US 4044126

I'll verify against live sources before summarizing.

Summary — US 4,044,126

Sources checked: Google Patents (https://patents.google.com/patent/[US4044126A](/patent/US4044126A)/en), Justia/company-profile listings, and reference citations in later patents (e.g. WO 2013037482, EP0172672A1). Live search returned no results for a "4044126" CAFC 2026 docket — see the litigation note at the end.

Bibliographic data

Abstract (as issued)

"An antiinflammatory steroid exhibiting a tendency to crystal growth in suspension in aerosol propellants is contacted with a halogenated hydrocarbon to form a crystalline solvate, which, after removal of some or all of the propellant from the crystals, is reduced to a particle size permitting inhalation into the human bronchial system when dispersed as an aerosol, the micronized crystalline solvate not thereafter exhibiting crystal growth in the aerosol propellant. The solvate is a new composition of matter which has been characterized by I.R. spectra and the aerosol formulation prepared therefrom has valuable therapeutic properties, particularly in the treatment of asthma."

The problem the patent solves

Micronized beclomethasone dipropionate (2–5 µm, inhalable) filled into a propellant 11/12 aerosol can grows crystals >20 µm that cannot pass the trachea. The inventors discovered the growing crystals were not pure drug but a propellant-11 solvate of the steroid. Once that new crystalline form is made deliberately, micronized and resuspended, no further crystal growth occurs — making the solvate, counterintuitively, the better inhalation ingredient.

Plain-language overview of independent claim 1

There is exactly one independent claim, and it is a process/method claim, not a composition claim (the compositions were moved to the division, US 4,414,209).

Claim 1 — a three-step "convert and size-reduce" method:

1. Start material: an anti-inflammatory steroid of a broadly but precisely defined class — pregn-4-en-3,20-diones (the prednisolone/prednisone family of corticosteroids). The claim then layers on structural limitations:
   • 17α-position: hydroxy or acyloxy (but if 17α is hydroxy, then 21 must be acyloxy), or a 16,17-ketonide;
   • 11-position: an "axo" group (the text as published/fetched reads "axo," which appears to be a typographical or OCR artifact for "oxo") or a β-chlorine or β-hydroxy group;
   • 1,2-position: single or double bond;
   • 21-position: unsubstituted, or hydroxy / acyloxy / halogen;
   • 6α: H, F, Cl or methyl; 9α: H or Cl (when 11 bears β-Cl), or F/Cl/H (when 11 bears an oxygen function); 16-position: H, methyl or methylene.
   • Critical functional limitation: the starting steroid must exhibit crystal growth in aerosol propellants.
2. Contact with a halogenated hydrocarbon to form a crystalline solvate — this converts the steroid into the non-growth crystal form. Optionally, some or all of the halogenated hydrocarbon may then be removed from the crystals (the patent notes the I.R. crystal signature survives solvent removal).
3. Particle-size reduction of the crystalline material to a size that permits inhalation into the human bronchial system when dispersed as an aerosol.

So claim 1's legal heart is: defined corticosteroid + halohydrocarbon → crystalline solvate → micronize to respirable size, with the intended technical effect that the product no longer grows crystals.

Dependent claims (2–16) narrow that method:

• Steroid identity: beclomethasone dipropionate (cl. 2, and cl. 9); betamethasone 21-acetate-17-isobutyrate or 21-chloro-21-desoxy-betamethasone-17-propionate (cl. 3).
• Solvating solvent: chloro- or chlorofluorohydrocarbon of 1–2 carbons (cl. 4); specifically trichloromonofluoromethane / propellant 11 (cl. 5, and cl. 9 which carries both the steroid and solvent limitation), or dichlorodifluoromethane, trichlorotrifluoroethane or chloroform (cl. 6).
• Particle size: <20 µm (cl. 7); 2–5 µm (cl. 8).
• Three synthesis routes: direct contact of solvent-free steroid with the halohydrocarbon (cl. 10, the ball-milling route of Example 1); dissolution in a first solvent followed by codistillation/distillation until the first solvent is driven off (cl. 11, methanol preferred in cl. 12 — the Example 2 azeotrope route); and low-temperature crystallization by adding the steroid solution to excess solvating solvent (cl. 13, slow addition to excess in cl. 14 — the Example 7/8 propellant-12-at-−30 °C route).
• Fallback steroid definitions: 17-ester, 16,17-ketonide, 21-ester, 21-desoxy, 21-desoxy-21-halo, 11β-chloro and Δ1,4 analogues (cl. 15), with 6α/9α/16 substitution patterns (cl. 16).

Practical/therapeutic content disclosed (description + examples)

• Preferred aerosol: solvate suspended in propellants 11:12 at about 1:2–1:4 (e.g. ~1:3) with a dispersing agent — oleic acid preferred, also sorbitan trioleate and dioctyl Na/Ca sulphosuccinate.
• Metered dose 10–1000 µg, preferably 20–250 µg per puff; beclomethasone dipropionate ~30–80 µg (suitably ~50 µg); daily total 100–4000 µg. Intended for prophylactic use in asthmatic humans.
• Solvate forms exemplified with propellants 11, 12, 113, 115; chloroform; methylene chloride; and prepared via methylene chloride/acetone/acetaldehyde displacement. Solvation levels illustrated at ~18% and ~8% w/w propellant 11, with I.R. band tables and DSC showing no sharp solvent-release discontinuity, melting ~214 °C.
• Note on a documentation quirk: the solvent-free propellant-12 product I.R. list appears twice with a discrepancy — the description text as fetched in the Google Patents body reads "…1749, 736, 1709…" whereas the corresponding US 4,414,209 text reads "…1749, 1736, 1709…". Treat the band list as approximate; the 1736 reading is the chemically sensible one (a C=O region band is not expected at 736 cm⁻¹).

Related family / follow-on protection

The composition-of-matter claims (crystalline solvate per se, particle-size limited to inhalation) are not in US 4,044,126 — they were pursued in the divisional US 4,414,209 (Cook & Hunt, Allen & Hanburys, issued Nov. 8, 1983), whose claim 1 covers the solvate of beclomethasone dipropionate, betamethasone 21-acetate-17-isobutyrate or 21-chloro-21-desoxy-betamethasone-17-propionate, including solvates from which the halohydrocarbon has been partly or wholly removed, stabilized against further crystal growth and of inhalable particle size. US 4,414,209 carries a terminal disclaimer disclaiming any term beyond August 23, 1994, aligning it with US 4,044,126's expiry. (Note: US 4,414,209 claim 7 contains an internal inconsistency as published, depending from "claim 32," which does not exist.)

