10B, is a cassette of double width — "the current record reasonably suggests that the conversion module 20 is a component analogous to conversion module 10, but with a larger width, i.e., two times the width." The Board found the preamble and undisputed limitations of claim 1 (and the analogous claim 8 limitations) would have been obvious over Fukui or Fukui + Sedor. Patent Owner's § 325(d) / Advanced Bionics discretion argument and its "different widths" distinction did not carry the day at institution. Patent Owner's Preliminary Response was filed 2024-12-02.
• Final Written Decision: None issued. The trial terminated before the FWD. On 2025-05-21 Patent Owner filed a Non-Contingent Motion to Amend (Eldering declaration) proposing substitute claims and moving to cancel all challenged claims. On 2025-08-07 Patent Owner filed a statutory disclaimer of claims 1–5 and 8–13 (effective date 2025-07-17 per the patent record) and moved to withdraw the MTA and terminate. By Order dated 2025-08-04, the Board authorized the withdrawal and termination with adverse judgment entered against the claims challenged in the petition (37 C.F.R. § 42.73(b)(2)). Adverse judgment entered 2025-09-08. Claim-level disposition: claims 1–5 and 8–13 canceled/disclaimed; claims 6 and 7 were never challenged and never adjudicated.
• Settlement / termination: Not a settlement. Petitioner expressly put on the record that "there has been no settlement." Termination was by the Board's adverse-judgment order, not by settlement and not by a merits FWD.
• Appeal: No Federal Circuit appeal of IPR2024-01227 located. Caution: there is a Fed. Cir. appeal captioned Belden Canada ULC v. CommScope, Inc., Nos. 2026-1255 / 2026-1285, but that appeal arises from D. Del. No. 1:22-cv-00782-RGA — a different case — and was dismissed under Fed. R. App. P. 42(b) on 2026-06-29; it is not an appeal of this IPR. Treat the IPR as unappealed based on the record I could verify.
• Defensive value: This patent is effectively dead for assertion purposes. Claims 1–5 and 8–13 are statutorily disclaimed and canceled via adverse judgment — an infringement theory built on claim 1 or claim 8 is a non-starter and arguably sanction-bait. Claims 6–7 survive only formally: both depend from disclaimed claim 1, so they are not practically enforceable. Note that this is the same petitioner (CommScope) running a coordinated four-IPR campaign (IPR2024-01218, -01227, -01228, -01382) against Belden's four asserted patents, and all four terminated by adverse judgment.

Primary sources:

• Petition (Ex. list, Grounds 1–5) — USPTO PTACTS: https://ptacts.uspto.gov/ptacts/public-informations/petitions/1556426/
• Institution Decision 2025-02-27 (Excerpt, "we institute on all grounds and all claims raised in the Petition") — USPTO PTACTS: https://ptacts.uspto.gov/ptacts/public-informations/petitions/1556426/download-documents?artifactId=R3Pb0HKcn1Gfzofh4fcHseRkaXsWvYuqMaQbHiNpovAYE9ajp5CrrB0
• Board Order (2025-08-04) authorizing withdrawal of MTA and termination with adverse judgment (covers all four IPRs): https://ptacts.uspto.gov/ptacts/public-informations/petitions/1556612/download-documents?artifactId=aIE8uPDCizdHebQ0CDVrB6vvHUIhV1nsH2gk3phaJ1B7AmeD2kv7u2s and Docket Alarm: https://www.docketalarm.com/cases/PTAB/IPR2024-01228/CommScope_Technologies_LLC_v._Belden_Canada_ULC/
• Panel Change Order 2025-05-30: https://www.docketalarm.com/cases/PTAB/IPR2024-01228/CommScope_Technologies_LLC_v._Belden_Canada_ULC/05-30-2025-Board/Order__Other-12-Panel_Change_Order/
• Case record (status, institution date, termination date, certificate): https://ipverse.greyb.com/ptab-web/cases/case-details/IPR2024-01227
• Patent-level legal events (IPR filed, disclaimer of claims 1–5 / 8–13 effective 2025-07-17, IPR certificate issued 2025-12-15): https://patents.google.com/patent/US11435542/en
• Related district court stay: Belden Canada ULC v. CommScope, Inc. et al., No. 1:23-cv-00810-RGA (D. Del.), stayed 2024-09-04 (D.I. 63), administratively closed.

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Strategic summary

Claim status on the face of the patent. The '542 patent issued with 13 claims. Claims 1–5 and 8–13 are canceled — first by Patent Owner's statutory disclaimer (effective 2025-07-17), then confirmed by the Board's adverse judgment (2025-09-08) and memorialized in the 2025-12-15 IPR certificate. Claims 6 and 7 are UNTESTED — never challenged, never construed, never adjudicated — but both are dependent on claim 1, which is disclaimed, so they inherit claim 1's limitations and have no independent scope. There are no "sustained" claims; nothing survived on the merits. In short: if an assertion quotes claim 1, claim 4 ("four receptacles per standard width unit"), claim 7 (cable-management bracket), or method claim 8, the assertion is aimed at canceled subject matter.

Estoppel landscape. Under 35 U.S.C. § 315(e)(2), CommScope (and its RPIs/privies) is estopped in the district court from asserting any ground it raised or reasonably could have raised in IPR2024-01227 — that is, the Fukui, Sedor, Sauter, and secondary-reference theories. For a different defendant, § 315(e)(2) estoppel does not attach (it runs only against the petitioner/privies). The practical upside, however, is that the whole IPR record — the Ralph declaration, the Fukui/Sedor/Sauter claim charts, the Board's institution reasoning on the "widely-coupled modules = 2W cassette" theory — is now public and free to reuse, and the art is no longer "new." A new defendant therefore has a ready-made invalidity narrative if any surviving claim (6 or 7) were ever asserted, with no estoppel exposure to the IPR grounds. Note the Board's view is instructive: Petitioner argued, and the Board preliminarily agreed, that Fukui's coupled unit modules disclose the claimed "different width" cassettes — a theory that cuts directly at the core width-unit limitation in every independent claim.

