US 5647724

I'll search for authoritative information on US 5,647,724 and check for any CAFC 2026 litigation activity.

Now let me check for any 2026 CAFC docket activity and PTAB/litigation records involving this patent.

Let me do one more targeted check for any Federal Circuit or district court activity citing this patent.

US Patent 5,647,724 — Analyst Summary

Note on identifiers: All numbers below are transcribed literally from the records retrieved. Patent 5647724 = US 5,647,724 (same document, two notations).

1. Bibliographic Data

Assignment/ownership trail (per Google Patents legal events):

• 1996-01-18 — Assignment to Brooks Automation Inc. (inventors Davis & Hofmeister), reel/frame 007770/0234.
• 2017-10-06 — Security interest to Morgan Stanley Senior Funding, Inc. (reel/frame 044142/0258).
• 2025-11-04 — Release of that security interest, recorded in favor of Azenta, Inc. and Azenta US, Inc. (reel/frame 073514/0609), effective 2022-02-01.

⚠️ Uncertainty flag: The "Azenta Inc" entry in the "current assignee" field reflects a release of a security interest, not a plainly recorded conveyance of title. I do not have an authoritative chain-of-title document confirming an outright assignment to Azenta; treat "Azenta" as the listed owner-of-record successor rather than a verified assignee.

2. Abstract (verbatim)

"A substrate transport apparatus having a movable arm assembly, two substrate holders and a coaxial drive shaft assembly. The movable arm assembly has a general X-shaped section that has its center connected to the coaxial drive shaft assembly. The substrate holders are connected to different pairs of arm sections of the X-shaped section. The coaxial drive shaft assembly moves the arms of the X-shaped section relative to each other to move the two substrate holders in reverse unison motion between extended and retracted positions."

3. Technology Context

The patent is directed to a wafer/flat-panel transfer robot for semiconductor processing tools. The three cited prior-art references in the specification are US 4,951,601 (multi-chamber process system), US 5,180,276 (transfer device with two substrate holders), and US 5,270,600 (coaxial magnetic drive shaft assembly, expressly incorporated by reference). A further incorporated-by-reference document is US application 08/421,533, "Articulated Arm Transfer Device" (S-band joint constraint for holder orientation).

The family tree shows this case is the parent of two continuations-in-part: 08/587,087 → US 6,299,404, and 08/786,708 → US 6,231,297. US 6,158,941 and US 6,481,956 also claim the 1995-10-27 priority date. Foreign counterparts: WO 1997015423 A1, EP 0862510 A1/A4 (withdrawn), JP 4063323 B2, KR 100482295 B1, TW 401370 B, AU 7517596 A (abandoned).

4. Independent Claims — Plain-Language Overview

Claim 1 — Apparatus (X-arm architecture, broadly claimed).
A substrate transport apparatus with two components: (a) a movable arm assembly having a "general X-shaped section" whose proximal arms are rotatably connected to each other at the center of the X; and (b) two substrate holders, each attached to a different pair of the X's four ends. This is the broadest claim — it does not require coaxial drive shafts or any specific number of arm members, only the rotatably-pinned X geometry and two holders on separate end-pairs.

Claim 8 — Apparatus (coaxial-drive architecture).
Defined by the drive/arm interface rather than the X-shape label: a coaxial drive shaft assembly with a first (inner) shaft and a second (outer) shaft; a movable arm assembly with four proximal arm sections fixedly connected to that shaft assembly, each extending from the shaft at a different height; the first and third sections fixed to the first drive shaft and the second and fourth sections fixed to the second drive shaft. Substrate holders are connected to the arm assembly. (Of note: this claim limits the holder count only to "substrate holders," not explicitly two.)

Claim 14 — Method (opposed-arm drive).
A method of moving substrates into/out of process chambers comprising: rotating the crossed arms of a general X-shaped movable arm assembly in opposite directions about the X center; and moving two substrate holders in opposite directions as the arms move (i.e., the reverse-unison extension/retraction behavior).

Claim 17 — Method (opposed-unison, vertically stacked).
Providing a transport apparatus with a movable arm assembly having a reconfigurable general X-shaped section and two holders movable between extended and retracted positions; then moving the two holders in opposite unison between those positions, with the second holder traveling above the first holder. The "reconfigurable" language tracks the specification's admission that at the home position the arms align and the section "looses its general X-shape."

Claim 18 — Method (drive arms + coaxial shafts, same-side holders).
Moving the drive arms of a movable arm assembly in opposite directions of rotation about a center — expressly wherein that step is performed by rotating two coaxial drive shafts connected to the drive arms in opposite directions — and moving two substrate holders on the same side of the movable arm assembly in opposite directions as the drive arms move. The "same side" limitation captures the specification's emphasized advantage: both blades extend/retract along the same radial side, enabling a swap in one chamber without rotating about the shaft axis.

Dependent claims worth noting: Claim 5/12 (parallel paths, one directly above the other); Claim 6 (upper/lower arm sections on each proximal arm that pass beneath each other); Claim 11 (four proximal arm sections made from only three arm members); Claim 15 (opposite rotation of two coaxial shafts); Claims 16/19 (parallel, vertically offset paths).

5. CAFC / Litigation Check — 2026

Result: No authoritative record found tying US 5,647,724 to any Federal Circuit 2026 docket or to any pending PTAB proceeding.

• I searched for Federal Circuit 2026 docket activity and for "5,647,724" in litigation/PTAB contexts. No docket entry, appeal number, or IPR/PGR number referencing this patent surfaced.
• I did locate the patent's appearance in the cited-by and citation tables of later Brooks/Azenta and third-party patents (e.g., US 6,299,404, US 6,231,297, US 6,158,941, US 6,481,956, and Applied Materials' US 10,453,725 / US 10,943,805), i.e., it is heavily cited as prior art, but I found no live adversarial proceeding.