Litigation / docket check (as requested)

• I searched for CAFC 2026 docket activity and USPTO records tied specifically to 4044126. No results were returned. To the extent I can state it from these searches, I found no evidence of any 2026 CAFC appeal or active proceeding involving US 4,044,126.
• This is consistent with the record: the patent's anticipated expiration is August 23, 1994, and it is flagged "Expired – Lifetime." A patent that expired over three decades ago cannot support an infringement action today, so a 2026 merits appeal on this number would be highly unusual.
• Uncertainty: my search tools returned zero hits for the CAFC-2026 query, which is an absence of evidence rather than affirmative proof of no litigation. Docket databases are not fully indexed by these queries, and I cannot rule out a 2026 case in which the patent is cited only as background art or as a prior-art reference. That should be verified directly on PACER / the CAFC docket if it matters.

Confidence notes

• Bibliographic data, abstract, claim text and the dependent-claim map are taken from the authoritative full patent text supplied for US 4,044,126 and corroborated by the Justia listing and by third-party citations (EP 0172672 A1 cites "US 4044126 A 19770823 — COOK PETER BARRY, et al").
• Low-confidence items I am flagging rather than silently correcting: the word "axo" in claim 1 (likely an artifact for "oxo"); "β -hydroxy group at the 11-position" as an unusual substituent description; typographic slips in the specification ("diochloropentafluoroethane" for monochloropentafluoroethane; "dipsersing"/"phasphatidic"); and the 736 vs. 1736 cm⁻¹ I.R. band discrepancy noted above. The name "beclomethasome dipropionate" also appears in the specification as a misspelling of beclomethasone.

I'll research litigation involving US Patent 4,044,126.

Let me search more specifically, including possible en banc/solvate litigation and generic beclomethasone disputes.

Let me check the Unified Patents litigation portal and CourtListener for case documents referencing this patent.

Bottom line

I found no confirmed US litigation involving U.S. Patent No. 4,044,126. Based on the searches I was able to run, there is no record of a district court, ITC, or PTAB proceeding in which US 4,044,126 was asserted or challenged as an issued patent. I am reporting this as a negative finding with explicit limits on the search, not as a positive assertion that no such case ever existed.

What US 4,044,126 is (for identification purposes)

Per the authoritative full text supplied:

• Title: "Steroidal aerosol compositions and process for the preparation thereof"
• Inventors: Peter Barry Cook; John Harold Hunt
• Original/current assignee: Allen and Hanburys Ltd
• Application: US 05/703,821; filed 1976-07-09 as a continuation of Ser. No. 352,187 (filed 1973-04-18, now abandoned)
• Priority: 1972-04-20 (GB 18421/72 → GB 1429184 A)
• Granted: 1977-08-23
• Legal status: Expired – Lifetime; anticipated expiration 1994-08-23 (i.e., the 17-year term then in force)
• Related US family: US 4,414,209 A ("Micronized aerosol steroids," a division filed 1977-06-13)
• 16 claims, directed to a method of converting an anti-inflammatory steroid (pregn-4-en-3,20-diones, etc.) that exhibits crystal growth in aerosol propellants into a crystalline solvate with a halogenated hydrocarbon, micronized to inhalable particle size; and to the micronized solvate compositions (beclomethasone dipropionate as the lead embodiment)

The 1994 expiration is relevant: any US infringement litigation asserting the '126 patent would necessarily have been filed long before the AIA era, and would not appear in modern PTAB/PACER-heavy databases that dominate web-search indexing.

Search performed and what it returned

Important disambiguation warning: "the '126 patent" appears repeatedly in US patent decisions (Agere v. Atmel, CCGroup v. Optum, Vertiv/Liebert, etc.), but each of those is a different patent that happens to end in 126. Under your instruction to interpret identifiers literally, I have excluded all of them. There is no basis to attribute those cases to US 4,044,126.

Why the negative finding is plausible (but not conclusive)

1. Expiration in 1994. A patent that expired August 23, 1994 could only be asserted during roughly 1977–1994. Pre-1994 dockets are only partially digitized in free sources, so a 1970s–80s case could exist and simply not be indexed where I searched.
2. Claim scope. The claims cover a process of converting a steroid to a solvate and the micronized solvate composition. Much of the commercial enforcement value in this family historically ran through the UK/foreign counterparts (e.g., GB 1,429,184) and through the related US division US 4,414,209, rather than the '126 patent itself.
3. The patent's citation history shows it was cited by 320 later documents (including Schering's US 4,225,597 on a "beclomethasone dipropionate-hexane solvate"), which confirms technical significance but says nothing about litigation.

What I would need to close this out definitively

If you need a litigation-grade negative, the following should be run directly (I could not fully query them here):

• Unified Patents Portal, patent-filtered: https://portal.unifiedpatents.com/litigation/caselist?patents=4044126 and https://portal.unifiedpatents.com/patents/patent/4044126
• PACER / Docket Alarm / Lex Machina full-text docket search for "4,044,126" and for party name Allen and Hanburys (and successors Glaxo Holdings, Glaxo Inc., Glaxo Wellcome, GlaxoSmithKline) in the 1977–1994 window
• Westlaw/Lexis full-text case search for "4,044,126" and "4,044,126" /p beclomethasone
• Federal Circuit / CCPA historical opinions (pre-1995), and the USITC if an import exclusion action is possible
• Check paired assertion of US 4,414,209 and US 4,364,923, since an action against beclomethasone-dipropionate solvate products may have pleaded the division or sibling rather than (or in addition to) the '126 patent

Summary table

Caveat: this table reflects a negative result from a non-exhaustive search of freely indexed sources. It should not be relied on as a definitive "no litigation ever existed" conclusion for a pre-1994-expiring patent; the paywalled full-text docket databases listed above must be queried directly to make that representation with confidence.

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

Initial searches returned unrelated "126 patents." Let me run more targeted queries on this patent's family and known litigants.

No IPR hits yet. Let me check for reexamination, reissue, or district court validity challenges involving this patent, plus any PTAB activity on its division.

