US 8026378

US patent 8026378, titled "Glyceryl ether compounds and their use," was filed on November 22, 2006, and issued on September 27, 2011. The inventor is Sergey Selifonov. The original assignee was Segetis Inc. Current assignees are listed as GF Biochemicals Ltd and Aromagen Corp, though the listed assignees may be inaccurate according to Google Patents.

The abstract describes the patent's subject matter: "Glyceryl ether compounds prepared by the reaction of glycerol and olefin epoxides are disclosed. The compounds are renewable biomass-based surfactants useful as detergents and emulsifiers in formulations for cleaning, laundry, personal care, cosmetics, and industrial uses."

Legal Status and CAFC Dockets:
As of April 26, 2026, the patent's legal status is "Expired - Fee Related," with an adjusted expiration date of May 25, 2028, according to the Google Patents entry. However, the legal events history indicates a "Lapse for failure to pay maintenance fees" on November 4, 2019, with the patent expiring due to nonpayment of maintenance fees under 37 CFR 1.362, effective September 27, 2019. This suggests the patent has already expired due to non-payment of fees, despite the listed adjusted expiration date. No cases explicitly mentioning US patent 8026378 were found in the publicly available CAFC scheduled dockets for May, June, or July 2026.

Plain-Language Overview of Independent Claims:

• Claim 1: This claim defines a specific chemical compound. The compound's structure features a central portion with a substituent (R6), which can be hydrogen or a linear or branched alkyl group with 1 to 10 carbon atoms. Attached to this central portion are two "V" groups. Each "V" group represents either a 2,3-dihydroxypropyloxy (glyceryl ether) structure or a protected version of it, specifically a 1,3-dioxolane or 1,3-dioxane ring with two alkyl groups (R4 and R5) attached, or a derivative with a hydroxyl group. Essentially, Claim 1 covers various glyceryl ether compounds, including both unprotected and protected forms.

• Claim 2: This claim describes a method for producing the compound specified in Claim 1. The method involves three main steps:

  • a) Providing either glycerol (an unprotected form) or a specific protected form of glycerol (a compound where R4 and R5 are independently chosen from hydrogen, linear/branched/cyclic alkyl, alkenyl, aryl, or arylalkyl groups).
  • b) Providing an epoxide-containing compound, which can be either an epoxidized triglyceride or an epoxidized unsaturated fatty acid ester. In the fatty acid ester, the fatty acid portion has 8 to 24 carbon atoms, and the alcohol portion is derived from a linear or branched monohydric alcohol with 1 to 12 carbon atoms.
  • c) Carrying out a chemical reaction between the compounds from step (a) and step (b) in the presence of an acid or base catalyst.

As of April 26, 2026, no litigation specifically involving US patent 8026378 was found through public search channels, including those typically indexing patent litigation such as Unified Patents, CAFC, and PACER.

While Unified Patents offers a portal for searching litigation cases, a direct search for US8026378 in public search results did not yield specific case entries from their database. Similarly, searches for "US8026378 litigation," "US8026378 lawsuit," "US8026378 CAFC litigation," and "US8026378 PACER litigation" did not return any records of lawsuits pertaining to this particular patent. The search results regarding PACER explain the general functionality of the PACER Case Locator as a national index for federal court cases, but do not provide specific litigation details for US8026378. Furthermore, the CAFC results discuss various appellate cases, none of which are related to patent US8026378.

Therefore, based on the available information, there is no known litigation involving US patent 8026378.

Proceedings overview

The USPTO ODP API returns no AIA trial proceedings for this patent as of the most recent ingest. Therefore, there is no PTAB activity on file for US patent 8026378.

Strategic summary

As there are no PTAB proceedings on file for US patent 8026378, all claims (Claims 1, 2, and 3) remain untested by AIA trial proceedings. This means there is no estoppel landscape established by PTAB decisions, and all prior-art grounds are theoretically still available for a potential petitioner. The absence of PTAB activity could indicate that the patent has not been extensively asserted, or that prior art challenges have not been deemed strong enough to warrant an AIA trial.

Recommended next steps

If you are a defendant facing assertion of US patent 8026378, the absence of PTAB activity means that you would be initiating the first AIA trial proceeding. This presents an opportunity to challenge the patent's validity without being constrained by previous PTAB decisions or estoppel. A thorough prior art search, building on the obviousness analysis provided, would be a critical first step to identify strong grounds for a petition for Inter Partes Review (IPR).

Inventors

The sole named inventor is Sergey Selifonov. At the time of filing, he was associated with Segetis Inc., the original assignee. No unusual patterns, such as the inventor departing the original assignee within 12 months of filing, were identified.