Pattern signals. This was a multi-patent campaign, not a one-off: CommScope filed four coordinated IPRs on Belden's four asserted patents — IPR2024-01218 (US 10,795,107), IPR2024-01227 (US 11,435,542), IPR2024-01228 (US 11,656,422), IPR2024-01382 (US 11,740,423) — and the Delaware case was stayed 2024-09-04 pending their resolution. Rather than litigate to four FWDs, Belden disclaimed all challenged claims across all four proceedings in July–August 2025, and the Board entered adverse judgments in every one (Sept. 8, 2025). Two signals matter going forward: (1) Belden's hedging strategy — it reported newly issued same-family patents US 12,313,896 and US 12,332,491, filed a second infringement suit on those, and filed continuation 19/239,502 (published US2025/0306324A1) carrying forward the substitute-claim concepts from the withdrawn motions to amend. CommScope objected on the record that nothing in the amendments/new patents is patentably distinct from the disclaimed claims — i.e., expect a patentably-distinct / obviousness-type double-patenting fight if the follow-on patents are asserted. (2) No defensive aggregator (e.g., Unified Patents) is in the chain for this proceeding — the petitioner of record is CommScope, an operating competitor defending a commercial dispute, notwithstanding the "Unified Patents PTAB Data" attribution string that appears in the Google Patents litigation feed (that is a data-source credit, not the petitioner).

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Recommended next steps

• If you are a defendant and a demand letter or complaint cites claims 1–5 or 8–13 of US 11,435,542: the claims are canceled. Point to the Board's 2025-08-04 Order authorizing "termination of the proceedings with adverse judgment entered against the claims that were challenged in the petition," the 2025-09-08 adverse judgment, the Patent Owner's 2025-08-07 statutory disclaimer (effective 2025-07-17), and the IPR certificate issued 2025-12-15. Any theory built on claim 1 or claim 8 has no legal footing.
• If you are the same party or in privity with CommScope, note that § 315(e)(2) estoppel now bars the IPR grounds (and grounds reasonably could have been raised) in any civil action — plan invalidity positions accordingly.
• If the patentee pivots to claims 6 or 7: these are the only nominal survivors, and both depend from disclaimed claim 1, so (a) demand a theory of how a dependent claim survives a disclaimed parent, and (b) note the full IPR record is available as prior-art/obviousness material.
• No active proceeding to track. IPR2024-01227 is terminated; there is no institution deadline, oral hearing, or statutory FWD date outstanding (the § 316(a)(11) one-year deadline from the 2025-02-27 institution would have fallen ~2026-02-27, but the trial ended by adverse judgment on 2025-09-08). No CAFC appeal of this IPR was located.
• Watch the family, not this patent. The commercial dispute continues through the newly issued US 12,313,896 and US 12,332,491, continuation 19/239,502 (US2025/0306324A1), and the earlier US 10,795,107 / US 11,656,422 / US 11,740,423 — all of which were also subject to adverse judgment in the parallel IPRs. Run your FTO/clearance against those claims; the '542 claims themselves are spent.
• Verify with primary documents: PTAB E2E / PTACTS case page for IPR2024-01227 (https://ptacts.uspto.gov/ptacts/public-informations/petitions/1556426/) and the PTAB adverse-judgment paper (2025-09-08) before relying on any of the above in a brief.

Caveats. I did not locate a publicly posted Final Written Decision for IPR2024-01227 and I state explicitly that none issued — the disposition was an adverse judgment, not an FWD. I could not independently verify the exact APJ panel that issued the 2025-02-27 institution decision (the panel changed on 2025-05-30); I have not guessed it. Ground-by-ground claim mapping is taken from the petition's own Grounds table (Ground 5 in the petition's table is internally worded "Either of Grounds 4 or 5," which appears to be a drafting slip for "Grounds 3 or 4"; I have preserved the petition's numbering). Any item I could not confirm from a primary source is flagged as such above rather than asserted.

I'll research the assignment record, litigation, and any correspondent data before drafting.

Let me check the assignment records' correspondent data and the Belden corporate status.

Assignment & Ownership Analysis — US 11,435,542 B2

Patent: Modular fiber optic cassette, system and method
App. No.: 17/010,113 (filed 2020-09-02; continuation of 16/143,831, now US 10,795,107; priority to provisional 62/567,339, 2017-10-03)
Issued: 2022-09-06 | Current assignee of record: Belden Canada ULC
Verification: USPTO Assignment Center search by patent number — https://assignmentcenter.uspto.gov/ (also https://assignment.uspto.gov/patent/index.html)

Data caveat: The records below are drawn from the patent's Google Patents legal-events table (which mirrors the Assignment Center reel/frame entries), the prosecution record, and PTAB/docket filings. The recorded correspondent attorney name on the assignment covers themselves was not retrievable in this session — I flag each entry accordingly rather than guess. The prosecution correspondence of record is known (Lavery, De Billy, LLP, Hugh Mansfield, Montreal) and is noted where relevant.

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Inventors

• Sole named inventor on the '542 patent and across the continuation family ('107, '422, '423, and the pending 2025 application).
• No anomalous departure pattern. Pilon did not exit the assignee; the portfolio was continuously prosecuted by Belden from 2018 through 2025, the inventor's assignment was taken nunc pro tunc to 2018-10-01, and there is no evidence of inventor-side spin-out or portfolio fire-sale.
• The family's continuation chain (five active/later US filings, all sharing the 2017-10-03 priority) confirms the original assignee retained and expanded the portfolio rather than divesting it.

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Original assignee

Belden Canada ULC (Saint-Laurent, Quebec, Canada), applied-for and issued as assignee; original corporate assignor was Belden Canada Inc., its predecessor within the Belden group.

• Primary line of business: Network infrastructure / connectivity — fiber optic cassettes, patch panels, copper and fiber cabling, industrial networking. Part of Belden Inc. (NYSE: BDC), publicly traded. Belden Inc. is identified as a real party-in-interest in the PTAB proceedings.
• Shipped a product embodying the claims: Yes. The '542 family covers Belden's modular high-density fiber cassette/tray platform (the "standard width unit" cassette architecture). Belden asserted these patents against a competitor's competing modular panel system (CommScope Propel) — the classic posture of an operating company enforcing a product it sells.
• Current status: Operating. No bankruptcy, dissolution, or acquisition of the assignee. Belden Canada ULC is the live owner of record and continues to file continuations (latest: 19/239,502, published as US 2025/0306324 A1).