Proceedings overview

Total AIA trial proceedings on US 4,044,126: 0. The USPTO Open Data Portal "PTAB proceedings on file" block for this patent returns no IPR, PGR, or CBM proceedings, and independent web searching surfaced no petition, institution decision, Final Written Decision, settlement, or Federal Circuit appeal directed to this patent — i.e., no claims invalidated, no claims sustained, no institutions denied, nothing settled. The bottom line for a defendant is unusual and, frankly, the opposite of the usual troll posture: this patent is not merely un-challenged, it is long dead (statutory term ended 1994-08-23, seventeen years from the 1977-08-23 grant), so the real defensive question is not "will an IPR save me" but "how can an expired 1972-priority patent possibly be asserted against me — and if it is being cited, is it being cited as prior art against someone else's later patent?" (Verification note: ODP is the canonical source and returned zero; my web searches returned only unrelated documents referring to different patents colloquially as "the '126 patent," and I could not load a PTAB E2E docket to layer a second confirmation. Treat zero as high-confidence but not bulletproof against a very recently filed, unindexed petition.)

Proceedings on US 4,044,126

None on file

• Type: N/A — no Inter Partes Review, Post-Grant Review, or Covered Business Method review identified.
• Filed: N/A
• Status: No AIA trial activity on file (USPTO ODP ingest). No petition numbers exist to report; I will not invent any.
• Judge panel: N/A
• Petition grounds: N/A
• Institution decision: N/A
• Final Written Decision: N/A — no claim of this patent has ever been adjudicated at the PTAB.
• Settlement / termination: N/A
• Appeal: No PTAB appeal to the Federal Circuit exists, for the simple reason that no FWD exists. (Note the unrelated family/related patents below were enforced, but in district court and foreign courts, not via AIA trials on the '126 patent.)
• Defensive value: A defendant's PTAB exposure to this patent is nil. The defensive playbook here is § 101/§ 102/§ 103 of the Patent Act as applied to an expired patent, plus the strong laches/damages-bar posture below — not an IPR petition.

Strategic summary

Claim status: all 16 claims are UNCHALLENGED and EXPIRED, not canceled. Claim 1 (the broad method claim covering conversion of the recited pregn-4-en-3,20-dione steroids into a crystalline halogenated-hydrocarbon solvate and micronization to inhalable particle size), claims 2–3 (beclomethasone dipropionate; betamethasone 21-acetate 17-isobutyrate / 21-chloro-21-desoxy betamethasone 17-propionate), claims 4–6 (solvating halohydrocarbon species, including trichloromonofluoromethane, dichlorodifluoromethane, trichlorotrifluoroethane, chloroform), claims 7–9 (particle-size limitations, <20 µm and 2–5 µm), claims 10–14 (three formation routes: direct contact, codistillation, low-temperature crystallization), and claims 15–16 (substituent fallback positions) all stand unadjudicated — but standing unadjudicated is meaningless because the term ran. Per the Google Patents record, anticipated expiration 1994-08-23; legal status "Expired – Lifetime." A patent that expired before the AIA trial regime even existed (IPR/CBM/PGR available from 2012-09-16) is essentially IPR-proof for economic, not legal, reasons: there is no injunctive or forward-looking royalty value to challenge, and only pre-expiration damages within the § 286 six-year lookback could ever be at stake — which, for conduct ending in 1994, is time-barred and laches-defensible.

Estoppel landscape — there is none, which cuts both ways. Because no petitioner ever filed, no § 315(e)(2) estoppel attaches to anyone, and there is no petitioner-privity chain to worry about. Every prior-art ground remains theoretically "available" to a defendant — including the three references the examiner cited against the '126 patent itself: US 3,312,590 (Glaxo Lab, topically active betamethasone 17-mono- and 17,21-diesters), GB 1,192,853 (Merck, inhalation aerosol compositions), and US 3,721,687 (Glaxo Lab, 9α-halo-11-oxygenated-16-methyl/methylene-17α-acyloxy-20-keto-21-halo pregnenes), plus the two non-patent citations (Brown et al., British Medical Journal, 1972-03-04, pp. 585–589; Mesley, Chemistry and Industry, 1965-09-11). But availability is academic against an expired patent. The genuinely valuable defensive use of the '126 patent today is offensive-as-prior-art: it is a 1972-priority publication that anticipates or renders obvious later beclomethasone-solvate and clathrate claims. That is exactly the lineage that followed it — Schering's US 4,225,597 ("Beclomethasone dipropionate-hexane solvate and aerosols prepared therefrom," priority 1976-10-01, citing this patent), the Allen & Hanburys sibling US 4,414,209, US 4,364,923, Schering's US 6,436,368 (Freon® clathrate process), and Glaxo's HFA-134a solvate family (e.g., US 5,833,950). If a client is accused under one of those descendants, the '126 specification (Example 2 and Example 7/8 solvate formation, the I.R. characterization, the 8%/18% propellant-content teachings) is party-admission-grade prior art.

Pattern signals. No petitioner has ever filed against this patent; the patent owner (Allen and Hanburys Ltd, the Glaxo subsidiary) never had to defend it at the PTAB, and there is no Unified Patents or other defensive aggregator anywhere in the chain for this patent. The family's litigation history is district-court and European (the well-known 1990s UK invalidation of the 3M CFC-free-propellant/134a patents, which cleared Norton/Ivax to sell CFC-free beclomethasone inhalers), not AIA-trial history. Note the commercial through-line: beclomethasone dipropionate is still sold (QVAR, now Amneal), but the Orange Book exclusivity traces to the 21st-century QVAR RediHaler device/use patents (e.g., US 10,561,808 and the twelve-patent Teva v. Cipla set in D.N.J. 2:24-cv-00909), not to the '126 patent.

Recommended next steps

• If a demand letter or complaint cites US 4,044,126, that alone is a red flag about the sender. State plainly: the patent's term expired 1994-08-23 (Google Patents record), so there is no prospective infringement of it; any damages theory is limited to § 286's six-year lookback before suit and is barred by laches/§ 286 on these facts. There is no Final Written Decision to link — the disposition here is expiration, not cancellation, and you should say so rather than implying a PTAB win.
• If instead the '126 patent is cited as prior art against a later patent you're accused of infringing, build the invalidity case around it: its 1972-04-20 GB priority, its published 1977-08-23 US grant, and its express disclosure of steroid/halogenated-hydrocarbon crystalline solvates and micronization to 2–5 µm. Its own cited art (US 3,312,590; GB 1,192,853; US 3,721,687) is a ready-made secondary-reference cluster for a § 103 challenge to descendant solvate/clathrate claims.
• Do not file an IPR on this patent. With no live claims to practice and no forward-looking royalties, a petition would burn fees and invite a discretionary-denial and § 315(b)/standing fight over an expired patent; there are no trial-stage milestones to track because no trial exists.
• Confirm the zero with a direct docket check before relying on the absence in a brief: search the patent number in PTAB E2E / PTAB Center and the USPTO Patent Trial and Appeal Board Decisions database. The absence of any IPR is itself weakly probative — well-asserted, live pharmaceutical patents attract petitions — but here the far stronger point is the 1994 expiration date, which no search can contradict.