Original assignee

The original assignee on the issued patent is Segetis Inc.

• Product/Business: Segetis Inc. was involved in the development and commercialization of bio-based chemicals. Specifically, the patent describes glyceryl ether compounds as renewable biomass-based surfactants useful as detergents and emulsifiers in various formulations (cleaning, laundry, personal care, cosmetics, industrial uses).
• Current Status: Segetis Inc. was acquired by GFBIOCHEMICALS LIMITED, as evidenced by the assignment recorded on 2016-04-07.

Assignment timeline

• 2008-10-28 (executed) / recorded 2009-01-28 — Reel 022168/0071

  • Conveyance: ASSIGNMENT
  • Assignor: SELIFONOV, SERGEY
  • Assignee: AROMAGEN CORPORATION
  • Correspondent: Robert S. Haffner, Fish & Richardson P.C., 60 South Sixth Street, Suite 3200, Minneapolis, MN, 55402. This correspondent appears on multiple records in this chain.
  • Context: Inventor assigning rights to an initial corporate entity.

• 2008-10-28 (executed) / recorded 2009-01-28 — Reel 022168/0109

  • Conveyance: ASSIGNMENT
  • Assignor: AROMAGEN CORPORATION
  • Assignee: SEGETIS, INC.
  • Correspondent: Robert S. Haffner, Fish & Richardson P.C., 60 South Sixth Street, Suite 3200, Minneapolis, MN, 55402. This correspondent appears on multiple records in this chain.
  • Context: Transfer of rights from an initial corporate entity to the original operating assignee.

• 2016-02-05 (executed) / recorded 2016-04-07 — Reel 038373/0362

  • Conveyance: ASSIGNMENT
  • Assignor: SEGETIS, INC.
  • Assignee: GFBIOCHEMICALS LIMITED
  • Correspondent: Michael T. Hendershot, Dorsey & Whitney LLP, 50 South Sixth Street, Suite 1500, Minneapolis, MN, 55402.
  • Context: Acquisition of patent portfolio, indicating Segetis Inc. was acquired by GFBIOCHEMICALS LIMITED.

Timeline diagram

timeline
    title Ownership of US 8026378
    2006 : Patent filed by Segetis Inc
    2008 : Inventor to Aromagen Corp
         : Aromagen to Segetis Inc
    2011 : Patent issued
    2016 : Segetis to GF Biochemicals Ltd

NPE / troll-pattern signals

1. Shell-entity transfer — Unclear. While Aromagen Corporation acted as an intermediary, there is no definitive evidence that it was a shell entity for licensing-only purposes. The final assignee, GFBIOCHEMICALS LIMITED, is an operating company.
2. Known asserter in the chain — Not present. None of the assignees (Sergey Selifonov, Aromagen Corporation, Segetis Inc., GFBIOCHEMICALS LIMITED) are recognized as known patent asserters or NPEs.
3. Repeat correspondent across the chain — Present. Robert S. Haffner of Fish & Richardson P.C. appears as the correspondent for both the assignment from SELIFONOV, SERGEY to AROMAGEN CORPORATION (Reel 022168/0071) and from AROMAGEN CORPORATION to SEGETIS, INC. (Reel 022168/0109).
4. Cascading transfers — Present. Two consecutive assignments (Selifonov to Aromagen Corporation, then Aromagen Corporation to Segetis Inc.) were executed on the same date (2008-10-28) and recorded on the same date (2009-01-28), as shown in Reel 022168/0071 and Reel 022168/0109.
5. Pre-litigation transfer — Not present. No litigation involving this patent has been identified.
6. Bankruptcy fire-sale — Not present. There is no indication that any of the transfers were due to bankruptcy proceedings of the assignors.
7. Privateering — Not present. No evidence suggests a privateering arrangement. The current assignee is an operating company.
8. Defensive aggregator (anti-NPE) — Not present. The chain ends with GFBIOCHEMICALS LIMITED, an operating company, not a defensive aggregator.

Verdict

Insufficient data

Although there are signals of cascading transfers (Reel 022168/0071 and 022168/0109) and a repeat correspondent (Robert S. Haffner for both early transfers), these transactions appear to consolidate ownership from the inventor to the original operating company, Segetis Inc. The subsequent transfer to GFBIOCHEMICALS LIMITED (Reel 038373/0362) represents an acquisition by another operating company. There is no evidence of shell entities used for assertion, known NPEs in the chain, or any litigation, thus precluding a verdict of NPE assertion.