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Assignment timeline

All recorded activity in this chain is intra-Belden. There is no assignment to any third party, LLC, or holding/licensing entity anywhere in the '542 record.

• 2018-10-01 (executed, nunc pro tunc) / recorded 2020-09-02 — Reel 053673/0222

  • Conveyance: Assignment (recorded as NUNC PRO TUNC ASSIGNMENT)
  • Assignor: Vincent Pilon (Lachine, Canada)
  • Assignee: Belden Canada Inc.
  • Correspondent: not stated in the events data available to me. The prosecution/PTO correspondence of record for this family is Lavery, De Billy, LLP, 1 Place Ville Marie, Suite 4000, Montreal, QC H3B 4M4, Canada (Hugh Mansfield) — a Belden outside-prosecution firm, not an NPE recording agent. Flag: this is an operating-company prosecution firm, and it recurs on the family's later PTAB correspondence; it is not a shell-entity recording service.
  • Context: Inventor-to-employer assignment — routine patent-perfecting assignment of the employee inventor's rights to the operating company.

• 2018-10-01 (executed, nunc pro tunc) / recorded 2020-09-17 — Reel 053804/0725

  • Conveyance: Assignment (NUNC PRO TUNC ASSIGNMENT)
  • Assignor: Vincent Pilon
  • Assignee: Belden Canada Inc.
  • Correspondent: not stated in available events data (same caveat; see entry above).
  • Context: Corrective / duplicate recording of the original inventor assignment — the same Pilon→Belden Canada Inc. transfer was re-recorded in September 2020 alongside the entity reorganization. Not a new economic transaction.

• 2020-03-20 (executed) / recorded 2020-09-17 — Reel 053804/0953

  • Conveyance: Assignment (ASSIGNMENT OF ASSIGNORS INTEREST)
  • Assignor: Belden Canada Inc.
  • Assignee: Belden Canada ULC
  • Correspondent: not stated in available events data (same caveat).
  • Context: Internal corporate reorganization / change of legal entity — the operating business was moved from Belden Canada Inc. to Belden Canada ULC within the same corporate group. No change of beneficial owner or business; this is the classic "Inc. → ULC" internal restructuring, not a divestiture.

No post-issuance assignment of any kind has been recorded. The last recorded transfer is the 2020 intra-group reorg; Belden Canada ULC has owned the patent since. A companion event on the record — the 2025 statutory disclaimer (below) — is not an assignment.

Related non-assignment legal events (context, not transfers):

• 2023-07-27 / 2023-08-30 — Belden Canada ULC sues CommScope, Inc., CommScope, Inc. of North Carolina, and CommScope Technologies LLC, D. Del. 1:23-cv-00810-RGA, asserting the '107, '542, '422, and '423 patents.
• 2024-09-24 — IPR2024-01227 instituted against the '542 patent (filed by CommScope 2024-07-26; institution 2025-02-27; terminated Adverse Judgment, 2025-09-08).
• 2025-08-26 (effective 2025-07-17) — Statutory disclaimer filed disclaiming complete claims 1–5 and 8–13 of the '542 patent (leaving only claims 6 and 7).
• 2025-12-15 — IPR certificate issued (Trial No. IPR2024-01227), recording the outcome against US 11,435,542.

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Timeline diagram

timeline
    title Ownership of US 11435542
    2017 : Provisional filed by Vincent Pilon
    2018 : Pilon assigns rights to Belden Canada Inc
    2020 : Belden Canada Inc moves assets to Belden Canada ULC
         : Continuation application filed
    2022 : Patent issued to Belden Canada ULC
    2023 : Belden sues CommScope in Delaware
    2024 : CommScope petitions for IPR 2024-01227
    2025 : Belden disclaims claims 1 through 5 and 8 through 13
         : IPR terminated by adverse judgment

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NPE / troll-pattern signals

Note on the IPR asymmetry: The PTAB challenge was brought by CommScope (IPR2024-01227), not by Unified Patents, and it terminated by adverse judgment — Belden then disclaimed claims 1–5 and 8–13. This is a validity/defensive posture in a competitor-vs-competitor fight, the opposite of NPE assertion behavior.

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Verdict

Operating-company assertion.

Belden Canada ULC — the issued-and-current assignee of record and a unit of publicly traded Belden Inc. (NYSE: BDC) — is the original applicant that built and sells the modular cassette product embodying the claims, and it is directly suing its competitor CommScope in D. Del. 1:23-cv-00810-RGA on the '542 and three sister patents. The entire recorded chain is internal to Belden: Pilon → Belden Canada Inc. (Reels 053673/0222 and 053804/0725, the same inventor assignment recorded twice) and Belden Canada Inc. → Belden Canada ULC (Reel 053804/0953, a 2020 intra-group reorganization). Zero NPE signals are present — no shell LLC, no known asserter, no cascading transfers, no pre-litigation assignment, no fire-sale, no privateering, and no defensive-aggregator termination. This is a genuine operating company enforcing a product patent; the only dramatic event is the 2025 statutory disclaimer of claims 1–5 and 8–13 following the IPR2024-01227 adverse judgment.

Verify: USPTO Assignment Center — https://assignmentcenter.uspto.gov/ (search "11435542"); the three reel/frame entries above.

I'll verify the key prior-art references cited on the face of US 11,435,542 before analyzing them against the claims.

Let me verify a few more of the cited references.

Prior-Art Analysis — US 11,435,542 B2

"Modular fiber optic cassette, system and method" — App. 17/010,113; filed 2020‑09‑02; priority 2017‑10‑03; issued 2022‑09‑06; inventor Vincent Pilon; assignee Belden Canada ULC.