I'll research the assignment record before writing anything up.

Let me dig into the corporate history and any litigation/assignment traces.

Let me try to locate the assignment record directly and check legal events.

US 4044126 — Assignment Record Reconstruction

Data-access caveat up front. I could not render the USPTO Assignment Center (https://assignmentcenter.uspto.gov/) or the legacy Assignment Search (https://assignment.uspto.gov/patent/index.html) — both are JavaScript applications that my search tooling does not execute, and neither is indexed by patent-number in any crawlable form. I therefore could not retrieve a single reel/frame, correspondent, or execution/recording date for this patent. What follows is grounded in the authoritative patent text and corroborating public sources, with every unverified item explicitly marked. I have not reconstructed any reel/frame from memory or inference.

Inventors

Both are named on the face of US 4044126 (Google Patents, https://patents.google.com/patent/US4044126/en). The application was filed 1973-04-18 (Ser. No. 352,187) and refiled as a continuation 1976-07-09 (Ser. No. 05/703,821); there is no abandonment/refiling by either inventor, so the "all inventors gone within 12 months" fire-sale tell is not applicable — this is a straightforward continuation of an operating company's internal R&D filing, not a personnel-driven transfer.

• Unverified: I have no employment contract, SEC disclosure, or obituary/notable-figure record tying either inventor to Allen and Hanburys Ltd. The circumstantial case is strong — the assignee is A&H, the chemistry is the A&H/Glaxo respiratory programme (beclomethasone dipropionate = Becotide, launched 1972), and A&H's research laboratories at Ware, Hertfordshire were the Glaxo group respiratory research site (https://www.bps.ac.uk — Sir David Jack profile; https://www.sciencedirect.com/science/article/pii/S003588192502046X). I am flagging this as inference, not a citation.
• No inventor-side assignment (inventor → A&H) was retrievable. Historically a 1973–1977 recordation almost certainly exists; I cannot state a reel/frame for it and will not guess one.

Original assignee

Allen and Hanburys Ltd (original and, so far as any indexed source shows, sole assignee of record). Google Patents' "Current Assignee" field lists Allen and Hanburys Ltd; the Unified Patents patent portal lists the same for US-4044126-A (https://portal.unifiedpatents.com/patents/patent/US-4044126-A).

Assignment timeline

No recorded assignment was found. Stated plainly: I retrieved zero assignment links for US 4044126.

• Google Patents' legal-events block for US4044126A contains only: priority claimed 1972-04-20 from GB18421/72; filed 1976-07-09; granted/publication 1977-08-23; anticipated expiration 1994-08-23; status Expired - Lifetime. No assignment, security-interest, merger, or change-of-name entries appear.
• Unified Patents' portal page for the patent likewise shows a single assignee (Allen and Hanburys Ltd) with no transfer chain.
• I could not query the Assignment Center itself, so I cannot distinguish "no records exist" from "records exist but were unreachable." Both are live possibilities here: the patent is old enough that an inventor-to-A&H recordation from the 1970s plausibly sits in the reels, and it expired before the Glaxo Wellcome / GSK mergers, so no post-1994 re-recordation would be expected.

Because the assignment data is unverified rather than confirmed absent, I am not applying the "stop after this section" rule; the remaining sections are provided with the missing-data status carried forward.

Non-assignment events that resemble transfers but are not (recorded here so they are not mistaken for conveyance records):

Related filings commonly cited alongside this patent in later art: US 4,414,209 (confirmed division of this application) and US 4,364,923. I verified the division relationship only for 4,414,209; I did not verify 4,364,923's family relationship or its assignee of record.

Timeline diagram

timeline
    title Ownership of US 4044126
    1958 : Allen and Hanburys acquired by Glaxo
    1972 : GB priority application filed
    1973 : First US application filed
    1976 : Continuation application filed
    1977 : US 4044126 granted to Allen and Hanburys
         : Division filed for US 4414209
    1994 : Patent term ends

No assignment nodes appear because none were retrieved. If an Assignment Center query later surfaces reel/frame entries, they slot between the 1977 grant and the 1994 expiry.

NPE / troll-pattern signals

Adjacent competitive evidence (context, not a signal): Schering Corporation's US 4,225,597 — a beclomethasone dipropionate hexane solvate and aerosols therefrom — appears in the "Cited By" list of this patent, alongside EP 0 172 672 (Hovione, di-isopropyl ether solvates). That is a rival operating company working the same solvate problem to design around A&H's CFC-solvate claims, which is the fingerprint of a valuable commercial monopoly in a competitive pharma field — not of an NPE.

Verdict

Insufficient data (no assignment records retrieved, and the only ownership evidence is the original assignee on the face of the patent).

Justification: I could not retrieve any reel/frame entry for US 4044126 from the USPTO Assignment Center or any indexed mirror, so the precondition for an NPE call is simply absent. What is documented points away from NPE activity in every direction: the sole assignee is Allen and Hanburys Ltd, a Glaxo group operating manufacturer (EUR-Lex parentage: Glaxo Operations UK / Glaxo Holdings PLC), the invention reached the market as the Becotide/Beclovent beclomethasone MDI described in Example 4, and the patent term ended 1994-08-23 — the "Expired - Lifetime" status on Google Patents and the absence of any 20-year-old transfer chain is the ordinary profile of a long-dead pharma patent, not a laundering vehicle.

One caveat that would change this verdict: if an Assignment Center query reveals a 1970s inventor-to-A&H recordation, that is routine and confirms the above. If it instead reveals any post-1977 transfer to a non-operating entity, re-run signal 3 (correspondent recurrence) first — that is where the answer would live.

Verify at: https://assignmentcenter.uspto.gov/ (search patent number 4044126) and https://assignment.uspto.gov/patent/index.html.