Verification: USPTO Assignment Center search for US8026378

To perform a thorough prior art analysis under 35 U.S.C. § 102, I will search the USPTO database for US patent 8026378 and then analyze the "Cited By" and "Citations" sections of the patent to identify relevant prior art references. I will confirm that each cited patent was published before the priority date of US8026378 (November 22, 2005) to be considered for a § 102 anticipation analysis.

Here's an analysis of the most relevant prior art for US patent 8026378, based on the patent's own citations:

1. US5442082A

• Full Citation: US5442082A, "Alkoxylated compounds produced from epoxidized carboxylic acid derivatives," issued August 15, 1995.
• Publication/Filing Date: Publication: 1995-08-15; Priority: 1990-01-26.
• Brief Description: This patent discloses alkoxylated compounds derived from epoxidized carboxylic acid derivatives, especially epoxidized fatty acid esters, by reaction with hydroxyl compounds in the presence of acid catalysts.
• Potential Anticipation (35 U.S.C. § 102):
  • Claim 1: This reference appears to anticipate Claim 1 by disclosing the broad class of compounds formed by reacting epoxidized fatty acid esters with hydroxyl compounds to create ether linkages. The specific "V" groups (2,3-dihydroxypropyloxy) and the R6 alkyl group, if not explicitly shown, would be routine variations within the scope of "hydroxyl compounds" and "alkoxylated compounds" when combined with glycerol.
  • Claim 2: This reference directly anticipates steps (b) and (c) of Claim 2 by teaching the use of epoxidized fatty acid esters as a starting material and effecting the reaction with a hydroxyl compound in the presence of an acid catalyst. If "glycerol" is considered a hydroxyl compound, then step (a) is also implicitly anticipated.

2. US20040077904A1

• Full Citation: US20040077904A1, "Production process for glycidyl ether adduct and catalyst used for the process," published April 22, 2004.
• Publication/Filing Date: Publication: 2004-04-22; Priority: 2002-08-29.
• Brief Description: This application describes a process for producing a glycidyl ether adduct by reacting a glycidyl ether with an alcohol (including polyvalent alcohols like glycerin) in the presence of an acid or base catalyst.
• Potential Anticipation (35 U.S.C. § 102):
  • Claim 2: This reference anticipates elements of Claim 2 by disclosing the reaction of an epoxide with glycerin (glycerol), which is a key component of step (a), and performing the reaction with an acid or base catalyst, as specified in step (c). While it specifically mentions glycidyl ethers, the principle of reacting epoxides with glycerol catalyzed by acid or base is directly applicable.

3. WO1992008685A1

• Full Citation: WO1992008685A1, "Amphiphilic non-ionic, glycerol-derived compounds, a method for preparing same, corresponding intermediate compounds and compositions containing said compounds," published May 29, 1992.
• Publication/Filing Date: Publication: 1992-05-29; Priority: 1990-11-14.
• Brief Description: This international publication discloses amphiphilic non-ionic compounds derived from glycerol, their preparation methods, and intermediate compounds. It focuses on glycerol derivatives used as surfactants.
• Potential Anticipation (35 U.S.C. § 102):
  • Claim 1: This reference broadly anticipates the concept of "glyceryl ether compounds" as "glycerol-derived compounds" used as "surfactants," particularly non-ionic ones. Depending on the specific structures disclosed, it could potentially anticipate the compounds of formula (8), (9a), or (9b) in whole or in part, especially concerning the glycerol-derived portion.
  • Claim 2: The "method for preparing same" in the description could anticipate aspects of Claim 2, particularly the reaction of glycerol with other compounds to form ether linkages, which is a common synthetic route for glycerol derivatives.

4. JPH04217972A

• Full Citation: JPH04217972A, "New carboxylic acid salt derivative and decomposable surfactant made thereof," published August 7, 1992.
• Publication/Filing Date: Publication: 1992-08-07; Priority: 1990-07-30.
• Brief Description: This Japanese patent describes new carboxylic acid salt derivatives and decomposable surfactants made from them.
• Potential Anticipation (35 U.S.C. § 102):
  • Claim 3: This reference appears to anticipate Claim 3, which focuses on converting the carboxyl ester group to a carboxylic salt. The existence of "carboxylic acid salt derivatives" as "surfactants" (as stated in JPH04217972A) demonstrates that this conversion for surfactant purposes was known prior to the priority date of US8026378.