⚠️ Explicit uncertainty: Absence of search hits is not proof that no 2026 appeal, IPR, or district-court matter exists. My search tools did not return a complete or authoritative CAFC docket query for this patent, and the Federal Circuit docket system itself was not directly queryable here. For a definitive answer on 2026 dockets, a direct PACER/CM-ECF and USPTO PTAB (P-TACTS) docket query should be run against the patent number and against "Azenta" / "Brooks Automation" as party names. Also note the patent's statutory term already expired 2015-10-27, which makes new prospective-injunctive appeals unlikely, though past-damages claims within the § 286 six-year lookback window are a separate (and now largely time-barred) question.

6. Quick-Reference Card

US 5,647,724  |  App. 08/549,995  |  Filed 1995-10-27  |  Issued 1997-07-15
"Substrate transport apparatus with dual substrate holders"
Inventors: James C. Davis, Jr. / Christopher A. Hofmeister
Assignee of record: Brooks Automation, Inc. → (listed) Azenta Inc.
Status: Expired - Lifetime (term expired 2015-10-27)
Claims: 19 (independent 1, 8, 14, 17, 18)
Core concept: coaxially driven reconfigurable X-shaped linkage carrying two
              end effectors that move in reverse-unison, vertically offset,
              along the same side of the drive axis.
CAFC 2026: no records found (not a verified negative).

I'll research litigation involving US patent 5647724 across patent litigation sources.

Initial searches returned irrelevant results. Let me target patent litigation databases specifically.

No litigation hits yet. Let me search litigation-specific databases directly.

Litigation Search Results — U.S. Patent No. 5,647,724

Bottom line

I found no known litigation in which U.S. Patent No. 5,647,724 was asserted or challenged. My searches of patent-litigation-oriented sources (Unified Patents litigation materials, PACER-derived dockets, RPX/Justia/patent aggregators, and Brooks/Azenta SEC disclosures) did not return any case whose asserted patents include U.S. 5,647,724. Listed below are the relevant negative findings and the closest-adjacent cases that are not about this patent.

What I searched and what I found

Important non-matches (do NOT confuse with '724)

• JP 5647724 B2 — a different, unrelated Japanese patent (Fujikura K.K., "Wiring board and method for manufacturing same"). The number is numerically similar but is a distinct right and jurisdiction. Per your instruction, I'm treating identifiers literally and not conflating them.
• Brooks Automation US, LLC v. Planar Motor, Inc., No. 3:25-cv-00532 (D. Nev., filed Sept. 30, 2025) — a Brooks patent-infringement suit, but the asserted patents are U.S. '984 and '513 ("Multiple Dimension Position Sensor"), not the '724 patent.
• Asyst Technologies, Inc. v. Jenoptik AG (N.D. Cal.) — involved U.S. Pat. Nos. 4,974,166 and 5,097,421 concerning the IridNet transport system; Brooks was a potential but never-added defendant. Not the '724 patent.

Context on the patent itself

• U.S. 5,647,724 ("Substrate transport apparatus with dual substrate holders") issued July 15, 1997, filed Oct. 27, 1995; original assignee Brooks Automation Inc., current owner Azenta, Inc. (f/k/a Brooks Automation) per Google Patents/assignment records.
• Legal status is Expired – Lifetime (anticipated expiration Oct. 27, 2015), which materially limits the window for any infringement action (6-year damages lookback under §286 further limits recovery exposure).
• Note: the '724 patent is a family member of a large Brooks portfolio; related patents (e.g., U.S. 6,158,941; 6,231,297; 6,481,956) issued from continuations-in-part and could be the subject of separate enforcement activity — but you asked specifically about '724.

Confidence and limitations (stated explicitly)

• Low-to-moderate confidence that no litigation exists. I could not directly query PACER, Docket Navigator, or the full Unified Patents litigation portal (some sources returned only partial/embedded documents), so my search is not exhaustive. Litigation records remain the authoritative source.
• I found no evidence of any district-court action, ITC Section 337 investigation, PTAB proceeding (IPR/PGR/CBM), or CAFC appeal involving the '724 patent.

Recommended verification

To confirm definitively, query these directly (I could not access all of them fully):

1. Unified Patents litigation portal — https://portal.unifiedpatents.com/litigation (search "5647724")
2. PACER / CourtListener RECAP — nationwide docket search for "5,647,724" and "5647724"
3. USPTO PTAB (Patent Trial and Appeal Board) and USPTO PatentCenter "Litigation" tab for the patent
4. RPX Insight / Docket Alarm — patent-level litigation history

If you'd like, I can draft the exact query strings for PACER and CourtListener to run a nationwide assertion check, and cross-check the related Brooks continuations ('941, '297, '956) that were more likely enforcement vehicles.

I'll verify the structured-data block against the public record before writing.

Proceedings overview

Total AIA trial proceedings on US 5,647,724: 0. The USPTO Open Data Portal structured block for this patent returns no AIA trial proceedings, and targeted web searches surfaced no IPR, PGR, or CBM petition, no institution decision, no Final Written Decision, and no Federal Circuit appeal arising from a PTAB trial on this patent. There is therefore no breakdown by status — no active proceedings, no claims invalidated, no claims sustained, no settlements, no institution denials. Bottom-line defensive posture for a defendant: there is no PTAB record to work from — but you very likely don't need one, because the patent expired on 2015-10-27 and its entire remaining damages window has run out.

Two caveats on the "zero" finding, stated plainly:

• The absence is a verified negative only to the extent the USPTO ODP ingest and public web sources are complete. I could not find any pre-AIA inter partes reexamination either (those live at the Central Reexamination Unit, not the PTAB, and would not appear in an AIA-trials list), but I would not treat a search of that kind as exhaustive.
• Zero PTAB activity here is not the usual "no one bothered to challenge it" signal. IPR practice only opened on 2012-09-16; this patent had roughly three years of enforceable life left at that point. Its sibling/continuation patents in the same family — US 6,158,941, US 6,231,297, US 6,481,956, US 6,299,404 — also show no PTAB proceedings in the record I reviewed.

Per-proceeding detail

None exists. There is no proceeding number to report, and I will not manufacture one. Accordingly, no ### {PROCEEDING_NUMBER} sections, judge panels, petition grounds, institution decisions, FWDs, settlements, or appeals are provided — fabricating any of those would be the single worst failure mode in this task.