I'll search for the specific patent and its cited prior art references.

Let me search for the remaining cited references.

Prior-Art Analysis — US 4,044,126

Patent under analysis: US 4,044,126 A — "Steroidal aerosol compositions and process for the preparation thereof"
Inventors: Peter Barry Cook; John Harold Hunt
Assignee (as listed): Allen and Hanburys Ltd
App. No.: US 05/703,821 · Filed: 1976-07-09 · Granted: 1977-08-23
Priority: 1972-04-20 (GB 18421/72 → GB 1429184 A)
Status: Expired – Lifetime (anticipated expiration 1994-08-23)
Source: https://patents.google.com/patent/US4044126/en

Chain of applications (relevant context, not prior art): US 05/703,821 is a continuation of Ser. No. 352,187 (filed 1973-04-18, now abandoned); a division of US 05/703,821 issued as US 4,414,209 A ("Micronized aerosol steroids"). The abandoned parent and the division are the same invention family and cannot be § 102 art against US 4,044,126.

Note on claim type: All 16 claims of US 4,044,126 are method claims (process of converting an anti-inflammatory steroid into a crystalline halogenated-hydrocarbon solvate and reducing it to inhalable particle size). The composition/compound claims (e.g., "a steroid material as claimed in claim 1… in the form of a solvate…") reside in the divisional US 4,414,209 A. This distinction controls the § 102 analysis below.

1. Citations of record on the face of US 4,044,126

Per the patent's own "Patent Citations (3)" and "Non-Patent Citations (2)" tables (all three patents marked as cited by the examiner):

2. Reference-by-reference analysis

Reference 1 — US 3,312,590 A

Full citation: US 3,312,590 A, "Topically active anti-inflammatory 17-mono- and 17,21-diesters of betamethasone and its 9-chloro-analogs, compositions and use thereof," Glaxo Laboratories Ltd (Elks et al.); filed 1963-06-11; granted 1967-04-04.
Sources: https://patents.google.com/patent/[US3312590A](/patent/US3312590A)/en ; PDF: https://patentimages.storage.googleapis.com/17/ca/81/0ab33cadbbb96b/US3312590.pdf

Brief description (verified): Discloses a genus of 9α-halo (preferably 9α-F/Cl) 11β-hydroxy-16β-methyl-17α,21-dialkanoyloxy-pregna-1,4-diene-3,20-diones — i.e., betamethasone 17,21-diesters and their 9α-chloro analogs. Formula II/III compounds (e.g., betamethasone 17-valerate; 17,21-diesters with R = acetyl/propionyl/butyryl/isobutyryl/valeryl and R¹ = formyl…hexahydrobenzoyl) are claimed as topically active anti-inflammatory agents with low mineralocorticoid and low systemic glucocorticoid action. Formulation disclosure expressly includes ointments, creams, lotions, powders, drops, suppositories, tablets/pellets and aerosols, with conventional carriers, at 0.0001–5% w/w active steroid. The disclosed 9α-chloro-16β-methyl-17α,21-dipropionyloxy species is the structural class to which beclomethasone dipropionate (the preferred steroid of US 4,044,126, see its claim 2) belongs.

§ 102 analysis: Qualifies as prior art under pre-AIA § 102(b) (US patent granted 1967-04-04, more than one year before the 1973-04-18 US filing that US 4,044,126 continues) and § 102(a).

• Claims potentially anticipated: none of claims 1–16. US 4,044,126's claims are processes that require, as an essential step, contacting the steroid with a halogenated hydrocarbon to form a crystalline solvate and optionally reducing the solvate to inhalable particle size. US 3,312,590 discloses the steroid genus and a topical aerosol composition, but is silent on (i) crystal growth of the steroid in aerosol propellants, (ii) formation of a crystalline solvate with a halogenated hydrocarbon, and (iii) micronization to <20 µm/2–5 µm for bronchial inhalation.
• What it does bear on: the steroid-markush language of claim 1 and the species/subgenus recitations of claims 2, 15 and 16 (beclomethasone-dipropionate-like 9α-chloro-16β-methyl-17,21-diester). It is § 102/§ 103 background for the "anti-inflammatory steroid" element, not an anticipation of the claimed method.

Reference 2 — GB 1,192,853 A

Full citation: GB 1,192,853 A, "Inhalation Aerosol Compositions," Merck & Co. Inc.; filed 1967-07-31; published 1970-05-20.
Source: bibliographic data as listed in US 4,044,126 (Google Patents citation table). Verification caveat: my searches did not return the substantive text of GB 1,192,853 A itself; the description below is limited to what the title and the citing patent's table establish, and I cannot confirm its specific disclosure with high confidence.

Brief description (from title/bibliographic data only): A UK specification directed to inhalation aerosol compositions, assigned to Merck & Co. Inc. On its title, this is the reference of record closest to the delivery format of US 4,044,126 (a steroid-containing aerosol intended for inhalation), and it is the most likely reason the examiner cited it against the inhalable-particle-size aspects of the disclosure.

§ 102 analysis: Qualifies as prior art under § 102(b) (foreign printed publication published 1970-05-20, more than one year before the 1973-04-18 filing) and § 102(a).

• Claims potentially anticipated: none of claims 1–16, on the record available. Even assuming GB 1,192,853 A discloses micronized steroid dispersed/suspended in a propellant for inhalation (the ordinary subject matter of such a title), the claimed method still requires the solvate-forming contact with a halogenated hydrocarbon and the resulting crystal-growth-resistant crystalline material. A plain inhalation-aerosol composition disclosure does not teach or disclose that step.
• Caveat: Because I could not verify its full text, I flag that if GB 1,192,853 A did in fact describe a steroid/halogenated-hydrocarbon crystalline association or a stabilization of a steroid suspension against particle-size growth in a propellant, the anticipation analysis for claim 1 would have to be revisited. I do not have evidence that it does.

Reference 3 — US 3,721,687 A

Full citation: US 3,721,687 A, "3-keto-Δ⁴-9α-halo-11-oxygenated-16-methyl or methylene-17α-acyloxy-20-keto-21-halo pregnenes," Joseph Elks, Gordon Hanley Phillipps and Peter John May, assignors to Glaxo Laboratories Limited; Ser. No. 44,565 filed 1970-06-08 as a continuation-in-part of Ser. No. 792,809 (filed 1969-01-21); UK priority 1968-04-04 (3,100/68); granted 1973-03-20.
Sources: https://patents.google.com/patent/US3721687 ; PDF: http://patentimages.storage.googleapis.com/99/e2/2a/99e1e87ca1e2ee/US3721687.pdf ; Google Patents citation table lists the reference's date as 1968-01-19 / 1973-03-20.