5. EP0524548A1 / US5539001A (These appear to be related family members, so are discussed together for relevance)

• Full Citation: EP0524548A1, "Antimicrobial mixtures," published January 27, 1993; and US5539001A, "Antimicrobial mixtures," issued July 23, 1996.
• Publication/Filing Date: EP0524548A1 Publication: 1993-01-27; Priority: 1991-07-25. US5539001A Publication: 1996-07-23; Priority: 1991-07-25.
• Brief Description: These patents describe antimicrobial mixtures. While the primary focus is antimicrobial activity, the compositions may include glyceryl ether compounds as part of the mixture.
• Potential Anticipation (35 U.S.C. § 102):
  • Claim 1: If these references specifically disclose glyceryl ether compounds that fall within the structural limitations of Claim 1, they could anticipate it. Given the description of "glycerol-derived compounds" in related prior art, it's plausible that specific glyceryl ether structures might be present in these antimicrobial mixtures. Further detailed review of the specific compounds in these patents would be needed to confirm direct anticipation.

6. US4465866A

• Full Citation: US4465866A, "Preparation process of 2-hydroxy-3-alkoxypropylglyceryl ether," issued August 14, 1984.
• Publication/Filing Date: Publication: 1984-08-14; Priority: 1981-05-28.
• Brief Description: This patent details a process for preparing 2-hydroxy-3-alkoxypropylglyceryl ether.
• Potential Anticipation (35 U.S.C. § 102):
  • Claim 1: This reference directly describes a "glyceryl ether" compound. The specific structure 2-hydroxy-3-alkoxypropylglyceryl ether strongly overlaps with the general class of glyceryl ether compounds of Claim 1, particularly where the "V" group is a deprotected 2,3-dihydroxypropyloxy group. The "alkoxypropyl" portion can be analogous to the R6 alkyl and the fatty acid chain.
  • Claim 2: The "preparation process" described in this patent for a glyceryl ether compound would directly anticipate a method for preparing such compounds, including the fundamental steps of reacting an epoxide with glycerol or its derivatives.

7. JP2007016018A

• Full Citation: JP2007016018A, "Antibacterial agent," published January 25, 2007.
• Publication/Filing Date: Publication: 2007-01-25; Priority: 2005-06-08.
• Brief Description: This Japanese patent application describes an antibacterial agent.
• Potential Anticipation (35 U.S.C. § 102): While this patent is cited, its publication date (January 25, 2007) is after the priority date of US8026378 (November 22, 2005). Therefore, it cannot be considered direct anticipatory prior art under 35 U.S.C. § 102. However, its priority date (June 8, 2005) is before the priority date of US8026378, meaning the underlying invention could still be prior art, but the content of the later published document would need to be checked against an earlier corresponding document if one exists. For a 102 analysis, we strictly use the publication date of the document itself.

8. US6211329B1

• Full Citation: US6211329B1, "Process for preparation of a dendritic polyol," issued April 3, 2001.
• Publication/Filing Date: Publication: 2001-04-03; Priority: 1997-06-26.
• Brief Description: This patent describes a process for preparing a dendritic polyol. Dendritic polyols can have complex branched structures, potentially including numerous ether linkages and hydroxyl groups.
• Potential Anticipation (35 U.S.C. § 102):
  • Claim 2: This reference could anticipate general methods for forming polyether structures, which might overlap with the reaction steps in Claim 2, particularly if the dendritic polyols are formed through epoxide-alcohol reactions. The specific use of epoxidized triglycerides or fatty acid esters with glycerol, however, would need to be explicitly detailed in this patent to be a direct anticipation.

9. JPS54145224A

• Full Citation: JPS54145224A, "Cosmetic base," published November 13, 1979.
• Publication/Filing Date: Publication: 1979-11-13; Priority: 1978-05-02.
• Brief Description: This Japanese patent describes a cosmetic base. Cosmetic formulations often contain surfactants and emulsifiers, which could include glycerol derivatives.
• Potential Anticipation (35 U.S.C. § 102):
  • Claim 1: If this reference specifically discloses a glyceryl ether compound that meets the structural definition of Claim 1, it would be anticipatory. A more detailed review of the chemical components in the "cosmetic base" would be required to confirm this.

10. US5627144A

• Full Citation: US5627144A, "Composition for enhanced crude oil recovery operations containing hydrochloric acid or hydrofluoric acid, or mixtures thereof with ester quaternary ammonium compounds or/and alkyl quaternary ammonium compounds," issued May 6, 1997.
• Publication/Filing Date: Publication: 1997-05-06; Priority: 1992-09-11.
• Brief Description: This patent describes compositions for enhanced crude oil recovery. These compositions often utilize surfactants.
• Potential Anticipation (35 U.S.C. § 102):
  • Similar to JPS54145224A, this patent might contain disclosures of surfactant compounds that fall within Claim 1. However, without direct structural comparison, it's difficult to definitively state anticipation.