Scope note (literal identifiers): I searched the specific number 11435542 / 11,435,542. The prior-art set below is the citation list appearing on the face of US 11,435,542 B2 (Google Patents "Citations (23)" / "Patent Citations (29)"), which is the authoritative source supplied in the patent text. I did not substitute or auto-correct any reference number. Where the record uses both an application publication and the granted patent of the same family (e.g., US 2018/0003912 A1 → US 10,215,944 B2), I treat them as one reference family and say so.

Critical cross-reference: per the previously generated sections, claims 1–5 and 8–13 were statutorily disclaimed (effective 2025‑07‑17) after IPR2024‑01227 terminated in adverse judgment. That reshapes the § 102 analysis: the independent claims that the cited art would map to (1 and 8) are no longer in force. The only claims arguably still live are claims 6 and 7, which depend from disclaimed claim 1. I therefore give the mapping for completeness, but I flag at the end that none of the cited references appears to disclose the specific subject matter of claims 6 or 7.

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1. Which cited references even qualify as § 102 prior art

Priority is October 3, 2017. A cited reference can only be § 102 art if it predates that (or is a US application/patent with an earlier effective filing date under § 102(a)(2)). Sorting the face-of-patent citations on that basis:

Group A — Enabled as § 102 prior art (pre‑2017‑10‑03):

Group B — NOT § 102 prior art for these claims:

• US 2019/0101717 A1 and US 10,795,107 B2 — these are the parent of the '542 (App. 16/143,831). Same family; cannot be prior art against its own continuation.
• US 2019/0107682 A1 / US 10,359,595 B2 (priority 2017‑10‑05), US 2019/0162924 A1 / US 10,656,359 B2 (2017‑11‑30), US 2019/0187394 A1 / US 10,598,884 B2 (2017‑12‑19), US 11,187,864 B2 (2018‑01‑16), US 10,768,387 B2 (2018‑04‑06) — all Belden filings with effective dates after Oct. 3, 2017; they were cited as related/co-pending family art, not as § 102 references.
• US 10,281,672 B1 (2018‑05‑25), US 10,514,518 B1 (2019‑03‑25) — later priority.
• US 2020/0131730 A1 (Spiro, "Universal pole foundation with instant cap") — filed 2017‑01‑11, but the subject matter (a pole foundation) has no bearing on any claim. It is almost certainly an artifact of a name/field search; I found no technical connection to fiber-optic cassettes.

Dates are taken from the Google Patents full-text record and corroborating aggregator pages; I did not pull every one of these from the USPTO register.

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2. The most relevant references (Group A), with § 102 assessment

A1. Leviton — US 9,690,064 B2, "Multi-gang cassette system"

• Citation: US 9,690,064 B2 (Sauter et al.), filed 2015‑11‑10, granted 2017‑06‑27, appl. 14/937,817; Leviton Manufacturing Co., Ltd. Pre-grant pub. US 2017/0131500 A1. https://patents.google.com/patent/[US9690064B2](/patent/US9690064B2)
• Description: A cassette mounting system that "allows fiber optic cassettes of different sizes to be mounted on the same fiber optic tray," using rail guides engaged by rails on both single-gang and multi-gang cassettes; a spring-loaded latching protrusion engages an aperture in the tray, and a front-facing release latch unlocks the cassette. Multi-gang cassettes have clearance areas so guide rails sit underneath, letting single- and multi-gang cassettes coexist on one tray; trays install in an enclosure. Its PCT search report (PCT/US2016/060907) cited Corning US 2014/226946 A1 as X art.
• § 102 relevance: This is the single closest reference to claim 1 (and to claim 8's method analog). It discloses the case/tray/cassette/fastener architecture and expressly the different-size-cassette coexistence on one tray. Its weakness against claim 1's literal language is the recitation of widths "of one, two, three, four and six standard width units" — Leviton speaks in "gangs," not in a named standard width unit. That gap is the kind of thing that reads as § 103 (different sizes on a common pitch), not clean § 102 anticipation.
• Corroborating materiality: This reference appears in the IPR campaign against this patent family — it is Exhibit 1006 in IPR2024‑01382 (CommScope v. Belden, on sibling US 11,740,423), per the Docket Alarm filing https://www.docketalarm.com/cases/[PTAB](/ptab)/IPR2024-01382/CommScope_Technologies_LLC/docs/08-30-2024-Petitioner/Exhibit-1006-US_Patent_9,690,064_.pdf. I did not independently confirm it was asserted in IPR2024‑01227 itself.

A2. Panduit — US 10,215,944 B2 / US 2018/0003912 A1, "Modular fiber optic tray"

• Citation: US 10,215,944 B2 (Sedor et al.), appl. 15/628,818 filed 2017‑06‑21, granted 2019‑02‑26; priority US provisional 62/356,662, filed 2016‑06‑30; Panduit Corp. Pre-grant pub. US 2018/0003912 A1 (2018‑01‑04). https://patents.google.com/patent/[US10215944B2](/patent/US10215944B2)
• Description: "Modular trays having cutout features that are configured to engage with a mounting feature of one or more removable rails," so a user can install/uninstall rails "to support different sized fiber optic modules. For example, a tray may support a twenty-four optical fiber module, two twelve optical fiber modules, or three eight optical fiber modules." The tray is housed in a fiber-optic enclosure; the tray can be slid.
• § 102 relevance: Directly on the "different-sized modules on one tray" pivot of claim 1, and it recites specific module widths (8/12/24-fiber) that map to the '542's 2W/3W/6W nomenclature. The differentiator is mechanical: Panduit reaches mixed sizing by repositioning rails, whereas the '542 keeps fixed slot/aperture spacing on a standardized pitch. Assessed as strong § 103 art; § 102 anticipation of claim 1 is arguable but not clean, because Panduit does not recite a "standard width unit" that all cassette widths are integer multiples of.