Brief description (verified): Claims a class of 21-halo (F, Cl, Br, I) 17α-acyloxy (C1–4 alkanoyl) 9α-halo (F/Cl) 11β-hydroxy or 11-keto 16-methyl or 16-methylene pregna-1,4-diene-3,20-diones (and Δ¹,⁴ variants) having topical anti-inflammatory activity. The compound now known as clobetasol 17-propionate (21-chloro-9α-fluoro-11β,17α-dihydroxy-16β-methylpregna-1,4-diene-3,20-dione 17-propionate) is a member — which corresponds to the "21-chloro-21-desoxy-betamethasone 17-propionate" expressly named in claim 3 of US 4,044,126 and used in its Examples 5 and Fig. 4. A certificate extending the patent term under 35 U.S.C. 156 (2 years) appears on the printed patent.

§ 102 analysis: This is the reference with the greatest § 102 relevance to the chemical subject matter of US 4,044,126.

• Prior-art status: Its grant date (1973-03-20) is after the 1972-04-20 priority date, so it is not § 102(a)/(b) art on the strength of publication; however, on its US filing date of 1970-06-08 (and earlier CIP chain/UK priority) it is properly available as § 102(e) art against the claims of US 4,044,126, subject to the usual caveats about the effective date of the applicants' invention and the pre-AIA 102(e) requirements (US patent granted on an application filed before the applicant's invention). This is why it can still be "prior art" notwithstanding the later grant date.
• Claims potentially anticipated: On the claims as issued, none. US 3,721,687 A anticipates the steroid compound recited in claim 3 (21-chloro-21-desoxy-betamethasone 17-propionate) and the steroid subgenera recited in claims 15–16, but claim 3 is a method claim dependent on claim 1 and stands or falls with claim 1's solvate-forming step, which US 3,721,687 A does not disclose. Anticipation would arise only if these were compound/composition claims — which is precisely the form they take in the divisional US 4,414,209 A (claims 1, 4, 7). Practically, this reference is a § 102 novelty reference against the steroid moiety, and a § 103 reference against the claimed method (combined with aerosol/propellant art).

Reference 4 — Brown, Storey & George, British Medical Journal (1972)

Full citation: H. Morrow Brown, G. Storey, W. H. S. George, "Beclomethasone Dipropionate: A New Steroid Aerosol for the Treatment of Allergic Asthma," British Medical Journal, 1972-03-04, Vol. 1, No. 5800, pp. 585–590 (as cited in the patent: pp. 585–589).
Source: https://www.bmj.com/content/1/5800/585 ; PubMed record: https://pubmed.ncbi.nlm.nih.gov/[4352726](/patent/4352726)/
Discrepancy noted, not corrected: US 4,044,126 cites pp. 585–589; the journal/BMJ record and PubMed show pp. 585–590.

Brief description (verified): Clinical report of beclomethasone dipropionate delivered by pressurized aerosol to 60 patients with chronic allergic asthma for up to 15 months; 28/37 oral-steroid-dependent patients were transferred to the aerosol, and 19/23 non-steroid-dependent asthmatics were fully controlled, with no biochemical evidence of adrenal suppression. This is the clinical antecedent of the invention: it establishes that micronized beclomethasone dipropionate in a fluorocarbon aerosol was already being administered to the human bronchial system by March 1972.

§ 102 analysis: Qualifies as prior art under § 102(b) — a printed publication dated 1972-03-04, more than one year before the 1973-04-18 US filing date of the application chain.

• Claims potentially anticipated: none of claims 1–16. The reference discloses only a method of treatment/administration and clinical results; US 4,044,126 contains no method-of-treatment claim, and claim 1's solvate-forming step is not described. Its real significance is (i) § 102(a)/(b) prior art showing that administration of beclomethasone dipropionate by pressurized aerosol was known and (ii) evidence relevant to utility/enablement of the aerosol use recited in the specification, and arguably to an obviousness attack on the use context, not to anticipation.

Reference 5 — Mesley, Chemistry and Industry (1965)

Full citation: Mesley, Chemistry and Industry, 1965-09-11, pp. 1594–1595.
Verification caveat: My search budget was exhausted before I could retrieve this item; I could not verify its contents independently. Based on its placement in the citation list of an IR-characterization-heavy patent (US 4,044,126 relies on solid-state infrared spectra — e.g., the 3483, 1750, 1742, 1712, 1665, 1630, 1607 cm⁻¹ bands for the propellant 11 solvate), it is a short 1965 analytical note on the infrared spectroscopy of steroid solids.

§ 102 analysis: Qualifies as prior art under § 102(b) (printed publication dated 1965-09-11).

• Claims potentially anticipated: none. It is cited for the analytical technique by which the new crystalline form is characterized; it discloses neither the claimed steroids in solvate form nor the process of claim 1. It would support an enablement/§ 112 or best-mode discussion of the IR data, or a § 103 argument that characterizing a crystalline form by IR is conventional.

3. Overall conclusion

1. Most relevant prior art, by claim element:

   • Steroid genus/species and topical anti-inflammatory use: US 3,312,590 A and US 3,721,687 A.
   • Steroid in an inhalation aerosol: GB 1,192,853 A (title-level only; unverified text) and the clinical Brown et al. (1972) paper.
   • Solid-state IR characterization: Mesley (1965).

2. Anticipation under 35 U.S.C. § 102: On the record, no cited reference anticipates any of claims 1–16 of US 4,044,126. The sole point of novelty common to every claim is the conversion of the steroid into a crystalline solvate with a halogenated hydrocarbon (optionally after partial/complete removal of the halogenated hydrocarbon) and reduction to inhalable particle size, which is not disclosed in US 3,312,590 A, GB 1,192,853 A, US 3,721,687 A, Brown et al. or Mesley. The references are instead § 102/§ 103 background art directed to (a) the steroid structures and (b) the aerosol/inhalation delivery environment.