For completeness, the record for this patent shows only:

• Filing / grant: Application 08/549,995 filed 1995-10-27; US 5,647,724 granted 1997-07-15.
• Terminal status: "Expired - Lifetime"; anticipated expiration 2015-10-27.
• Assignment chain: Brooks Automation, Inc. (original assignee, assignment recorded 1996-01-18) → Morgan Stanley Senior Funding security interest (2017-10-06) → released 2022-02-01, with current assignee listed as Azenta, Inc. (f/k/a Brooks Automation, Inc.).

Strategic summary

Claim status: all 19 claims are UNTESTED at the PTAB. Claims 1–19 were never challenged in an AIA trial, so nothing has been canceled and nothing has been confirmed. There is no narrowing to report and no "surviving claims" list to give — the full claim set stands as issued, unadjudicated. That is a different proposition from "hardened." An untested patent is not a validated patent; it simply has no adverse administrative history. Independent claims 1 (X-shaped section + two holders), 8 (four proximal arm sections at four heights on a coaxial drive), 14 and 17 (method claims for opposite-direction/opposite-unison holder movement), and 18 (same-side holder movement with counter-rotating coaxial shafts) are all untouched.

Estoppel landscape: none attaches. Because no IPR or PGR was instituted to a Final Written Decision, 35 U.S.C. § 315(e)(2) estops no one. There is no petitioner, no real party in interest, and no privy carrying an estoppel burden into a district court or ITC case. Every prior-art ground a defendant could raise — including grounds that would have been "reasonably could have raised" in a hypothetical IPR — remains fully available. Conversely, there is no earlier petitioner's win you can borrow and no FWD you can cite for preclusive effect.

Pattern signals: essentially absent. No serial petitioner, no repeat filings, no patent-owner appeal practice at the Federal Circuit, and no defensive aggregator (Unified Patents or similar) in the chain for this patent. The family shows the ordinary Brooks/Azenta prosecution-and-maintenance pattern continued through the continuation patents above; the commercialization-side lawsuit activity I could find (e.g., Brooks Automation US, LLC v. Planar Motor, Inc., No. 3:25-cv-00532 (D. Nev., filed 2025-08-30)) does not, on the record I reviewed, assert this patent.

Recommended next steps

1. Lead with expiration, not with invalidity. US 5,647,724 expired 2015-10-27. Any infringement theory requires acts occurring on or before that date. Under 28 U.S.C. § 286, a patentee may recover damages only for infringement occurring within six years before the complaint is filed — which means the last actionable filing date for this patent was on or about 2021-10-27. If you receive a demand letter today (2026-09-30) citing this patent, the damages claim is facially time-barred; the correct response is a § 286 / expiration defense, not an IPR.
2. If you nonetheless need a validity challenge (e.g., for a declaratory-judgment posture, a licensing indemnity dispute, or because the demand letter also cites the continuations US 6,158,941 / 6,231,297 / 6,481,956 / 6,299,404, which have different expiration dates), note that no § 315(e) estoppel blocks you. You are free to run art against claims 1–19 on the full field. Start with the references already in the record: US 5,180,276 and US 4,901,601 appear in the patent's own prior-art discussion, and US 5,270,600 is incorporated by reference for the coaxial drive. Note also that the patent's own prosecution record cites JPH0430552 and the cited-by art reflects a large, crowded field of two-arm/dual-holder transfer robots from the 1990s.
3. Verify before relying on the negative. Confirm the zero-PTAB finding directly at PTAB E2E and the USPTO PTAB Decisions database by patent number, and check PatentCenter for the application's full file history (including any reexamination request that would not appear in an AIA-trials listing). Run a parallel CourtListener docket search for the patent number to confirm no district court or Federal Circuit activity I did not find.
4. Do not over-claim the negative in a brief. The accurate statement is: "No IPR, PGR, or CBM proceeding has ever been instituted against US 5,647,724, and no claim has ever been canceled by the PTAB; the patent's full claim set is unadjudicated." Saying "the patent has survived IPRs" would be false — there were none to survive.

This is an analysis of public records as of 2026-09-30 and is not legal advice; confirm the statutory-bar and expiration points with counsel against the specific filing date and asserted-acts record.

I'll work from the authoritative patent text provided and verify ownership details with targeted searches.

Let me verify the assignment records and check for any assertion activity.

Let me dig deeper on the post-2022 ownership question and any assertion of this patent.

Assignment & Ownership Analysis — US 5,647,724

Patent: US 5,647,724 — Substrate transport apparatus with dual substrate holders
App. No. 08/549,995 · Filed 1995-10-27 · Issued 1997-07-15 · Anticipated expiration 2015-10-27
Source of record: Google Patents US5647724A legal-events extract (reproduced in the full patent text supplied) · Verification: USPTO Assignment Center (search by patent number)

Data-availability caveat, stated up front: the Google Patents legal-events extract supplied to me exposes date, conveyance code, assignor, assignee and reel/frame — but not the correspondent-of-record field. I therefore do not name any recording attorney or firm; doing so would be fabrication. Correspondent capture requires pulling the Assignment Abstract of Title from Assignment Center (see "Verification gaps" at the end of the timeline section).

Inventors

Departure pattern — not present, and one inventor affirmatively stayed. Hofmeister appears as a named inventor on a later Brooks Automation, Inc. PCT application (PCT/US2007/012582, filed 2007-05-24, published as WO2007139981, applicant Brooks Automation, Inc., listed at Hampstead, NH) — i.e., he was still filing Brooks cases roughly 11 years after this filing. There is no evidence of either inventor departing within 12 months, and no subsequent portfolio divestiture that a departure would presage. Davis' tenure is not determinable from the records available to me — I flag that as a gap rather than infer it.

Original assignee

Brooks Automation, Inc., Chelmsford, Massachusetts (Massachusetts corporation; assignment recorded at reel 007770/0234).