11. US20030167681A1

• Full Citation: US20030167681A1, "Procedure to obtain biodiesel fuel with improved properties at low temperature," published September 11, 2003.
• Publication/Filing Date: Publication: 2003-09-11; Priority: 2002-01-18.
• Brief Description: This application describes a procedure to obtain biodiesel fuel. The production of biodiesel often generates glycerol as a byproduct, and may involve fatty acid esters.
• Potential Anticipation (35 U.S.C. § 102): This reference is more relevant to the context and source materials (glycerol from biodiesel, fatty acid esters) rather than directly anticipating the specific glyceryl ether compounds or the detailed method of their formation. It highlights the availability of key starting materials.

12. JP4217972B2

• Full Citation: JP4217972B2, "Tubular element connection device," issued February 4, 2009.
• Publication/Filing Date: Publication: 2009-02-04; Priority: 2002-01-31.
• Brief Description: This patent describes a tubular element connection device.
• Potential Anticipation (35 U.S.C. § 102): This patent is unrelated to the chemical compounds or methods of US8026378. Its publication date (February 4, 2009) is also after the priority date of US8026378. It is highly unlikely to anticipate any claims.

Summary of Most Relevant Prior Art for Anticipation (35 U.S.C. § 102):

The most relevant prior art for direct anticipation under 35 U.S.C. § 102 appears to be:

• US5442082A: Directly addresses the formation of alkoxylated compounds from epoxidized fatty acid esters and hydroxyl compounds using acid catalysts, highly relevant to both the compounds (Claim 1) and the method (Claim 2).
• US20040077904A1: Specifically teaches the reaction of epoxides with glycerin (glycerol) in the presence of acid or base catalysts, which is a core part of the method in Claim 2.
• WO1992008685A1: Discloses amphiphilic non-ionic, glycerol-derived compounds and methods for their preparation, potentially anticipating the broad class of compounds in Claim 1 and aspects of the method in Claim 2.
• JPH04217972A: Anticipates Claim 3 by demonstrating prior knowledge of converting carboxyl esters to carboxylic acid salts for surfactant applications.
• US4465866A: Directly discloses a "2-hydroxy-3-alkoxypropylglyceryl ether" and its preparation, which strongly overlaps with the compounds and methods of US8026378.

These references individually provide strong indications of anticipation for various elements of the claims of US8026378, particularly for the general class of glyceryl ether surfactants and their synthesis from epoxides and glycerol or its derivatives, as well as the conversion of ester groups.

I'll ground a few facts about the prior-art references and the obviousness framework before building the § 103 analysis.

Strong grounding. Let me pull the exact claim-1 structure and the obviousness legal standard to tie the analysis together.

Obviousness Analysis — US 8,026,378 under 35 U.S.C. § 103

Builds on the "Prior art" section already generated. Where that section discussed single-reference § 102 anticipation, this section shifts to multi-reference § 103 combinations. One substantive correction to the earlier section is flagged in Part J.

A. Legal framework and critical date

• Critical date: November 22, 2005 (priority). Every reference relied on below published before that date. I confirm the one date-sensitive item — JP2007016018A — cannot be used, because the earlier section correctly noted its publication (2007‑01‑25) post-dates the priority date. It drops out of the § 103 analysis entirely.
• Standard: Graham v. John Deere, 383 U.S. 1 (1966) (scope/content; differences; PHOSITA level; secondary considerations), applied through KSR Int'l v. Teleflex, 550 U.S. 398 (2007). Under KSR, a combination is obvious where the elements were known, the references are from the same field or analogous fields, and there was a finite, predictable set of solutions with a reasonable expectation of success. A motivation may be explicit, implicit in the problem, or supplied by "common sense." MPEP §§ 2141–2144.
• PHOSITA: a synthetic organic/surfactant chemist with a B.S./M.S. plus several years in oleochemicals, familiar with epoxide ring-opening, ketal/acetal protection of glycerol (solketal chemistry), and fatty acid/triglyceride epoxidation.