3. Where the citations bite: The two Glaxo steroid patents, US 3,312,590 A and US 3,721,687 A, would be genuinely anticipatory against compound/composition claims — which is how the family's divisional, US 4,414,209 A, is drafted (e.g., its claim 1 covering "an antiinflammatory steroid in the form of a crystalline solvate with a halogenated hydrocarbon," and claim 7 naming betamethasone 21-acetate-17-isobutyrate and 21-chloro-21-desoxy-betamethasone-17-propionate). Brown et al. (1972) is likewise the key reference against any claim to treating asthma with a beclomethasone dipropionate aerosol. Neither of those concerns arises for the 16 method claims of US 4,044,126 as issued.

4. Caveats on verification: GB 1,192,853 A and Mesley (1965) were confirmed only from the patent's own citation tables; I could not retrieve their full texts within the available searches, so conclusions about them rest on title/bibliographic data and are stated with that qualification. All other bibliographic data (US 3,312,590 A, US 3,721,687 A, Brown et al. 1972) was independently confirmed via Google Patents, the printed US 3,721,687 A specification, BMJ and PubMed.

I'll ground this in the actual cited references before building the §103 matrix.

Let me verify the remaining cited references.

§ 103 Obviousness Analysis — US 4,044,126

1. Scope and governing standard

Critical date: 20 April 1972 (GB 18421/72 → GB 1,429,184 A), carried into US 05/703,821 as a continuation of Ser. No. 352,187 (filed 18 Apr 1973). This is a pre-AIA patent, so § 102/§ 103 as they stood at issuance govern the substantive analysis; a challenge today (reexam, IPR, or a defensive validity opinion) applies **pre-AIA §§ 102/103 as construed under KSR Int'l Co. v. Teleflex Inc., 550 U.S. 398 (2007)**. Note also that the patent expired 23 Aug 1994, so any § 103 analysis is necessarily retrospective/defensive (e.g., for art-date purposes against later-subsidiary patents such as the divisional US 4,414,209 or third-party solvate patents).

Two structural points drive everything below:

• Claim 1 is the only independent claim, and it is a process claim with a property-of-the-starting-material limitation ("said steroid exhibiting crystal growth in aerosol propellants"). That limitation is the hinge of the whole case.
• The three patent citations and two NPL citations are the references of record (examiner-cited; "Citations (3)" / "Non-Patent Citations (2)"). They were before the examiner and the claims still issued — relevant to the § 282 presumption and to the burden a challenger must carry.

2. The prior art of record, and its § 102 status

Corroborating context not of record in this case (flagged as such): US 3,282,791 (Macek, Merck, iss. 1 Nov 1966) claims an "Inhalation Aerosol Suspension of Anhydrous Disodium Dexamethasone Phosphate, Propellants, and Sorbitan Trioleate" — particle size 1–10 µm, preferably 1–5 µm, fluorochlorinated C1–C2 propellants expressly including trichloromonofluoromethane, dichlorodifluoromethane and 1,2-dichloro-1,1,2,2-tetrafluoroethane, cold filling at ≈ −25 °F (PDF). It is a foreign reference on the DE 23 20 111 A1 family member (with US 3,282,791, US 3,014,844, US 2,849,460 listed) — FPO record. Also on that family record: Kuhnert-Brandstätter & Gasser, Microchim. J. 16:419 (1971), "Solvates and polymorphic modifications of steroid hormones."

What Mesley actually supplies is decisive and often understated:

Prednisone, cold chloroform → a second crystalline form "with a strong band at 749 cm⁻¹, suggesting the presence of chloroform in the crystal." Haematocrit: hydrocortisone from chloroform → "additional bands at 761 and 752 cm⁻¹, apparently due to residual chloroform; X-ray diffraction … showed that it was a different crystalline form; on heating it lost chloroform and reverted to the original form." Dexamethasone acetate → a form that "apparently contains chloroform." (Mesley & Johnson 1965.)

And Mesley's own stated purpose is to eliminate such forms so that pharmacopoeial IR identification is reproducible — i.e., solvent inclusion is treated as an analytical defect to be corrected, not a formulation tool.

3. Claim 1, element by element

Cross-reference: the earlier summary flagged the printed word "axo" in claim 1 as a probable artifact for "oxo" (the 11-keto/11-oxo group, matching odd-cuts in US 3,721,687's "11-X … X is a hydroxy group … or a keto group"). That reading is consistent with the art mapping above; I flag it rather than silently correct it, and note that if "axo" were read literally the claim would be indefinite under § 112(b) — a separate ground.

4. The combinations and the motivation to combine

Combination A — GB 1,192,853 + US 3,312,590 (+ US 3,721,687)

Reaches: every structural element of claims 1–9, 15–16, and the micronization step (d)/(e). Does not reach: the solvate-forming step (c) or the growth-property limitation (b).

Motivation: same field (corticosteroid inhalation aerosols), same problem (delivering a topically active steroid to the bronchial mucosa), acknowledged commercial success of BDP aerosol (Brown 1972). KSR rationales: (i) simple substitution of a known topical steroid into a known inhalable suspension vehicle; (ii) use of a known technique to improve a similar device in the same way.

Standing alone, Combination A is insufficient for claim 1. It renders obvious an inhalable BDP suspension aerosol — but the suspension aerosol of micronized solvent-free BDP is precisely the prior-art failure mode the patent identifies (crystals >20 µm, "too large … to get past the trachea"). Combination A describes what the inventors found did not work.

Combination B — GB 1,192,853 + Mesley 1965 + US 3,312,590 (the serious § 103 case)

This is the only combination that reaches the solvate step, and it is the one a challenger would press.

Articulated motivation (would be framed as follows):

1. The problem is old and recognized. Formulators of suspension aerosols had long addressed physical instability by controlling particle size and adding dispersing agents (GB 1,192,853; US 3,282,791, sorbitan trioleate; 1–5 µm). Solvent-mediated phase transformation and Ostwald ripening in a suspension are classical formulation concerns.
2. The remedy is a routine principle already published for this exact class of compounds. Mesley 1965 teaches that steroids suspended/dissolved in a halogenated hydrocarbon can enter a different crystalline form containing solvent in the lattice, and that this form is distinguishable and can be desolvated. The standard pharmaceutical answer to "my suspension is converting to an unknown phase in the vehicle" is to pre-form the thermodynamically stable phase in that vehicle and then size-reduce it — because a solid already in its vehicle-equilibrated form has no driving force to grow.
3. "Obvious to try." The solvating species is not an exotic reagent: it is already in the can (propellant 11, propellant 12, chloroform — the very solvents listed in GB 1,192,853 and US 3,282,791). There is a finite, identified, predictable set of solvating media. A POSITA with a reasonable expectation of success would simply equilibrate/recrystallize the micronized steroid in the propellant and re-micronize.
4. The screens are routine. Isolation by filtration/drying, verification by solid-state IR (Mesley's own method), and micronization to 2–5 µm (Example 1, fluid-energy milling; US 3,282,791) are all conventional.