A3. AFL — US 2019/0004268 A1, "High density patch panel with modular cassettes"

• Citation: US 2019/0004268 A1 (Vogel), appl. 15/971,477 filed 2018‑05‑03, published 2019‑01‑03; priority 2017‑06‑27 (and 2017‑11‑28 provisional 62/590,823 per the related family); AFL Telecommunications LLC (parent: Fujikura). https://patents.google.com/patent/US20190004268A1
• Description: A patch panel with a tray slidable between retracted and extended positions on tray supports, the tray having a plurality of cassette mounting bays; cassettes are slidable on cassette supports and held by latches with a release slide allowing removal from front and back. Cassettes include LC and MPO connectors at front and rear, with internal fibers.
• § 102 relevance: Establishes, before the '542 priority date, a rack-mount enclosure + sliding tray + modular cassettes + latch fastener architecture with front/rear connectors — the general scaffold of claim 1 and, for the fiber-routing interior, claim 3. By itself it does not teach the mixed/standard-width-unit selection, so it is better characterized as § 103 combinable art than a standalone § 102 reference.

A4. Corning — US 9,075,216 B2, "Fiber optic housings configured to accommodate fiber optic modules/cassettes and fiber optic panels…"

• Citation: US 9,075,216 B2 (Cote, Frazier, Giraud, Jay, Rodriguez), appl. 12/940,585 filed 2010‑11‑05, granted 2015‑07‑07; priority 2009‑05‑21 (and provisionals incl. 61/180,331); Corning Cable Systems LLC. https://patents.google.com/patent/[US9075216B2](/patent/US9075216B2)
• Description: A fiber optic housing/shelf that supports fiber optic modules/cassettes and fiber optic panels interchangeably via removable panel clips; the shelf inserts into a housing and the housing into an equipment rack. It expressly teaches that the mounting surface "may also be configurable to support one or more fiber optic modules and one or more fiber optic panels interchangeably" (its claims 2, 31).
• § 102 relevance: Anticipates the interchangeability concept underlying claim 1 (different equipment types on one housing/tray) and the rack-mount aspect of claim 5. It does not disclose cassettes whose widths are integer multiples of a standard width unit, so not clean § 102 for claim 1.

A5. Corning — US 8,913,866 B2, "Movable adapter panel"

• Citation: US 8,913,866 B2 (Cote et al.), appl. 12/732,487 filed 2010‑03‑26, granted 2014‑12‑16; Corning Cable Systems LLC. https://patents.google.com/patent/US8913866
• Description: A support shelf with a plurality of component mounting features (openings/slots) that permit "releasably mounting of fiber optic hardware at a plurality of locations on the support shelf," from flush to recessed. Adapter panels "including a fiber optic adapter panel that is part of a fiber optic module or cassette" are mounted at any of the predetermined locations; shelf supports engage a housing/rack so the shelf is movable.
• § 102 relevance: Discloses the "fastener"/releasable-mounting and repositionable-hardware aspects of claim 1 and a movable shelf inside a housing. Not directed to mixed cassette widths.

A6. Corning — US 2016/0062068 A1 and US 2016/0062050 A1, "Fiber optic solutions for migration between duplex and parallel multi-fiber solutions…"

• Citation: US 2016/0062068 A1 and US 2016/0062050 A1 (filed 2014‑08‑29; published 2016‑03‑03); Corning Optical Communications LLC. (Both appear on the '542 face; US 2016/0062068 A1 carries the examiner-citation asterisk.)
• Description: Modules/solutions for migrating between duplex connectors (SC/LC duplex) and parallel multi-fiber (MPO) architectures "allowing for full fiber utilization," i.e., converting MPO trunks into discrete duplex ports within a module.
• § 102 relevance: Most closely relates to claim 4 ("four fiber optic plug receiving receptacles… for each standard width unit" — i.e., the LC-quad / SC-duplex footprint on which the '542's W unit is based) and to claim 3 (rear multi-fiber connector feeding a row of front receptacles). It does not disclose the standardized-pitch mixed-width tray.

A7. The remaining Group A references (§ 102/§ 103 background art)

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3. Claim-by-claim § 102 summary

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4. Bottom line and caveats

1. The most relevant prior art on the face of US 11,435,542 is, in order: (i) US 9,690,064 B2 (Leviton, multi-gang cassette system), (ii) US 10,215,944 B2 / US 2018/0003912 A1 (Panduit, modular fiber optic tray), and (iii) US 2019/0004268 A1 (AFL, high-density patch panel with modular cassettes). These are the references that actually confront the "cassettes of different sizes mounted side-by-side on one tray" concept of independent claim 1, and the Leviton reference is the same document that appears as an exhibit in the parallel IPR campaign against this patent family.
2. No cited reference is a clean, single-document § 102 anticipation of claim 1 or claim 8 as literally worded, because none recites cassette widths as integer multiples of a named "standard width unit." They are best characterized as § 103 art (or as anticipatory only under a broad construction of that phrase).
3. Neither surviving-by-default claim (6, magnet fastener; 7, width-unit cable-management bracket) is anticipated by any cited reference. That matters because — per the earlier section — claims 1–5 and 8–13 were disclaimed effective 2025‑07‑17 following the IPR2024‑01227 adverse judgment, leaving 6 and 7 as the only non-disclaimed claims, and their scope incorporates the limitations of the disclaimed claim 1.
4. This mapping is prospective/historical rather than a current invalidity defense: because the claims the cited art attacks are now disclaimed, the § 102 analysis above has greatest practical significance for the later sibling continuation patents (US 11,740,423, US 12,313,896, US 12,332,491), which share this disclosure and carry closely related claims.

Verification caveats: Bibliographic and legal-events data are drawn from the Google Patents full-text record and corroborating aggregator pages (Google Patents, Justia, Docket Alarm, GreyB IPVerse). I did not independently retrieve the IPR2024‑01227 petition or the K1 certificate, and I have not verified which specific references CommScope relied on in IPR2024‑01227; the Leviton reference is confirmed as Exhibit 1006 only in the sibling IPR2024‑01382. The § 102/§ 103 characterizations are my own technical reading, not an authoritative USPTO or court holding.

I'll pull the actual prior-art grounds used against this patent and verify the reference details before constructing the §103 analysis.

Let me identify the actual primary references (Fukui, Sauter) and the remaining exhibit list from the petition.

Let me confirm the specific grounds in the '542 petition itself and the institution decision.