• Line of business: semiconductor manufacturing automation — vacuum wafer-transfer robotics, integrated automation systems, contamination control. In its own SEC language, Brooks was "a leading automation provider and partner to the global semiconductor manufacturing industry" since its founding in 1978 (Azenta, Inc. Form 10-Q for the quarter ended 2023-03-31).
• Did it ship a product embodying the claims? Yes — the claims (a dual-holder X-shaped substrate transport with coaxial drive shafts, claims 1, 8, 14, 17, 18) read on Brooks' core vacuum transfer-robot product line, which was the company's flagship business from the 1980s onward. This was not a paper patent held by a non-practicing entity.
• Current status of the original assignee: Operating; name changed; business carved out. Brooks Automation, Inc. renamed itself Azenta, Inc. (Nasdaq: AZTA) effective 2021-12-01, then closed the sale of its entire Semiconductor Solutions Group to Thomas H. Lee Partners, L.P. ("THL") for $3.0 billion cash on 2022-02-01. Azenta continues as a public life-sciences company. The semiconductor business continues to trade as Brooks Automation under THL ownership (cf. Brooks Automation US, LLC v. Planar Motor, Inc., D. Nev. 3:25-cv-00532, filed 2025-09-30). No bankruptcy, no Chapter 7/11, no dissolution is evidenced for either entity.

Assignment timeline

Three records appear in the legal-events chain. Only one is a conveyance of ownership; the other two are a security interest and its release. That distinction matters and is carried into the NPE analysis below.

1. 1996-01-09 (executed) / recorded 1996-01-18 — Reel 007770/0234

   • Conveyance: Assignment of assignors' interest
   • Assignor: James C. Davis, Jr.; Christopher A. Hofmeister (joint inventors)
   • Assignee: Brooks Automation, Inc. (Massachusetts)
   • Correspondent: not exposed in the available record set. (Single appearance at most; no recurrence can be assessed.)
   • Context: Original employment/obligation assignment to the operating company — the founding record of title.

2. 2017-10-04 (effective) / recorded 2017-10-06 — Reel 044142/0258

   • Conveyance: Security interest (grant of collateral)
   • Assignors (grantors): Brooks Automation, Inc.; BioStorage Technologies, Inc.
   • Assignee (secured party): Morgan Stanley Senior Funding, Inc. (Maryland)
   • Correspondent: not exposed in the available record set.
   • Context: Securitization — a blanket IP collateral grant securing a corporate credit facility. This is not an ownership transfer. Note that Morgan Stanley Senior Funding, Inc. appears as collateral agent on large numbers of unrelated security-interest recordings (e.g., the Twitter/X trademark assignments at reels 7879/0918, 8474/0691, 8849/0512), which is consistent with routine collateral-agent practice and not with an NPE holding patents.

3. 2022-02-01 (effective) / recorded 2025-11-04 — Reel 073514/0609

   • Conveyance: Release of security interest recorded at reel/frame 044142/0258
   • Assignor (releasing party): Morgan Stanley Senior Funding, Inc.
   • Assignees (released parties): Azenta, Inc. (f/k/a Brooks Automation, Inc.); Azenta US, Inc. (f/k/a Brooks Life Sciences, Inc., f/k/a BioStorage Technologies, Inc.)
   • Correspondent: not exposed in the available record set.
   • Context: Extinguishment of the 2017 lien. The 2022-02-01 effective date is not incidental — it is the exact closing date of the THL carve-out, and Azenta's 10-Q confirms it "used approximately $50 million of the proceeds from the sale to extinguish the outstanding balance of its term loan facility" and terminated its revolver. Collateral release at close of a divestiture; again not an ownership transfer.

No other ownership assignment is recorded in the chain visible to me. In particular, I do not see a recorded assignment of this patent to a THL-affiliated semiconductor entity (e.g., Brooks Automation US, LLC). Google Patents' derived "current assignee" field still reads Azenta Inc, which is the name-change successor of the original assignee.

Verification gaps — what to pull next:

• Correspondent-of-record for reels 007770/0234, 044142/0258, 073514/0609 (Assignment Abstract of Title). No correspondent appears in the extract I have, so no repeat-correspondent finding is possible here.
• Whether the 2022 carve-out included a separate assignment of this patent (and its family) to the THL semiconductor entity. If such an assignment exists, it was not in the events list supplied. The patent's 20-year term ended 2015-10-27, so this is a title-cleanness question, not an assertion question.

Timeline diagram

timeline
    title Ownership record of US 5647724
    1995 : Filed by Brooks Automation
    1996 : Inventors assign to Brooks
         : Reel 007770 frame 0234
    1997 : Patent issued
    2015 : Patent reaches end of term
    2017 : Security interest granted
         : Reel 044142 frame 0258
    2021 : Brooks Automation renamed Azenta
    2022 : Semiconductor unit sold to THL
         : Security interest released
    2025 : Release recorded
         : Reel 073514 frame 0609

NPE / troll-pattern signals

Threshold fact that dominates every signal below: the patent expired 2015-10-27 (anticipated expiration per the record; maintenance fees paid through year 12 on 2009-01-15, legal status "Expired - Lifetime"). An expired patent has no assertion value. Any NPE-pattern reading would have to explain an assertion of a patent that has been dead for a decade — none is in evidence.

1. Shell-entity transfer — NOT PRESENT. There is no recorded transfer to any licensing entity. The only ownership transfer in the entire chain is the 1996 inventors-to-Brooks assignment (reel 007770/0234). The record owner remains Azenta, Inc. (f/k/a Brooks Automation, Inc.), a Nasdaq-listed operating company. No "IP / Holdings / Ventures / Licensing" entity appears anywhere.

2. Known asserter in the chain — NOT PRESENT. None of the parties on the standard NPE rosters (Acacia, Marathon, IV, IPNav, Wi-LAN, Mosaid/Conversant, Vringo, Pendrell, Innovatio, MPHJ, Lumen View, Round Rock, Erich Spangenberg entities) appears as assignor or assignee. Morgan Stanley Senior Funding, Inc. is a bank acting as collateral agent (reel 044142/0258) — a lending role, not an assertion role.

3. Repeat correspondent across the chain — UNCLEAR / NOT ASSESSABLE. The correspondent field is absent from the legal-events data available to me, so recurrence cannot be tested. I make no finding. This signal should be re-run against the Assignment Center abstract of title for all three reels before being scored either way.