B. Claim scope (recap, then differences)

• Claim 1 — compound with an ester fragment R6 (H or C1–C10 alkyl) and two glyceryl-ether "V" moieties (di-protected and/or de-protected 2,3-dihydroxypropyloxy forms). Structurally this corresponds to the oxygenated fatty-acid-ester derivatives bearing two pendant glyceryl-ether groups that the specification itself describes as "di(glyceryl)ether adducts … comprising two hydroxyl groups and two pendant glyceryl ether groups" (spec., compounds (16a)/(17a)–(17d) family).
• Claim 2 — method: (a) glycerol or protected glycerol (R4/R5 ketal/acetal, i.e. solketal-type); (b) an epoxidized triglyceride or epoxidized unsaturated fatty acid ester (C8–C24 acid, C1–C12 monohydric-alcohol fragment); (c) reaction in the presence of an acid or base catalyst.
• Claim 3 — the method of claim 2 plus converting the carboxyl-ester group to free acid, salt, or amide.

The differences over the art are therefore narrow: an ester-bearing fatty chain, two glyceryl-ether pendants, and the choice of acid-or-base catalysis on a protected glycerol.

C. Claim 1 (compound) — combinations rendering it obvious

Combination 1‑1 (primary): WO1992008685A1 (L'Oréal) + US4465866A (Kao Soap)

• WO1992008685A1 claims and discloses nonionic amphiphilic, glycerol-derived compounds of formula (I) — glycerol derivatives bearing lipophilic chains and glyceryl-ether hydrophilic heads — and expressly identifies the compound class as surface-active agents. Its worked chemistry (below, Part D) produces exactly this genus. (Google Patents WO1992008685A1)
• US4465866A discloses 2-hydroxy-3-alkoxypropylglyceryl ether and its synthetic intermediate 4-(2′-hydroxy-3′-alkoxy)propoxymethyl-1,3-dioxolane, where R is C8–C24 aliphatic and the dioxolane carries R1/R2 = H, lower alkyl, aryl or aralkyl. (Google Patents US4465866A)
• Why the combination meets claim 1: the de-protected "V" (2,3-dihydroxypropyloxy) reads directly on US4465866's glyceryl ether; the protected "V" (1,3-dioxolane with two R groups) reads directly on US4465866's intermediate. WO1992008685 supplies the amphiphilic/surfactant genus and the multiple-chain (i.e., di-substituted) variants. The only element not literally shown is the ester R6; that is supplied by Combination 1‑2.

Combination 1‑2: Combination 1‑1 + US5442082A (Henkel) + Wedmid NPL

• US5442082A is directed to compounds made from epoxidized C10–C22 carboxylic acid derivatives — i.e., fatty-acid esters/triglycerides — thereby supplying the ester functionality (R6) and confirming that these substrates are legitimate, known feedstocks for polyol adducts.
• Wedmid et al., J. Org. Chem. 42(22), 3624–3626 (1977) — "Long-chain stereomeric 2-alkyl-4-methoxycarbonyl-1,3-dioxolanes in glycerol acetal synthesis" — discloses a protected glycerol ring bearing an ester (methoxycarbonyl) group in the 4-position. That is structurally an R6-ester on a ketal-protected glycerol — precisely the R6/V motif claimed.
• Motivation / predictability: all three disclosures are in glycerol-derived ether/ester chemistry; a PHOSITA seeking an ester-bearing glyceryl-ether surfactant would routinely (i) keep the ester of the fatty-acid feedstock, (ii) install the glyceryl-ether head via epoxide opening, and (iii) optionally ketal-protect — all finite, predictable choices. This is the KSR "predictable variation" scenario.

Combination 1‑3 (corroborating): Karabina & Borredon (NPL) + Muramatsu & Schmid (NPL) + Baskaran (NPL)

• Karabina & Borredon, Synthetic Communications 24(21), 3009–3019 (1994) explicitly reports "hydroxyethers (monomers and dimers) from glycerol and several fatty chains 1,2-epoxyalkanes" — i.e., the very glyceryl-ether compounds, including the dimeric (two-chain) species that map onto claim 1's "two V" compounds. Abstract
• Muramatsu & Schmid, Chem. Phys. Lipids 9(1), 123–132 (1972) discloses 1-O-(2′-hydroxyalkyl)glycerols (the de-protected compound); Baskaran et al., Tetrahedron 52(18), 6437–6452 (1996) discloses 1-O-(2′-hydroxy-hexadecyl)glycerol. Both are species-level disclosures of the de-protected claim-1 genus.
• These NPL references are cited on the face of the patent itself, so the applicant cannot dispute they are analogous art.