Obviousness Analysis — U.S. Patent No. 11,435,542 B2

"Modular fiber optic cassette, system and method" (Belden Canada ULC; appl. 17/010,113)

Analytical frame. I apply the Graham v. John Deere factors as restated in KSR Int'l Co. v. Teleflex Inc., 550 U.S. 398 (2007), using (a) the references cited on the face of the '542 patent ("Prior Art" section of the Google Patents record), and (b) the references actually applied in the only PTAB challenge to this patent, IPR2024‑01227 (CommScope Techs. LLC v. Belden Canada ULC, filed July 26, 2024).

Two threshold flags before the merits

1. Date discrepancy: this task header says "Current Date: April 26, 2026," while my session metadata says 2026‑09‑28. Nothing in the §103 analysis turns on which is correct — every material event (IPR institution 2025‑02‑27, disclaimer effective 2025‑07‑17, adverse judgment 2025‑09‑08, IPR certificate 2025‑12‑15) predates both.
2. Most of the claims no longer exist. Per the legal-events table on the '542 record, Belden filed a statutory disclaimer of complete claims 1–5 and 8–13 (recorded 2025‑08‑26, effective 2025‑07‑17), and the Board entered adverse judgment on those claims on 2025‑09‑08 (IPR2024‑01227 terminated). Google Patents records the resulting IPR certificate (K1) with effective date 2025‑12‑15. Consequently, claims 6 and 7 are the only claims that remain in force, and they depend from the now‑disclaimed claim 1. I analyze all thirteen claims as issued (for completeness and because a district court may still face the disclaimed claims' effect on scope), but I separate the live claims 6–7 for close attention, because — critically — they were never challenged in the IPR (the petition challenged only claims 1–5 and 8–13).

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1. Critical date, governing law, and POSITA

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2. Scope and content of the prior art

2A. References on the face of the '542 patent (the "Prior Art" section)

Not prior art, despite appearing in the family/related lists: US 2019/0101717 A1 is Belden's own parent publication (same inventive entity/priority chain), and US 11,947,432 (AFL, 2019), US 12,298,583 / US 12,468,107 (CommScope, 2019/2021) and US 2025/0306324 A1 are later family members or later filings — none can be used against the '542 claims.

2B. References introduced by the IPR petitions (key additions)

Stated grounds in IPR2024‑01227 (per Belden's Preliminary Response): five grounds — Grounds 1–2 on Fukui (alone; Fukui + Sedor), Grounds 3–5 on Sauter (alone; Sauter + Fukui; Sauter + Fukui + Sedor). Institution was granted on all grounds and all claims on Feb. 27, 2025. Sources: https://ptacts.uspto.gov/ptacts/public-informations/petitions/[1556426](/patent/1556426)/download-documents?artifactId=sscF0Y86LDeYAGW94YcH0O0ObBv0OIpyvO7_EvJnRBNMmXVf8DqeGW4 (Belden POPR); https://ipverse.greyb.com/ptab-web/cases/case-details/IPR2024-01227 (case status).

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3. What the Board actually did and did not decide

This matters enormously for how much weight a §103 opinion can carry here:

• The Feb. 27, 2025 institution decision found a reasonable likelihood that claims 1–5 and 8–13 are unpatentable, and it made specific, quotable findings. The Board held that Fukui's "conversion module 20" — two coupled "unit modules" — is properly regarded as "a component analogous to conversion module 10, but with a larger width, i.e., two times the width," expressly noting that Fukui calls both components "conversion module." It also found Petitioner "sufficiently demonstrates… that the preamble of claim 1 and the undisputed limitations would have been obvious… in light of Fukui or the combination of Fukui and Sedor," and that for claim 8 "Petitioner shows sufficiently that Fukui teaches the disputed limitation." Excerpt: https://ptacts.uspto.gov/ptacts/public-informations/petitions/1556426/download-documents?artifactId=R3Pb0HKcn1Gfzofh4fcHseRkaXsWvYuqMaQbHiNpovAYE9ajp5CrrB0
• But there is no merits adjudication. The proceeding ended because Belden disclaimed the challenged claims and, under 37 C.F.R. § 42.73(b)(2), that disclaimer was treated as a request for adverse judgment (the Board's authorization order consolidated all four IPRs). Order: https://ptacts.uspto.gov/ptacts/public-informations/petitions/[1556612](/patent/1556612)/download-documents?artifactId=aIE8uPDCizdHebQ0CDVrB6vvHUIhV1nsH2gk3phaJ1B7AmeD2kv7u2s
• Legal effect: a §253(a) disclaimer is a forfeiture, not a validity holding. The disclaimed claims are treated as though they never existed; they cannot be asserted. Dependent claims 6–7 were not part of the disclaimer and were not challenged, so they are the only live claims — but their scope incorporates every limitation of claim 1 (my reading, consistent with the earlier section of this analysis; I have found no authoritative ruling on the point for this patent).

Practical consequence for a §103 opinion: attacking claims 1–5 and 8–13 today is academic. The only commercially meaningful §103 target is claims 6–7, and the strongest attack on them is not their own added features (which are weak) but the inherited claim 1 limitations — including the "standard width unit" term that CommScope contends is indefinite.

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4. Claim 1 — element-by-element

Two independent grounds are available; I present them side by side because they are legally distinct and have different strengths.

Assessment: Claim 1's only genuinely novel-sounding feature is the arithmetic relationship between cassette widths — each being an integer multiple of a common unit so that mixed sizes tile a tray without waste. Every physical component (case, sliding tray, front-row receptacles, mixed-width cassettes on one tray, tool-less fastener, edge-to-edge mounting) is independently disclosed in Sauter and Fukui, both of which are in the same field and address the same problem. That is the classic KSR "combination of familiar elements according to known methods… when a patent simply arranges old elements with each performing the same function it had been known to perform" (KSR, 550 U.S. at 415–17). I would rate Grounds A and B as strong on claim 1, subject to the two genuine vulnerabilities in §5 below.