4. Cascading transfers — NOT PRESENT. One ownership conveyance in ~28 years of recorded history. The two post-issuance records are a lien (2017) and its release (2022/recorded 2025) referencing the same reel/frame — a single credit facility, not chained shell transfers. No LLC-to-LLC cascade, no shared registered-agent address, no common principals.

5. Pre-litigation transfer — NOT PRESENT. No infringement action naming US 5,647,724 was located. The nearest 2025 activity is Brooks Automation US, LLC v. Planar Motor, Inc. (D. Nev. 3:25-cv-00532, filed 2025-09-30), but I have no evidence that US 5,647,724 is asserted there — and given the 2015 expiry it cannot be. Stated as a gap, not a finding.

6. Bankruptcy fire-sale — NOT PRESENT. No Chapter 7/11 proceeding for Brooks Automation, Inc. or Azenta, Inc. is evidenced. The 2022 transaction was a $3.0B all-cash solvent carve-out to a private-equity sponsor, the opposite of a distressed sale.

7. Privateering — NOT PRESENT on the record. Azenta sold the entire operating Semiconductor Solutions Group business to THL, retaining no assertion role, and the patent lay on Azenta's side of the transaction. A carve-out of a whole business unit is not the operating-company-to-NPE pass-through that privateering describes. If the semiconductor patents did move to the THL entity, that entity is a product-shipping operating company (it is currently suing a competitor over its own robotics portfolio), not an NPE.

8. Defensive aggregator (anti-NPE) — NOT PRESENT. The chain does not terminate at RPX, AST, LOT Network, Unified Patents, or OIN. No defensive-aggregation record exists.

Verdict

Defensive / non-asserting — with one explicit qualification: the chain does not terminate at a defensive aggregator, so I am invoking this category for its non-asserting limb, not its stated rationale. If the taxonomy must be read strictly, this matter is best treated as "no NPE pattern; expired operating-company patent," which is not a bucket the five options cleanly provide.

Justification. The recorded ownership chain shows exactly one conveyance of title — inventors to Brooks Automation, Inc. at reel 007770/0234 (executed 1996-01-09) — after which title never left the operating company, continuing through the 2021-12-01 name change to Azenta, Inc. The only two later records are a bank collateral grant at reel 044142/0258 (effective 2017-10-04) and its release at reel 073514/0609 (effective 2022-02-01, the exact closing date of the $3.0B THL Semiconductor Solutions carve-out) — encumbrances, not transfers, and neither involves an NPE. The patent reached the end of its 20-year term on 2015-10-27 with all maintenance fees paid, so it carries no assertion value; there is no shell entity, no known asserter, no cascade, and no adversary proceeding to support any NPE classification.

Verify at: Assignment Center — search "5647724" · Google Patents US5647724A · USPTO Patent Center

Action items to close the two open gaps: (a) retrieve correspondent-of-record for reels 007770/0234, 044142/0258, 073514/0609 to complete signal #3; (b) confirm whether the 2022 carve-out included a separate recorded assignment of the 08/549,995 family to the THL semiconductor entity — which would explain the 2025 recording lag and the divergence between the record owner (Azenta, Inc.) and the operating semiconductor business (Brooks Automation US, LLC).

I'll search for authoritative records on US 5,647,724 and each of its cited references, starting with the patent itself.

Let me verify the key cited references individually, focusing on those most relevant to the X-arm linkage and coaxial drive architecture.

Prior-Art Analysis — US 5,647,724 ("Substrate transport apparatus with dual substrate holders")

Note on dates: The task header says "Current Date: April 26, 2026," while my operating environment reports today as 2026-09-30. I flag this inconsistency rather than silently picking one; it does not affect the substantive analysis below, which rests on the patent's 1995-10-27 filing/priority date.

Note on method / limitation: I confirmed the document via Google Patents and Justia for US 5,647,724 / application 08/549,995 (filed 1995-10-27, issued 1997-07-15, Brooks Automation Inc., inventors Davis & Hofmeister). I was not able to complete an individual full-text verification of every one of the 23 cited references (my tool budget was exhausted mid-research). Descriptions below are drawn from (a) the patent's own citation table, (b) the specification's characterizations, and (c) search results I did retrieve for the key references. Where I am inferring rather than quoting a verified source, I say so. This is a provisional § 102 screen, not a validity opinion.

1. What was searched

• Target document located and confirmed on Google Patents (patents.google.com/patent/US5647724A/en) and Justia (patents.justia.com/patent/5647724).
• The prior-art universe for this task = the 23 references listed in the "Patent Citations (23)" table of US 5,647,724 (all marked as cited by the examiner), plus the references described in the specification's Background section and the two documents expressly incorporated by reference.

Critically, the examiner's citation set is dominated by generic linkage/hoist/wafer-handling art and pre-1992 frog-leg transfer arms. Only a handful are close enough to the claimed reconfigurable-X/dual-holder concept to be genuine § 102 candidates.

2. Master table — all 23 cited references

Dates are as printed in the '724 citation table (the first column is labeled "priority date" by Google Patents and does not always equal the actual filing date). For US 4,909,701, Unified Patents lists the application date as 1987-05-17 and priority as 1983-02-13; I report the Google table figure above and note the discrepancy rather than harmonizing it.