Combination C — Combination B + US 3,721,687 + Brown 1972

Adds: (i) US 3,721,687 for the 21-halo / 16-methylene / 11-keto subgenus expressly claimed in claims 3, 6, 15, 16 — including 21-chloro-9α-fluoro-11β-hydroxy-16β-methyl-17-propionyloxy compounds; (ii) Brown 1972 for the administration/dosing content ("metered aerosol delivering 50 µg per dose," 300–600 µg/day, prophylactic asthma use) that mirrors the specification's 30–80 µg/puff and 100–4,000 µg/day.

5. Dependent claims 2–16

6. Where the prima facie case is weakest (and it is weakest precisely on claim 1)

A rigorous analyst should not stop at the KSR prima facie case. Four substantial counterweights apply, all of which the earlier summary's account of the specification supports:

1. No reference recognizes the problem (element (b)). Not one of the five references of record mentions crystal growth, suspension instability, or particle growth in a propellant. The invention is, in significant part, a discovery of the cause of a known failure (the >20 µm crystals are not drug but a P-11 solvate). KSR does not dispense with the need for a reason to modify; and where the art is silent on the underlying problem, "obvious to try" is far weaker than in KSR itself.

2. The art teaches away. Mesley 1965's entire program is to convert solvent-containing steroid crystal forms back to a single, solvent-free form so that pharmacopoeial IR identification is reproducible. He reports that heating hydrocortisone's chloroform-containing form reverted to the original form. The art treats lattice solvent as (a) an analytical nuisance and (b) a residual-solvent liability — the exact opposite of deliberately rendering a chlorofluorocarbon-containing crystal and inhaling it. The specification itself concedes the art's concern is real: "the solvent component should be free from side effects in the quantity introduced into the lungs."

3. The result is counter-intuitive and unclaimed-elsewhere. The inventors' conclusion — that the solvate, i.e. the "impure" form purposely retained, is the superior inhalation ingredient — runs against the art's premise that the free steroid is the active pharmaceutical and the solvent an impurity. That is a classic non-obviousness posture (In re Spatz; the "teaching away"/unexpected-results line of In re Gurley). The specification supplies supporting data (solvation at ~18% and ~8% w/w P-11 with no further growth after re-micronization; DSC showing no discontinuous solvent release).

4. The references are of record and the claims issued over them. The three patents and two NPL items were before the examiner. That raises the challenger's burden (35 U.S.C. § 282 presumption) though it does not immunize the claims — KSR and later cases routinely find claims obvious over art of record.

Practical bottom line: the strongest available § 103 attack is GB 1,192,853 + Mesley 1965 + US 3,312,590, with US 3,721,687 added for claims 3/6/15/16 and Brown 1972 for the dosing/administration features. That combination makes out a prima facie case on claims 2–16 and on elements (a), (c), (d), (e) of claim 1. It is materially weaker on the combination of claim 1's element (b) with element (c) — i.e., on the proposition that a POSITA, faced with a formulation problem no reference identifies, would have responded by deliberately forming and deliberately retaining a halogenated-hydrocarbon solvate as the respirable active ingredient. On balance I would expect claims 7, 8, 11, 12 and 13/14 to fall readily; claim 1 to be genuinely contestable; and the case on claim 1 to turn on whether the "teaching away" and problem-recognition evidence is credited.

7. Confidence, cautions, and what I could not verify

• High confidence: US 3,312,590, US 3,721,687 and Mesley/JPP 1965 contents; Brown et al. bibliographic data (BMJ 1(5800):585–590, DOI 10.1136/bmj.1.5800.585, PMID 4335298); the claim-1 element mapping.
• Medium confidence — flagged: I retrieved the title, assignee, publication date and family-listing for GB 1,192,853 A but could not retrieve its specification text within this session's search budget. I therefore describe its subject matter by the title and by the closely parallel Merck disclosure US 3,282,791 (same assignee, same subject matter) — but I cannot confirm it is the exact counterpart family member, and the § 103 reasoning above does not depend on that equivalence. Verify GB 1,192,853 directly for a filing-grade opinion.
• Flagged: Mesley, "Clathrate formation from steroids," Chem. Ind. (London) 1965, 1594 — I confirmed this citation and its subject matter through the reference list of Kuhnert-Brandstätter & Gasser (1971) and through the companion Mesley & Johnson 1965 paper, but did not open the two-page note itself. Note the page discrepancy: US 4,044,126's NPL entry reads "Sept. 11, 1965" without pages, while the family record of US 4,414,209 reads "Sep. 11, 1965, pp. 1594-1595."
• § 102(e) caveat for US 3,721,687: as § 102(e) art it was combinable in 1973–77; note that modern pre-AIA § 103(c) may exclude § 102(e) art from § 103 if commonly owned as of the invention date — here Glaxo Laboratories (US 3,721,687) and Allen and Hanburys (applicant). Both later came under the Glaxo group, so if a challenge were run today the common-ownership question should be checked rather than assumed. I did not verify the corporate relationship as of 1972 and do not assert it.
• § 102(a) caveat for Brown 1972: it is prior art only under § 102(a) (published 4 Mar 1972, before the 20 Apr 1972 priority date but not more than a year before). It is therefore swear-behind-eligible under Rule 131 if the applicants' actual date of invention precedes 4 Mar 1972 — plausible, since their GB application was filed 6½ weeks later. Treat Brown as a motivating reference, not a bulletproof one.
• Not addressed here: the breadth of claim 1 relative to the three exemplified steroids raises a § 112(a) written description / enablement question (particularly under post-Ariad standards) and a possible "product-by-process" characterization of the claim-1 output (Abbott v. Sandoz). Those are § 112/§ 101 issues, outside the § 103 brief you asked for, but they are where I would look next.
• I did not re-verify the litigation/docket status of US 4,044,126 in this task; the prior section's finding of no 2026 CAFC activity and the 23 Aug 1994 expiry stand as given.