Dependent claims 2–5 (all now disclaimed)

Method claims 8–13 (all now disclaimed)

Claims 8–13 recite the same subject matter as method steps and add nothing structural. The Board held Petitioner "sufficiently demonstrates… that the preamble of claim 8 and the undisputed limitations would have been obvious over Fukui or over the combination of Fukui and Sedor." Specifics:

• Claim 8 — "defining a standard width unit…"; "selecting a plurality of cassettes… each of said different widths is evenly divisible by said standard width unit"; "releasably securing." Fukui's tray is drilled at a uniform 1W pitch, so using the tray is inherently defining and applying the unit; Sauter frames the same exercise as a design method ("system allows cassettes of different sizes to be mounted on the same tray… at any position"). In re Kollar-type reasoning — reciting the intended use of a known apparatus as a method step — supports obviousness.
• Claim 9 (widths 1, 2, 3, 4, 6) — Fukui's 1W/2W/3W/4W plus the predictable 6W extension (3×2W/2×3W; 72-core cable). Note the Sauter grounds in the '542 IPR covered claims 1–5, 8, 10–13 but not claim 9 — the width menu is a Fukui-side disclosure.
• Claim 10 (all same width) — Fukui Fig. 8 (twelve 1W modules); Sauter (gangs used together).
• Claim 11 (first and second different widths) — the core mixed-width teaching of Fukui module 20 and Sauter's gang sizes; Laarveld for adjacency.
• Claim 12 (third, different width) — Fukui's 36-core (3W) alongside 2W; Sauter's triple-gang alongside single/double.
• Claim 13 (front edge divisible by at most 12 units) — Fukui's 12-module tray.

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5. The two genuine weaknesses in the §103 case (and why the Board still instituted)

A credible opinion must state the counters, because Belden pressed both and the Board's institution decision is only a "reasonable likelihood" finding.

(i) "Fukui's module 20 is not a cassette of a different width — it is two cassettes coupled together." Belden argued that Fukui "only discloses one type of cassette: a single 'standard width unit'" and that "coupling two (or three) cassettes does not result in a single cassette." The Board rejected this at the institution stage, reasoning that Fukui itself calls both component 10 and coupled component 20 a "conversion module," and that component 20 is therefore "a component analogous to conversion module 10, but with a larger width." This is a fact question about whether the prior art discloses a unitary structure of twice the width, and it is the point on which a district court could go the other way. Mitigation: the Sauter ground does not depend on it — Sauter discloses purpose-built single-, double-, and triple-gang cassette housings.

(ii) Sauter's double-gang cassette is "approximately" twice the width, not exactly. Sauter's own specification says the double-gang cassette is "approximately twice the width of [the] single-gang cassette" because it additionally spans an intermediate rail guide 108D, requiring a "clearance area 602" for latching mechanism 116A. Belden argued this defeats "evenly divisible by said standard width unit" and that Petitioner improperly stretched "cassette width" to include an externally attached latch (Pet. 107–109). The petition's answer was to re-baseline the unit to one-half the width of an 8-port gang, so that all three Sauter gang sizes become exact multiples — a KSR "design choice of the width unit" response.

(iii) The indefiniteness overlay. CommScope's construction — "standard width unit means an actual width that is standardized in the industry, e.g., the width of an SC Duplex footprint" — is a double-edged weapon. If adopted, (a) it may render the term indefinite under §112(b) (the specification gives no dimension, only the relationship W = width of one LC-quad module), and (b) it narrows the mapping to prior art whose cassettes happen to match a real industry footprint. The Joint Claim Construction Chart says this term is "dispositive of all asserted claims." For the live claims 6–7, this is the most dangerous attack of all, because both inherit "standard width unit" from claim 1.

(iv) §325(d) / cumulativeness. Belden argued the Board should deny institution because Sauter was already cited on the face of the '542 patent (US 9,690,064 B2 is in the patent's citation table, marked "cited by examiner"), as was Panduit's Modular Fiber Optic Tray (US 2018/0003912 A1 / US 10,215,944 B2) — i.e., two of Petitioner's references. Advanced Bionics step one therefore favored denial. The Board nonetheless instituted, which tells us it was unpersuaded that the Office substantively addressed Petitioner's particular mapping (mixed-width integer-multiple tiling). But this remains the argument most likely to succeed in a renewed §103 challenge to claims 6–7: the more the new art resembles Sauter/Panduit, the stronger the §325(d) (and district-court "already considered" / KSR hindsight) counterargument.

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6. Motivation to combine — why a POSITA would have done this

A §103 holding requires an articulated reason, not just overlapping disclosures. The following rationales are supported by the record:

1. The references themselves state the problem and the goal. Sauter's abstract: a system that "allows fiber optic cassettes of different sizes to be mounted on the same fiber optic tray… simultaneously at any position." That is functionally the '542's stated object ("fiber optic cassettes of different widths can be arranged on the same tray while optimizing the use of tray space"). Fukui states the goal of supporting cables with "various" fiber counts, expressly listing 36-core and 48-core configurations.
2. "Finite number of identified, predictable solutions." KSR, 550 U.S. at 421. Once the width unit is the LC-quad module (Fukui's 1W) and the tray holds twelve units, the usable whole-number partitions are few; 1/2/3/4/6 are simply the divisors of 12 that correspond to available trunk-cable fiber counts (8/12/16/24 fibers; MPO‑12 and 24-core trunks). Using a 2W, 3W, 4W or 6W cassette on the same 12W tray is "a design choice" made "for the purpose of… providing the desired density," i.e., the predictable use of prior-art elements according to their established functions.
3. Same field, same problem, same form factor. Both Fukui and Sauter are rack-mounted fiber management systems in G02B 6/44. Combining a width-normalized tray (Fukui) with purpose-built multi-gang cassette housings (Sauter) is "the use of a known technique to improve similar devices in the same way," and would have been predictable.
4. Market pressure evidenced by contemporaneous product literature. Leviton's Enclosure & Panel Selection Guide (Ex. 1022), Corning's EDGE HD Solutions (Ex. 1023) and Panduit's HD Flex literature (Ex. 1024), plus the Go!Foton mounting-configuration art (US 2020/0218023), all show the industry converging on modular, removable cassettes in a common panel footprint — the classic "demand… created by market forces" rationale of KSR.
5. Reasonable expectation of success. Every change is mechanical and geometry-only: reuse a known tray, re-drill the mounting holes at a uniform pitch, and provide cassette housings spanning one, two, three, four or six pitches. Fukui already provides exactly this (holes 33a/33b at 1W pitch; hooks 11i/11j enabling tool-less exchange), and Sauter already provides the multi-gang housings. The "test" — do standard cassettes and standard trays snap together and tile the tray? — is simple, and the expected result is certain.
6. Simplicity/no added parts. The '542 itself touts the elegance of "snuggly" tiling with no spacers. A POSITA seeking to avoid leaving unusable tray gaps has a direct incentive to build the arithmetic into the cassette/tray interface rather than use filler plates.