3. The genuinely relevant references (element-by-element § 102 screen)

A. US 5,180,276 — Hendrickson, Brooks Automation. Highest relevance.

• Citation: US 5,180,276 A; filed 1991-04-18; issued 1993-01-19; App. 687,288; "Articulated arm transfer device."
• Disclosure (verified): A rhomboidal link structure of two pairs of forearms pivotally joined at the elbows and wrists; each wrist supports a holding structure; the elbows are driven in mirror-image semicircular paths by a pair of upper arms; the motion is arranged so that "at any time one holding structure is moving rapidly between an extended position and a park position while the other holding structure is slowly traveling … between a park position and a retracted position." Claim 1 recites driving the first upper arm "through an angle in the range of from greater than 120° up to and including 180° to move said first holding means between a first extended position and a first retracted position while simultaneously moving said second holding means between a second retracted position and a second extended position."
• Why it is the closest art: it is the only examiner-cited reference that shows two substrate holders moving in opposite/reciprocal fashion from a common articulated arm assembly, and the '724 specification itself lists it as the "two substrate holders" prior art.
• Potential § 102 targets:
  • Claim 14 (method: moving crossed arms of a general X-shaped movable arm assembly in opposite directions of rotation; moving two substrate holders in opposite directions). The '276 upper arms counter-rotate and its two holders move oppositely — a strong § 102 argument, except that the '276 upper arms rotate about two adjacent shoulder pivots, not about "a center of the general X-shape" as claim 14 requires. That gap is the key distinction to attack.
  • Claim 17 (two holders in opposite unison, one above the other). The '276 holders are on separate pairs of forearms; whether they are vertically stacked (one above the other) is the potentially missing limitation — I could not confirm vertical offset from the retrieved text.
  • Claim 1 — weaker: claim 1 requires proximal arms "rotatably connected to each other at a center of the X-shaped section," whereas '276 mounts them on separate shoulder pivots.
• Confidence: Moderate that it is the best § 102/§ 103 reference; low that it fully anticipates claims 1/14/17 as written, because of the "center of the X" and vertical-offset limitations.

B. US 4,909,701 (Brooks/Hardegen) and US 4,666,366 (Canon/Davis) — frog-leg linkage core

• Citations: US 4,909,701 A, priority 1983-02-14, issued 1990-03-20; US 4,666,366 A, priority 1983-02-14, issued 1987-05-19.
• Disclosure (verified for both): two articulated arms whose drive segments carry gears; the drive segments are rotated in opposite directions, causing the arms to extend/retract in a "froglike" motion; a platform/end effector is coupled to the driven segments via anti-rotation gears to keep the platform orientation constant.
• Relevance: these teach the opposed-rotation, constant-orientation articulated linkage that underlies claim 14 and the claim 2/3 "distal arms / intermeshed gear" structure. Both are single-platform devices, so they cannot anticipate the "two substrate holders" limitations of claims 1, 14, or 17. They are, however, strong § 103 combination art against the linkage sub-elements of claims 1–4 and 14.
• Note: US 4,666,366 names James C. Davis — the same inventor as the '724 patent — which is relevant to any § 102(b)/derivation or double-patenting discussion.

C. US 5,270,600 — Koyo Seiko. Expressly incorporated by reference.

• Citation: US 5,270,600 A; priority 1991-05-08; issued 1993-12-14; "Magnetic drive device."
• Relevance: the '724 specification states "One such coaxial drive shaft assembly is disclosed in U.S. Pat. No. 5,270,600 which is hereby incorporated by reference in its entirety." Because it supplies the two-shaft coaxial drive of claims 8/15, any analysis of claims 8 and 15 must treat its disclosure as part of the '724 specification. It does not itself disclose the four-proximal-arm-section, four-height mounting of claim 8.
• Potential § 102 targets: supports obviousness/§ 112 analysis of claims 8 and 15; unlikely to anticipate on its own.

D. US 5,441,409 and EP 0 423 608 A1 — Applied Materials (magnetically coupled multi-blade robots)

• Citations: US 5,441,409 A, priority 1989-10-20, issued 1995-09-05, "Robot assembly"; EP 0 423 608 A1, priority 1989-10-20, published 1991-04-24, "Two-axis magnetically coupled robot."
• Relevance: these are concentric-shaft, magnetically coupled, dual-arm/dual-blade transport robots for vacuum chambers — i.e., close to the claim 8 "coaxial drive shaft assembly … four proximal arm sections at different heights" concept and the claim 18 "same-side, coaxial-shaft" method. The '724 specification acknowledges the general class (it also cites US 4,951,601 as requiring rotary seals).
• Potential § 102 targets: claims 8 and 18 most plausibly; claim 1 only if the disclosure shows a two-holder X-section, which I did not verify.
• Caveat: I retrieved only the bibliographic/abstract-level record for these; a full-text review is required before asserting anticipation.

E. US 4,951,601 — Applied Materials

• Citation: US 4,951,601 A; priority 1986-12-19; issued 1990-08-28; "Multi-chamber integrated process system."
• Relevance: cited in the '724 Background as "a substrate processing apparatus with multiple processing chambers and a substrate transport apparatus." It supplies the environment/preamble of method claims 14, 17, 18 (transporting substrates into and out of processing chambers in a substrate processing apparatus) but not the X-shaped dual-holder linkage.
• Potential § 102 targets: none of the independent claims on its own; relevant to preamble scope only.

F. Remaining transfer/handling references (US 5,333,986; US 5,151,008; JP H04-30552; JP H02-292153; US 4,730,975; US 4,907,467)

• All predate 1995-10-27 and describe variously: substrate transfer apparatus (Tokyo Electron, Matsushita), plate-article conveyors (Tokyo Electron Sagami, Fuji Electric), and articulated industrial robot arms (Toshiba, Fanuc).
• Assessment: these are § 102(b)/§ 103 background art supporting the general state of substrate-transfer robotics. None of the retrieved records shows a reconfigurable X-shaped section with two holders on different end-pairs, so I would not assert these as anticipatory without full-text review. They are more naturally cited for the "articulated horizontal arm" concept in claim 1.

G. The purely mechanical / unrelated set (items 12–21, 17–21 above)

US 3,874,525 (IBM workpiece handling), US 3,823,836 (vacuum sheet handling), US 4,208,159 (plasma wafer treatment), US 4,062,463 (cassette load mechanism), US 3,730,595 (air-slide indexer), US 4,101,970 (motor with frequency generator), US 1,190,215 (linkage), US 2,282,608 (hoist), US 3,768,714 (microfilm printer), US 4,721,971 (photo logging).

• Assessment: these are examiner working-file art establishing that wafer handling, vacuum chucks, gearing and linkages were known. They do not disclose the claimed combination and should be treated as non-anticipatory. The presence of US 1,190,215 (a 1916 linkage) and US 2,282,608 (a 1942 hoist) in the citation list is characteristic of a mechanical-linkage examiner building a general-knowledge record rather than citing close art.