D. Claim 2 (method) — combinations rendering it obvious

Combination 2‑1 (strongest): WO1992008685A1 + US5442082A

This is the cleanest § 103 case against claim 2 because WO1992008685 maps onto step (a) protected glycerol, step (b) epoxide, and step (c) base catalyst almost element-for-element:

WO1992008685 also expressly performs the two-stage protect → react → hydrolyze sequence (base-catalyzed opening of the epoxide by isopropylidene glycerol, then acid-catalyzed hydrolysis to the free glyceryl ether) — which is the exact architecture the patent's claim 2 and Examples 1–6 use. US5442082 supplies the fatty-acid-ester/triglyceride identity for step (b) that WO1992008685 states generically.

Motivation (explicit + implicit): both references are directed to the same problem — converting renewable glycerol and epoxidized oleochemicals into non-ionic surfactants/emulsifiers. US5442082's own background states the aim of finding a "substitute for alkoxylated castor oils" from a "broader and less crisis-prone raw material base … ecologically and toxicologically safe" (US5442082A). A PHOSITA facing the patent's stated objective (surfactants from glycerol + olefin epoxides) would look to exactly these two references and combine them with a reasonable expectation of success, because each half of the reaction was already demonstrated to work.

Combination 2‑2: US4465866A + US5442082A + US20040077904A1

• US4465866A actually performs the claimed strategy: reacting an alkyl glycidyl ether with an acetal or ketal of glycerol in the presence of an acidic or basic catalyst to give a 1,3-dioxolane, followed by hydrolysis to the glyceryl ether. It even recites R = C8–C24 and discusses the by-product problem that motivates using protected glycerol — the same rationale the patent gives.
• US5442082A swaps in the epoxidized fatty-acid ester/triglyceride as the epoxide.
• US20040077904A1 (Kao) teaches a glycidyl-ether-adduct process using glycerin (glycerol) with an acid or base catalyst. (Google Patents US20040077904A1)
• Motivation: three references, same reaction class (epoxide + polyol → ether adduct), same catalyst families, same product purpose. The combination is the KSR-favored "simple substitution" of one known epoxide for another known epoxide in a known reaction.

Combination 2‑3: Karabina & Borredon + US20040077904A1 (+ US5442082A)

Karabina discloses glycerol + fatty-chain C8–C16 1,2-epoxyalkanes, using two acid catalysts (Dowex M31 resin, activated earth) and two base catalysts (CH₃ONa, CH₃COONa) — a literal reading of "acid or base catalyst" on a C8–C16 fatty epoxide. US2004/0077904 and US5442082 extend this from the NAO epoxide to the epoxidized fatty-acid ester/triglyceride epoxide. The overlap with claim 2 step (b)'s carbon-number ranges (C8–C24, C1–C12) is routine optimization.

E. Claim 3 (ester → acid / salt / amide) — obvious

Claim 3 adds only routine carboxyl derivatization:

• JPH04217972A discloses carboxylic-acid salt derivatives as decomposable surfactants — establishing that saponification of an ester to a surfactant salt was known.
• US5442082A and the patent's own cited art establish that these adducts are surfactant esters, and fatty-ester saponification/transesterification is the single most routine operation in oleochemistry (also evidenced by the patent's own cited biodiesel literature, e.g. the Ma Bioresource Technology and Suppes JAOCS reviews, and Ono et al., JAOCS 70(1) (1993), "a New 'Soap' Bearing a 1,3-Dioxolane Ring").
• Motivation: converting a fatty ester to its salt is the standard route to an anionic surfactant and to hard-water-compatible carboxylates; a PHOSITA would do this with a reasonable expectation of success. Claim 3 is essentially a non-inventive "and then saponify" step.

F. Cross-cutting motivation and reasonable expectation of success

1. Same field / same problem. Every reference is glycerol-derived ether/ester surfactant chemistry aimed at hard-water-compatible, renewable non-ionics. MPEP § 2141.01(a) analogous-art test is easily met.
2. Explicit motivations in the references themselves. US5442082's stated goal (castor-oil substitute from a "less crisis-prone" raw-material base) and WO1992008685's stated utility ("surface-active agents," vesicle-formers for cosmetics) point directly at the patent's objective. The 2004–2005 biodiesel literature cited on the patent's face (glycerol as a cheap by-product) supplies the economic motivation to use glycerol.
3. Finite, predictable solutions (KSR). The claimed variables are the classic optimization knobs: ester vs. free acid (R6 = H vs. alkyl); C8–C24 fatty chain; C1–C12 alcohol; ketal vs. acetal protection; acid vs. base catalysis; protected vs. unprotected glycerol. Each option is a small, enumerated set with predictable effect — the KSR "predictable variations of known elements" scenario.
4. Reasonable expectation of success. The reaction itself was already performed in the art: WO1992008685 runs isopropylidene glycerol + epoxide/base → hydrolyze; US4465866 runs glycidyl ether + glycerol ketal → hydrolyze; Karabina runs glycerol + fatty epoxyalkane with both acid and base catalysts. There is no teaching that any claimed combination would fail. The patent's own examples (solketal or menthone/camphor ketals at 25–60 °C with BF₃·OEt₂, then deprotection) are routine optimizations of these known reactions.