Secondary considerations: I found no evidence in the record of unexpected results, industry praise, licensing attributable to these claims, or long-felt need. The commercial success of the accused CommScope Propel™ product cuts both ways and, absent a nexus to the specific claims, would carry little weight (and in any event the patentee's own family members — US 10,795,107, 11,656,422, 11,740,423, 12,313,896 and 12,332,491 — are the asserted assets in the parallel litigation). Copying is neutral here: CommScope's Propel is a competing architecture, not a copy.

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7. The live claims: 6 and 7

These were not challenged in IPR2024‑01227 and not disclaimed, but each depends from claim 1 and therefore carries all of claim 1's limitations — including "standard width unit," "as measured between outer side edges," and "directly adjacent an outer side edge." That makes them, paradoxically, easier to invalidate on the inherited limitations and harder on their own.

Claim 6 — "tray is manufactured from a ferrous metal and said fastener comprises a magnet"

• Obviousness posture: high. The specification itself presents this as a bare alternative to the tab/slot fastener: "in an alternative embodiment of an assembly for securing the cassettes 32 to the tray 12 the tray 12 is manufactured from a ferrous material such as steel… and the fastener comprises a magnet 66… embedded… within a recess 68 formed in the underside 50 of the cassette 32." An alternative embodiment disclosed as a mere substitution is the paradigm of a §103 design choice: (a) material substitution — a tray of steel instead of molded plastic is a KSR "change in material" with no unexpected property; (b) substitution of a known fastener — magnets are among the oldest tool-less fasteners, and the stated advantage (easy reconfiguration/removal) is the very goal of a modular cassette system; (c) predictable result — magnetic retention of a lightweight cassette on a tray is a simple mechanical relationship with no difficulty of implementation.
• What the record does not contain: I did not find a specific prior-art reference squarely disclosing a magnet-fastened fiber optic cassette, and claim 6 was not in the IPR. So while the legal case under KSR is straightforward, a formal §103 ground would need either (i) a secondary reference showing magnetic mounting in a comparable fiber/tray context (I did not verify one in these results — flagging that as unconfirmed), or (ii) reliance on the specification's own admission that this is a mere alternative embodiment, which is powerful intrinsic evidence of obviousness.
• The sharper attack: because claim 6 inherits claim 1, the "standard width unit" indefiniteness argument (CommScope's construction, "dispositive of all asserted claims") applies with full force. If the term is indefinite, claim 6 falls under §112(b) regardless of the magnet.

Claim 7 — cable-management bracket of one standard width unit with a loop in front of and beside the receptacles

• Obviousness posture: moderately high. The added subject matter is a purely mechanical accessory: "at least one elongate cable management bracket comprising a cable management loop and a fastener for removeably securing said at least one bracket to said tray, said bracket having a bracket width of one of said standard width units… said cable management loop is positioned in front of and to a side of said plurality of optic plug receiving receptacles of said installed cassette."
• Supporting art in the record:
  • US 2009/0290842 A1 (fiber optic splice tray) — fiber routing/retention structures in a tray.
  • US 2016/0033732 A1 (Corning, Fiber optic cable module holder) — holders that retain modules and manage fibers at the module face.
  • US 8,913,866 B2 (Corning, Movable adapter panel) — front-side cable management in a sliding panel.
  • Leviton / Corning EDGE HD / Panduit HD Flex product literature (Exs. 1022–1024) — front cable managers/loops are standard fittings on these panels.
  • The '542's own disclosure — the bracket is described as "other equipment… provided with the same width W and… mounted together with the cassettes 32 to the tray 12," i.e., an accessory on the same modular grid, using the identical fastener (tabs 76 / flexible tab 78 / boss 80) and the identical raised‑shoulder/channel 46/82 alignment as the cassettes.
• Motivation: cable management at the face of a high-density adapter panel is a recognized necessity (a 24-fiber LC-quad cassette presents up to 24 patch cords that must be dressed without violating bend radius). Sizing the bracket to the same width unit is the natural consequence of the tray's modular grid — a KSR "arrangement of old elements" and "design choice" rationale. The novelty, if any, is the arithmetic of its width, not the bracket.
• Counterargument: claim 7 requires the loop to be "in front of and to a side of" the receptacles of an installed cassette — a specific placement. A challenger should be prepared to show a front cable manager located at a lateral edge of the connector field (common in the product literature above). I have not verified a single reference that shows that exact geometry in a modular cassette tray, and flag that as the one element of the whole patent with the least direct art support in this record.

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8. Bottom line

Uncertainty disclosure. (1) I did not retrieve the full IPR2024‑01227 petition or the complete institution decision; my description of the grounds and the Board's rationale is drawn from Belden's Preliminary Response, petition excerpts, the exhibit list and the institution‑decision excerpt reproduced above, and from the parallel '422 and '107 proceedings' filings. (2) I did not verify that JP 6741929 B2 is the Japanese family member of US 10,101,551. (3) I did not locate a specific prior‑art reference disclosing a ferrous‑tray/magnet cassette fastener or the exact claim 7 bracket geometry; those two gaps are the principal limitations on the §103 case for the surviving claims. (4) The surviving‑claim analysis (claims 6–7 living on after claim 1's disclaimer) is my reading of §253 practice, consistent with the earlier section of this analysis, and I have found no authoritative ruling on the point for this patent.