4. Bottom-line rankings

Key structural point: the '724 independent claims hang on two limitations that the cited art does not obviously show together — (i) the "general X-shaped section whose proximal arms are rotatably connected at a center" (claims 1, 14, 17), and (ii) the four proximal arm sections at four different heights, with the 1st/3rd on the inner shaft and 2nd/4th on the outer shaft (claims 8, 11, 13). US 5,180,276 comes closest to the first but uses separate shoulder pivots; the Applied Materials dual-blade art comes closest to the second but I did not verify the four-height/three-arm-member structure.

5. Explicit uncertainties and required verification

1. Incomplete full-text review. I verified the disclosures of US 5,180,276, US 4,909,701, US 4,666,366, US 5,270,600 and US 4,951,601 from retrieved text; for the remainder (especially the Applied Materials US 5,441,409 / EP 0 423 608 pair and the two Japanese references) I relied on bibliographic/abstract data. All § 102 conclusions above are provisional.
2. Anticipation vs. obviousness. As drafted, none of the cited references appears to disclose every limitation of independent claims 1, 8, 14, 17 or 18 in a single document; the realistic challenge is § 103 (e.g., US 5,180,276 + US 5,270,600), not § 102. I have therefore labeled the table "potential § 102 targets" rather than confirmed anticipations.
3. Cross-reference discrepancy to flag: the previously generated summary describes claim 14 as moving holders "in opposite directions relative to the center of the general X-shape." The authoritative granted text of claim 14 says only "moving two substrate holders in opposite directions as the arms are moved"; the "relative to the center of the general X-shape" phrase appears in claim 18. This is a minor transcription drift in the earlier section and should be corrected.
4. Foreign counterparts exist (WO 1997015423 A1; EP 0862510 A1/A4, withdrawn; JP 4063323 B2; KR 100482295 B1; TW 401370 B; AU 7517596 A, abandoned). If a full prior-art/validity study is needed, the international search reports for the WO/EP counterparts will supply examiner-cited art beyond the 23 U.S.-record citations listed here.
5. Incorporated-by-reference document not identified by number: the specification also incorporates US application 08/421,533, "Articulated Arm Transfer Device" (S-band joint constraint). I did not confirm which granted patent, if any, that application issued as, and I am not guessing its number.

If you want, I can next run a focused full-text review of US 5,180,276 and the Applied Materials US 5,441,409 / EP 0 423 608 pair to convert the provisional claims-1/8/14/17/18 screening into a definitive per-limitation anticipation chart.

I'll ground the obviousness analysis by first verifying what the key cited references actually disclose, since the citation tables give me only titles/dates.

Let me verify two more cited references to complete the element mapping.

Obviousness Analysis — U.S. 5,647,724 under 35 U.S.C. § 103

Analyst note on scope and limits. I used the prior art identified on this patent's own page: the three references named in the specification's "Prior Art" section (US 4,951,601; US 5,180,276; US 5,270,600), the two incorporated-by-reference documents (US 5,270,600 and application 08/421,533), and the examiner-cited "Citations (23)" table. I verified the disclosure of the most load-bearing references (US 4,909,701; US 4,666,366; US 5,180,276; US 5,447,409; US 5,151,008) against their published text/claims. I could not verify US 5,333,986 (Tokyo Electron, "Transfer apparatus"), the Japanese-language citations (JPH02292153, JPH0430552, JPH06132380, JPH07227777, JPH03212950/H04186860), or US 1,190,215 beyond its title/class, so I do not build a primary combination on them. Treat column-and-line pinpoint cites below as requiring confirmation against the full reference texts. Nothing here is a legal opinion or a substitute for the prosecution record (file wrapper) of the '724 patent, which I did not review.

1. Claim construction points that drive the analysis

Two constructions matter:

• "general X-shaped section." The specification concedes the section "looses its general X-shape" at the home position and is so named "for lack of a better descriptive term." Functionally, the limitation is a crossed/hinged two-arm linkage whose arms are relatively rotatable about a central (drive) axis, i.e., a reconfigurable frog-leg/scissor geometry. That reading makes the claim highly vulnerable to art showing two arms pivotally coupled at a center.
• "each holder connected to a different pair of ends." This is satisfied by any linkage carrying two end effectors on two distinct articulations of the same central arm assembly.

Claims 8/14/17/18 are narrower because they recite the coaxial two-shaft drive, the four-height arm-section stack, and the same-side, vertically-offset, opposite-unison motion. Each of those features is separately taught or suggested, as shown below.

2. The prior-art arsenal (what each reference supplies)

3. Claim 1 — the broad apparatus claim

Proposed combination: US 5,180,276 in view of US 4,909,701 (optionally + US 4,666,366).

• US 5,180,276 supplies everything except the literal "X-shaped section," and it supplies the two core elements: (a) two proximal arms (the upper arms) that are coupled at a center by a drive linkage and driven in counter-rotation so their free ends sweep mirror-image arcs, and (b) two substrate holders, each on a different one of two holder/forearm pairs.
• US 4,909,701 (same assignee) supplies the exact center-pivot crossed-arm structure: two arms whose proximal drive segments meet at a common central gear mesh and whose distal ends carry pinned, orientation-constrained elements — i.e., a reconfigurable X when the arms are relatively rotated. It also supplies the anti-rotation gears that keep a holder pointing outward.
• Substituting '701's center-pivoted crossed arms for '276's upper-arm/rhomboid linkage to reach a single compact "X-shaped" central section is a mere rearrangement of parts producing the same known extend/retract function.

Result: claim 1 is prima facie obvious. The only arguable distinction is nomenclature ("X-shaped"), which the specification itself treats as descriptive only.

4. Claim 8 — the coaxial-drive apparatus claim

Proposed combination: US 5,447,409 and/or US 4,951,601, further in view of US 5,270,600 and US 5,151,008.

Element mapping:

• Coaxial drive shaft assembly; first shaft and second shaft → US 5,270,600 (incorporated into '724), US 4,951,601 (concentric-shaft drive), and US 5,447,409 ("two independent arms coaxially rotatable about a fixed axis").
• Four proximal arm sections, each extending at a different height → US 5,151,008 (two links plus two opposing links at vertically offset tiers; holders at different heights on the J-frame) combined with US 5,180,276's "superimposed alternately" upper arms.
• First and third sections fixed to the first shaft; second and fourth to the second shaft → US 5,447,409 (each coaxial arm drives a distinct pair of struts/carriers) and US 5,151,008 (each shaft 43 drives its own link 42).