G. Anticipated rebuttals / secondary considerations

• "Hard-water tolerance is unexpected." Not persuasive. The patent itself concedes the compounds "are non-ionic surfactants, and their surfactant and emulsifying … properties are not substantially affected by the presence of alkali-earth metal ions." Insensitivity to Ca²⁺/Mg²⁺ is a known, inherent property of non-ionic surfactants, as taught by the Non-Patent Citation Salager, Surfactants Types and Uses, FIRP Booklet #E300‑A (2002) (cited on the patent's face) and by WO1992008685's non-ionic amphiphiles. No unexpected result.
• "Preference for 1,2-ketals / avoidance of acetals." The specification's preference for 1,2-ketals over acetals (peroxide/odor concerns) is a preference, not a teaching away: claim 1/claim 2 expressly embrace acetals (R4 or R5 = H) and both 1,2- and 1,3-dioxolane/dioxane forms. A preference among disclosed alternatives does not defeat obviousness.
• "Commercial success / long-felt need." No evidence of record in this analysis (no litigation, no PTAB, no sales/nexus data). Even if the current assignee (GF Biochemicals) later adduces commercial success, it must show the success is coextensive with the claimed invention and not attributable to the already-known reaction chemistry or to the biodiesel-driven glycerol cost collapse.

H. Strength assessment, claim by claim

Overall: the patent sits in a crowded, well-developed space. Each independent claim is a narrow increment over known glycerol-epoxide adduct chemistry, and claim 2 — the commercial core — is the most exposed because WO1992008685A1 and US4465866A effectively practiced the claimed protect/react/deprotect sequence years earlier, merely with a slightly different epoxide that two other references supply.

I. Caveats / where I have lower confidence

1. The "V" Markush structures are images and did not render in the retrieved text. My claim-1 mapping is inferred from the specification's own product formulae ((16a),(16b),(17a)–(17d)) and the "di(glyceryl)ether adducts … two pendant glyceryl ether groups" passage. A precise element-by-element chart should be built from the granted-claim drawings.
2. WO1992008685's epoxide scope. I rely on the retrieved formula (III) R = C4–C28 alkyl/alkenyl or –CH₂A (A = –OR′, –SR′, or –O–C(=O)R′). Whether the ester variant (A = –O–C(=O)R′) is actually exemplified — versus merely within the generic formula — should be verified against the WO publication before relying on it alone for step (b). If it is only generic, the combination leans more heavily on US5442082 for the fatty-ester epoxide.
3. The patent's NAO-epoxide embodiments (claims directed at "one of R1/R2 = C6–C30 alkyl") are supported by Karabina/Baskaran but are not the subject of the three granted claims analyzed here.
4. Post-2019 status — the patent lapsed for non-payment of maintenance fees (effective 2019‑09‑27, per the Legal Events), so a § 103 analysis is presently of historical/validity-challenge value rather than of live-infringement value.

J. Explicit contradiction flag (per instructions)

The earlier "Prior art" section characterized US5442082A as disclosing "alkoxylated compounds … by reaction with hydroxyl compounds in the presence of acid catalysts," implying a direct glycerol-opening of the epoxide. The actual reference (per the retrieved abstract and specification) teaches reaction of epoxidized C10–C22 carboxylic acid derivatives with C2–C4 alkylene oxides in the presence of alkoxylation catalysts (sodium methylate / KOH) and mono-/polyhydric alcohols, at 110–220 °C. That is a distinct mechanism (alkoxylation, not direct polyol ring-opening) and a distinct catalyst class from the patent's acid/base ring-opening.

Consequence for this § 103 analysis: US5442082A is best used as evidence that (i) epoxidized fatty-acid esters/triglycerides are known adduct-forming feedstocks, and (ii) glycerol/polyglycerol are among the taught polyol co-reactants — but not as a standalone teaching of the claimed acid/base-catalyzed opening. The direct-opening teaching comes from WO1992008685A1, US4465866A, Karibana & Borredon, and US2004/0077904A1. This refinement strengthens the reliance on WO1992008685A1 as the primary claim‑2 reference and demotes US5442082A to a supporting role — a correction to the earlier section's suggestion that US5442082A alone "directly anticipates" claim 2.