Motivation: '409 expressly states that the opposed-rotation drive extends one carrier while retracting the other, and cites throughput. Splitting each arm into an upper and lower section mounted to alternate shafts is precisely how the art stacks multiple articulations on a two-shaft coaxial column.

Claim 8 is prima facie obvious over this combination. Limitation to note: claim 8 says only "substrate holders" (not expressly two), so it is broader still.

5. Method claims 14, 17, 18

• Claim 14 (crossed arms rotated in opposite directions about an X center; two holders moved in opposite directions): US 5,180,276 (counter-rotating drive arms; one holder extends while the other retracts) + US 4,909,701 (opposite rotation of the geared drive segments produces extension/retraction) + US 5,151,008 (gear pair 70/72 rotating links in opposite directions). Obvious.
• Claim 17 (reconfigurable X section; two holders between extended/retracted; opposite unison; second holder above the first): US 5,180,276 (opposite-unison dual holders) + US 5,151,008 — which expressly discloses holders that "pass each other above and below" while traveling in the extended/retracted directions. This is close to a direct read on the claim; the "reconfigurable" X adds nothing beyond a movable crossed linkage ('701).
• Claim 18 (drive arms rotated oppositely via two coaxial shafts; two holders on the same side moved in opposite directions): US 5,447,409 (coaxial arms counter-rotated to extend one carrier while retracting the other) + US 5,151,008 (paired links translating holders in opposite directions on a single side of a transfer chamber). The specification's own asserted advantage — swapping a wafer in one chamber without rotating the holders about the shaft axis — is exactly the throughput benefit the art already sought (see '276's and '409's stated objectives).

6. Dependent claims

7. Motivation to combine (KSR factors)

1. Same field, same problem. All primary references are wafer/substrate transfer robots for multi-chamber (cluster) tools. Avoidance-of-collision, small retracted envelope, and throughput are the stated problems in every one.
2. Explicit recognition of the problem and the solution direction. US 5,180,276 states the prior single-platform arm "limits through-put," and US 5,447,409 touts "increased throughput" from storing one wafer while placing another. This defeats a "long-felt but unsolved need" narrative: the need was identified and dual-blade solutions were already in the art years before 1995.
3. Predictable results. Adding a second holder to the second pair of ends of an existing crossed-arm linkage, and driving both by counter-rotating coaxial shafts, is the combination of known elements each performing its known function (extension/retraction, opposed-rotation extension) with no unexpected result.
4. Identity of inventive entity/assignee and cross-citation. US 4,666,366, US 4,909,701, US 5,180,276 and the '724 patent share a common assignee (Brooks Automation), and the references cite one another — a strong KSR "design incentive" and "common ownership" factor. US 4,951,601 and US 5,447,409 share Applied Materials.
5. Applicant's own incorporation by reference. US 5,270,600 and application 08/421,533 are expressly incorporated into '724, evidencing that the applicant considered these references combinable with the base arm architecture.
6. Applicant's own admissions in the specification. (a) US 5,180,276 already "discloses a substrate transport apparatus with two substrate holders"; (b) "X-shaped" is used "for lack of a better descriptive term"; (c) orientation retention can be "any suitable type of system." These admissions narrow the gap the claims can legitimately occupy.

8. Counterarguments and weaknesses in the § 103 case (stated candidly)

• No single verified reference shows the exact "X-shaped section with holders on different pairs of its ends." The primary combination therefore rests on modification of US 5,180,276's rhomboid/upper-arm geometry with US 4,909,701's center-pivoted crossed arms. A patentee could argue this is impermissible hindsight-driven redesign rather than an art-suggested substitution. The response is that both are Brooks frog-leg devices solving the same problem, making the substitution predictable.
• Same-side versus opposite-side holders. US 5,447,409 places carriers 180° apart, and US 5,180,276's holders move along a shared center line in opposing directions (not same-side parallel paths). Claim 18's "same side" limitation is best met by US 5,151,008; if one declines to treat '008 as combinable (different linkage type — parallel-link rather than frog-leg), claim 18's obviousness becomes contestable. Claim 17's "above the first holder" limitation likewise depends materially on '008.
• Claim 11 (three members → four sections) is a structural economy with no clear art teaching; it should be expected to survive as a dependent claim unless a parts-consolidation reference is added.
• Secondary considerations not adjudicated here. Brooks/Azenta commercial success in dual-blade vacuum robots, copying, and industry praise could be advanced, but would require proof of nexus to these claims; given the crowded art and the pre-existing recognition of the throughput problem, a nexus argument looks difficult.
• Procedure. The examiner allowed the '724 claims with these references of record, so any invalidity theory is a de novo combination that would have to be established on the full texts (including the Japanese references I could not verify), not merely on the citation tables.

9. Bottom line

Using only the prior art on this patent's own face, every independent claim is vulnerable under § 103:

• Claim 1 — obvious over US 5,180,276 + US 4,909,701 (optionally + US 4,666,366).
• Claim 8 — obvious over US 5,447,409 and/or US 4,951,601 in view of US 5,270,600 and US 5,151,008.
• Claim 14 — obvious over US 5,180,276 + US 4,909,701 + US 5,151,008.
• Claim 17 — obvious over US 5,180,276 + US 5,151,008.
• Claim 18 — obvious over US 5,447,409 + US 5,151,008 (with '276).

The strongest, best-documented combination is the dual-holder frog-leg pair US 5,180,276 / US 5,447,409 supplying the two-holder and opposed-coaxial-drive teachings, plus US 4,909,701 for the center-pivoted crossed-arm structure and US 5,151,008 for vertically offset, opposite-direction parallel holder paths. The weakest links in the case are claim 11 and the "same-side" limitation of claim 18, which deserve the closest scrutiny against the fuller texts of US 5,333,986 and the Japanese-language citations that I could not verify.